Australian Welding June 2017

AUSTRALIAN 1

WELDING Q2 | JUNE 2017 www.wtia.com.au

LASER CLADDING

FOR RAILWAY REPAIR PAGE 32 2017 NATIONAL

MANUFACTURING WEEK (NMW) PAGE 10 CALLIDUS WELDING:

ENGINEERING EROSION & CORROSION SOLUTIONS PAGE 28

JOURNAL OF THE WELDING TECHNOLOGY INSTITUTE OF AUSTRALIA Welding Technology Institute of Australia

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AUSTRALIAN WELDING | JUNE 2017

Laser Cladding for Railway Repair

P32

Tips for Welding Titanium

P22

Welding Safety Hazards

P18 WTIA National Office

Chief Technology Officer

Membership Manager

Building 3, Level 3, Suite 5 20 Bridge Street Pymble, NSW 2073 (PO Box 197 Macquarie Park BC, NSW 1670) T: +61 (0)2 8748 0100 E: info@wtia.com.au

Bruce Ham T: +61 (0)418 391 534 E: b.ham@wtia.com.au

Donna South T: +61 (0)2 8748 0130 E: d.south@wtia.com.au

Qualification & Certification Manager

Advertising

Chief Executive Officer Geoff Crittenden T: +61 (0)2 8748 0100 E: g.crittenden@wtia.com.au

Annette Dickerson T: +61 (0)2 8748 0170 E: a.dickerson@wtia.com.au Training Manager Paul James T: +61 (0)2 8748 0150 E: p.james@wtia.com.au

Donna South T: +61 (0)2 8748 0130 E: d.south@wtia.com.au Editorial Submissions Sally Wood T: +61 (0)434 442 687 E: sally@wordly.com.au

CONTENTS Q2 2017

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Australia’s Advanced Manufacturing Council

P24 NMW 2017

P10 CONTENTS

Q2 2017 From the WTIA CEO

Callidus: Engineering Solutions to Erosion and Corrosion

P28 About the WTIA A membership-based organisation, the Welding Technology Institute of Australia (WTIA) represents Australia’s welding profession. Our primary goal is to ensure that the Australian welding industry remains locally and globally competitive, now and into the future. WTIA is the Australian representative of the International Institute of Welding (IIW).

Subscription to the Australian Welding Journal is a WTIA member benefit included in annual membership fees. All rights reserved. No part of this publication may be reproduced or copied in any form without the written permission of the WTIA. The WTIA and its agents are not responsible for statements or opinions expressed by contributors in this publication, which are not necessarily those of the WTIA. Publication of any advertisement does not constitute endorsement by the WTIA of any product, nor warrant its suitability.

Inside the Industry Breaking News National Manufacturing Week Australian Standards Business Essentials

Health & Safety Shipbuilding Accuracy Control Tips for Welding Titanium Manufacturing Council Callidus Welding Solutions State Focus: South Australia Laser Cladding for Railways

Inside the WTIA Q&A With A WTIA Member Hotline Report SMART Industry Groups Member Directory Upcoming Events

4 6 10 14 16 18 20 22 24 28 30 32 42 44 46 48 51

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AUSTRALIAN WELDING | JUNE 2017

From the

WTIA CEO Many companies have achieved certification to ISO 9001 for their quality management systems. But where a special process like welding is used, this certification simply cannot demonstrate the capability of a company to manufacture products of the required quality. ISO 3834 certification (published in Australia as AS/NZS ISO 3834) overcomes this shortfall, boosting a company’s ability to sell its products in domestic and overseas markets. And yet, Australian welding companies have been reluctant to adopt ISO 3834 certification.

As an International Institute of Welding (IIW) Authorised National Body (ANB), the WTIA has struggled to gain traction for many years in persuading corporate members to become certified to ISO 3834 Quality requirements for welding.

The principle reason we’ve had so much difficulty engendering enthusiasm from our members for ISO 3834 is that there is a false impression that the Standard is a quality management system.

Therefore, many members believe that if their company already holds certification to ISO 9001 Quality management, another quality certification is unnecessary.

However, in reality, ISO 3834 is a factory production control (FPC) system, drafted to compliment quality management systems including ISO 9001. ISO 3834 identifies the essential elements associated with welding and related processes that, when appropriately managed, ensure internationally recognised quality requirements for the welding of metallic materials by fabricators, manufacturers, constructors and maintainers.

Regrettably, as a result of these widespread misconceptions, Australian industry lags a long way behind other developed nations.

This became apparent to me during a recent SMART Defence Industry Group meeting.

During the SMART Group meeting, the supply chain manager for Rhienmetall (who are currently shortlisted for the LAND 400 project) explained that, in Germany, he would be lucky to find five companies that were not certified to ISO 3834. Yet, in Australia, he has been lucky to find five companies that are certified.

ISO 3834 is the minimum benchmark for welding quality globally. As more companies become certified to the Standard, those companies without certification will find it harder to win work from local and international suppliers alike, particularly international Defence prime contractors (like Rhienmetall), who simply expect this certification as standard.

However, I’m pleased to report that there is increasing acceptance of ISO 3834 by Australian industry, driven by the substantial number of Defence industry projects that are entering the planning phase.

In addition, the 2017 revision of the Australian bridge design code AS/NZS 5100.6 makes normative references to AS/NZS ISO 3834.2 and 3. This is the first Australian standard that makes non-optional normative references to these two parts of the standard.

This growing acceptance is extremely encouraging. The WTIA wants to see every Australian company involved in welding

Geoff Crittenden, WTIA CEO.

certified to ISO 3834, particularly as the benefits of certification are so wide-ranging.

Certification to ISO 3834 improves client satisfaction, and increases the likelihood of business opportunities, repeat business and growth in profitability. It helps Australian businesses demonstrate their ability to deliver a compliant welded product on time and to budget.

Certification to the standard fosters credibility and international recognition, clarity on technical requirements through a formal review process, and it promotes and increases the technical knowledge of all levels of personnel involved in the welding process (from trades and inspectors, through to supervisors and management).

To ensure the proper quality of welded products and to optimise manufacturing costs, the entire welding process must be controlled from design, right through to completion. All aspects that could affect welding quality must be taken into account. The best way to do this is to implement a quality assurance system certified to ISO 3834.

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AUSTRALIAN WELDING | JUNE 2017

Inside the Industry:

Breaking News UGL Awarded $117 million in Solar Projects UGL has been awarded engineering, procurement and construction (EPC) contracts to design and build two new solar farms. The two EPC contracts – for the Collinsville Solar Farm in Queensland and the White Rock Solar Farm in New South Wales – will generate combined revenue for UGL of $117 million. In addition, UGL will provide operation and maintenance (O&M) services at both solar farms.

UGL Managing Director Juan Santamaria said: “UGL’s early involvement with our customers, true end-toend capabilities, and technical expertise are strong market differentiators. We have a proven track record in the design and delivery of solar farms, and this has been instrumental in securing these opportunities. We have established a national operational control and monitoring centre to support the company’s increasing portfolio of utility scale solar farm O&M contracts.”

The existing ANZAC Class Frigates. Image courtesy of the Commonwealth of Australia, Department of Defence.

Government Releases Naval Shipbuilding Plan The Turnbull Government released Australia’s first Naval Shipbuilding Plan in May, outlining the nation’s largest ever program of naval shipbuilding and sustainment.

The plan includes a commitment of $1.3 billion to develop vital infrastructure in Australia’s shipyards so that the Navy’s next generation of naval vessels can be built in Australia.

According to the Government, the Naval Shipbuilding Plan will end the boom-bust cycle that has afflicted the industry for many years, providing certainty for local businesses and shipbuilding workers.

The Plan will ensure delivery of these modern defence capabilities set out in the 2016 Defence White Paper, creating thousands of jobs and securing the naval shipbuilding and sustainment industry for future generations of Australians.

Furphy stainless steel tanks.

Furphy Engineering Upgrades Plant Furphy Engineering has recently expanded and upgraded the facilities at their Shepparton Plant in Victoria in a bid to ensure they continue delivering the highest quality stainless steel tanks. These upgrades include a new Undercover Inspection Zone, where every tank undergoes rigorous Q&A prior to delivery. Furphy has also installed a Vertical Seam Planishing Machine to complement their automated strake fabrication process. These machines are fully automated, ensuring a consistent polished finish with even stress relief on all welded seams. A new strake transfer rail has been installed, which will efficiently move strakes throughout their production process, improving production efficiencies.

Work will commence this year on the development of infrastructure at the Osborne Naval Shipyard in South Australia. The Henderson Maritime Precinct in Western Australia will also be upgraded.

The upgrades will include construction of new cranes and heavy lift transportation capability, welding stations and upgrades to workshops and storage facilities including new steel framed sheds.

The naval shipbuilding workforce is expected to grow to around 5,200 workers by the mid to late 2020s, with more than double this number of workers in sustainment activities and throughout supply chains across Australia.

The Naval Shipbuilding Plan can be downloaded from the Department of Defence website: www.defence.gov.au

INSIDE THE INDUSTRY: BREAKING NEWS

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Snowy Hydro Expanding Pumped Hydro Storage

BAE Renews Global Supply Chain Agreement

The iconic Snowy Scheme’s role as the battery of the National Electricity Market (NEM) could be supercharged as part of plans to expand the pumped hydro storage capability within the Scheme. Snowy Hydro, working with the Australian Renewable Energy Agency (ARENA), will shortly commence a feasibility study into several sites across the Scheme which could support new large-scale, pumped hydro-electric energy storage. The proposal could add up to 2000MW of new renewable energy to the NEM and act as rapid response back-up to fill the gaps in energy supply caused by intermittent renewables and generator outages.

BAE Systems Australia recently announced the renewal of their Global Supply Chain Agreement, confirmed

by Minister for Defence Industry, Senator the Hon. Christopher Pyne.

The agreement allows BAE to continue to provide Australian companies with access to commercial and defence opportunities within BAE Systems international business. In 2016, they had contracts with over 24,000 suppliers and a global spend of almost $15 billion. In Australia BAE’s supply chain consists of over 1,600 companies purchasing goods worth $360 million, generating a GDP contribution of $210 million.

BAE Systems Australia has one of the nation’s largest defence supply chains and a long and successful history of working closely with Australian suppliers, to open up both local and international opportunities.

Since its inception in 2012, BAE’s Global Access Program has recorded a number of export successes for Australian businesses including military vehicle restraint systems, ship evacuation equipment, precision components for the aerospace sector, armored steel and various software analysis tools.

L to R: 100th Designer Abby Krause (Design Draftperson), Minister Cash and David Singleton (Austal CEO).

Austal Opens Shipbuilding Office in Adelaide Austal has announced the establishment of a new design and project management office in Adelaide, South Australia, to support the company’s expansion into one of Australia’s two major shipbuilding hubs.

Fifteen Australian businesses have directly benefitted from the Global Access Program by securing export contracts and over 100 companies have taken advantage of various training programs, overseas trade missions, and international networking events facilitated by the program.

The new office will initially support preparations for the Australian Government’s $3 billion Offshore Patrol Vessel (OPV) project, which will see 12 vessels constructed for the Royal Australian Navy from 2018. It will also enable Austal to prepare for the Government’s Future Frigate project, comprising nine vessels to be constructed in Adelaide from 2020.

Glynn Phillips, BAE Systems Australia Chief Executive said, “The diversity of our Australian business across air, land and sea means we are well placed to identify opportunities in the global business and match those with competitive local companies. Opening the door to international opportunities supports the growth of and helps to sustain Australia’s defence industry. Success for Australia’s industry works to promote innovation, improve our ability as a nation to compete globally and generate exports and jobs,” said Phillips.

Austal recently welcomed Minister for Employment, Senator the Hon. Michaelia Cash, to a ceremony recognising the company’s milestone of employing over 100 people in its world-renowned naval design team.

Minister Cash toured Austal’s Henderson facilities to see firsthand how Austal is contributing to Australian capability in the shipbuilding industry, especially with respect to exports.

BAE Systems is supporting Australian businesses to qualify for and pursue export opportunities in the United States, the United Kingdom, Turkey, Sweden, Finland, Germany and Japan, across land, air, sea and electronic systems domains. As well as identifying opportunities and providing introductions, BAE Systems Australia also support companies with mentoring, assistance with qualification, and proposal writing.

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Inside the Industry:

Breaking News APA Group Invests in Darling Downs Solar Farm APA Group recently announced that it will purchase the Darling Downs Solar Farm, with an option to acquire the nearby Beelbee Solar Farm Development site, which has the potential for an additional 150MW of solar energy generation.

A $20 million grant from the Australian Renewable Energy Agency (ARENA) Advancing Renewables Programme will help APA fund the $200 million acquisition and development of the 110MW Darling Downs Solar Farm. Construction is expected to be completed by late in 2018.

The Darling Downs Solar Farm site is located 45km west of the town of Dalby in south-western Queensland and will utilise the existing Darling Downs Braemar substation, which connects into the National Electricity Grid. The Darling Downs Solar Farm is expected to generate enough electricity to power 32,000 homes.

L to R: Ian Irving (Chief Executive of Northrop Grumman Australia), Prime Minister Malcolm Turnbull, and Dave Perry (President, Northrop Grumman International).

Northrop Grumman Expands Australian Operation Northrop Grumman has opened a new repair facility at the Royal Australian Air Force (RAAF) Edinburgh base in South Australia to provide more efficient in-country support services for the repair and maintenance of laserbased Large Aircraft Infrared Countermeasures (LAIRCM) systems. LAIRCM systems are currently installed on six RAAF aircraft types, 57 aircraft in total, with plans to add three additional platforms in the next five years.

Northrop Grumman’s LAIRCM system automatically detects a missile launched at an aircraft, determining if it is a threat and activating a high-intensity laser-based countermeasure system to track and defeat the missile. LAIRCM systems are either installed or scheduled for installation on more than 1,500 military aircraft worldwide to protect more than 75 different large fixed-wing transports and small rotary-wing platforms from infrared missile attacks.

Northrop Grumman also announced that it will invest $50 million in the development of an advanced defence electronics maintenance and sustainment centre in Western Sydney. The centre will be located in the Badgerys Creek precinct, where Northrop Grumman will be the anchor tenant for an advanced aerospace and defence industries precinct.

APA Group Managing Director, Mick McCormack said, “I am always pleased to announce new growth projects.

APA continues to grow its capabilities in owning and operating significant energy infrastructure as part of its growth strategy. This renewables project sits well with APA’s successful and sustainable investment criteria.”

Longford Gas Conditioning Plant Complete Esso Australia recently announced the completion of its Longford Gas Conditioning Plant, which processes gas from the Kipper Tuna Turrum development. Production from the gas conditioning plant marks the completion of the $5.5 billion Kipper Tuna Turrum development – the largest domestic gas project on Australia’s eastern seaboard. The development will supply 1.6 trillion cubic feet of gas to eastern Australia – enough to power a city of one million people for 35 years.

A Kipper subsea cooler is installed.

INSIDE THE INDUSTRY: BREAKING NEWS

Starfish Hill Wind Farm in Cape Jervis, South Australia.

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Dylan Bolch: Welding His Way to a Secure Future Twenty-two year old welder Dylan Bolch has big dreams and a firm plan as to how he is going to achieve them with step one being named as a member of the WorldSkills Australia Skillaroos team going to Abu Dhabi.

With this goal firmly in mind, four days a week after working with Macquarie Manufacturing, Dylan goes to TAFE NSW Newcastle to train for a further four hours in the evening. Not content with this, he trains a further two to three hours on a Friday night at work.

Government to Improve South Australia’s Power The State Government of South Australia has unveiled a comprehensive plan to take charge of the State’s energy future and deliver reliable, affordable and clean power for South Australians. South Australian Power for South Australians will ensure more of the State’s power is sourced, generated and controlled in South Australia.

The $550 million plan will increase security, boost competition and put downward pressure on prices.

As part of the plan, the South Australian Government will build Australia’s largest battery to store energy from the wind and sun, part of a new Renewable Technology Fund that supports clean, dispatchable and affordable power. A government-owned 250MW gas-fired power plant will also be constructed to provide emergency back-up power in times of peak demand to prevent future blackouts. The new fast-start aeroderivative plant is expected to cost $360 million. The South Australian Government is assessing potential sites for the plant, with the procurement process expected to begin as soon as possible.

Rheinmetall to Partner with Supashock Rheinmetall MAN Military Vehicles GmbH (RMMV) announced a partnership with Adelaide based suspension and technology company Supashock for the development and manufacture of a revolutionary military suspension and integrated intelligent load handling system for its range of military trucks. RMMV has funded Supashock to develop the system for the Australian and global markets. The system integrates Supashock’s novel active suspension technology with an intelligent load handling system and will substantially increase the capability and safety of RMMV’s military trucks in demanding on and off-road environments.

“Sometimes it’s tough juggling everything, but I don’t mind making these sacrifices in time as I know I am fully committed to being the best welder I can be. The best thing is I see my skill level increasing each day. At work, we sometimes get jobs just because of my skills and what I can do which I really enjoy,” said Dylan.

Dylan is being supported on his journey to hopefully being picked to go to Abu Dhabi by the Welding Technology Institute of Australia (WTIA). “It’s great to be supported by the industry as I reach for my goals.”

He is also benefitting from extra training by 2013 Bronze Medallist Lachlan Mayled. “I spent a couple of weeks with Lachlan and he ‘smashed me’ every day. We really worked hard, plus he was also able to give me pointers about competing at an international level as he has been there himself.”

Dylan was to have travelled to China this month for training, but this has been postponed; “so I’m hoping to be able to spend some more time with Lachlan instead.”

Dylan’s final hurdle before he knows if he will become a Skillaroo is the Global Skills Challenge. To be held in Newcastle, this is a four-day competition that will pit young people from 15 nations against each other. In welding, there will be eight nations with Dylan up against competitors from Canada, China, Japan, New Zealand, Russia and the USA. So what about the rest of Dylan’s plan? “After I make the team I want to win a medal. Then one day I’d like to open my own welding business. I’d also like to start a program to help juveniles get into trades.”

If Dylan’s dedication to making the Skillaroos team is anything to go by, his future looks very bright.

Source: www.worldskills.org.au

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AUSTRALIAN WELDING | JUNE 2017

2017 National

Manufacturing Week National Manufacturing Week (NMW) returned to Melbourne from May 9 to 12, cementing its reputation as Australia’s largest gathering of manufacturing industry decision-makers. This year’s conference was one of the largest to date, with early reports indicating that more than 10,000 people attended the four day event. Held at the Melbourne Convention and Exhibition Centre, NMW featured more than 50 speakers and various networking opportunities for those working within the manufacturing value chain.

More than 230 exhibiting companies showcased the latest manufacturing technologies, developments and programs. Supported by the Welding Technology Institute of Australia (WTIA), NMW’s Welding Technology Product Zone provided a dynamic environment of live demonstrations featuring welding, heat-treating, joining and associated products and technologies.

Some of the welding industry’s

leading companies exhibited, including BOC, Supagas, Lincoln Electric, Metal Science Technologies, Robot TechnologiesSystems Australia and Ensitech.

Live demonstrations ran over the four days, including a session by Peter Kuebler (Technical Manager Specialised Manufacturing of BOC), on the effects that shielding gases have on welding arcs through the Kawasaki welding robot.

NMW 2017 focused on innovations in the manufacturing industry.

With the world in the midst of a fourth industrial revolution, local manufacturers must adapt to the rapid pace of technological change, an increasingly international global value chain, and the changing nature of manufactured product and service opportunities.

The keynote presentation by John Pollaers (Chairman of the Australian Advanced Manufacturing Council) was a highlight of the conference. Speaking on the topic of ‘Scaling Up Australian Manufacturing’, Pollaers explored the key characteristics of successful prime and SME manufacturers, emerging market opportunities, workforce development needs and recommended government actions to grow the scale of Australian manufacturing.

According to Pollaers, “The past two to four years have seen important changes not only in the way Australians think about manufacturing but in the way we see the world. There is a major shift in understanding about what is possible – that Australia can compete – in high value products and using innovative processes. And we can win.”

As the world becomes the market, Australia will enjoy a “greater ability to co-locate research, design and manufacturing, accelerating the innovation process,” Pollaers said.

For Australia, the most significant opportunities are in B2B – in high value products and processes.

Digitally connected safety equipment in manufacturing, for example, or in remote mining technology, and also in the convergence of the life sciences with the data sciences.

Industry 4.0, a fourth industrial

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INSIDE THE INDUSTRY: NMW 2017

Kawasaki welding robot demonstrates the effects of shielding gases on welding arcs.

revolution, places the world on the cusp of more significant change than we have ever seen before. The basic principle is that by connecting machines, work pieces and systems, businesses are creating intelligent networks along the entire value chain.

“The remarkable technological developments of the recent past will be dwarfed by this next generation of change. In 10 years’ time, the number of machine-connected devices will be at least three times the number of human-connected devices,” said Pollaers.

“The idea of 50 billion plus connected devices – and the question of how companies can leverage that technology – is reshaping the way global companies are thinking about their businesses.

What we are seeing is not only product and process transformation, but business model transformation.

That is the difference between this period in our technological and digital history and earlier watershed moments.”

This positive outlook was echoed by a number of leading industry speakers, including: Dr Jens Goennemann (Managing Director of the Australian Manufacturing Growth Centre) who discussed the Centre’s Sector Competitiveness Plan; Dr Keith Mclean (Managing Director of the CSIRO) who presented a road-map for unlocking future growth opportunities in Australian manufacturing; and BOC’s Peter

Kuebler who spoke on the topic of robotic welding and cutting in the mining industry.

Exhibition Director Robby Clark said the team had received positive feedback which, paired with the strong 2017 results, signalled an optimistic outlook for visiting industry, business owners and investors.

“We are thrilled with the 2017 results, which have certainly been one of the biggest years on record for National Manufacturing Week in Australia,” said Clark. “It is encouraging to hear many of our visitors, exhibitors and speakers view NMW as an event to mark in the calendar, with some already signed on for 2018 and beyond.”

Preserving Public Safety Through Compliant Fabricated Steel During NMW, the WTIA’s Chief Executive Officer, Geoff Crittenden, chaired a very well-received panel

Peter Kuebler gives a live demonstration.

discussion on ‘Preserving Safety Through Compliant Fabricated Steel’.

Panel members included Peter Milligan (Chief Executive Officer of AINDT) and Ian Cairns (National Manager - Industry Development and Government Relations of the Australian Steel Institute).

The discussion highlighted several alarming examples of unsafe fabricated steel, from multiple bridges in Western Australia, through to major landmarks, such as the Melbourne Star Observation Wheel. All of these projects exhibit similar problems: non-conforming steel, erected structures that do not comply with the original designs, and extremely poor quality welds. More often than not, these issues arise when the steel has been manufactured overseas and imported into Australia.

To help combat these issues,

Preserving Public Safety Through Compliant Fabricated Steel Panel. L to R: Ian Cairns, Geoff Crittenden and Peter Millligan.

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AUSTRALIAN WELDING | JUNE 2017

the WTIA, ASI and AINDT made submissions to the Senate Economics References Committee’s inquiry into the future of Australia’s steel industry.

“It’s a simple solution to stop substandard fabricated steel products being imported. We just need government support for a regulated scheme.”

In addition, a new Australian Standard was released: AS 5131 Fabrication and Erection of Structural Steelwork. The standard requires that engineers specify a steel fabrication Construction Category to confirm the correct level of quality and assurance controls required, thereby ensuring the structure meets the engineer’s design assumptions and mitigates safety risks.

Joining the Defence Global Supply Chain

However, according to the panelists, unless the Government legislates that Australian Standards are compulsory, and implements a rigorous system of compliance, public safety will remain at risk.

“The Government needs to draft legislation to mandate that imported, fabricated steel must be certified to Australian Standards before it can be erected,” said Crittenden. “The law is vital to ensure public safety and will establish fair competition for Australia’s fabrication and steel industry.”

In conjunction with Greg Keen (SEA 5000 Supply Chain Manager at Navantia), Julian Bende (Program Manager - Australian Industry Participation at Rheinmetall Defence) and Miles Kenyon (Program Development Manager at DMTC), Geoff Crittenden was also part of another extremely successful NMW presentation: Joining the Defence Global Supply Chain.

The Commonwealth’s $90 billion investment in Defence equipment and emphasis on Australian Industry Content has created a unique opportunity for SMEs to join the Defence global supply chain.

Through its Defence SMART Group, WTIA has been working with global shipbuilding and armoured vehicle prime contractors to look at what it takes to participate on a national and international level. This presentation delivered practical advice on how

Australian SMEs can access the global supply chains of Defence prime contractors.

According to Greg Keen, Navantia is looking for global supply chain growth, and is willing to invest in Australian companies to help deliver this growth. Navantia already has 300 years of shipbuilding heritage, so they are looking for new ideas and innovative Australian products that can deliver real value and long-term sustainment in Australia’s shipbuilding sovereignty.

Similarly, Australian industry content is an imperative for Rheinmetall.

According to Julian Bende, this is reflected in Rheinmetall’s focus on partnerships with local companies as their presence in the Australian market continues to grow.

Rheinmetall has agreements in place with Australian suppliers for work on the Land 1213B program valued in the hundreds of millions of dollars, while its activities around the Land 400 project have involved engagement with over 350 Australian companies during the bidding process. In areas such as munitions and the development of protection

INSIDE THE INDUSTRY: NMW 2017

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WTIA and DMTC Collaborate to Support Australian Welders The Welding Technology Institute of Australia (WTIA) and the Defence Materials Technology Centre (DMTC) have signed a collaboration agreement designed to support Australian welders, as well as small-tomedium enterprises.

Under the agreement, the two organisations will work together to develop a broader understanding of existing technology footprints and build a program of benchmarking, capacity building, training and certification activities. In particular, the WTIA and DMTC will help build industry capacity in areas of Defence priority, such as the welding of highstrength steels.

L to R: Geoff Crittenden (WTIA CEO) and Dr Mark Hodge (DMTC CEO).

systems, Rheinmetall is also building partnerships with local companies with a strong presence in these markets and high quality expertise. Bende encouraged Australian companies to get involved in Defence industry projects, particularly as Rheinmetall actively provides advice to local SMEs on the tender process, links SMEs with Austrade, and provides a range of other support services.

Miles Kenyon discussed DMTC’s Industry Capability Development Program, which aims to create a network of ‘Defence-ready’ companies with benchmarked, globally competitive capabilities. The program aims to foster collaboration between local SMEs and also build a critical mass of local capability that can be presented to prime contractors for major Defence projects.

This is ultimately about enhancing Defence capability but, significantly, is also about building industrial capacity in regions across Australia.

Building on previous capacity-building successes in areas such as CNC machining and additive manufacturing, current efforts focus on enhancing the welding capabilities of companies wishing to enter into Defence industry supply chains. The program includes benchmarking, as well as skills and technology transfer opportunities.

The welding and fabrication program, which began in Victoria’s Latrobe Valley, has been extended into new programs in Mackay, Queensland, and Illawarra, New South Wales, with planning underway to run similar programs in South Australia and Tasmania this year.

According to WTIA Chief Executive Officer, Geoff Crittenden, “Together with DMTC, the WTIA will help Australian welders, suppliers and contractors embrace new technology, upskill the workforce, and gain a deeper understanding of the requirements of Defence industry primes.”

“Governments at all levels are becoming increasingly aware of the potential shortfall in qualified welders that will be required to deliver the Commonwealth’s ambitious $100 billion Defence equipment programs.”

“The WTIA is committed to ensuring that all new Defence equipment is built by Australian welders and that Defence contractors have no reason or excuse for importing skilled labour to deliver these projects,” said Crittenden.

WTIA Chief Executive Officer Geoff Crittenden, and his counterpart at DMTC Dr Mark Hodge, signed the collaboration agreement at National Manufacturing Week in mid-May. According to DMTC’s Chief Executive Officer, Dr Mark Hodge, “Our work continues to focus on delivering a beneficial outcome first for our Defence customer, and for our industry partners. In that context, DMTC has already helped many Australian suppliers to embrace new technologies and better understand Defence requirements.”

“Formalising our relationship with WTIA will help us to share information on technology development,” said Dr Hodge.

Under the agreement, both organisations will also work closely with the Centre for Defence Industry Capability (CDIC), the establishment of which was one of the key announcements in the 2016 Defence Industry Policy Statement.

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AUSTRALIAN WELDING | JUNE 2017

Standards Update: ISO

Sub-Committee Meetings A number of ISO sub-committees and working groups met in Berlin, Germany in May. Australia was represented at several of these meeting by the WTIA’s Technical Publications Manager, Bruce Cannon.

Bruce represented Australia at three key meetings: TC-44 Sub-Committee 10, TC-44 Sub-Committee 11, and TC-44 Sub-Committee 11 Working Group Two.

ISO TC-44 Sub-Committee 10, responsible for Quality management in the field of welding, specifically the publication of ISO 3834 Quality requirements for welding, discussed a number of items of interest to Australia.

ISO standards utilise an arc efficiency factor in the calculation of pre-heat. These factors vary between welding process and range in value from 0.8 to 1.2, based on the submerged arc welding process having the value of 1.

Work was presented to SubCommittee 10 that questioned the current values used throughout Europe. It has been found that joint profile and cooling rate can have an influence on these factors.

The results presented will soon be released to industry, and it is expected that they will be reviewed by the same WTIA expert working group that is currently revising the WTIA’s Technical Note 1: The Weldability of Steels.

Australia has a simple, reliable system for the determination of pre-heat,

which is unlikely to change. It is a reminder though that, should a steel manufacturer provide an alternative method of pre-heat determination for the welding of its steels, their advice should be followed.

Also discussed by ISO TC-44 Sub-Committee 10 was the recently completed draft of the weld procedure qualification standard ISO 15614-1 Specification and qualification of welding procedures for metallic materials, currently at the FDIS (final) stage. Introduced in this draft is the concept of A

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INSIDE THE INDUSTRY: AUSTRALIAN STANDARDS

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ISO Standards are developed by committees comprised of technical, business, academic, and government experts who debate how a product or system should perform and how it should be made.

Before finalisation, every ISO Standard is subject to public comment.

change in welding power source as an essential variable, specifically relating to waveform controlled power sources. It only applies where these power sources are used in waveform controlled mode.

AS/NZS 1554 Structural steel welding touches on this through item (q) in Table 4.11(A) of Part 1, for example.

Of specific concern to ISO is the reliability and method of measuring amps and volts used by welding personnel to calculate pre-heat requirements and control the welding process when utilising these waveform controlled machines. In light of the ISO provisions, Australia may need to review its current requirements.

Australia asked ISO TC-44 SubCommittee 10 for an interpretation on whether ISO 3834 Quality requirements for welding is a quality management system.

The committee advised that ISO 3834 was developed to support and complement existing quality management systems, and to provide guidance to users of welding technologies on process inputs that need to be controlled to ensure

quality welding outputs. As such, it is permitted to be called up in a mandatory manner, with 24 ISO standards now referencing this suite of standards.

Following on from the SubCommittee 10 meeting, its Working Group 5 met to consider public comment on the revision of ISO/DIS 15612, which describes the qualification and use of Standard Welding Procedures (SWPs).

The concept of SWPs in ISO and elsewhere (such as proffered by the American Welding Society) is not new. While the concept is not widely referred to in Australia, SWPs are included within clause 4.4 of AS/NZS 1554.1 - Portability of welding procedures.

It is likely that in future revisions of the AS/NZS 1554 series, consideration will be given to the expansion of the concept of SWPs given the prevalence of companies in Europe who qualify and sell SWPs to fabricators, as well as the use of similar procedures though the American Welding Society’s B2 series.

ISO TC-44 Sub-Committee 11, responsible for Qualification requirements for welding and

allied processes personnel, and its Working Group 2, met over two days to resolve public comment relating to the circulation of ISO draft ISO/DIS 14731 Welding coordination - Tasks and responsibilities, and to consider comments relating to the five year review of ISO 9606-1 Qualification testing of welders Fusion welding.

In relation to ISO/DIS 14731, whilst most comments were resolved, it was apparent that further work is required to resolve some significant issues.

Regarding ISO 9606-1, the ballot results reconfirmed ISO 9606-1 for a further five years. However, comments received during the systemic review have demonstrated that a minor revision is needed to further improve the document and clarify areas of uncertainty.

Standards Australia currently has active projects to adopt ISO 9606-1 and amend AS/NZS 2980 to align with ISO 9606-1 requirements.

The next meetings of SubCommittees 10 and 11 have been scheduled for February 2018 in Miami, Florida (USA), hosted by the American Welding Society.

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AUSTRALIAN WELDING | JUNE 2017

Strategic Planning for the

New Financial Year The new financial year ushers in new, untapped opportunities. The key to capitalising on these opportunities, and taking your company to the next level, lies in creating an effective strategic plan. A strategic plan should guide your operations and decision-making process throughout the year, ensuring that the mission, vision and goals of your business are delivered upon.

The internationally renowned academic and author on business and management strategy, Henry Mintzberg said, ‘Strategy is a pattern in a stream of decisions’.

While the new financial year can be an exciting time, it can also cause considerable consternation around the sheer volume of decisions that must be made. A well thought-out strategic plan allows you to organise all the decisions that must be made into an easily digestible pattern, making them much simpler to implement.

The beauty of a strategic plan is that it creates the unity of thought and action that is so crucial to a successful enterprise—it offers a clear, concise run sheet that every member of your team can work towards. Your plan should, essentially, become a strategy map that charts the direction of the next 12 months, how goals will be achieved along the way, and how the ultimate purpose of the plan will be delivered on time, and on budget.

Another expert in business strategy, Jeroen De Flander said, “Don’t fool yourself: having a strategy map is not the same as having a strategy”.

Here’s how you can turn your map into an actionable strategy that delivers real world results.

Planning Meeting

Mission, Vision and Values

A planning meeting is integral to successful strategic planning. A successful meeting will involve all key decision makers and stakeholders. While it may take some preparation to assemble all the key figures in one place at the same time, it will be well worth it— you’ll be able to combine everyone’s ideas into one succinct plan. And, with contributions from all key stakeholders, company-wide buy-in should be assured.

If your company was established some time ago, there’s a chance that your original mission, vision and values are no longer relevant in the current economic and industrial landscape. Relevant, up-to-date mission, vision and values are integral in uniting your team and engaging customers.

Your planning meeting must be future-focused. Don’t waste valuable time rehashing the activities of the previous year. While a small portion of the meeting should be devoted to reviewing the existing state of the business (particularly any pressing problems), as soon as this initial review is finished, the remainder of the meeting should be aimed towards setting down a plan for the future.

Consider holding the meeting away from your regular workplace.

A change in location will remove decision-makers from the pressures and day-to-day distractions of the work environment, allowing them to focus solely on the task at hand.

When choosing a venue, don’t opt for style over substance. You need results, which means you need the right facilities: fast internet, projectors, refreshments, and so on.

When reviewing your mission, vision and values, ensure that they are all ‘lived’—that they are present in the day-to-day operations of your possible—or that they can be ‘lived’ if you choose to do so. Your mission, vision and values should not be aspirational ideas.

Aspirational ideas have a time and a place, but they can quickly become mere symbols, instead of serving as a point of inspiration for your team. You need to ensure that your employees are aware of your mission, vision and values and that they are still part of the fabric of day-to-day activities.

Value Drivers Your value drivers are the measurable markers of your company’s activities.

The most common value drivers are the promises that your brand makes to customers, and how your company derives profit from delivering on these promises. These value drivers need to be central to

INSIDE THE INDUSTRY: BUSINESS ESSENTIALS

your strategic plan. This may mean that you need to review your value drivers, particularly how effectively they are being implemented, managed and reported on.

Customer Base Your strategic plan must take into account your current customer base, your future customer base, how you will increase customer retention, and how you will seek out new customers. You may find that certain sections of your customer base aren’t aligned with your strategic plan. This means that your company might be better off not pursuing that customer base, and instead seeking out a new customer base that will allow you to achieve your goals.

Employees Employees are obviously central to your ability to achieve the goals set out in your strategic plan. As such, your strategic plan needs to contain processes that can be used to arm your company with the right people.

To do this, you will need to review current employees, as well as your hiring and retention processes.

Strengths, Weaknesses, Opportunities and Threats (SWOT) Analysis A good strategic plan will take into account the strengths and weaknesses of the company so

that it can capitalise on strengths and improve weaknesses. A SWOT analysis will also allow you to assess your company’s ability to respond to external pressures (such as economic downturn, or new regulations), whilst remaining true to your mission, vision and values.

Be Prepared to Invest There’s no way to avoid the fact that you’ll have to pay to achieve your goals. In fact, devoting money to your strategies, and including this spend in your budget, demonstrates your commitment to your strategic plan. A strategic plan must extend beyond mere symbolic status. By understanding the financial impact of your strategies, and including this in the plan, you give your plan the best chance of being successful.

Accountability and Buy-In A strategic plan is a useful tool in aligning your team behind a common goal. But, before this can be achieved, you have to unite your team behind the strategic plan.

The only way to get a team to buy into the plan is to communicate.

Communication should be centered on making key players accountable for various aspects of the strategy.

To make various players accountable, you need to break the strategy down into specific sections, with the most relevant department accountable for

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actualising each section.

To maintain enthusiasm and improve buy-in, break over-arching goals down into sub-goals. If everyone is striving towards one goal that will take years to achieve, over time, the enthusiasm for reaching that goal will erode. If you set smaller goals that can be achieved in mere months, it gives your team something to tick off before they move onto the next goal.

The Dangers of Personal Goals When creating goals in your strategic plan, ensure that you’re not too insular in focus. Personal goals based solely on the operations of your business run the risk of being irrelevant. Goals should always be constructed in reference to your competition, the current state of the economy, and future trends in the industry. Remember, nothing exists in a vacuum—your goals and strategic plan must be grounded in reality, or they simply won’t be achievable.

Consistency in Delivery After a strategic plan has been created, leaders need to be proactive in consistently enforcing the direction of that plan. A strategic plan is only as good as its implementation.

Consistency is key to ensuring that every member of the team is performing the day-to-day tasks that will ensure the fulfillment of the plan’s overarching goals.

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AUSTRALIAN WELDING | JUNE 2017

Five Welding Safety

Hazards to Avoid Welders are exposed to both physical and chemical hazards in the course of their work. The techniques and tools used have the potential to cause severe injuries, particularly to the eyes, as well as result in chemical exposure, and electric shock. To avoid the illnesses and injuries associated with these hazards, employers need to implement proper workplace health and safety controls and systems, as well as thorough employee training. Awareness of the most common welding hazards and how to avoid these hazards ensures a safe, productive working environment for all.

Chemical Exposure Welding joins materials together by melting a metal work piece along with a filler metal. The welding process produces visible smoke that contains harmful metal fume and gas by-products. The inhalation of these chemicals may cause irritation to the nose, throat and eyes. Repeated exposure, over a long period of time, can have serious health effects, including damage to the lungs and kidneys, and even cancer.

To avoid exposure to chemicals Personal Protective Equipment (PPE) must be worn at all times. In addition, the proper engineering controls (such as local exhaust systems) must be implemented to ensure sufficient ventilation throughout the welding workshop.

Welders must also pay attention to their environment. If at any point during welding breathing becomes difficult or uncomfortable, welders must leave the area immediately and check that the local exhaust is working. This is especially important when welding with stainless steel or hardfacing products.

To prevent chemical exposure from coatings such as paint, galvanizing, or metal platings on base metals, welders should clean the base metal prior to commencing the weld.

Eye Injuries PPE is vital in protecting welders’ eyes from damage as a result of sparks and vapours. Welding helmets will protect welders’ eyes

but anyone standing near the welder needs to be protected as well.

materials within the work area, if you can’t remove them.

Fire and Explosions

Electric Shock

A welding arc can reach temperatures of up to 5,530°C. The arc itself isn’t the danger, but the sparks and spatter generated by the arc can be flung up to 10m away from the arc, creating fire and explosion hazards.

Perhaps the most serious risk faced by a welder, electric shock commonly occurs when a welder touches two metal objects that have a voltage between them. Welders need to be wary of what they touch—the simple act of picking up two wires can lead to electrocution, serious injury and even death.

To mitigate fire and explosion risks the welding area needs to be thoroughly inspected before the weld begins. All flammable and potentially explosive materials need to be moved as far away from the area as possible.

Items to look for include petrol, paint, oil, wood, paper and gases, such as hydrogen and acetylene.

Workplaces also need to make sure that there are proper emergency procedures in place to deal with a fire or an explosion. Fire alarms and extinguishers need to be checked regularly and all staff need to be aware of the nearest exit and emergency evacuation procedures.

If a job requires the welder to be within 10m of flammable materials, a supervisor needs to be present to monitor where sparks land, keeping an eye out for smouldering embers.

The area needs to be monitored for at least 30 minutes after the weld is completed to ensure smouldering embers do not become fires.

Place fire resistant material, such as a piece of sheet metal or fire resistant blanket, over any flammable

Another type of electric shock is secondary voltage shock, which originates in the arc welding circuit.

This shock can range from 20 to 100 volts. Given that a shock of less 50 volts is enough to kill a man, this is very serious.

Welders need to wear high-quality dry gloves to prevent electric shock and ensure that they never touch the electrode holder, or the electrode itself, with anything that is wet. They also need to be insulated from the ground and the work itself.

Before starting a job, welders need to inspect the electrode holder and make sure it isn’t damaged. The welding cable also needs to be in good condition. The most important thing to check for is that the fibre or plastic insulation is in good condition. This insulation provides protection from the electrified metal parts inside the system. It’s incredibly important that welders remember stick electrodes are always electrified.

INSIDE THE INDUSTRY: HEALTH & SAFETY

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Primary voltage shock—the most electric shock—can occur if a welder touches the electric distribution system that powers the welder or if they touch the inside of the welder case. Contact with either can result in a shock of 230 to 460 volts.

Radiation Burns A serious hazard, radiation burns are caused by the ultra-violet radiation that stems from electric welding arcs. The only way to protect against radiation burns is to wear PPE that is in perfect condition. At a minimum, flame proof gloves, aprons and long-sleeve shirts need to be worn and welders need to resist the temptation to roll up their sleeves.

What is Appropriate PPE? Helmets: Helmets with a side shield are necessary to protect the eyes and skin from exposure to harmful elements. Different shades of lenses are required for different types of welding so make sure the appropriate one is fitted. Safety glasses with side shields should also be worn underneath helmets.

Boots: Leather boots with sufficient ankle coverage are a must. Metatarsal guards can also be worn over shoe laces to prevent hot splatter entering boots, and to protect against falling objects. Boots need to have rubber soles to insulate the welder from the ground.

Gloves: Gloves need to be flame-resistant and heavy enough to protect against cuts, burns and electric shock. Leather is the best material.

Ear Protection: Ear muffs should be worn to protect against metal debris and burns, and industrial deafness. For extra protection, put ear plugs in first.

Other Considerations Welders should be aware of other safety considerations within the work environment. For example, those working in a confined space or in an elevated area make need to take extra precautions. Welders should also pay close attention to safety information on the products being used and the material safety data sheets provided by the manufacturer. Above all, welders must work with their employer and co-workers to follow appropriate safe practices for their workplace.

Image courtesy of Lincoln Electric.

If common sense is used and all safety precautions are followed, welding is a perfectly safe occupation. Accidents happen when rules and regulations aren’t followed and corners are cut.

The consequences are too severe for workplace safety to be ignored. Make sure your workplace follows safety protocol every day, for every job.

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AUSTRALIAN WELDING | JUNE 2017

Welding Accuracy

Control In Shipbuilding Shipbuilding involves the fabrication of large and complex welded structures. Hulls are made up from many plates joined by buttwelding with bulkheads and stiffeners welded to the inside surface only. The trend to block construction enables high levels of fit-out to be completed with minimal access restrictions. Piping and other services within each block must be fabricated with high accuracy to enable efficient integration into the structure.

Maintaining accuracy in overall dimensions of sub-assemblies is critical to the success of shipbuilding.

The current trend is to optimise designs using thinner plates and lighter stiffening creates greater challenges in accuracy control.

Accuracy Control Concepts The purpose of metal fabrication is to create the form, physical characteristics, and finish of a metal component according to clearly defined specifications. The fabrication process is executed by a group of people using available technologies and procedures. A measure of the effectiveness of the fabrication process is the ability to correctly produce specific parts that meet the specification. Welding accuracy is therefore the difference between the achieved mean dimension and the target specification.

Sources and Control of Variation In order to achieve accuracy in the fabrication of ships, all sources of variation must be identified.

A holistic approach to the manufacturing process is required in this identification—one which integrates both product and process knowledge. All steps involved in design and manufacturing that can impact on accuracy must be pinpointed, with process control measures put in place for each step.

Drawings Drawings in electronic format are

increasingly being linked directly to marking out and cutting operations.

This reduces the potential for errors and enables rapid feedback of systematic non-conformances in marking out and cutting. Minor changes to electronic drawings can be made to tailor the drawing to the manufacturing process or even individual production machines.

Precision in Marking Out and Cutting Modern shipyards are utilising CAD or CAM in their laser and plasma cutting operations. The same equipment is now increasingly used for component identification and marking out. Marking out for subsequent assembly as part of the CAD or CAM cutting process minimises subsequent requirements for marking out, greatly reduces errors in marking out and improves assembly times. This enables: • High accuracy in cutting leading to good fit up in the fabrication shop, resulting in less minor corrections and accompanying distortion. • Identification of parts and marking out of cut pieces using dot matrix, laser or plasma systems.

This leads to greatly enhanced traceability of parts, enhanced precision of assembly, thus minimising errors and rework.

Precision in Weld Preparation Preparation of bevels for plate butt welds is now commonly performed by machining. While machining

is more expensive than thermal cutting, it enables compound bevels to be produced with precision not achievable by thermal cutting processes. Extremely accurate fitment of parts to be joined can be achieved. This is particularly important for larger welds such as main plate butt welds where major gains can be made in controlling overall distortion.

Precision in Assembly This is where it all comes together.

Precision in assembly is dependent on accuracy of design, accuracy of cut parts, accuracy of marked assembly lines and, last but not least, the skills of the people undertaking the assembly.

Tack Welding Tack welding plays a critical role in holding the assembled structure together ready for welding, as well as in maintaining correct root gaps in butt welds and preventing movement

INSIDE THE INDUSTRY: WELDING ACCURACY CONTROL IN SHIPBUILDING

21

For more information, refer to the WTIA’s Technical Guidance Note Three: Accuracy Control in Shipbuilding, available via www.wtia.com.au Stiffening Stiffening of a structure can be achieved in a number of ways.

Use of larger tack welds, partially welding, provision of temporary bracing, use of assembly jigs with preset camber can be used to minimise distortion of a weldment.

Longitudinal stiffeners welded along each side of a long seam can be used to prevent bowing of long members.

Stiffener location is also important.

If stiffeners are too far from the joint they are stiffening they may be ineffective, whereas if stiffeners are too close they may interfere with welding of the joint.

in the structure as welding progresses.

The number of tack welds, the length of the tack welds, and the distance between the tack welds will depend on the length and thickness of the weld, the degree of rigidity needed, the details of the weld preparation and the welding process being used. The tacking sequence can also have an effect and may need to be controlled to ensure correct root gaps are maintained along the length of a joint.

Back-To-Back Assembly Back-to-back assembly of identical asymmetrical structures provides a method of counteracting the shrinkage forces of one component with the shrinkage forces of another. Additional presetting may be required so that when the two components are freed from each other there is no residual distortion due to spring back from locked up residual stresses.

Pre-Setting Where a known amount of angular distortion will occur, presetting the joint by the amount of angular distortion expected ensures the alignment of the finished weld.

This method can be very effective if consistent shrinkage rates are achieved through close control of welding procedures.

Jigs and Fixtures Jigs and fixtures can be used for assembly and welding of subassemblies where the components are held rigidly until welded. This approach works well for production of multiple smaller sub-assembles.

Welding Process Higher energy processes that allow higher welding speeds generally lead to lowering of shrinkage and distortion rates with the advantage of increased welding productivity.

Implementation of processes enabling higher welding speeds may be difficult to justify solely on the basis of reduced welding time, but overall savings can be significant

when the downstream costs of distortion correction are considered.

Controlled Welding Procedures Ensuring all operators are following welding procedures ensures that weld metal shrinkage is consistent.

Maintaining consistency in shrinkage outcomes requires good welding management systems. Welding procedures should be developed to ensure that minimal weld metal is deposited while maintaining the specified weld quality level.

When carrying out the fabrication it is important that the weld sizes are produced within the specified size range and weld shape is correct.

Over-welding of thin structural sections is common, although there is no advantage to the fabricator or customer in over-welding. Under-size welds can lead to costly re-work with inevitable increased distortion.

Welding Technique General rules for minimising distortion: • Keep weld volumes and size to the minimum specified • Balance welds about neutral axes • Keep the time between runs to a minimum • Maintain pre-heat temperatures Welding Sequence The direction and sequence of welding is important in distortion control. Generally welds are made in the direction of free ends. For longer welds, back-step welding or skip welding should be used. For backstep welding, short weld lengths are placed with welding in the opposite direction to the general progression.

For skip welding, a sequence is worked out to minimise and balance out shrinkage stresses.

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AUSTRALIAN WELDING | JUNE 2017

Tips & Tricks for

Welding Titanium Titanium is a popular material choice for many industries, particularly defence and aerospace: it’s 40% lighter than steel but offers 30% (or better) strength to weight ratio; it is highly resistant to corrosion; it has low expansion and thermal conductivity; it can operate at temperatures of up to 280°C; and it has far greater stiffness than magnesium or aluminium. While titanium is more expensive than other options initially, it is more cost-effective over the entire lifecycle. This is mostly because it is incredibly long-lasting and requires little to no maintenance once installed. However, titanium does have some less desirable characteristics that must be addressed during welding.

Many of the less than optimum qualities of titanium directly affect welding, resulting in it getting a reputation as being difficult to work with. At high temperatures, titanium becomes highly reactive to chemicals in its environment. In regular air, welding contaminates titanium with carbides, nitrides and oxides that make the weld and HAZ (Heat Affected Zone) brittle, resulting in lower fatigue resistance and notch toughness.

In addition, chlorine from sweat or cleaning compounds can create corrosion on the weld. Thus, the weld and its back side must be protected from contamination.

Even friction from grinding wheels (especially aluminum oxide wheels) can develop enough heat and provide the contaminants to undermine the weld. Even given these considerations, with careful preparation, any professional welder can obtain quality titanium welds.

Creating the Perfect Environment To overcome some of the weaknesses inherent in titanium, preparation of the welding environment is key. Thorough preparation will help ensure the weld isn’t affected by chemicals in the environment, made brittle by air reacting with surrounding oxides, nitrides and carbides, or corroded by the chlorine in cleaning compounds and sweat.

As contamination is a huge factor

in titanium weld quality, the welding environment must be completely clean before welding commences.

This includes removing all moisture, grease, dust and any other contaminants. All air entry points must also be sealed. Some welders even opt to set up an area that is designated exclusively for welding titanium, if this sort of work is a regular occurrence.

Never use steel wool, sandpaper or a steel file to remove burn marks.

All of these will leave particles in the base metal. Instead, use a carbide file. If acetone or methyl ethyl ketone are used to clean the surface, make sure they have completely evaporated before an arc is struck.

Lint-free fabric wipes are the best way to remove any leftover residue or contaminants.

Preparing the Materials

Always use a hot air blower to remove moisture. Even if moisture isn’t immediately obvious, give the area a once over to remove invisible condensation. After the area is completely dry, titanium with light oxide scaling can be cleaned by using acid pickling.

The materials being welding must be completely clean before welding commences. Nothing can be contaminated by dirt, dust, grease or the oils in skin. Nitrile gloves should be worn while handling and cleaning the filler rod and all other parts.

Any contaminant introduced to the titanium during the weld will have a negative impact on its performance, longevity and ability to resist corrosion. So, joining surfaces must be clean and smooth, and weld joints must be completely cleaned and dried.

Preparing the Weld Surface When it comes to preparing the weld surface, only stainless-steel brushes should be used. It’s important that a specific brush is designated for titanium. This minimises the chances of cross contamination. This brush should be properly maintained—it should be regularly rinsed in alcohol and stored in an airtight container.

All weld joints that aren’t going to be welded immediately after cleaning need to be covered with plastic or paper to prevent recontamination.

Grinding Titanium The introduction of contaminants is still a concern when grinding titanium. For this reason, only carbide grit wheels should be used, and grinding should be performed slowly and gently. If the temperature of the titanium reaches above 260°C, scaling can affect the surface of the material.

Completing the Weld After all that preparation, it’s finally time to complete the weld.

INSIDE THE INDUSTRY: TIPS FOR WELDING TITANIUM

The first thing to focus on is shielding the HAZ (Heat Affected Zone) and the root side of the weld from air to prevent oxygen contamination.

Pure argon is the best type of shield gas, although for high performance applications, cryogenic argon should be used. The argon needs to be 99.999% pure to prevent discolouration. If you see any blue tinting on your weld, it means that the argon contains impurities.

Quality tungsten electrodes are essential to a quality weld and you also need to be careful to only grind them on a dedicated grinder and to complete this grinding away from the welding environment.

Test supply hoses, leads and fitting for leaks and make sure all O-rings and torch insulators have a proper

seal and fit. If the titanium is heated to over 400°C, clamps and fixtures could contaminate the titanium.

Maintaining a gas shield on the backside of thinner material is a must if heat is an issue. If you’re dealing with smaller parts, try to use a glove box that has been filled with argon. For larger parts, invest in polyethylene purge gas chambers.

Always use an oxygen sensor to check that the gas shield is working.

Wherever possible, attach a trailing shield to the trailing side of the TIG torch. This extra shielding will be essential in protecting the molten weld puddle.

When adjusting the gas flow, ensure that there is optimum coverage and torch cooling, while still preventing turbulence. A 25.4mm nozzle fitted

with a gas flow straightener is best, and the argon flow should be started several seconds before welding to ensure proper coverage. Keep the protective argon flow going until the titanium has cooled to below 260°C. The use of too much argon can result in swirled or mottled patterns in welds. Uniformity in colour indicates correct shielding. Discolouration doesn’t always necessarily equate to a poor weld, but each step of discolouration (straw, brown, purple, blue, dull salmon pink, and grey with oxide flakes) indicates a further severity of contamination.

As a rule, a little blue discoloration in certain applications is acceptable.

On the welded side, light straw and even brown discoloration can be passable, depending on the criticalness of the weld.

Titanium Welding Essentials 1.

2.

3.

4.

5.

6.

7.

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Ensure the work area is completely clean and sealed off.

Ensure all surfaces and materials are clean and contaminant free.

Perform grinding slowly and gently.

Use only 99.999% pure argon gas.

Shields must be well maintained and gas evenly distributed.

Always use high quality tungsten electrodes.

Keep the argon flowing until titanium has cooled to below 260°C.

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AUSTRALIAN WELDING | JUNE 2017

Australia’s Advanced

Manufacturing Council Established in 2013, the aim of the Australian Advanced Manufacturing Council (AAMC) is to drive industry and policy change to foster Australia’s comparative advantages in advanced manufacturing.

A CEO-led private sector initiative, the AAMC brings together industry leadership to bolster innovation success, as well as resilience within the Australian economy. AAMC is focused on making Australia truly competitive on the international scene, specifically in its ability to provide an attractive location not only for Australian industry to thrive in but also to attract international advanced manufacturing businesses, and innovative businesses more widely.

According to Chairman of the AAMC John Pollaers, global manufacturing is undergoing not only product and process transformation, but business model transformation as industrial firms adjust to the digital age. “That is the difference between this period in our technological and digital history and earlier watershed moments,” said Pollaers.

“There are certainly changes occurring in process and product technology. For example, Caterpillar might consider the question, ‘How do you make a tractor?’ But the hype – the substantial change we are seeing – is in the question ‘How do you sell a tractor as a service?’”

While still a minor player in global production sharing, Australia has a competitive edge in parts and components specialisation in several product categories, including aircraft parts and associated equipment, parts of earth moving and mineral processing machines and specialised automotive parts.

The achievements of Australian manufacturing in the new dynamic areas of global production sharing have done much to dispel the prevailing perception of the ‘death of manufacturing’ in Australia.

The fact is that many Australian manufacturers are not only surviving, but prospering.

“A recent study from the Office of the Chief Economist has validated what

the AAMC has been arguing for the past four years.”

Building a Forward-Looking Nation

“This gloomy perception of manufacturing – aside from being false – has created a hurdle for manufacturing firms to recruit and retain talent, to attract potential customers and to unlock potential opportunities by policy makers,” said Pollaers.

The Australian Advanced Manufacturing Council has commended the Government’s decision to fund the Western Sydney airport and a $10 billion national rail program, as well as its commitment to future skills development.

Australia has room for improvement in gaining access to export markets and the global supply chains of multinationals. The ‘tyranny of distance’ is not a binding constraint on exporting specialised parts and components, and some final assembly goods from Australia.

With advancements in technology, there is a greater ability to take lower value production closer to markets to optimise the production chain against factors like transport costs and local content requirements.

According to Pollaers, the big challenge is a concentration of funding around technologies where Australia has great prospects – where the investments will have impact. For example, in carbon fibre nanotechnology, and the digitalisation of manufacturing.

The government recently revealed a $75 billion decade-long infrastructure spending spree as the centrepiece of its economic growth plan.

“These measures are all about our national competitiveness,” said Pollaers.

Plans include $8.4 billion earmarked for the Melbourne to Brisbane inland rail link, $5.3 billion for Sydney’s second airport at Badgerys Creek and upgrades for Queensland’s Bruce Highway and Western Australia infrastructure.

Treasurer Scott Morrison promised $5.3 billion in equity over the next 10 years for the new airport. A Western Sydney airport will be a magnet for economic growth, Pollaers said, and this truly major airport on an international scale, with the proposed surrounding industrial and university precincts, will provide a much-needed decentralised hub for manufacturing for the future.

“I commend the Government for the courage and foresight to ensure that it happens,” said Mr Pollaers.

INSIDE THE INDUSTRY: AUSTRALIA’S ADVANCED MANUFACTURING COUNCIL

“Australian advanced manufacturers are achieving great things in the face of intense global competition. But the conditions are tough.”

“Right now, significant technological shifts are occurring in manufacturing: commercial applications for artificial intelligence and machine learning are expanding; we see robotics entering a new phase; significant advances are occurring in nanotechnology, 3D printing, genetics, biotechnology, chemistry and materials science.”

“The past two to four years have seen important changes not only in the way Australians think about manufacturing but in the way we see the world. There is a major shift in understanding about what is possible – that Australia can compete – in high value products and using innovative processes.

And we can win.” ~ John Pollaers, AAMC Chairman

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AUSTRALIAN WELDING | JUNE 2017

The inland rail and other rail initiatives would increase industry efficiencies and competitiveness and ensure we are less dependent on road freight, he said.

“We would urge the Government to plan for important technology developments like the Hyperloop, and for self-driving mobility, while they are evolving these infrastructure programs,” said Pollaers.

“New airports and rail corridors are the perfect greenfield to build these things in – a way to put Australian infrastructure at the forefront in the world.”

Meanwhile, the strong focus on skills development in the 2017-2018 Budget was a “measure of clear-headed foresight and appreciation of the need to build our competitive edge,” said Pollaers.

“Unless we have a strong underpinning of 21st Century skills and education, we will not attract the much-needed international investments. The biggest thing companies are looking for is the right talent. The key factor that will lead Australia into a diversified sustainable economic future is skills,” said Pollaers.

Other countries are doing similar things to Australia, but not all of them have the skills needed, he said.

The Government’s investment of $1.5 billion over four years from 2017-2018 to establish a permanent Skilling Australians Fund, was “an enormously important and critical measure.”

“We were very encouraged to see the focus on high value manufacturing in the announcement of $100 million for the Advanced Manufacturing Fund.”

According to Pollaers, this will do an enormous amount to support design and engineering, and Australia’s transition to greater global competitiveness.

An AAMC Success Story: Keech Casts Its Net Wide Stories of doom and gloom ignore countless Australian manufacturers who are not only surviving, but prospering, as they tap new areas of growth and take their innovations to global markets. Australia’s advanced manufacturers are transformative companies.

They are securing their own futures, creating jobs, and helping to underpin a sustainable Australian economy.

One such company is 83-year old Bendigo-based manufacturer Keech Australia. Keech is currently preparing to flick the switch on its new high tech production line, which incorporates the latest Industry 4.0 sensor and computer programming technology.

Built around information sharing and process improvements, Keech, which makes high integrity steel castings, believes it is introducing the world’s most efficient production line into its business.

“Our staff anywhere in the world can actually be watching this production line and manipulate it remotely,” said Keech Chief Executive Dr Herbert Hermens. “We already have systems now that can give transparency to our customers, but this takes it another step further.”

While the firm has been operating for eight decades and employs traditional foundry equipment such as arc and induction furnaces, Keech also embraces 3D printing and has built a design team with the brightest minds in the business.

“Some people looking from the outside into an organisation such as this see it as old technology and I can tell you it is far from that. The complexity is enormous,” said Hermens.

“Even a few degrees can ruin a melt. We have highly qualified engineers at the doctorate level working within the company to make it successful. We now have a very important 3D element in our company. So we think our company is in fact a high-tech business and I certainly treat it as such.”

Keech’s suite of various sized 3D printers make prototypes and moulds quickly, sometimes overnight, to demonstrate what a proposed part will look like to a customer. “There is a great appreciation for that immediacy,” said Hermens.

Keech offers ground engaging tools, tillage implements, rolling stock components and custom casting products.

Around 30% of revenue comes from mining, and the firm also services rail, construction, agriculture and defence.

Keech has grown exports dramatically from just 2-to-3 per cent of its business eight years ago to a “significant” portion today, selling to Japan, Europe, America, South America, South Africa and “all points in between.”

INSIDE THE INDUSTRY: AUSTRALIA’S ADVANCED MANUFACTURING COUNCIL

27

“This company could not survive just being a local supplier. So now we have a subsidiary in Chile and we have engineers who travel around the world working with our end-user customers. Our focus is truly on the global market, which reaps benefits for our domestic customers as well,” said Hermens.

“Our reputation does spread. We have been able to align ourselves with some very high-quality, key manufacturers elsewhere in the world and that allows us to build a partnership-type approach. They want to build a relationship and want us to be part of a design criteria and want us to understand their customers.”

According to Hermens, customer trust and going the extra mile is essential in order to beat out the competition. “You can’t just supply a widget. The moment you supply a widget the biggest hurdle for Australia comes into play – the cost. What we need to do is supply ‘more than.’ You don’t necessarily get any more money for it but what you do is reduce the focus on price,” said Hermens.

“That is certainly the key to Keech. Understanding what the customer, the manufacturer really wants from you and how you can improve that delivery. So then all of a sudden when you look into that supply chain it is very difficult to knock you back out again because it is not just about somebody making it cheaper than you. It is about somebody being able to replicate the quality of the supply package that you represent.”

The team is highly adaptable in a challenging world, where every relationship is “just slightly nuanced,” and many customers now are looking for more than just supply of “a thing”, which was adequate only ten years ago.

“We can no longer assume that if we supply a certain product of a certain quality in a certain time frame, that is enough. Customers are now seeking more and more and more and putting more responsibility onto suppliers.”

Dr Herbet Hermens, Keech Chief Executive.

What is Advanced Manufacturing?

Advanced manufacturing is a family of activities that (a) depend on the use and coordination of information, automation, computation, software, sensing, and networking, and/or (b) make use of cutting edge materials and emerging capabilities enabled by the physical and biological sciences, for example nanotechnology, chemistry, and biology. This involves both new ways to manufacture existing products, and especially the manufacture of new products emerging from new advanced technologies.

The Australian Advanced Manufacturing Council defines advanced manufacturers as globally-oriented and innovative manufacturers, in general sharing the following characteristics: • • •

High Intellectual Property component.

Dependent on global supply chains.

The only public sector support needed is at the Research & Development phase through tax credits or leveraging public-private partnerships.

Advanced manufacturers tend to be engaged in collaborations with universities, the CSIRO and other research institutes.

Advanced manufacturers sell to a global market and compete on distinctive qualities. The domestic market is not a constraint.

These manufacturers constantly innovate to remain competitive. They leverage the latest thinking in technology and materials.

They produce high margin products.

They have smaller capital and labour footprints but are higher paying, and provide higher quality work.

Keech’s own examples include introducing faster change-out times for a particular mining product to improve ease of use, as well as redesigning an 11-part product to four parts, greatly reducing welding as well as processing and attachment times.

•

“This saved money, secured Keech the customer and meant price was no longer such an issue because the service went beyond supplying a part,” said Hermens.

• •

“We have gone to a great deal of effort to understand the end user. In terms of quality I think we are equal to any other company you could point to anywhere in the world. That only happens when you put yourself out there and say we are prepared to come to you.”

Advanced manufacturers are involved in the development of new markets, new products, new technologies and new ways to manufacture existing products. The US definition of advanced manufacturing highlights not only the value of companies involved in emerging technologies, but innovations that improve processes and production.

•

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AUSTRALIAN WELDING | JUNE 2017

Engineering Solutions to

Erosion and Corrosion Headquartered in Perth, with a growing network of workshops in both Australia and overseas, Callidus Welding Solutions’ main 2,400m2 workshop is dedicated solely to non-ferrous metals and alloys. With significant experience in joining, rebuilding and overlaying corrosion and wear-resistant alloys for the mineral processing, power generation, marine and mining industries, their services extend from robotic and automated welding and fabrication of process equipment, through to repairs and maintenance of inservice equipment and surface engineering.

“We’re not your average welding and fabrication business,” said Gary Lantzke, CEO of Callidus Welding Solutions (CWS).

“Our company vision is to deliver engineered solutions tailored to our clients’ specific erosion and corrosion challenges. In saying that, our focus in recent years has been non-ferrous materials and highend, newer breed materials such as austenitic and martensitic stainless steels, high-temperature alloys like Inconel and Hastelloy®, and duplex, super duplex and titanium.”

“All of these materials have great corrosion resistance and operate well at high temperatures and in aggressive service environments. The problem is that some are quite soft and when they’re used in processes that feature really fast movement, they suffer erosion. So, for the last ten years or so, CWS has focused on how to improve the longevity of these materials,” said Lantzke.

Whether it’s a worn titanium feed pipe, a corroded super duplex valve body or a cracked Inconel injection stem, CWS has seen (and repaired) it all before. CWS has identified the root cause, proposed and undertaken repairs and developed welding procedures for countless fabrication and repair challenges.

It is CWS’ heritage of repair and maintenance of high-cost plant and equipment, and their ability to understand exotic metals

and the changes they undergo after operating in severe service conditions that gives CWS the unique ability to embark on innovative research.

“In our experience, designers and plant engineers often opt for materials that will suit a process, without actually knowing how that process will play out in reality. If the material selected by a plant engineer doesn’t work, it can be exceptionally difficult to repair or maintain.”

“For instance, duplex and super duplex are extremely difficult to weld over. Most hard-facing applications contain chromium alloys, and when you start adding chromium to chromium, cracking is much more likely to occur,” said Lantzke.

“This forms the basis of our research - how do you take parts of an alloy and add certain parts of other alloys, to create a hybrid alloy that offers optimum in-service performance?”

“In duplex and super duplex, we started with a high corrosion resistant matrix and added elements to improve its wear performance. We actually found that when some alloys precipitate, they turn into carbides that offer improved corrosion and wear resistance.”

“We’ve also been looking at how to get titanium to last longer. Many years ago, after a plant shut down, one of my customers said to me, ‘I just replaced every piece of

titanium in the plant, at a cost of over $400,000—it just isn’t viable long-term. Surely there has to be a better way.’ So we looked at whether we could purposely contaminate titanium to give it better wear performance. After all, when you weld titanium, it goes hard.

We figured there had to be a way to create a hard layer that was still serviceable,” said Lantzke.

CWS now has two titanium hardfacing robots working day in, day out. The titanium nitriding process can be manipulated to provide a specific hard-facing layer with 375 Vickers (HV) through to 900 HV and anywhere from 1mm to 10mm thick.

CWS is able to design titanium nitride coatings that are customised for specific items and processes.

Last year, CWS commenced a joint collaboration with AusIndustry and Deakin University, entitled ‘Towards the Optimisation of a Novel Titanium Surface Modification Process.’

“We are looking at how to take a process that we have already developed, make it tougher, and then apply it to other industries—not just industrial and mining—but military, marine and aeronautical applications as well,” said Lantzke.

“We completed stage one of the collaboration project with Deakin University last year - refining a process that CWS has been developing for years. We know the process works—we’ve trialled it insitu. Our clients were telling us that

INSIDE THE INDUSTRY: CALLIDUS WELDING SOLUTIONS

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Case Study: Wear Protection of HPAL Autoclave Internals The internal surfaces of HPAL Autoclaves are fully lined with a corrosion resistant layer of titanium. This cladding offers corrosion resistance but is prone to erosive damage at high slurry flow rates to areas of the autoclave that present a disruption to the product flow path.

The Problem: A high level of erosion is particularly evident on the Autoclave batten strips and comp pads, which typically suffer erosion of the retaining fillet welds.

The Solution: To reduce the rate of erosion, areas that are prone to erosive wear are coated (using an advanced thermal spray process) with a 300-500 micron layer of Titanium Dioxide with a typical coverage width of 70mm, allowing a minimum of 25mm each side of the fillet weld face.

“The results of stage one were so interesting that we couldn’t deny moving forward. The results gave us enough information to immediately strengthen and improve our product, and opened up discussions around how to introduce alloying to the titanium nitriding process to create a brand new process and alloy.”

According to Lantzke, more Australian companies must look towards innovation—as CWS has done—in order to survive, “To us, the standards and specifications are just a minimum level of acceptability. If Australian industry focuses on just bare compliance, we’ll be no better than our overseas competitors. Australia needs to focus on technological, high-end advancements, and on being better than just average.”

“We’re hopeful that the project will spawn two or three patents related to new overlays and surface engineering processes and products,” said Lantzke.

“If we do that, novel, inventive businesses will spring up that are able to offer their customers a real competitive advantage. That’s where Australian industry has to go.”

they wanted to use it so we knew the process worked, but we didn’t really know why.”

The Result: • Erosion reduction of titanium clad is 72%.

• The time frame for weld repairs inside the autoclave was reduced from 168 man hours to just 48 man hours.

• There has been no unplanned erosion breaches in 6 Years.

• The customer was extremely impressed with the performance of the applied TiO2 and have implemented trials in other areas of the clave to combat pit corrosion.

• TiO2 has also exhibited excellent results when applied to the wear areas of autoclave agitator blades.

For further information, contact CWS on (08) 6241 0799 or visit http://callidusgroup.com.au.

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AUSTRALIAN WELDING | JUNE 2017

State Focus:

South Australia Defence is a critical sector for South Australia’s economic prosperity, currently employing 27,000 workers and contributing approximately $2 billion to the state’s economy annually. The cornerstone of South Australia’s advanced manufacturing future, Defence creates long-term employment, attracts significant investment and drives innovation. South Australia is home to a critical mass of world-class industry delivering many of Defence’s largest most complex projects , including the $8 billion air warfare destroyers, and sustainment of the Collins submarine fleet and Orion aircraft. South Australia also has a large and varied Defence presence, including key Air Force, Army and Defence Science Technology Organisation elements.

South Australia’s Defence Strategy 2025 Defence SA is working towards South Australia’s Defence Strategy 2025, which proposes outcomes across maritime, land, aerospace, systems and cyber, and science and technology. According to the Hon. Jay Weatherill MP Premier of South Australia, the state is on track to achieve the defence targets, including 37,000 defence sector jobs (direct and indirect) and annual economic contribution of $2.5 billion by 2020. The State Government has a clear direction for the future – driving sustainable Defence industry growth and attracting additional Defence activity to South Australia.

INSIDE THE INDUSTRY: SOUTH AUSTRALIA STATE FOCUS

Many leading Defence companies are headquartered or have significant operations in South Australia, including BAE Systems Australia, Babcock, Lockheed Martin, Mitsubishi Heavy Industries, Navantia, Raytheon Australia, Saab Group, ThyssenKrupp Marine Systems and Ultra Electronics.

The state is also home to the headquarters of ASC, the nation’s largest specialist Defence shipbuilding organisation. ASC built and maintain the Collins Class submarines and is the lead shipbuilder for the Air Warfare Destroyer (AWD) program.

South Australia also has a strong core of specialist Small to Medium Enterprises (SMEs) that service the big players. Together, these companies contribute to a critical mass of world-class industry delivering Defence’s largest projects.

All these companies are supported by the Defence Teaming Centre (DTC), the peak Defence industry body, which is based in South Australia. Founded in 1996 with 24 member companies, the DTC has grown to a membership of over 250 organisations across the nation.

DTC represents and supports Australia’s Defence industry, helping companies operating in the industry to maintain and enhance capabilities, and identify and maximise opportunities in national and global Defence markets.

Over recent years, South Australia has cemented its position as Australia’s Defence State, with achievements such as the successful launch of the first and second Air Warfare Destroyers at Techport Australia.

Construction of the $50 billion Future Submarine program will be undertaken at Techport Australia’s Common User Facility; the largest and most complex Defence project ever undertaken in Australia.

Plus, the first two to four Offshore Patrol Vessels will be built at Techport Australia from 2018, maintaining the skills base and infrastructure for the $35 billion Future Frigate program, which is expected to commence in South Australia from 2020.

South Australia is also a leading national armoured fighting vehicle manufacturing and sustainment hub. BAE Systems Australia, headquartered in South Australia, was the prime contractor responsible for the $1 billion program to extensively modernise Army’s fleet of M113 armoured personnel carriers.

From its national headquarters in Adelaide, General Dynamics Land Systems – Australia (GDLS-A) performed the final assembly and sustainment of the Army’s fleet of Australian Light Armoured Vehicles (ALAV) and has exported large numbers of LAV turrets to overseas markets.

GDLS-A also provides heavy-grade repair and upgrade services for ASLAV in Adelaide and manages the sustainment of Army’s fleets of M1A1 Abrams main battle tanks and M88 Hercules tank recovery vehicles.

It is little wonder that Adelaide is the confirmed location for the headquarters of the new Centre for Defence Industry Capability; the cornerstone of the Government’s strategy for resetting the partnership between Defence and industry.

The new $230 million Centre will be funded by the Department of Defence as part of the 2016 Defence Industry Policy Statement. The funding will be spread across the decade to 2025-2026.

However, according to South Australian Minister for Defence Industries, Martin Hamilton-Smith, “The Naval Shipbuilding Plan lacks detail about how much of the $89 billion naval shipbuilding program will be spent in Australia.”

31

“

We are calling for mandated levels of Australian industry participation to be written into construction contracts for future projects once design activities are complete; in particular the $50 billion Future Submarine program.”

“Our Defence industry has proven that it is capable of competing at an international level. The third ship of the Air Warfare Destroyer program is now meeting international benchmarks with our Collins Class submarines exceeding benchmarks for submarine availability.”

“South Australia’s small and medium enterprises who are working on the Air Warfare Destroyer program are already struggling to survive as work on that program comes to an end.”

“The Australian Government must stand up for our industry and mandate 90% Australian industry participation on the 2018 Offshore Patrol Vessel Program to stabilise the naval shipbuilding supply chain and increase industrial capability,” said Hamilton-Smith.

“The Australian Government’s 2015 RAND report, Australia’s Naval Shipbuilding Enterprise, estimates up to 8.5 million hours of unproductive labour on the Future Frigate program should there not be sufficient industrial capability preserved from the Air Warfare Destroyer program.”

“South Australia stands ready to work with the Australian Government to ensure an efficient build of the required infrastructure at Osborne and ensuring creation of the highly-skilled workforce required for future programs in the state.”

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AUSTRALIAN WELDING | JUNE 2017

Laser Cladding for

Railway Repair In this study, the effects of cladding direction and heat treatment on the microstructure of laser treated rails were investigated. Laser cladding of a premium hypereutectoid rail grade with 410L stainless steel powder was conducted using a fibre laser gun with a powder feeder. Two different cladding directions and different heat treatments were investigated. The application of pre-heating to 350°C on the rail-transversely deposited railhead was insufficient to prevent the formation of martensite at pre-heating length of 400 mm, equal to laser cladding length. As a result, cracking in the clad and heat affected zone (HAZ) was unavoidable. An uncracked non-martensitic microstructure with excellent microstructural consistency across the entire rail-longitudinally deposited railhead and its HAZ was established by a change in cladding direction and using a heat treatment combination consisting of pre-heating, post-heating and slow cooling, although the resulting hardness of the clad layer decreased.

The microstructure of the cladding layer and HAZ were characterised by optical microscopy and SEM. Phase identification and distribution were investigated by using XRD, EDS, and EBSD. Indications of tribological performance of cladding layer in wheel-rail contact were obtained via Vickers indentation and demonstrated great correlation with the microstructure observed.

1. Introduction With the trend of rapidly increasing axle loads and rail traffic, the presence of rolling contact fatigue and wear damages at contact surfaces, particularly in wheels and rails, is problematic in modern railway infrastructure. The degradation leads to the requirement of regular maintenance or even replacement of the components1.

Employment of surface coating techniques, particularly laser cladding technique, appears to be a solution so that extra composite coatings can be applied on either new or used engineering components to gain superior surface properties2-4. Technically, laser cladding is a melting process in which laser beam is used to fuse the desired material addition onto a substrate. A schematic of the typical laser cladding process is shown in Figure 1.

In order to satisfy the demands of today’s rail transportation, laser depositing techniques, consisting of laser glazing and laser cladding, have been employed by some

research groups to modify the surface properties based on the component’s design, whilst the rail steel substrate’s properties are almost unchanged.

Shariff et al5 performed laser glazing treatment on T-12 Indian standard rail with a 10- 15 μm thick graphite layer. Similar work has been conducted by Aldajah6 and fine solidified microstructure was achieved. Niederhauser et al7 studied the fatigue behaviour of B 82 steel cladded with Co-Cr alloys. This steel is widely used for railway wheels in Sweden. The results presented a consistent and favourable fatigue behaviour of the cladded specimens.

Ringsberg et al8 investigated the rolling contact fatigue resistance of the pearlitic UIC 900A (R260) steel cladded with a Co-Cr alloy using finite element numerical simulation.

Franklin et al9 worked on laboratory tests also regarding rolling contact fatigue and wear behaviour of the laser cladded UIC 900A (R260) specimens.

Ultimately, Hiensch et al10 conducted actual field tests regarding rolling

Fig. 1. Schematic of a typical laser cladding unit with a coaxial laser head.

contact fatigue and squeal noise behaviour of laser-cladded prototype UIC 900A (260-grade) rails. The work

by Franklin et al and Hiensch et al was done under the same European project. However, information on the optimum processing conditions to be used during the cladding deposition on rail steels is sparse.

The present work aims to examine the influence of laser cladding directions and, pre-heat and post heat treatments on microstructural characteristics and tribological properties of a functionally graded rail. The 410L stainless steel was selected as the clad material owing

INSIDE THE INDUSTRY: LASER CLADDING FOR RAILWAY REPAIR

33

By Quan Lai, Ralph Abrahams, and Wenyi Yan from the Department of Mechanical and Aerospace Engineering at Monash University; Cong Qiu and Peter Mutton from the Institute of Railway Technology at Monash University; Anna Paradowska from ANSTO; and Mehdi Soodi from Hardchome Engineering.

to its high strength, excellent resistance to abrasion and corrosion, and great laser compatibility11-13.

Consequentially, laser cladding of 410L stainless steel was performed on a premium hypereutectoid rail grade using a 4 kW IPG fibre laser.

The microstructural evolutions of the 410L depositing layer and the heat affected zone (HAZ) of the rail substrate were analysed via optical microscopy (OM) and Scanning Electron Microscopy (SEM). Electron dispersive X-ray spectroscopy (EDS) was also utilised for compositional analyses at the clad and the cladsubstrate interface. Phases of the 410L clad were analysed using X-ray diffractometer (XRD) and Electron Backscattered Diffraction (EBSD).

Indications of wear resistance of cladding layer were obtained via Vickers indentation, thereby, the correlation between the microstructural characteristics and the wear performance was also established.

2. Experimental Procedure 2.1. Materials A premium hypereutectoid rail

grade of Nippon Steel Corporation (NSC), often used in high axle load applications with high traffic, was selected as the model substrate.

The composition complies with the EN 13674 requirements for R400HT grade. The actual composition and R400HT specifications are provided in Table 1a. The 410L grade stainless steel powder with 150 Îźm average particle diameter was centrally cladded on the rail head. Figure 2 shows the schematic of a typical laser cladded rail section with a defined coordinate system. The chemical composition of the 410L powder is listed in Table.1b and the morphology of its powder is depicted in Figure 3. Prior to applying the laser treatment, the rail portions were ground, polished and cleaned.

2.2 Laser Cladding Process Parameters The laser cladding process was carried out by concurrently melting the addition and substrate materials using a laser coaxial head comprising of 4 kW IPG fibre laser gun and a Sultzer-Metco twin-10 powder feeder. This laser head was manipulated by a Motoman XRC SK

16X 6-axis CNC unit. The laser beam was optically modified to deliver a concentrated circular laser spot with a spot size of 5 mm on the surface of the substrate. Shielding gas of 50% Argon and 50% Helium around the laser beam was used to avoid undue oxidation during the process. The system was air-cooled.

Three groups of specimens were produced by altering the heat treatment procedure and cladding direction as shown in Table 2. Laser power, scanning speed, and powder feed rate were remained constant at 3.2 kW, 1000 mm/s and 26.4 g/min, respectively.

Figure 4 shows the sectioning locations used to obtain metallographic specimens of the three specimen groups. The resulting metallurgical specimens were further sectioned in the transverse direction (Y), then mounted, ground, polished and analysed repeatedly until acquiring decent microstructural representatives of each of the three groups. Twostage etching procedure was applied. A 2% Nital etching solution was used to visualise rail steel

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AUSTRALIAN WELDING | JUNE 2017

Fig. 3. Electron micrographs of the 410L grade stainless steel powder at (a) low magnification, and (b) high magnification.

Fig. 2. Schematic of the laser cladded rail sample with detailed dimensions.

Elements in weight percent (wt. %) Identification

C

Si

Mn

P

S

Cr

Ni

Mo

V

Nb

Al

Rail Material

0.93

0.28

0.95

0.018

0.014

0.20

<0.01

<0.01

<0.01

<0.01

<0.005

RH400HT (*)

0.881.07

0.180.62

0.951.35

0.025 (max)

0.025 (max)

â&#x2030;¤0.30

N.S

N.S

0.03 (max)

N.S

0.004

(*) European Committee for Standardisation (CEN), EN13674-1:2011 Railway Applications-Track-Rail-Part 1: Vignole railway rails 46kg/m and above.

Table 1a. Chemical compositions of the substrate material (N.S = Not significant).

Elements in weight percent (wt. %) C

Mn

Si

P

S

Cr

Nb

Ni

Al

Fe

Mo

Cu

Ti

V

0.01

0.51

0.47

0.01

0.01

12.7

0.02

0.08

0.01

Bal

0.01

0.05

<0.01

0.01

Table 1b. Chemical compositions of the hard-facing material.

substrate microstructure. A Kallingâ&#x20AC;&#x2122;s no. 2 (5g CuCl2, 100 ml HCl and 100ml ethanol) was used to reveal microstructure of the clad. The metallographic specimens were then analysed using Nikon Eclipse optical microscope and JEOL 7001F FEG scanning electron microscope (SEM). The Oxford X-max 80 Silicon Drift type electron dispersive X-ray spectroscopy (EDS) detector attached to the 7001F SEM was also utilised for compositional analysis.

Phase and crystallographic studies were performed by the Bruker D8 Advance ECO X-ray diffractometer (XRD) with Co K radiation operating at 40kV and 25mA, and HKL Nordlys S electron backscattered diffraction (EBSD) camera operating in conjunction with Oxford Instruments Aztec software system.

Microhardness measurements were achieved using the Struers A300 Duramin hardness tester.

3. Discussion At similar cladding process parameters, using different cladding directions and heat treatment regimes, during the laser deposition, on the railheads generated variation in the microstructure of the clads and HAZ. 3.1. Microstructure of the Clads 3.1.1. The rail transversely deposited clad with pre-heating only (Group 1) Previous works15, 16 reported the influence of local G/R ratio, where G is temperature gradient and R is solid-liquid interface growth rate, on solidification modes over the thickness of cladding layers. In this current work, the fine dendritic structure, in the rail-transversely deposited clad (Group 1), was formed by the rapid heat transfer facilitated by the substrate acting as an effective heat sink during the cladding process. This also causes variation in G and R across the thickness of the clad. Planar dendrites developed in highly

localised regions with significant G/R ratio near the interface, since the local temperature gradient (G), was virtually infinite. The ratio significantly was reduced as approaching the middle section of the clad, which resulted in the gradual formation of cellular and columnar dendrites. Likewise, the G/R ratio was approximately lowest in the vicinity of the top surface giving mostly equiaxed dendritic grain. Consequentially, from the top to the bottom of the clad, the three typical grain morphologies of the dendritic structure in Group 1 clad were equiaxed grains, cellular grains, columnar grains and planar crystals as observed in Figure 9.15 The X-ray diffraction patterns of the laser treated 410L stainless steels were demonstrated to contain alpha (a) and gamma (y) irons.

The martensite (a) and retained austenite (y) were reported to locate in dendrites and dendritic grain boundaries, respectively12, 17.

Similarly, the XRD and EBSD results

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INSIDE THE INDUSTRY: LASER CLADDING FOR RAILWAY REPAIR

Fig. 4. Sectioning locations used for metallographic specimens displayed with their corresponding order.

Specimens

Fig. 5. X-ray diffraction patterns.

Heat treatment procedure

Cladding direction

Group 1

Pre-heating to 350°C (HTA)

Tranverse

Group 2

Pre-heating to 350°C (HTA)

Longitudinal

Group 3

Pre-heating to 350°C (HTA) Post-heating to 350°C and then slow-cooled to room temperature

Longitudinal

Table 2. Parameter sets applied for comparative study of cladding direction and heat treatment.

in the current investigation, as evident in Figure 5 and Figures 6a and 6b, show the presence of martensite with BCC within the dendrites and retained austenite with FCC between the dendrites (or at dendritic grain boundaries) and at the interface.

According to Krakhmalev et al12, segregation of Carbon (C) promoted growth of the retained austenite phase. However, in the current work micro-segregation of Chromium (Cr) and Manganese (Mn) to the dendritic grain boundaries was also noted in the specimens of Group 1.

During the rapid solidification, the distributions of Chromium (Cr) and Manganese (Mn) alloying elements were greatly influenced by large cooling rate, as evident in Figure 6(c) and (d) respectively. In other words, the Cr and Mn elements showed high tendency to segregate to the last areas to solidify, which are the locations between the dendritic arms/ at grain boundaries in this case 18.

The amount of retained austenite in the steel was greatly influenced by the alloying elements19. The Mn and Cr segregated to the dendritic grain boundaries as shown in Figure 6(a3, a4) and (b3, b4). The combined effects of alloying elements led to the formation of retained austenite at the dendritic grain boundaries in the Group 1 specimens.

The other elements were distributed homogeneously throughout the clad.

The retained austenite at the interface is probably coming from a origian that is different to the one discussed above and could be attributed to the substrate dilution, so that the carbon (C), acting as an austenitic stabiliser, of the 0.84– 0.95 wt.% C rail substrate melted participates in the constitution of the 0.01 wt.% C clad.

Solidification cracks were detected in the transversely deposited clad (Group 1) as shown in Figure 18, which have been reported to be caused by rapid cooling rate, which induced substantial residual stress in the clad20.

3.1.2 The rail-longitudinally deposited clad with pre-heating only (Group 2) As subjected to a modification in cladding direction, there are corresponding changes in morphology and microstructural characteristics of the raillongitudinally deposited clad (Group 2). Phases, such as retained austenite, ferrite and martensite were identified by the outcomes of the XRD and EBSD analyses.

Small occasional retained austenite colonies near the 410L - rail interface and bands of elongated ferritic colonies, located near the top surface and in the laser overlapping regions as evident in Figures 5 and 7. Both the bands and the

matrix possess BCC, whereas the small retain austenite colonies in the vicinity of the interface with FCC owing to the aforementioned substrate dilution.

The employment of rail-longitudinal cladding direction in Group 2 specimens removed the prevalent dendritic characteristics in the clad’s microstructure of the regular laser treated specimens reported by previous studies15, 21-23, or the Group 1 specimens in particular.

This may be attributed to a decrease in the total accumulated heat used to penetrate the substrate, correspondingly lowering the total amount of dilution and the thermal gradient during the clad solidification. The longer length of each laser run will result in less heat accumulated for subsequent runs owing to heat conduction via substrate and air convection.

Furthermore, the repeated occurrence of martensite in the vicinity of the interface, and ferrite colonies near the top surface might incadicate the variation in dilution level, particularly carbon with high diffusivity in steel24, 25. The further away from interface, the lower dilution level will be. The greater dilution level near the interface might facilitate the phase transformation of martensite. In contrast, ferrite

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Fig. 6a. Typical EBSD acquired results of the 410L rail-transversely deposited clad (Group 1) in the clad (a) and at the interface (b) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distributions.

Fig. 6b. Typical EBSD acquired results of the 410L rail-transversely deposited clad (Group 1) at the interface (b) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distributions.

Fig. 7a. Typical EBSD acquired results of the 410L rail-longitudinal deposited clad (Group 2) in the clad (a) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distributions.

colonies, densely occupy the nearby top surface where the dilution level might be lower. Also, Ferrite was found to nucleate from the interface between two separate laser runs.

This can be caused by the insufficient concentration of local alloying elements to dilute to the new clad.

Each of these sub-regions is completely influenced by their local thermal history. All sub-regions were discerned in the three clads as evident in Figures 12-17.

resulting phases might be pearlite, bainite, martensite or tempered martensite. For rail-transverse sections, coarse-grained HAZ characterised by full pearlite at the middle section shown in Figure 12(c) and Figure 13(b), and martensite at the gauge corners shown in Figure 12 (a) and (c).

3.1.3. The rail-longitudinally deposited clad with pre-heating, post-heating and slow cooling (Group 3) The rail-longitudinal cladding direction applied in the Group 3 specimens induced the cladâ&#x20AC;&#x2122;s microstructural characteristics, which is relatively analogous to those of the Group 2 clad. Retained austenite, ferrite and martensite were still recognised by the results of the XRD and EBSD analyses. However, the application of PWHT and slow cooling has tempered the martensite formed and facilitated the increases in grain size and volume fraction of ferrite as discussed in Section 3.2.

3.2. Microstructure of the HAZs Beneath the 410L Clad Under the 410L clads, multiple sub-regions in the HAZs were developed as a result of the substrate microstructure subjected to the effects of heating and cooling during the laser cladding process.

For hypereutectoid rail steel, four main sub-regions are pronouncedly identifiable from the interface to the unaffected substrate, (i) Partially molten zone, (ii) Coarse-grained HAZ, (iii) Fine-grained HAZ, and (iv) Inter-critical HAZ respectively.

3.2.1. The rail transversely deposited clad with pre-heating only (Group 1) For the rail-transversely deposited clad (Group 1), in the spheroidised or partial spheroidised zone shown in Figure 13(c) and (d), the local peak temperature is always below the critical temperature when austenite begins to form, which implies that the majority of the heat supplied in this zone is to temper the pearlitic microstructure of the substrate26, 27.

Fine-grained HAZ with the fully pearlitic morphology within fine nodules in the region located directly above the transition region, as shown in Figure 13(c). The local peak temperature was determined to be greater than the critical temperature Ac3, which is the temperature at which austenitic transformation was completed. However, the rapid cooling rate induced a fine grain structure within the sub-region.

Adjoining to the interface, thereby, the coarse-grained HAZ is subjected to the high peak temperature beyond (Ac3). The higher temperature facilitates the significant grain growth. During the cooling stage, depending on the cooling rate, the austenitic grains undergo different solid state transformations. The

Similarly, in the rail longitudinal sections, the larger extent of the martensitic was detected at all sections near the interface, especially where the starting and ending of the laser tracks are, shown in Figure 12(d). It is attributed to the pre-heating temperature applied was not sufficient to prevent the martensitic transformation. In other words, the resulting temperature of the pre-heated substrate was under the martensitic transformation temperature, which led to a similar effect to quenching. Therefore, the larger surrounding surface area, the larger extent of martensite formed.

As the process proceeding, the heat was accumulated above the martensitic transformation temperature and induced the pearlitic coarse-grained HAZ at the middle section of the laser cladding pad, as shown in Figure 12 (b).

Nevertheless, the accumulated heat was dissipated more rapidly at the gauge corners due to the large neighbouring surface area of the substrate, thus, the martensite was formed. At the starting and ending of the laser tracks, the neighbouring substrateâ&#x20AC;&#x2122;s surface area was even

INSIDE THE INDUSTRY: LASER CLADDING FOR RAILWAY REPAIR

Fig. 7b. Typical EBSD acquired results of the 410L rail-longitudinal deposited clad (Group 2) at the interface (b) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distributions.

Fig. 9. Micrographs showing the fine dendritic microstructure of the cross sections of the 410L rail-transversely deposited clad (Group 1) at (a) left gauge corner (Start), (b) middle section and (c) right gauge corner. (d) Typical equiaxted dendritic grains, (e) columnar/cellular dendritic grans. (f) planar dendritic grains located from top to bottom of the Group 1 clad, respectively.

Fig. 8a. Typical EBSD acquired results of the 410L rail-longitudinal deposited clad (Group 3) in the clad (a) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distributions.

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Fig. 8b. Typical EBSD acquired results of the 410L rail-longitudinal deposited clad (Group 3) at the interface (b) with (1) the band contrast (BC) image for topographical information, (2) the image of phase distribution, and the EDS images of (3) Cr and (4) Mn element distions.

Fig. 10. Micrographs showing the 410L rail-longitudinally deposited clad (Group 2) microstructure of the cross sections of the at (a) left gauge corner, (b) middle section and (c) right gauge corner. (d) Ferritic colonies in the (e) martensite matrix. (f) The Group 2 interface (F=Ferrite, M=Martensite).

Fig. 12. Micrograph showing the HAZ and rail substrate of the railcross sections at (a) left gauge corner, (b) right gauge corner, (c) middle section and (d) a representative of the longitudinal sections under the 410L rail-transversely deposited clad (Group 1). The light etching microconstituent in the HAZ of (a), (b) and (d) is martensite.

Fig. 11. Micrograph showing the 410L rail-longitudinally deposited clad (Group 3) microstructure of the cross sections of the at (a) left gauge corner (STart), (b) middle section and (c) right gauge corner. (d) Ferritic colonies in the (e) tempered martensite matrix. (f) Small retained austenite colonies developed near the interface, due to dilution.

(F=Ferrite, TM=Tempered martensite, RA=Retained austenite).

Fig. 14. Micrograph showing the HAZ and rail substrate of the railcross sections at (a) left gauge corner, (b) right gauge corner, (c) middle section and (d) a representative of the longitudinal sections under the 410L rail-transversely deposited clad (Group 2). The light etching microconstituent in the HAZ of (b) and (d) is martensite.

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Fig. 13. SEM micrographs of the sub-regions in the Group 1 HAZ. (a) Partially molten zone featuring a metallurgical bond at the top. In the middle, (b) Coarse-grained HAZ characterised by fully pearlitic structure and (c) Fine-grained HAZ characterised by partially and fully pearlitic structure, and (d) Inter-critical HAZ characterised by spheroidite at the interface under the 410L rail-transversely deposited clad (Group 1).

Fig. 15. SEM micrographs of the sub-regions in the Group 2 HAZ. (a) Partially molten zone featuring a metallurgical bond at the top. In the middle, (b) coarse-grained HAZ characterised by fully bainitic structure and (c) fine-grained HAZ characterised by a combination of pearlite and bainite, and (d) Inter-critical HAZ characterised by spheroidite at the interface under the 410L rail-transversely deposited clad (Group 2).

Fig. 17. SEM micrographs of the sub-regions in the Group 3 HAZ. (a) Partially molten zone featuring a metallurgical bond at the top. In the middle, (b) Coarse-grained HAZ characterised by fully pearlitic structure and (c) Fine-grained HAZ characterised by partially and fully pearlitic structure, and (d) Inter-critical HAZ characterised by spheroidite at the interface under the 410L rail-longitudinally deposited clad (Group 3).

larger, correspondingly lager extent of martensite was found.

SEM, and was seen to consist of bainite as show in Figure 15(b). For longitudinal sections, the resulted HAZ’s microstructure is martensite, which agrees with that of the Group 1 specimens and suggests that the pre-heating temperature of 350°C at the length equal to the cladding length is insufficient to hinder the formation of martensite in the HAZ. The Fine-grained HAZ with pearlite inside fine nodules is shown in Figure 15(c) at all rail transverse and longitudinal sections. Similar to the Group 1 specimens, the spheroidised pearlite was present next to the unaffected base rail, as its local peak temperature was only to temper the microstructure.

The involvement of PWHT in the Group 3 heat treatment regime is to mitigate the residual stresses, as a hardness control method and enhance material strength for the deposited layers; and eliminate martensitic formation in the HAZ or, at least, reduce the cracking tendency of the martensite formed in the HAZ by its tempering effects.

Tempered martensite was observed instead, particularly at the starting and ending of the laser tracks. This implies PWHT has limited effect to avoid martensite formation in the HAZ, but it was able to lower cracking tendency in the HAZ, as there were not many pronounced cracks detected.

3.2.3. The rail-longitudinally deposited clad with pre-heating, post-heating and slow cooling (Group 3) For the rail-longitudinally deposited clad (Group 3), the four sub-regions were also discerned. Under the influence of the Group 3 heat treatment regime, the microstructural features in the HAZ are relatively analogous to those of the Group 2. At almost all rail transverse and longitudinal sections, the solid phase in the coarse-grained HAZ was transformed to bainitic morphology as shown in Figure 17(b), the Fine-grained HAZ with pearlite inside fine nodules is shown in Figure 17(c), and spheroidised pearlite as shown in Figure 17(d).

4.3. Microhardness Distributions

Partially molten zone was at the exact interface of the Group 1 clad and rail substrate, shown in Figure 13(a). It implies that a metallurgical bond has been established, which possesses better sustainability for high impact loads, heavy loaded and stresses situations comparing to mechanical bond.

3.2.2. The rail-longitudinally deposited clad with pre-heating only (Group 2) Heat affected zones which are generated by laser cladding in the parent material of the Group 2 specimens are also composed of the aforementioned four sub-regions.

In the coarse-grained HAZ, for the rail transverse sections, the preheating temperature applied was capable of avoiding the martensitic transformation at the left gauge corner sections where the starting laser runs are and also the middle section as shown respectively in Figure 14(a) & (c), but not at the right gauge corner where the ending laser runs are as shown in Figure 14(b). This phenomenon is related to the heat dissipation of the applied pre-heating temperature, as the laser source is travelling from the left gauge corner to the right gauge corner. The microstructural features of the left gauge corner and middle sections were more clearly revealed by the means of

4.3.1. The rail transversely deposited clad with pre-heating only (Group 1) The inverse correlation between hardness and wear rate was well established in the literature, which is the higher the hardness, the lower the wear rate28-30. Therefore, indications of the laser clads’ tribological performance in wheel-rail contact can be obtained by means of Vickers indentation. Krishna et al11 has reported that the highest average hardness of the laser surface melted AISI 410 stainless steel sheets is 350 HV. However, in the current study the highest average hardness of 720 HV was corresponded for the

INSIDE THE INDUSTRY: LASER CLADDING FOR RAILWAY REPAIR

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Fig. 22. Morphology of solidification cracks in the cladding layer of Group 1.

Fig. 16. Micrograph showing the HAZ and rail substrate of the rail-cross sections at (a) left gauge corner, (b) right gauge corner, (c) middle section and (d) a representative of the longitudinal sections under the 410L rail-transversely deposited clad (Group 3). Tempered martensite was found occasionally.

rail-transversely deposited clad (Group 1), which is corresponding to the aforementioned martensitic dendrites. It implies that the only application of pre-heating to 350°C at the heating length of 400 mm in Group 1 specimens was insufficient to lessen the rapid cooling rate conditioned by the substrate, and prevent the formation of martensite.

Lewis et al.31, 32 has reported that martensitic stainless steels with average hardness of approximately 650 HV showed superior wear and rolling contact fatigue (RCF) resistance compared to the R260 reference rail.

However, martensitic microstructure of the clad is known for greater brittleness and cracking tendency compared to other microconstituents for a given C content. The average hardness at gauge corners of both the clad and HAZ was greater than that of the middle section, which may be attributed to the accumulation of heat at the middle tracks. The Group 1 HAZ’s average hardness of approximately 400 HV is comparable to the value of the unaffected base material. The local hardness variation in the HAZ is significant, particularly at gauge corners, owing to the proximity of martensite and spheroidite in the HAZ with approximately 700 HV and 300 HV, respectively.

4.3.2. The rail longitudinally deposited clad with pre-heating only (Group 2) Along with the pre-heating temperature of 350°C at the heating length of 400m, the utilisation of the rail-longitudinal cladding direction

has lowered the clad’s average hardness values approximately to the average hardness of the laser surface melted AISI 410 stainless steel sheets of 350 HV11.

There were no significant changes in the trends from the left gauge corner to the right gauge corner.

The hardness was found to be the lowest in the vicinity of the clad’s top surface owing to the presence of ferrite, and steadily increasing as martensite was predominant towards the clad-substrate interface. With the above pre-heating conditions, the change in the cladding direction was incapable of removing martensite, or reducing significantly the peak hardness values in the HAZ. Indeed, the peak average hardness values recorded in the HAZ and associated with martensite were 635 HV at the right gauge corner where the last laser tracks are. This further consolidates the aforementioned discussion of the infeasibility in applying the pre-heating temperature of 350°C at the heating length equal to cladding length in avoiding martensitic formation in the HAZ. 4.3.3. The rail longitudinally deposited clad with pre-heating, post-heating and slow cooling (Group 3) On the other hand, for raillongitudinally deposited clad (Group 3), the addition of postheating to 350°C and slow cooling accompanied by the change in cladding direction over-tempered the clad’s microstructure. Accordingly, the clad’s average hardness was decreased substantially.

Comparing to the substrate’s average hardness of 400 HV, the lowest clad’s hardness of 251 HV was considered to be soft, which might cause detrimental effects towards the wear resistant characteristics of the cladded rail. The relatively homogeneous microstructure with mostly bainite in the Group 3 HAZ produced hardness values ranging from 370 - 550 HV across the entire railhead, which is adequate for the railwheel applications in term of wear resistance. No crack was detected in the Group 3 HAZ. The clad’s average hardness decreases to 340.11 HV, 347.57 HV and 250.57 HV for the middle section, left gauge corner, and right gauge corner respectively as shown in Figure 18(c).

It was noted that the variation in hardness between the gauge corners was significant. The reason being is that the laser tracks were cladded from right corner to left corner, thus the local temperature of the left gauge corner is more likely to lower than that of the right as the rail preheating temperature is cooling down over time. Based on the results from this study, it is suggested to shorten the cladding length or/and use solid-solution strengthening, such as Lanthanum oxide, to increase the hardness of the 410L material.

Investigation by Hang et al33 established the existence of remelted regions in multiple overlapping cladtracks. In agreement with that, the horizontal microhardness distribution of the three clads in the current investigation indicates hardness

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Fig. 18. Vertical hardness distribution of the rail transversely deposited (Group 1) clad.

Fig. 19. Vertical hardness distribution of the rail transversely deposited (Group 2) clad.

Fig. 20. Vertical hardness distribution of the rail transversely deposited (Group 3) clad.

values varied in a sinusoidal fashion with horizontal distance across the clads, as evident in Figure 19(a)-(c).

due to the corresponding smaller amount of ferrite in the remelted regions, as evident in Figures 7 and 10. Lastly, the sinusoidal variation in hardness distribution of the Group 1 clad was the least pronounced as fine dendritic martensite was predominant in its resulted clad microstructure. The observed microstructural characteristics of the remelted regions for the three clads were well correlated with their hardness variations. The hardness variation in Group 3 is not favourable for rail/wheel contact, since softened zones on the rail surface are prone to corrugation and may trigger deep rolling contact fatigue (RCF) cracks.

performance of the laser-cladded rail steels in wheel-rail contact are summarised as follows.

The troughs of the hardness profiles fell into the remelted regions of the clads, where the microstructure is likely tempered or even recrystallised by the heat of the later tracks and the heat treatments applied. In the case of the rail longitudinally deposited clad (Group 3), the aforementioned clad microstructure at the remelted regions consists of the largest extent of ferrite amongst the three clads.

This ferritic microstructure is known to be associated with low hardness, which results in the pronounced troughs in the hardness profile of the Group 3 clad.

Also, the sinusoidal hardness variation was found in the horizontal hardness profile of the Group 2 clad, but to a lesser extent in amplitude,

5. Conclusions The conclusions made from the investigation of the influence of altering cladding directions and heat treatments applied on the potential

For HAZ, the application of preheating to 350°C at the heating length equal to the cladding length was concluded to be insufficient to prevent the formation of martensite for both cladding directions, the rail-transverse (Group 1) and raillongitudinal directions (Group 2). As a result, cracking in the HAZ would be likely unavoidable.

Nevertheless, the combination of pre-heating, post-heating and slow cooling was proven to provide beneficial tempering to the HAZ microstructure, particularly in those with martensite, and excellent microstructural consistency across the entire rail-longitudinally deposited railhead (Group 3).

For the 410L clads, cladding direction has a significant impact on the microstructural characteristics of the deposited clads. Fine dendritic martensite with cracks in the Group 1 was replaced with the resulted microstructure consisting of martensite matrix and occasional ferritic colonies in the Group 2 by being subjected only to a change in cladding direction. This is attributed to the combination effects of cooling rate and dilution conditioned by the substrate. Employment of postheating and slow cooling leads to a detrimental softening effect on the 410L rail-longitudinally deposited clad (Group 3) with relatively low hardness. it is recommended to shorten the cladding length or/and use solidsolution strengthening to increase the hardness of the 410L material.

Distribution of the microconstituents

INSIDE THE INDUSTRY: LASER CLADDING FOR RAILWAY REPAIR

Fig. 21a. Horizontal hardness distribution of (a) the rail transversely deposited clad (Group 1).

Fig. 21b. Horizontal hardness distribution of the rail longitudinally deposited clad at railtransverse middle sections (Group 2).

in the clads, particularly retained austenite and ferrite, was strongly influenced by the micro-segregation of alloying elements within the clads during solidification and at the interface owing to dilution from the parent material. Microstructural characteristics of the clad’s remelted regions was dependent on the cladding directions and heat treatments; and showed a similar correlation with hardness distribution.

[8] J.W. Ringsberg, A. Skyttebol, B.L. Josefson.

Investigation of the rolling contact fatigue resistance of laser cladded twin-disc specimens: FE simulation of laser cladding, grinding and a twin-disc test. International Journal of Fatigue 2005;27(6):702-714.

[9] F. Franklin, G.-J. Weeda, A. Kapoor, E. Hiensch.

Rolling contact fatigue and wear behaviour of the Infrastar two-material rail. Wear 2005;258(7):10481054.

[10] M. Hiensch, P.-O. Larsson, O. Nilsson, D. Levy, A. Kapoor, F. Franklin, J. Nielsen, J.W. Ringsberg, B.L. Josefson. Two-material rail development: field test results regarding rolling contact fatigue and squeal noise behaviour. Wear 2005;258(7):964-972.

[11] B.V. Krishna, A. Bandyopadhyay. Surface modification of AISI 410 stainless steel using laser engineered net shaping (LENS TM). Materials & Design 2009;30(5):1490-1496.

[12] P. Krakhmalev, I. Yadroitsava, G. Fredriksson, I. Yadroitsev. In situ heat treatment in selective laser melted martensitic AISI 420 stainless steels.

Materials & Design 2015;87:380-385.

[13] Y. Zhang, G. Yu, X. He, W. Ning, C. Zheng.

Numerical and experimental investigation of multilayer SS410 thin wall built by laser direct metal deposition. Journal of Materials Processing Technology 2012;212(1):106-112.

[14] M. Salehi, K. Dehghani. Structure and properties of nanostructured aluminum A413. 1 produced by melt spinning compared with ingot microstructure. Journal of Alloys and Compounds 2008;457(1):357-361.

[15] I. Hemmati, V. Ocelik, J.T.M. De Hosson.

Microstructural characterisation of AISI 431 martensitic stainless steel laser-deposited coatings. Journal of materials science 2011;46(10):3405-3414.

[16] S. Kou 2nd, Welding metallurgy 2nd edn, John Wiley & Sons, New Jersey, 2003.

[17] R. Colaço, R. Vilar. Stabilisation of retained austenite in laser surface melted tool steels. Materials Science and Engineering: A 2004;385(1):123-127.

[18] M. Gagné. The Sorelmetal book of ductile iron.

Rio Tinto Iron & Titanium Inc 2004:23-45.

[19] G.E. Totten, M.A. Howes. Steel heat treatment handbook. CRC Press; 1997.

[20] C. Lee, H. Park, J. Yoo, C. Lee, W. Woo, S. Park. Residual stress and crack initiation in laser clad composite layer with Co-based alloy and WC+ NiCr. Applied Surface Science 2015;345:286-294.

[21] Z. Zhang, P. Farahmand, R. Kovacevic. Laser cladding of 420 stainless steel with molybdenum on mild steel A36 by a high power direct diode laser. Materials & Design 2016;109:686-699.

[22] K. Li, D. Li, D. Liu, G. Pei, L. Sun. Microstructure evolution and mechanical properties of multiple-layer laser cladding coating of 308L stainless steel. Applied Surface Science 2015;340:143- 150.

[23] R.A. Jeshvaghani, M. Shamanian, M.

The presented findings established the influence of laser depositing directions and heat treatments on the resultant microstructure of the 410L clad and the HAZ of the rail substrate, and also the average hardness distribution across the clads, which are the key indications of wear performance of the cladded rail in wheel-rail contact.

References [1] D. Cannon, K.O. Edel, S. Grassie, K. Sawley. Rail defects: an overview. Fatigue & Fracture of Engineering Materials & Structures 2003;26(10):865-886.

[2] J.C. Betts. The direct laser deposition of AISI316 stainless steel and Cr 3 C 2 powder.

Journal of Materials Processing Technology 2009;209(11):5229-5238.

[3] W. Li, L. Yan, S. Karnati, F. Liou, J. Newkirk, K.M.B. Taminger, W.J. Seufzer. Ti-Fe Intermetallics Analysis and Control in Joining Titanium Alloy and Stainless Steel by Laser Metal Deposition. Journal of Materials Processing Technology 2016.

[4] T. Abioye, J. Folkes, A. Clare. A parametric study of Inconel 625 wire laser deposition.

Journal of Materials Processing Technology 2013;213(12):2145-2151.

[5] S. Shariff, T. Pal, G. Padmanabham, S. Joshi. Sliding wear behaviour of laser surface modified pearlitic rail steel. Surface Engineering 2010;26(3):199-208.

[6] S. Aldajah, O.O. Ajayi, G.R. Fenske, S. Kumar.

Investigation of top of rail lubrication and laser glazing for improved railroad energy efficiency.

Journal of Tribology 2003;125(3):643-648.

[7] S. Niederhauser, B. Karlsson. Fatigue behaviour of Co–Cr laser cladded steel plates for railway applications. Wear 2005;258(7):1156-1164.

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Fig. 21c. Horizontal hardness distribution of the rail longitudinally deposited clad at railtransverse middle sections (Group 3).

Jaberzadeh. Enhancement of wear resistance of ductile iron surface alloyed by stellite 6. Materials & Design 2011;32(4):2028-2033.

[24] G.G. Tibbetts. Diffusivity of carbon in iron and steels at high temperatures. Journal of Applied Physics 1980;51(9):4813-4816.

[25] W.F. Gale, T.C. Totemeier. Smithells metals reference book. Butterworth-Heinemann; 2003.

[26] H. Bhadeshia, R. Honeycombe. Steels: microstructure and properties: microstructure and properties. Butterworth-Heinemann; 2011.

[27] H. Kerr. A review of factors affecting toughness in welded steels. International Journal of Pressure Vessels and Piping 1976;4(2):119-141.

[28] S. Lewis, R. Lewis, D. Fletcher. Assessment of laser cladding as an option for repairing/enhancing rails. Wear 2015;330:581-591.

[29] S. Lewis, S. Fretwell-Smith, P. Goodwin, L. Smith, R. Lewis, M. Aslam, D. Fletcher, K. Murray, R. Lambert. Improving Rail Wear and RCF Performance using Laser Cladding. Wear 2016.

[30] Y. Jin, M. Ishida, A. Namura. Experimental simulation and prediction of wear of wheel flange and rail gauge corner. Wear 2011;271(1):259-267.

[31] W.D. Callister, D.G. Rethwisch. Materials science and engineering: an introduction. Wiley New York; 2007.

[32] G. Lacroix, T. Pardoen, P. Jacques. The fracture toughness of TRIP-assisted multiphase steels. Acta Materialia 2008;56(15):3900-3913.

[33] S.-H. Wang, J.-Y. Chen, L. Xue. A study of the abrasive wear behaviour of laser-clad tool steel coatings. Surface and Coatings Technology 2006;200(11):3446-3458.

Acknowledgments This work was supported by Hardchrome Engineering, the Welding Technology Institute of Australia (WTIA), ARC linkage project (LP140100810), the Monash Centre for Electron Microscopy (MCEM), the Australian Nuclear Science and Technology Organisation (ANSTO), the Institute of Railway Technology (IRT), and Monash X-ray Platform (MXP). The authors also wish to acknowledge the assistance of Mr Andrew Dugan, General Manager of Hardchrome Engineering, Mechanical Engineering Workshop at Monash University, and Mr Yuxuang Wu.

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Q&A with the First Welder

Registered on the AWCR Earlier this year, Louis Duchesne, a boilermaker working on the WestConnex project in Sydney, became the first welder certified under the Australian Welder Certification Register (AWCR). According to Louis, the certification process was simple and straightforward, and offers a whole range of benefits to Australian welders. In this Q&A, Louis’ describes his career in the welding industry, including working on several iconic projects, including the Sydney Opera House.

In late 2016, WestConnex (the New South Wales Government body responsible for upgrading and building new motorways in Sydney) collaborated with the WTIA to develop welding procedures for the repair of Tunnel Boring Machines (TBMs). These TBMs are being used as part of construction activities on both the M4 East and the New M5 projects.

A three day training package was developed at the end of 2016 and delivered by NSW TAFE trainers in January and February 2017 at Lincoln Electric Company in Padstow.

The training qualified existing and future WestConnex welders on the welding techniques required for maintenance activities on the TBMs. Significantly, the training resulted in the welders being the first to be registered on the WTIA’s newly-launched Australian Welder Certification Register (AWCR).

Louis Duchesne, a boilermaker working on the WestConnex project, was the very first welder certified under the AWCR. Louis is currently working on the WestConnex M4 East project, carrying out tasks such as repairing cutter heads, hardfacing in the tunnel, and fabrication in the workshop.

general, it would be very beneficial to undertake the training developed by the WTIA and delivered by NSW TAFE. For anyone that hasn’t worked on a tunnelling project before, the course would be really helpful—it would help them know what to expect when they arrive on-site.”

“I think it’s great that welders and boilermakers now have the opportunity to be certified by an independent third party. Rather than having to explain what you’ve done, and what qualifications you have, you can just ask your employer, or a prospective new employer, to take a look at the WTIA’s website. It makes it the process much easier for welders,” said Louis.

The AWCR provides a national framework for qualifying and testing welders to International Standard ISO9606-1. The AWCR allows qualified and certified Registered Welders (RW) to be able to work on any site without further testing, resulting in a significant cost saving to industry. Industry is able to assess welders against current, rather than past, performance.

According to Louis, “The process of getting certified under the Australian Welder Certification Register was very straightforward.”

It also provides industry with access to a database of welders with up to date certifications, minimises risk of welders failing a weld procedure through adherence to a certified competency level, and generates data for skills gap analysis to enable development of training to upskill the workforce.

“For anyone working as boilermaker, or working in the welding industry in

For more information, visit: www.awcr.org.au

Describe your job.

I’m a Boilermaker on the WestConnex project. My role is focused primarily on mechanical maintenance. This involves a variety of applications, from repair work and fabrication of all types of metal, through to pipe work, hardfacing and rebuilding cutter heads. I use a range of welding processes in my role, including manual metal arc welding, gas metal arc welding, gas tungsten arc welding, flux-cored arc welding, and brazing.

What inspired you to choose a career in the welding industry?

I’m actually not entirely sure what inspired me to choose a career in welding. There is no history of boilermakers in my family, so it wasn’t that I was following in the footsteps of any of my relatives.

I started a career in welding because I was given the opportunity to complete an apprenticeship through a family friend who had opened his own engineering company. During my apprenticeship I found that I really enjoyed boilermaking and welding. I’ve never looked back!

What do you believe is the biggest challenge for the industry?

The biggest challenge currently faced by our industry is keeping unions strong, so that they can continue to advocate for workers rights, particularly health and safety in the workplace. Every 10 days a construction industry worker is killed at work. It is vital that industry and

INSIDE THE WTIA: Q&A WITH A WTIA MEMBER

the unions work together to keep employees safe and reduce the rate of workplace injuries.

What do you believe is the biggest opportunity for the industry?

I think the biggest opportunity for industry is apprenticeships.

Boosting apprenticeship numbers and helping young people into long-term, successful careers in the construction industry, offers a number of benefits. It will help Australian industry address the shortfall of skilled workers that we are currently facing, and that is only going to get worse. Plus, it will mean that Australia can continue to build the high quality infrastructure needed by our growing population.

What is the most interesting project you’ve worked on? Why? The most interesting project that I’ve worked on would have to be the Sydney Opera House Vehicle Access and Pedestrian Safety (VAPS) project.

roundabout down to the new underground loading dock; and construction of lift shafts between the access corridors and ‘back of house’ facilities.

Being part of the construction of a tunnel underneath a huge landmark like the Sydney Opera House was enough to raise anyone’s eyebrows!

Plus, the views from the crib rooms were just awesome.

Who or what has inspired you the most professionally?

Working in the tunnel industry provides me a lot of inspiration.

We’re always undertaking high risk, high profile work, that will improve traffic congestion for commuters all around Australia.

What gives you the most satisfaction at work?

It would have to be rebuilding components that look unrepairable.

Making these components function

43

like clockwork and look like they’re brand new again gives me a great sense of satisfaction.

What are your greatest achievements?

One of my greatest professional achievements would have to be passing a weld test in the overhead position on a square to double v prep 40mm thick plate using flux core arc welding—it was not fun at all!

From a personal perspective, representing Australia in Futsul (indoor soccer) in Mexico was another great achievement, made even sweeter by the fact that I was the top goal scorer for the tournament. Skydiving is another of my greatest achievements.

But, the ultimate achievement for me would have to be the birth of my now two year old daughter Estelle— words really cannot explain that sense of achievement.

The $120 million VAPS project was part of the $152 million upgrade of the Sydney Opera House; the biggest building works on the site since the Opera House was opened in 1973.

The objective of the project was to separate heavy vehicle traffic from pedestrian traffic on the forecourt, thereby increasing public safety.

Some of the specific works included: construction of a 45m x 40m underground loading dock (cavern) located below the Sydney Opera House Monumental Steps and existing ground level loading dock; construction of two 80m long underground access corridors north from the north end of the loading dock; construction of a new 80m long underground ramp on the southern side of the forecourt to create a service vehicle access from the existing Macquarie Street

Louis Duchesne, a boilermaker on the WestConnex project was the first welder to be registered on the Australian Welder Certification Register (AWCR).

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AUSTRALIAN WELDING | JUNE 2017

Latest Issues from

The WTIA Hotline The WTIA offers a free ‘Hotline’ service to all Premium Corporate, Corporate and SMART Members. The purpose of the Hotline is not to provide a solution but to advise the enquirer on next steps. For further advice, the WTIA’s highly experienced welding consultants can speak to you on the phone or visit your site in person. If you have a Hotline query please fill in our online contact form and we will respond as soon as possible: www.wtia.com.au/hotline.

Welding Procedure Review The WTIA was recently asked to review the suitability of weld procedures used during the fabrication of a major bridge. In particular, the WTIA was asked to review the applicability of the WPSs after chemical analysis of the parent steel supplied showed that the boron content of the steel was different to that reported in the ladle analysis material certificate; the boron content was, in fact, above 0.0008%.

As per the Standards Australia Technical Specification SA TS 103:2016 (Structural Steel Welding – Limits on boron in parent materials), the boron content in the parent material must be <0.0008%. Section 4 of this specification states that, “Materials not compliant with this requirement will be deemed ‘nonpre-qualified’ for welding to AS/NZS1554:2014 Parts 1, 5 and 7”.

As the boron content of the steel supplied for the bridge was more than the specified limit of <0.0008%, pre-qualified status could not be assigned. Therefore, a full range of testing was required in order to qualify the weld procedure.

Soundness and properties were the important factors for the purpose of this procedure qualification.

Therefore, the two most important tests were needed: bend (to check the ductility) and tensile (to check the yield and tensile strength).

The tests conducted by the WTIA included: • Visual Test, as per AS 3978

• • • • •

Macro Test, as per AS 2205.5.1 Hardness Test, for Heat Affected Zone (HAZ), as per AS 2205.6.1 Charpy V-Notch Impact Test, as per AS 2205.7.1 Transverse Butt Tensile Test, as per AS 2205.2.1 Side Bend Test, as per AS 2205.3.1

As a result of these tests, the WTIA concluded that the steel was suitable for the intended application.

Because of its strong effect on hardenability, the presence of boron in steels introduces the requirement of stricter weld procedure control to avoid cracking. The effect of boron on weld metal structure and properties is more complex than for wrought steels.

Special care should therefore be exercised in welding of boron containing steels and in the selection of boron alloyed filler metals to obtain the structures and properties required for the weld metal and the HAZ. Avoidance of welding conditions that increase the susceptibility to HACC is of paramount importance.

Boron can be an extremely useful alloying addition to steels because of its potential to act as a powerful hardenability-promoter. However, the concentration of boron has to be carefully limited to prevent formation of boron containing compounds that can degrade the strength and toughness of the steel.

Alloying with boron is only a valid

strategy if it leads to a verifiable improvement in the properties of the steel. This is unlikely to be the case for low C structural steels of moderate strength levels (yield strengths of 250-350 MPa), which exhibit excellent ductility and weldability.

Addition of boron will not increase the strength unless a QT type heat treatment is applied, but it is likely to increase the potential for weldment cracking by promoting the formation of martensite in the HAZ. The WTIA’s advice on boron content remains as follows: 1. Members should satisfy themselves of the chemical content of steel to be welded including total boron. As not all suppliers list all the required elements on their test certificates, fabricators should request the information in writing from their supplier. If not forthcoming: a. Assume non-compliance if not disclosed; or b. Get their own chemical analysis performed; or c. Purchase steel from a supplier who will provide the required information.

2. Parent material containing total boron equal to or exceeding 8ppm should be treated as nonpre-qualified. When qualifying these steels, weld heat affected zone (HAZ) Charpy testing shall be performed in lieu of the parent plate Charpy tests (only applicable to Parts 1 and 5).

3. For steels containing total boron

45

INSIDE THE WTIA: HOTLINE REPORT

equal to or exceeding 8ppm advice should be sought from the parent material manufacturer regarding welding and preheat requirements.

The welding procedure is one of the principal methods for ensuring that a welded joint will perform in the service as intended. By eliminating the unknowns that can affect metallurgical properties and structural performance, the welding procedure establishes a major step towards avoidance of welding problems.

Comparative Analysis of AWS D1.1:2010 and AS/NZS 1554.1 and AS/NZS 1554.5 The WTIA was asked to review the suitability of American Welding Society (AWS) weld procedures, and comment on their acceptance in terms of compatibility to Australian Standard AS/NZS 1554.1:2014 (SP Weld Category).

The WTIA’s scope of the work included: • A list of the various discrepancies between the two standards for welding

•

• •

An explanation on how these discrepancies will impact on the performance in the welding practice, materials used, NDT and testing employed Commentary on the overall quality of product produced Commentary on the acceptance of AWS D1.1 in terms of the compatibility to Australian Standard AS/NZS 1554.1:2014

Three important variables, which cause most difficulty were examined by the WTIA: material, joint preparation and method of proving the welding procedure.

In addition, AWS D1.1 clearly defines the responsibilities of the Owner and Contractor in Section 6. It is the responsibility of the contractor to inspect and test as necessary prior to assembly, during welding and after welding to ensure that materials and workmanship meet the requirements of the contract documents.

Verification inspection and testing are the prerogatives of the Owner who may perform this function or, when provided in the contract,

waive independent verification, or stipulate that both inspection and verification shall be performed by the Contractor.

AS/NZS 1554 treats inspection as that carried out by the inspecting authority or the principal.

AWS D1.1 covers workmanship and other sections in greater detail than AS/NZS1554 Standard, including: • Design of welded connections • Workmanship – weld access holes, beam copes and cut surfaces in connection materials • Inspection – Contractor’s Inspection and Verification Inspection • NDT for Tubular Connections • Strengthening and repairing of existing structures • Fatigue life enhancement The WTIA determined that while the two Standards are not the same in all respects, they do overlap approximately 90% of the time.

Therefore, either of the Standards can be adopted and are acceptable for fabrication and welding of steel structures in on-shore and offshore.

46

AUSTRALIAN WELDING | JUNE 2017

SMART Industry

Groups Update The WTIA’s SMART (Save Money And Re-engineer with Technology) Industry Groups provide a forum for technology transfer and research and development, linking members with industry and research organisations. The WTIA works with SMART Group members to ensure they remain diverse and resilient in the ever-changing and increasingly challenging domestic and global markets. SMART Group members engineer innovative solutions that enhance safety, manage risk, reduce cost, and optimise operating efficiency, by: sharing the cost of implementing new technologies; developing best practices; and providing a forum to brainstorm common needs and effective solutions.

SMART Defence Industry Group Hosted by ASC, the SMART Defence Industry Group recently met in Adelaide. The meeting was hosted

by ASC, and chaired by Margaret Law (ASC’s Innovation Manager) and Mike Poynter (ASC’s Chief Engineer).

Judy Denison from the Centre for Defense Industry Capability

(CDIC) provided an overview of the Centre’s work, particularly its three core streams of activity: industry development; facilitating innovation and business competitiveness; and exports. The CDIC provides a range of support services for Australian companies, including business improvement, skills development, export and supply chain support, continuous improvement programs

and Defence market preparedness.

Moving forward, the CDIC will help to consolidate or create relationships between Defence industry prime contractors and local Australian businesses.

Remus Schwab-Russell (Project Manager Heavy Vehicles) from Rheinmetall provided an update

HOW TO REGISTER 1.

2.

3.

4.

5.

6.

Go to www.awcr.org.au Click on ‘Click Here to Register’.

Click on ‘Create An Account’.

Enter your contact details.

Verify your email address.

Login and complete your profile.

REGISTER NOW: AUSTRALIAN WELDER CERTIFICATION REGISTER

CR

Australian Welder Certification Register

02 8748 0100

|

info@wtia.com.au

|

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www.awcr.org.au

INSIDE THE WTIA: SMART INDUSTRY GROUPS

on the LAND 400 project, including Rheinmetall’s emphasis on increasing the engagement of local Australian businesses in order to boost the Australian Industry Content (AIC) of their vehicle.

LAND 400 aims to enhance the mounted close combat capability of the Army by providing armoured fighting vehicles with improved firepower, protection, mobility and communication characteristics to enable tactical success in the contemporary and future operational environment.

Rheinmetall’s vehicle for the LAND 400 project is the Boxer CRV. The Boxer is a state-of-the-art wheeled vehicle whose modular design permits a wide variety of mission specific configurations.

Alongside Brian Rungie (Executive Director Education) and Graham Gum (‎Senior Educational Manager Mining Engineering and Transport) from TAFE SA, Geoff Crittenden (WTIA CEO) presented on the launch of a pilot scheme for assessing and developing welder capability for the delivery of shipbuilding projects in South Australia using the Australian Welder Certification Register (AWCR).

ASC raised the issue of AS/NZS 3834 certification of welding subcontractors. During the ensuing discussion, Rhienmetall confirmed that any company seeking to join their supply chain must be AS/NZS 3834 certified. As a result,

47

the WTIA was asked to work with Defence prime contractors on auditing potential supply chain members, with a view to providing them with a pathway to AS/NZ 3834 certification.

energy providers) to AS/NZS 3834.

However, the view of all the power station representatives was that before they can insist on the certification of sub-contractors, they need to invest in their own certification.

Finally, new SMART Defence Industry Group member Baker & Provan—a metal fabrication, CNC machining and heavy engineering company based in Sydney—was welcomed to the Group. Their General Manager, Bob Findlay, gave a very well-received presentation on the work that the company is undertaking on military vehicles for the special forces.

As such, the WTIA has been asked to prepare a proposal to assess all WTIA power station members, with a view to providing a pathway to AS/NZS 3834 certification.

SMART APT Group Meeting The SMART APT Group meeting was also held in April, and was hosted

by CS Energy. Attendees included AGL Energy, Energy Australia, NRG Gladstone Power Station, Stanwell Corporation, CS Energy, Synergy, ANSTO, HRL Technology, ALS Global, Quest Integrity and Thornton Engineering.

During the meeting, attendees visited the Queensland University of Technology, and were treated to a presentation on Concentrated Solar Technology and the issues involved with high temperature salts used for heat transfer.

A major topic of discussion during the SMART APT Group meeting was the importance of the certification of sub-contractors (used by Australia’s

The Australian Welder Certification Register (AWCR) was also discussed.

Stanwell Power Station has agreed that, as part of their upcoming shut down, they will require all welders working onsite to be certified and qualified on the AWCR. Stanwell will set up a certification centre to help achieve this goal.

CS Energy and AGL also requested further details about the AWCR, which will enable them to enter into discussions with their prime contractors, with a view to having them registered on the AWCR. All these developments in the energy industry are a huge leap forward for the AWCR. Further Information For further information about becoming a WTIA SMART Group Member, contact us via: membership@wtia.com.au or 02 8748 0100.

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AUSTRALIAN WELDING | JUNE 2017

Member Directory The WTIA is dedicated to providing members with a competitive advantage through access to industry, research, education, government, and the wider welding community. When you join the WTIA you become part of a network of engaged companies and individuals, with whom you can share technology transfer, best practices, and professional opportunities. For further information, please contact membership@wtia.com.au or 02 8748 0100.

SMART (Save Money And Re-engineer with Technology) Industry Group Members AGL Energy www.agl.com.au 131 245 customer.solutions@agl.com.au

Transport and Main Roads (Queensland) www.tmr.qld.gov.au +61 7 3066 6358 TMRStructuralMaterials@tmr.qld.gov.au

Aloca World Alumina Australia www.alcoa.com +61 8 9316 5111 www.alcoa.com/global/en/contact

Newcrest Mining www.newcrest.com.au +61 3 9522 5333 corporateaffairs@newcrest.com.au

ANSTO www.ansto.gov.au +61 2 9717 3111 enquiries@ansto.gov.au

NRG Gladstone Operating Service www.nrggos.com.au +61 7 4976 5211 cmcguinn@nrggos.com.au

APT Management Services (APA) www.apa.com.au +61 2 9693 0000 apawebsitefeedback@apa.com.au

Stanwell Corporation www.stanwell.com 1800 300 351 www.stanwell.com/contact-us

ASC www.asc.com.au +61 8 8348 7000 David.Price@asc.com.au

Synergy www.synergy.net.au +61 8 9781 6720 Doug.Harman@synergy.net.au

Ausgrid www.ausgrid.com.au +61 2 4951 9555 cchiodi@ausgrid.com.au

Thales Australia www.thalesgroup.com +61 2 8037 6000 MaritimeBusinessSupport@thalesgroup.com.au

CS Energy www.csenergy.com.au +61 7 3854 7777 energyinfo@csenergy.com.au

Transport for NSW www.transport.nsw.gov.au +62 2 8202 2200 stakeholder.relations@transport.nsw.gov.au

Downer EDI Rail www.downergroup.com 1800 369 637 info@downergroup.com

Vales Point Power Station (Delta) www.de.com.au +61 2 4352 6111 info@de.com.au

Energy Australia www.energyaustralia.com.au 133 466 Wayne.Hill@energyaustraliansw.com.au

VicRoads www.vicroads.vic.gov.au +61 3 8391 3216 vicroadstechnicalservices@roads.vic.gov.au

IPM Operation & Maintenance Loy Yang www.gdfsuezau.com +61 3 5177 2000 www.gdfsuezau.com/contact-us/Contacts

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INSIDE THE WTIA: MEMBER DIRECTORY

Hardchrome Engineering www.hardchrome.com.au +61 3 9561 9555 office@hardchrome.com.au

Premium Corporate Members ALS Industrial www.alsglobal.com/au +61 2 4922 2400 powerservices@alsglobal.com

+61 3 9288 0888 info@mmg.com Monadelphous Group www.monadelphous.com.au +61 8 9316 1255 monadel@monadel.com.au

HERA www.hera.org.nz +64 9 262 2885 admin@hera.org.nz

Applied Ultrasonics Australia www.appliedultrasonics.com.au +61 2 9986 2133 info@appliedultrasonics.com.au

QENOS www.qenos.com +61 3 9258 7333 enquiry@qenos.com

Howden Australia www.howden.com +61 2 8844 9100 sales@howden.com.au

Arrium (One Steel) www.onesteel.com 1800 178 335 capital@onesteel.com

Quest Integrity Group www.questintegrity.com +61 7 5507 7900 Info-APAC@questintegrity.com

HRL Technology Group www.hrlt.com.au 1800 475 832 info@hrl.com.au

Austal Ships www.austal.com +61 8 9410 1111 info@austal.com

Santos www.santos.com +61 8 8116 5000 reception.ade@santos.com

Kemppi Australia www.kemppi.com +61 2 87852000 sales.au@kemppi.com

BlueScope Steel www.bluescopesteel.com.au 1800 800 789 steeldirect@bluescopesteel.com

Tronox Management www.tronox.com +61 8 9411 1444 info@tronox.com

Lincoln Electric www.lincolnelectric.com +61 2 9772 7222 sales@lincolnelectric.com.au

BOC www.boc-limited.com.au +61 2 8874 4400 contact@boc.com

United Group Resources (UGL) www.ugllimited.com +61 2 8925 8925 engineering@ugllimited.com

LMATS http://lmats.com.au +61 8 9200 2231 admin@lmats.com.au

Callidus Welding Solutions http://callidusgroup.com.au +61 8 6241 0799 info@callidusgroup.com.au

Water Corporation of WA www.watercorporation.com.au + 61 8 9423 7777 darren.vile@watercorporation.com.au

Main Roads Western Australia www.mainroads.wa.gov.au 138 138 enquiries@mainroads.wa.gov.au

CIGWELD www.cigweld.com.au 1300 654 674 enquiries@cigweld.com.au

Mitsubishi Hitachi Power Systems www.anz.mhps.com +61 7 3878 0888 general@anz.mhps.com

Coregas http://coregas.com.au +61 2 9794 2222 info@coregas.com

MMG www.mmg.com

Welding Industries of Australia (WIA) www.welding.com.au 1300 300 884 info@welding.com.au Wilmar Sugar www.wilmarsugarmills.com.au +61 7 4722 1972 info@wilmar.com.au

HELP SECURE THE FUTURE OF

AUSTRALIAN WELDING.

Welding Technology Institute of Australia

J OIN T H E W TI A TO DAY. 02 8748 0100

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AUSTRALIAN WELDING | JUNE 2017

Corporate Members

CQ Steel Industries: cqsteel.com.au Crisp Bros Haywards: haywards-steel.com Cullen Steel: cullensteel.com.au Custom Built Stainless: cbstainless.com.au D&L Engineering Services: fabinox.com.au DGH Engineering: dghengineering.com.au Diverse Welding Services: diversewelding.com.au E M Hauri: emhindustries.com.au E&A Contractors: ottowayfabrication.com.au Engineering Materials Evaluation: attar.com.au Excel Marine: excelmarine.net.au Extrin: extrin.com.au FIELD Engineers: fieldengineers.com.au Flexco: flexco.com.au Fortress Systems: fortressresistors.com G & G Mining Fabrication: ggminingfab.com Global Engineering & Construction: globalec.com.au Hifab Welding Supplies: hifabwelding.com.au Howell Davies: howelldavies.com.au HVAC Queensland: hvac.com.au INDT: indt.com.au Industrial Installation & Maintenance: iimaust.com.au Ingal EPS: ingaleps.com.au J Furphy & Sons: furphys.com.au Jacmor Engineering: jacmor.com.au JB Specialised Engineering: jordbellows.com.au JRâ&#x20AC;&#x2122;s Marine Engineering: jrsgroup.com.au Keppel Prince Engineering: keppelprince.com Knox Engineering: knoxeng.com K-TIG: k-tig.com LaserBond: laserbond.com.au LD Engineering Services: ldo.com.au Loadarm Australia: loadarm.com.au Loclur Engineering: loclur.com.au Mechanical Maintenance Solutions: mms.auz.net Mechanical Testing Services: N/A Melco Engineering: melcoeng.com.au Midway Metals: midwaymetals.com.au Millmerran Operating Company: intergen.com Monash University: monash.edu

3M Australia: 3m.com.au 4 Ken : 4ken.com.au A&G Engineering: agengineering.com.au Aben Technical Services: aben-tech.com.au Adept Inspections & Training: adeptengineering.com.au Aerison: aerison.com Aitken Welding Supplies: aitkenwelding.com Allstruct Engineering: allstructengineering.com.au Alltek Welding: alltek.net.au Allthread Industries: allthread.com.au Ancon Building Products: ancon.com.au Antec Group: antec.com.au ARL Laboratory Services: arllabservices.com.au Arup: arup.com Austal: austal.com Austral: australtechnologies.com.au Australian Infrastructure Manufacturing: ausim.com.au Australian Rail Track Corporation: artc.com.au Australian Welding Academy: australianweldingacademy.com.au Australian Welding Supplies: awsi.com.au Aztec Analysis: wga.com.au BAE Systems: baesystems.com Barker Hume Homes: N/A Baxter Institute: baxter.vic.edu.au BDR Stainless: bdrstainless.com.au Ben Baden Services: craneconnection.com.au Better Wear Welding: betterwear.com.au Bisalloy Steels: bisalloy.com.au BMC Welding: bmcgroup.com.au Bradken: bradken.com Brezac Constructions: brezac.com.au Broadspectrum: broadspectrum.com Brosco Enterprises: brosco.com.au Busicom Inspections & Training: busicomsolutions.com.au Caltex Refineries: caltex.com.au CCR Group: ccrgroup.com.au Coastal Steelfixing Australia: coastalsteelfixing.com.au CQ Industries: cqind.com

Newmont Asia Pacific: newmont.com Obadare: obadare.com.au Orrcon Manufacturing: orrconsteel.com.au OSD Pipelines: osdlimited.com Outdoor Fabrications: outdoorfabrications.com.au Precision Metal: precisionmetalgroup.com Purcellâ&#x20AC;&#x2122;s Engineering: purcells.com.au QSM Fabrication: qsmfabrication.com.au Quality Handling Systems: qhs.com.au Quality Process Services: qpspl.com.au Queensland Nitrates: N/A Radio Frequency Systems: rfsworld.com RCR Energy: rcrtom.com.au RJB Industries: rjb-industries.com Robot Technologies-Systems Australia: robottechnologies.com.au Ross Engineering: rossengineering.com.au Russell Mineral Equipment: rmeglobal.com S&L Steel: slsteel.com.au Samaras Group: samarasgroup.com Saunders International: saundersint.com Schenck Process Australia: schenckprocess.com SMW Group: smwgroup.com.au Smenco: smenco.com.au Snowy Hydro: snowyhydro.com.au Southern Cross Industrial Supplies: scis.com.au SP McLean Engineering: spmclean.com.au Steel Mains: www.steelmains.com Structural Integrity Engineering: siepl.com.au SWA Water Australia: swawater.com.au Tas Gas Networks: tasgas.com.au Testing, Inspection & Calibration Services: ticsndt.com The Bloomfield Group: bloomcoll.com.au Topline Steel Fabrications: N/A Trade and Investment NSW: industry.nsw.gov.au Vehicle Components: vehiclecomponents.com.au Victorian Testing & Inspection Services: victesting.com.au Walz Construction: walzgroup.biz WDT Engineers: wdtengineers.com.au Welding Guns of Australia: unimig.com.au Wicked Fabrications & Engineering: wickedfabrications.com.au

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INSIDE THE WTIA: UPCOMING EVENTS

Upcoming Events Whether you need to brush up on skills learnt years ago, want to try your hand at something new, or crave some networking opportunities, there is an industry event for you. For further information on any of the events listed below, or any WTIA events, please email events@wtia.com.au or phone +61 2 8748 0100.

July 2017 7th International Conference on Nanomaterials by Severe Plastic Deformation 2 to 7 July, Sydney www.nanospd7.com WeldTech Vietnam 4 to 7 July, Ho Chi Minh www.mtavietnam.com Royal Australian Chemical Institute 100th Anniversary Congress 23 to 28 July, Melbourne www.racicongress.com

Event Spotlight: International Conference on the Fabrication and Use of P91 Steel 11 to 12 October, Cairns, Australia

Sponsored by the WTIA and organised by ETD Consulting and the University of Wollongong, this conference will explore the relatively new 9Cr martensitic steels, P91 and P92, which have helped to increase power plant temperatures, pressures and efficiency for the new generation of plants. They are also used as replacement components in older power plants, where they have helped increase plant flexibility and reduced component fabrication, replacement and related costs. However, these steels can only achieve their design strength if they are heat treated strictly to the specified temperatures.

For more information, visit: www.etd-consulting.com

August 2017 YPIC 2017: Young Welding Professionals International Conference 17 to 18 August, Halle www.slv-halle.de September 2017 20th Annual Aluminum Conference 12 to 13 September, Portland www.aws.org Eurosteel 2017 13 to 15 September, Copenhagen www.eurosteel2017.dk Australian Steel Convention 2017 17 to 19 September, Gold Coast www.steel.org.au 7th IIW Welding Research and Collaboration Colloquium 19 to 20 September, Cambridge www.twi-global.com

6th International Conference on Material Science and Engineering Technology 20 to 22 October, Seoul www.icmset.com November 2017 5th International Conference on Scientific and Technical Advances in Friction Stir Welding and Processing 10 to 13 November, Metz www.fswp-2017.com

October 2017

15th Asia Pacific Conference for Non-Destructive Testing 13 to 17 November, Singapore www.apcndt2017.com

Welding Additive Manufacturing Conference 10 to 11 October, New York www.aws.org

The Stainless Steel World Conference & Exhibition 2017 28 to 30 November, Maastricht www.stainless-steel-world.net

December 2017 1st Asia-Pacific International Conference on Additive Manufacturing (APICAM) 4 to 6 December, Melbourne www.apicam2017.com.au WTIA & IIW EXAM DATES IWS and WTIA Welding Supervisor • 9 and 10 November 2017 IWI-B and IWI-S • 31 August and 1 September 2017 (depending on numbers) • 2 and 3 November 2017 For further information about WTIA exams, as well as qualification and certification requirements, please contact qnc@wtia.com.au.

WTIA’S EXPERT ADVISORY SERVICES

AND TECHNICAL SUPPORT: INDEPENDENT ADVICE YOU CAN TRUST The WTIA has a team of highly qualified welding engineers and materials specialists available to provide expert advisory services on all welding and materials related matters.

With expertise in a wide range of industries, from manufacturing to composites we have a unique capability to solve your joining problems. Our advice can help you substantially increase the operational life of your plant and equipment, thereby reducing your maintenance and repair overheads.

OUR AREAS OF EXPERTISE • • • • • • • • • • • • •

Welding procedure development Welding coordination and management systems Material performance and weldability Welding processes and related equipment Welding health and safety Failure investigation Expert witness in welding and related matters On-site welding technology assistance On-site auditing of welding quality systems Welding codes and standards Inspection and testing Non-destructive testing Mechanical testing

RESOURCES

• • • • • • • • • • •

Heat treatment in welding Welding quality management to ISO 3834 Welding specialists (IWE, IWT, IWS) for site work Pipelines-in-service welding, repairs and hot tapping Specialised welding and associated technologies (laser, ultrasonic peening and underwater welding) R&D and application of technology Engineering critical assessment fracture mechanics Structural and pressure equipment design Finite element analysis Weld cost estimating Life estimation

INFRASTRUCTURE

POWER GENERATION

Welding Technology Institute of Australia

HELPING SECURE THE FUTURE OF AUSTRALIA’S WELDING INDUSTRY. MANUFACTURING

DEFENCE

02 8748 0100 | info@wtia.com.au | www.wtia.com.au | Building 3, Level 3, 20 Bridge Street, Pymble, NSW 2073