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THE SOUTH AFRICAN MECHANICAL ENGINEER

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AN ENGINEER’S VIEW

Why Engineering Must Always Survive One does not have to be a rocket scientist to gather that the world is in trouble of a type not experienced by any previous generation, but I guess that goes for most types of threats that have engulfed society since the dawn of civilization. It is unlikely that we can go back into history to look for solutions other than to believe that certain fundamentals must prevail. One of them must essentially be an application of the laws of preservation of energy where we cannot take out more than we put into a closed system. Pretty basic stuff when associated with thermodynamics and physics lessons, but seemingly quite another matter when it comes to the behavior of society.

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he perverse antics of the investment banking community and those that believed in the ever growing value of assets that had no energy (value) actually added to them and the printing of dollars to bail out the losers, has left in its wake what must be no more than a painful correction to comply with the laws of energy. The dangers now posed by the dollar and the USA’s debt pile are horrific. When the USA sneezes, then the rest of the world gets a bad cold. We can call this the macro threat to SA because international trade will be affected. Chris Reay Chairman of the Working Then we go to our local scene and try to Committee: Communications evaluate if we can handle this pending (SA Institution of Mechanical debt tsunami only to find we have been Engineering) playing some bad rule breaking games of our own. Our (new) political dispensation learnt little from the old regime and in fact seemed to find quite a bit attractive about it even if assigned different labels.

If Engineers feel aggrieved at being unemployed then we can affix blame on the way society values creators World-wide, nations have failed to invest in the appropriate level of infrastructure to keep up with the burgeoning population. It has used up service facilities, minimized maintenance, splurged on quick returns, ignored sustainability, deceived and lied to voters who seem to take a while to realise it. Locally, SA has probably come first in class for messing up education from the ground up (let’s play OBE and close the teachers training colleges as well), disposed of its well developed intellectual capital (the best mining skills and artisan training in the world), replaced its ability to manage the infrastructure by providing comfortable salaried positions for its buddies (failed municipal service delivery), reducing food production (handing agricultural assets to those untrained to manage them) amongst others.

from taking it out? Politicians? Lawyers? Accountants? Social Scientists? Medics? Bureaucrats? Do these add energy or simply move it around and consume it? If Engineers feel aggrieved at being unemployed then we can affix blame on the way society values creators. How many industries actually take training of engineering resources seriously, and how many managements and HR departments find more value in preserving the company from the liabilities of Engineers over 55 or 60 than in using them to be productive and mentor the younger Engineers? No, rather go out and find those that are employed by others. Steal from Peter to pay Paul. It’s easier than training our own, because our neighbour steals them from us anyway. It is a zero sum game and when the tipping point comes, it is too late. There is then little or no critical level energy being added for the other professions to pilfer. To this add the incompetence of the politicians who are playing expediency games. Currently, with the combination of economic policy, labour policy, employment equity policy, education policy, skills development policy, SA is reaching the point of de-industrialisation and has slipped to a dismal low ranking in the world’s mining stakes. China’s faith in its ability to mould markets may derive from the fact that its leaders are mostly Engineers, trained to build from a plan. Eight of nine top party officials come from engineering backgrounds, and the practicality of their profession may help explain why they didn’t buy into risky (and Western) financial innovation. These ruling Engineers preside over a system that is highly process oriented and obsesses with performance metrics. In all this mess, what profession can best survive internationally? If someone can identify one other than engineering, then please do.

Who contributes to the adding of energy as distinct THE SOUTH AFRICAN MECHANICAL ENGINEER

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August 2011  VOLUME 61  NUMBER 8

Contents

Featured on the cover: Hansen Transmission South Africa Tel: (011) 397-2495, Email: ffourie@hit-shi.com www.hansen.co.za

Monthly Column 8 New Blood in Boat Building

Cover story 11 New Owners, Same Business

13 Listening to Customers Pays Off

All rights reserved. No editorial matter published in “SA Mechanical Engineer” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

29 Green Design 31 From Software to Water Treatment

Regulars 3 An Engineer’s View

Power Transmission

Copyright

Computers in Engineering

6 Institution News 15 SAINT

Pipes, Pumps & Valves

28 Nuclear Institute (SA Branch)

17 Missed Opportunities 21 Quick Pipe-Joining Solutions

34 SAIT

POWER GENERATION TODAY

37 Market Forum

23 Power from the Sun

35 SAPMA 46 On the Move

The monthly circulation is 4 242

Produced by:

Official Publication of THE SA INSTITUTION OF MECHANICAL ENGINEERING

PROMECH PUBLISHING, P O Box 373, Pinegowrie, 2123 Republic of South Africa Tel: (011) 781-1401, Fax: (011) 781-1403 Email: editorial@promech.co.za Website: www.promech.co.za

and endorsed by:

Managing Editor Susan Custers Editor Kowie Hamman Advertising Louise Taylor Administration and Circulation Manager Catherine Macdiva Production and Event Manager Zinobia Docrat DTP Yolanda Flowerday, Lilian Kemp Disclaimer PROMECH Publishing and The South African Institution of Mechanical Engineering as well as any other body do not take responsibility for the opinions expressed by individuals. Printed by: Typo Colour Printing, Tel: (011) 402-3468/9

 SA PUMP MANUFACTURERS ASSOCIATION  SA VALVE AND ACTUATORS MANUFACTURERS ASSOCIATION  THE SA INSTITUTE OF TRIBOLOGY  NUCLEAR INSTITUTE  SA INSTITUTE FOR NON-DESTRUCTIVE TESTING  NATIONAL SOCIETY OF BLACK ENGINEERS  INSTITUTE FOR CERTIFICATED MECHANICAL AND ELECTRICAL ENGINEERS  SOUTH AFRICAN ASSOCIATION OF CONSULTING ENGINEERS  ASSOCIATION OF SOCIETIES FOR OCCUPATIONAL SAFETY AND HEALTH

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THE SA INSTITUTION OF MECHANICAL ENGINEERING

Council 2010/2011 Office Bearers

President .................................................. G Barbic (George) Vice President .............................................. D Findeis (Dirk) National Treasurer ............................... KK Nyangoni (Kudzai)

Branch Chairpersons

Central ...................................................... M Cramer (Mike) Eastern Cape ................................................ W Rall (William) KwaZulu/Natal ................................................. J Moto (John) Mpumalanga Highveld.............................. L Odendaal (Louis) Western Cape ........................................... Dr Blaine (Debbie)

Portfolios:

Communications/Strategic Planning/ Specialist Group..................................................CD Reay (Chris) Education - Universities................Prof B Collier-Reed (Brandon) Education: Universities of Technology............... E Zawilska (Ewa) Membership .................................................... E Zawilska (Ewa) Professional Development Programme..........M Black (Malcolm) Technology Programme ................................. SZ Hrabar (Steve) To be confirmed....................................................A Roos (Andre) To be confirmed.........................................G Bartholomew (Bart)

Chief Executive Officer: Vaughan Rimbault National Office Manager: Anisa Nanabhay

PO Box 511, Bruma, 2026 Tel: (011) 615-5660, Fax: (011) 388-5356 Email: info@saimeche.org.za

Obituary: Professor Gerrie Thiart

Website: www.saimeche.org.za Membership: Central, Eastern Cape & KZN: membership@saimeche.org.za Membership: Western Cape: saimeche.wc@vodamail.co.za

Company Affiliates Alstom Power Service SA Babcock Africa Limited Bateman Engineered Technologies Bosch Projects Fluor SA GEA Air-cooled Systems Hansen Transmissions SA Hatch Africa Howden Power Howden Projects Industrial Water Cooling

Osborn Engineered Products SA Rotek Engineering RSD a division of DCD-Dorbyl S.A.M.E Water Sasol Technologies SEW Eurodrive Siemens SNC-Lavalin SA Spicer Axle SA Spirax Sarco SA Thyssenkrupp Engineering Transvaal Pressed Nuts & Bolts

Ultra-Flow Engineering Services MBE Minerals (SA) (Pty) Ltd (previously KHD Humboldt Vital Engineering Wedag SA) Weir Minerals Africa Megchem Eng & Drafting Services

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rof Gerrie Thiart, a professor in the thermofluids division of the Department of Mechanical and Mechatronic Engineering at Stellenbosch University, sadly passed away on 13 December 2010. He joined Stellenbosch’s Faculty of Engineering in 1991, lectured at the Military Academy in Saldanha from 2003 to 2006, and then returned to Stellenbosch in 2007. Prof Thiart completed his MSc in London and his PhD at Stellenbosch University. He had a great interest in marine engineering and computational fluid dynamics, topics that he lectured at both undergraduate and postgraduate level. He was greatly respected by his colleagues and by the many MScEng and PhD students he supervised in these fields. He will be remembered for his thoroughness, excellent academic progress, dedication and his solid contribution to his field. Gerrie had been a member of SAIMechE since 1979. He is survived by his wife, Christine, and two daughters.

Winder Controls

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THE SA INSTITUTION OF MECHANICAL ENGINEERING

John Orr Lecture 2011 “Bloodhound Supersonic Car” by Wing Commander Andy Green SAIMechE hosts this very prestigious “John Orr Memorial Lecture” each year to commemorate the achievements of Professor John Orr (1870 – 1954) in engineering education in South Africa. The history of this prestigious lecture dates back to 1961 when the first lecture was initiated to honor Professor Orr.

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his year the John Orr Lecturer will be Wing Commander Andy Green.

The lecture will be held at the following centres: Johannesburg: University of the Witwatersrand 15 November 2011 (Wits) Northern Cape: Kimberly (venue TBA)

17 November 2011

Cape Town: University of Cape Town (UCT)

22 November 2011

Port Elizabeth: Nelson Mandela Metropolitan 23 November 2011 University (NMMU) Durban: University of KwaZulu Natal (UKZN)

24 November 2011

More information will be available on the SAIMechE website shortly - www.saimeche.org.za, or contact Anisa at our National office on (011) 615-5660. The full notification including venue details and times will be emailed to all members shortly.

About John Orr

John Orr was born in 1870 in Lancshire and in 1887 entered Glasgow University where he graduated BSc in Mechanical and Electrical Engineering. He received further technical education at Coatbridge Mining College and the Royal Technical College, Glasgow. In 1893 he was awarded a Whitworth Medal and Exhibition, tenable at the Royal College of Science, London. He gained further practical experience in Scotland and England before coming to South Africa in 1897. Initially he was attached to the School of Mines of the South African College in Cape Town (which later became Cape Town University), but a year later went to the Kimberly Branch of the School of Mines as the Professor of Mechanical and Electrical Engineering. He retained his professorship when the school was transferred to Johannesburg in 1903 as the Transvaal Technical Institute. After several changes of name, this organisation became the University of the Witwatersrand in 1922, and Orr’s chair became the de Beer’s Chair of Mechanical Engineering.

Andy Green

Andy, Bloodhound SSC driver and team member, is the current holder of the World Land Speed Record, and the only person who has driven at supersonic speeds on land. Andy is a Fighter Pilot in the Royal Air Force. He is a mathematician (first class honours degree from Oxford University) and an integral part of the Bloodhound SSC team. The Bloodhound SSC project is an attempt to reach a speed of 1 000 mph on land, and break the current land speed record in 2012/2013. The location has already been decided as Hakskeen Pan in the Northern Cape. Bloodhound SSC Mission: To confront and overcome the impossible using science, technology, engineering and mathematics - To motivate the next generation to deal with global 21st century challenges.

In 1952 he resigned to organise mechanical education at the Witwatersrand Technical College, where he remained until he retired in 1945. He was awarded the honorary LLD by the University in 1936. A Mechanical Engineering Chair and a wing of the Mechanical Engineering Laboratory at the University of the Witwatersrand are named after him. He was a man of wide interests. He was President of the forerunner of the present South African Institution of Mechanical Engineers in 1908/09: President of the South African Association for the Advancement of Science in 1917, he helped to establish the South African Standards Institution in 1907, and was awarded an OBE in 1919, the Silver Jubilee Medal in 1935, and the Coronation Medal in 1937. He also directed technical training for the army and industry during World War 11.

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MONTHLY COLUMN

New Blood in Boat Building The Maverick at night in Cape Town harbour

South Africa has the third biggest catamaran building industry in the world. Yet there was room for one more new boat builder from Cape Town to enter the market and come to the fore, not only with a whole new luxury design, but a design that immediately raked in one award after the other.

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oat building reviews rave about the Maverick 400, calling it a benchmark catamaran that fills a gap in the market because it’s new and different. “SA Mechanical Engineer” visits the Maverick boat factory in Montague Gardens near Cape Town city to speak to Rudi Pretorius, the creator of the Maverick 400, a 40foot catamaran that has taken the yachting world across the globe by storm.

Changing careers Rudi Pretorius of Maverick Yachts

“I used to be in the supply chain and logistics industry, but after we

I wanted to start from scratch and come up with a whole new boat design altogether had our first yacht built to go on a world cruise, my wife and I got so hooked on boat building that we made a complete career change into the boat building industry,” he explains with a chuckle and a glint in his eyes. “Although we’ve owned several different yachts and have lots of cruising experience, the boat building side of the industry was quite new to us.

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“However, I recognised a gap in the market because every boat available had certain shortcomings. We set out to fill all the gaps in terms of what we really needed from a boat on long cruises where it becomes your home for extended periods of time,” adds Rudi. “Also, generally the market tends to use the same base design for catamarans over and over, by making slight cosmetic changes and giving the ‘new’ model a new name. I wanted to start from scratch and come up with a whole new boat design altogether.”

Design

After careful thought and lots of research, Rudi approached naval architect, Phil Southwell of Southwell Yacht Design to assist in designing the Maverick. “Usually the architect designs just the shell of the boat, but Phil and I got on very well and in the end he had a big hand in helping out with the interiors as well,” says Rudi. “All Maverick boats have the same basic shell, but when it comes to the interior layout and finishing, each boat is unique and usually built to each customer’s specific requirements. “They all have three cabins and two toilets while the main bed, for example, is cast into the mould and it can’t be moved elsewhere,” explains Rudi. “However, we wanted our bed to be an island bed so that the duvet could hang over the sides as you’d have at home and thus we designed it

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MONTHLY COLUMN

Rudi has built eight Maverick boats for owners from all over the world

to our specs. Normally boats only have capacity for 500 litres of fresh water, but we felt 1 000 litres should be standard. Two 22kW engines are fitted as standard, but this can be changed to what the client wants as well.”

The interior is customised to each owners’ liking

All the luxuries

The rest of the interior in terms of theme, luxuries and gadgets is entirely up to each individual. One of Rudi clients from Namibia, for example, wanted all the upholstery done in Kudu skin, complete with a bullet hole showing clearly, and that’s what he got. Another wanted a modern New York theme encompassing neon tubes and strip-lights flashing all over the place. Other options include 220 volts for home comforts such as a hairdryer, freezer and washing machine while the choice of ‘boy toy’ gadgets includes sophisticated shortwave computer modems for the built-in marine computers to do email, fancy navigation equipment and satellite phones, so you can stay in touch with loved ones on the other side of the world who have to work for a living.

Analysis

Rudi’s spends a lot of time with his customers to find out how they live and what they want out there on the ocean. “In terms of electricity, for example, I sit down with husband and wife and we start with their requirements as from midnight on a typical day,” explains Rudi. “The only thing drawing power is warning lights on deck until about seven in the morning when water goes on for coffee. Then the microwave is used to make breakfast, followed by a shower and the hairdryer, and so we take clients right through a typical day’s electricity use. Armed with this information, we add the appropriate generator,

solar power panels, batteries and an inverter to cater for their needs.”

Awards

In spite of hailing from a corporate background we quickly realise that Rudi has become a hands-on man as he takes us through the factory where two Maverick boats are being built. His commitment to excellence is clearly demonstrated in that the South African Boat Building Council awarded the very first Maverick the “South African Boat of the Year” award. The following year the Maverick was again voted “Boat of the Year”.

Another wanted a modern New York theme encompassing neon tubes and strip-lights Rudi has now built eight Maverick boats for owners from all over the world. “With economies picking up again now, we hope to continue to build on the success of the Maverick 400,” he concludes when we ask about future plans. “However, I’ve already seen other gaps in the market in terms of yet a bigger catamaran, but we’ll keep that under wraps for the time being.” Rudi Pretorius, Maverick Yachts, Tel: (021) 552-7752, Email: rudi@maverickyachts.co.za

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Comprehensive Climate Control in Agriculture and Fisheries.

Ideal Climate Control requires the ideal combination of components that fit and work together. Munters’ components when fitted together make up an unsurpassed system. With climate control expertise to match them as well as comprehensive local support, contact us today.

Climate. Controlled. Munters. (Pty) Ltd. 22 Angus Crescent, Longmeadow East, Modderfontein, 1610 . P O Box 4539, Edenvale, 1610. Tel: +27 11 997 2000 . Fax: +27 11 608 3503 . Web: www.munters.co.za . Email: info@munters.co.za Call us on 0860 MUNTERS 10 THE SOUTH AFRICAN MECHANICAL ENGINEER VOL 61 August 2011


COVER STORY

New Owners, Same Business

Forty-two years ago, Hansen Transmissions entered the South African industrial gearbox market and today the company can look back on a notable history with unique milestones including locally-developed drive solutions that are used across the globe.

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perating as an independent business unit, Hansen Transmissions South Africa was a direct subsidiary of Hansen Transmissions International in Belgium. In 2009 the industrial gearbox business unit of Hansen Transmissions International was spun off from the wind energy business into a separate corporate entity called Hansen Industrial Transmissions (HIT). This business unit has now been sold to Sumitomo Heavy Industries (SHI) Managing director, Fritz Fourie of Japan. The sale to Sumitomo consists of the industrial gearbox manufacturing business in Belgium, Hansen Industrial Transmissions, and includes all the assembly centres across the world: South Africa, Australia,

America, China, England and Brazil. In an exclusive interview “SA Mechanical Engineer” speaks to managing director, Fritz Fourie, about the consequences of this sale.

Joining forces will thus extend our market share worldwide “Even though Hansen Transmissions International has it’s roots in industrial gearbox manufacturing, the company changed its focus to the design and manufacture of gearboxes for the wind turbine industry. Industrial gearboxes comprised less than 20% of the turnover and was increasingly viewed as non-core business with research and development and capital investment channelled to the wind energy business. The sale to SHI is a good business fit because their range of industrial gearboxes is well-known in the East, South America and the

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COVER STORY

USA while Hansen on the other hand has a good market share in South Africa, Australia and Europe. The relationship between the two companies dates from the eighties when SHI built gearboxes in Japan under licence to Hansen,” says Fritz. “Joining forces will thus extend our market share worldwide.

Spares for all Hansen gearboxes made to date will be available for at least the next twenty years “Sumitomo also have complimentary products in the Cyclo geared motor range, Fenner type helical shaft mounted gearboxes and high precision geared motors. The sale will not have any immediate impact on the local company as the product offering, personnel and management stays the same.” he says. “Even our name will remain Hansen Transmission South Africa, but the trademark changes to Hansen Industrial Gearboxes.”

Synergies

Sumitomo and Hansen are carefully evaluating product synergies and market demands to ensure that integration of the Hansen business into Sumitomo maximises benefits to both customers and the SHI Group. “The Hansen brand is well-established, widely-used and well-respected and we’ll build further on this foundation into the future,” Fritz assures us. “To set the end-user’s mind at rest, the company has guaranteed that spares for all Hansen gearboxes made to date will be available for at least the next twenty years, so there’s no need for anyone to worry about this aspect at all.”

Huge product range

Although there is some overlap between the two companies, generally speaking Fritz explains, “In the

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larger gearboxes, over 700 kNm, as well as vertical parallel gearboxes for the mixer industry, Hansen is strong and Sumitomo does not really compete. On the other hand, Sumitomo has a full range of smaller gearboxes and a geared motor range which cover gaps in the current Hansen product range.” HIT believes in Sumitomo’s vision to become a world leader through innovation and globalisation in the power transmission market. Now that the acquisition is complete, HIT sees the opportunity to contribute significantly, with valuable resources and promising synergies, to the realisation of the SHI vision. Together, HIT and SHI represent two of the world’s most reputed brands in industrial gearboxes and both companies share the understanding of what it takes to serve demanding customer applications, to provide best in class customer service, to innovate and to grow.

Geared for success

From now on, SHI and HIT will evaluate diverse marketing topics for both companies on a global and regional level and will carefully consider product synergies and strategies to become a true global player. Yoshinobu Nakamura, President and CEO of Sumitomo Heavy Industries commentes on the acquisition, “In the past, SHI held a licence agreement with HTI. We considered the company our teacher of gearbox technology. From this historical point of view I am pleased that HIT and SHI are unified and can work together on the further development of our gearbox business for a solid global presence and, as such, commit to providing superior products and services while sharing the vision to exceed customer expectations.” Hansen Transmission South Africa, Fritz Fourie, Tel: (011) 397-2495, Email: ffourie@hit-shi.com

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POWER TRANSMISSION

Listening to Customers Pays Off Generally suppliers tend to ‘make’ customers buy what they want them to buy. In reality, the voice of the customer is king and suppliers who listen to this voice will have the competitive advantage.

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his is the core of a business philosophy David Brown Gear Industries adopted a few years back and today the company is reaping the benefits. In South Africa, the company is setting up service centres right on the doorstep of customers who have been asking them to do just that. “SA Mechanical Engineer” speaks to Darryl Elliott, aftermarket sales centre manager at David Brown, to get an update on their drive to extend services across the country.

We’ll start working on the third one which will be in the Middelburg area “Besides having the biggest open pit iron ore mine in the world at Sishen, the Northern Cape region has over twenty-two other mines stretching from Kathu all the way to the coast mining a number of

Darryl Elliott, aftermarket sales centre manager at David Brown

minerals including manganese, lime and diamonds,” he elaborates. “Considering that a new mine going up there right now will install gearboxes to the value of about R15 million, the gearbox population in the region is quite significant. For this reason we chose this area to set up our first service centre outside the Gauteng area.

Lots of gearboxes

The centres are equipped to cover 90% of typical gear unit repairs such as general machining, bearing changes and oil seal replacements

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“Since the opening of our first service centre in Benoni we have seen growing interest from clients wishing for us to support their needs throughout South Africa,” Darryl adds. “Now that the service centre in the Northern Cape is up and running, we’ll start working on the third one which will be in the Middelburg area. These centres are smaller than the main one at headquarters in Benoni, but will focus on specific client needs. Generally they will be doing repairs in terms of quick fixes to get plant up and going as quickly as possible. “Though the centres do not VOL 61

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have gear manufacturing equipment, they are equipped to cover 90% of typical gear unit repairs such as general machining, bearing changes and oil seal replacements,” explains Darryl. “Therefore, the centres are equipped with dedicated machines such as lathes, drilling machines and hydraulic presses and have spray booths as well as no-load testing facilities. The centres are overseen by a service manager, skilled artisans and assistants, but we’ll add specialist skills as each centre grows.”

Spares

Once a centre is established, Darryl and his team carry out surveys of each area to determine specific needs in terms of critical parts. “We’ll be working on all makes of gearboxes the customers in that region use,” Darryl explains. “We’re busy with the assessment of existing customers in the Northern Cape region now and will then stock up on critical spares for their specific popular gearboxes if they don’t already have stock as is often the case on mines in outlying regions. “But this is usually confined to the bigger mines which have extensive spares in stock and even the facilities to do the repairs. The majority of the other mines in the area do not. With our service centres being right there on their doorstep, we anticipate that we may in the long run take over this responsibility from the bigger mines by providing a full spares management and maintenance services for them,” says Darryl.

We’re also looking at an exchange system where we’ll have a complete gearbox in stock at the centre “In the interim, we’re also looking at an exchange system where we’ll have a complete gearbox in stock at the centre that can be exchanged to help out in an emergency while the customer’s gearbox is being repaired.”

Monitoring systems

Being part of a global group of companies that has no fewer than seven manufacturing facilities across the globe, means that even very scarce gears can be sourced from any one of these facilities relatively quickly. “While endusers today expect service and backup on machinery, they’re also been asking for preventative maintenance solutions,” says Darryl. “We’ve recognised this trend and after sizing up the various monitoring systems available for gearboxes and drives, we’ve partnered with a supplier. The electronic nature of condition monitoring equipment is new to us, but we’ve researched the market and after extensive testing on equipment to monitor temperatures, vibration, and power consumption, we’re satisfied that our service centres will offer the best comprehensive solution in terms of condition monitoring equipment.”

Facility expansion

“Major gear cutting and grinding work will continue to be done in Benoni where we’ve necessarily had to expand as well, especially with more work coming in from South America and Sub Saharan Africa,” concludes Bill Gorman, sales director at David Brown.

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POWER TRANSMISSION

“We’ve recently commissioned a new three metre carburising gas furnace to complement our Niles 3m diameter gear grinding capability, thereby tripling the in-house capacity of our heat treatment facility. To further supplement our grinding capacity, a brand new Niles grinding machine, fitted with full on-board measurement equipment capable of grinding gears up to 1.5m diameter, is arriving here this month and should be in operation soon.” Bill Gorman, David Brown Gear Industries, Tel: (011) 748-0000, Email: bgorman@ davidbrown.com

David Brown has all the facilities to work on all makes of gearboxes

The facility in Kathu in the northern Cape

The Education Village The 18th World Conference of NonDestructive Testing (WCNDT) to be held in South Africa from 16 to 20 April 2012 is billed to be an event for South Africa, Africa and the world. NDT personnel, scientists, researchers and equipment manufacturers are to meet in Durban. This gives an opportunity for people who are not conversant in NDT, as well as for learners and students to get a snapshot into the industry.

SAINT

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o assure that students and learners are afforded an opportunity to become acquainted with NDT and be informed about the possibilities of pursuing NDT as a career, the WCNDT marketing team has decided to incorporate an innovative new concept to the conference – an Education Village. SAINT approached the five largest training organisations who all have stands at the conference, showcasing NDT training and education and will be giving short introductory lectures in NDT in the exhibition hall. These lectures will address the fundamentals of NDT and afford the participants the opportunity to get a hands-on feel for what is involved in NDT. To make use of this opportunity visit the conference website (www. wcndt2012.org.za ) and make plans to be in Durban during the third week of April in 2012. See you there.

Robin Marshall, Tel: (011) 719-7919, Email: robin.marshall@protea.co.za / saint@ saint.org.za, www.wcndt2012.org.za

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SAMHYDRAULIK, which is one of the leaders in the field of hydraulic transmission, has been operating for over 25 years in the international market, offering a complete range of orbital hydraulic motors and power steering units, axial pumps and motors for medium and high pressure ranges, all characterised by excellent performances. SAMHYDRAULIK employs 120 people who operate inside a very modern and efficient plant that spans over 6 000 square metres to assure a high standard and flexible production capacity. The latest computer technology is used for both design and production, combined with strict quality control procedures during all production phases, which translates into innovative, reliable and functional products that meet the various needs of the market. Its ISO 9001 certification, held since 1994, is the result of a qualityorientated philosophy on which SAMHYDRAULIK has always based its operation.

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AXIOM HYDRAULICS (PTY) LTD Tel: (011) 334-3068 / 334-3086 Fax: (011) 334-4543 E-mail: axiomjhb@mweb.co.za

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17 Heidelberg Road, Village Main, Johannesburg, 2000 P O Box 260248, Excom, South Africa, 2023

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PIPES, PUMPS & VALVES

Missed Opportunities Despite unsatisfactory attendances at the conferences that ran in parallel with the exhibitions at Gallagher Estate, it was brisk business at this year’s combined Petro.t.ex Africa, Pumps Valves and Pipes Africa and WaterTec Africa trade shows, with quality visitors and excellent networking and business opportunities.

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A Mechanical Engineer” attended some of the presentations at the conferences. Petro.t.ex Africa dealt mainly with the state of the refinery sector in Africa including some overviews of the fuel retail sector in South Africa. “In future we will start promoting the conference earlier and make our prices for the conference more competitive,” says Bette McNaughton, director of Fair Consultants SA & Promocorp. “There should have been more fuel retailers. Topics discussed at this year’s conference include factors influencing the retail fuel sector, a look at what’s in store for the future of the sector and the impact of policies and regulations on the sector. In 2013 we hope to have all the players in this sector at the conference.”

Holding hands

On the WaterTec Africa front, conference attendance was a bit more encouraging, but chairman of the conference, Paul Runge, managing director of Africa Project Access says it was nevertheless unsatisfactory. “Given the importance of water and sanitation in Africa and the size of the exhibition, we could have had more people than the 40 odd we had at peak times,” he says. “What many water-related equipment and service suppliers don’t realise is that the huge number of projects going on in Africa right now present huge business opportunities. At the conference we had several of these projects reviewed by speakers from the different countries, “Our fellow African countries are searching for partnerships, they are reaching out and want to hold hands with other concerns that face the same THE SOUTH AFRICAN MECHANICAL ENGINEER

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challenges,” adds Paul. “A common problem is the recirculation of water and desalination challenges. A common thread is the huge drainage of skills in the water sector in particular. At the same time we learnt that there is more than enough financing available for water projects. It’s time for local companies to learn how these financing schemes work.”

The exhibition

On the exhibition side, it was a different story altogether. “We managed to attract several new clients, thanks to Pumps Valves and Pipes Africa,” says Seelan Pillay, General Manager of LVSA Valves. “The show has improved tremendously since 2009, it’s bigger and better.”

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one of the event organisers. “The three shows form an important networking hub for stakeholders in industry sectors that are critical to the infrastructure and economy of the country and the continent. Trade participation has been highly encouraging, and has provided visitors with a valuable interface with the industries involved.” Tyron Adam of Germany-based Netzsch says his company will definitely be back in 2013. The company supplies pumps, macerators, grinders and dosing systems. “Participating in this year’s show has been highly worthwhile. The show has provided an excellent platform for building relationships, both with existing and future clients. The visitors to our stand have all been ‘quality visitors’ and all the enquiries we received are prospective orders. One of our objectives for exhibiting was to build our brand and show the market ‘we are here’ and we’ve certainly done that.” “The turn-out this year has been absolutely fantastic,” said Mandy Reddy assistant director of Water Sector Management of the Department of Water Affairs. “People are constantly in-and-out of the stand.” “Africa’s Big Three has once again delivered solid, measurable results for our participants,” says John Thomson, managing director Exhibition Services,

WaterTec Africa exhibition, Penni Will, Tel: 011-783-7250, Fax: 011-783-7269, Email: sales2@exhibitionsafrica.com, Website: www.exhibitionsafrica.com Pumps, Valves & Pipes Africa exhibition, Serean Thomson, Tel: 011 783-7250, E-mail: marketing@exhibitionsafrica. com, Website: www.exhibitionsafrica.com

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Quick Pipe-Joining Solutions There are three main methods of joining lengths of pipe to form a pipeline, viz, welding pipe ends together, bolting pipes together with flanges or there’s the Victaulic way, a mechanical pipe-joining system. Both the welding and flanging methods are time-consuming and require specialists to make the joint a lasting one.

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he mechanical joining system, invented by Victaulic 85 years ago, is based on grooved technology requiring only two bolts and two nuts to clamp two pipe ends together in less than half the time it would take to weld the ends. To learn more about this system, now being marketed anew in South Africa, “SA Mechanical Engineer” speaks to Barry van Jaarsveld, regional manager of Victaulic in Africa.

Re-introduction

“The product is not unknown in South Africa as the

Grooved piping is the accepted method for underground and plant piping in North American mines and locally

Barry van Jaarsveld, regional manager of Victaulic in Africa

company did have a presence here some years back, but then closed shop under political pressure,” he says. “Four years ago they decided to re-establish a sales office in Johannesburg which now supplies the market through distributors throughout Africa. “Victaulic has been at the forefront of mechanical piping system innovations for over 85 years, providing numerous patented piping- related products that are in use today in multiple markets around the world,” Barry adds. “These solutions all stem from one basic concept, the original grooved end mechanical pipe joining system. This continues to be the most versatile, economical and reliable mechanical pipe joining system available, especially as ongoing research and development constantly adds new variations to the basic product concept.”

Accepted method

Apart from targeting the HVAC industry in South Africa, Barry is focussing on the mining industry throughout Africa where several mines have already standardised on the mechanical pipe joining system. “Grooved piping is the accepted method for underground and plant piping in North American mines and locally, the reasons for specifying mechanical piping systems are becoming more evident by the day,” he says.

The Victualic coupling system

“We’re the only company that supplies couplings for grooved piping systems capable of withstanding pressures of up to 27 500 kPa, specifically for the pumping of water and solids in applications such as backfill paste and sand.”

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The gasket is key

At the heart of the Victaulic system is a gasket, the only part of the coupling that comes into direct contact with the medium being pumped. Therefore, it’s made of a wide selection of materials in order to accommodate different mediums. The coupling housing performs several functions as an integral

couplings and features the same high-performance capabilities. Installation-ready technology, with no loose parts and no requirement to disassemble before installation, gives contractors, engineers and owners a competitive edge that is unmatched in the industry. “Our installation-ready product line does just that—helps our customers meet and exceed their schedules,” says Barry. “It offers a safer, flame-free solution, and reduces man hours.” The Style 177 QuickVic Flexible Coupling offers flexibility for expansion, contraction and deflection. It features a proprietary “EHP” gasket material for unmatched performance from -34°C to 121°C. The “EHP” gasket is geometrically optimised for unparalleled performance under pressure, heat, assembly, and stress relaxation. The new coupling is suited for HVAC, utility piping, process piping and mining applications and is rated up to 6900kPa. Available in sizes ranging from 50mm to 200mm it is designed for joining standard roll-grooved and cut-grooved steel pipe. Another recent innovation from Victaulic is its line of patented Advanced Groove System (AGS) products. “The AGS range of large-diameter rigid and flexible couplings, fittings, valves and accessories offers unprecedented performance and reliability due to its patented groove profile,” Barry explains.

Strongest system An installation with the mechanical coupling system

The gasket forms an initial seal as it is stretched over the pipe ends part of the pipe joint. It contains the gasket, which is fully enclosed, reinforcing and securing it in position for proper sealing. The housing also engages on the pipe around the full pipe circumference and creates a unified joint while providing the advantages of mechanical joining. “The sealing efficiency of our gaskets is such that the gasket forms an initial seal as it is stretched over the pipe ends,” explains Barry. “As the housing segments are tightened, the resilient elastomeric gasket conforms to the internal cavity of the housing, further enhancing the gasket’s seal against the pipe, in both pressure and vacuum conditions.” The gasket is pressure responsive, providing increased sealing action as the internal pressure is increased. The combination of these characteristics creates a permanent, leak-tight triple seal on a variety of piping materials including steel, stainless, aluminium, PVC, ductile iron and copper.

New technology

An extension of the Victaulic installation-ready product line, the Style 177 Quick Vic coupling installs in half the time as standard flexible grooved

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This product is ideal for mining, HVAC and industrial piping applications providing the strongest groove system available in sizes ranging from 350 to 1 524mm. It is a two-piece coupling housing which requires only two nuts and bolts as opposed to more than 16 required on a flanged equivalent. It also utilises a unique, wedge-shaped groove profile which increases end load capabilities, for pressures up to 2400 kPa.

Conversion service

Apart from a huge product range such as bends, T-joints, hole cutters and grooving machines for sale or for hire, the Victaulic services include a conversion service, of particular interest to South African companies as a solution for joining pipe diameters ranging from 20 millimetres to 1.5 metres. “Let’s say a pipe network for a project has already been designed with the intention of welding or flanging all the pipe joints,” Barry explains as a final remark. “We take these drawings and our Construction Piping Services (CPS) converts them free of charge to make all the joints mechanical couplings. We can then show the total installed time saving for the piping project and assist with accurate cost estimating.” It is a very compelling demonstration of how Victaulic will save time and money. Barry van Jaarsveld, Victaulic, Tel: (011) 956-6976, Email: barry.vanjaarsveld@victaulic.be

August 2011


POWER GENERATION

Produced by: PROMECH PUBLISHING, P O Box 373, Pinegowrie, 2123 Republic of South Africa Tel: (011) 781-1401 Fax: (011) 781-1403 Email: editorial@promech.co.za Website: www.promech.co.za Managing Editor Susan Custers Editor Kowie Hamman Advertising Louise Taylor Circulation Catherine Macdiva DTP Zinobia Docrat/ Yolanda Flowerday/Lilian Kemp Disclaimer PROMECH Publishing does not take responsibility for the opinions expressed by individuals. Printed by: Typo Colour Printing Tel: (011) 402-3468/9

Power from the Sun Sunlight is abundant, inexhaustible and a free energy source. Through technological advancement, the capture and processing of this energy has today become an increasingly feasible solution for sustainable electricity generation.

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here are several types of proven technologies to exploit thermal solar power for the generation of electricity, but, like wind power, the problem has always been to store either the generated power or the energy captured so that it can be used at a time when it is most needed.

Tower CSP technology for the first demonstration plant in Upington Copyright

All rights reserved. No editorial matter published in “Power Generation Today” may be reproduced in any form or language without written permission of the publishers. While every effort is made to ensure accurate reproduction, the editor, authors, publishers and their employees or agents shall not be responsible or in any way liable for any errors, omissions or inaccuracies in the publication, whether arising from negligence or otherwise or for any consequences arising therefrom. The inclusion or exclusion of any product does not mean that the publisher or editorial board advocates or rejects its use either generally or in any particular field or fields.

Technologies

Eskom has undertaken extensive research into these technologies. “SA Mechanical Engineer” speaks to Vikesh Rajpaul, Project Development manager - Concentrating Solar Power (CSP) at Eskom, to find out

Vikesh Rajpaul, Project Development manager - Concentrating Solar Power (CSP) at Eskom

about developments in terms of solar energy projects locally. “We’ve looked into all main proven technologies including the Parabolic Trough system, the Parabolic Dish principle, the Compact Linear Fresnel (CLF) system and Central Receiver, or Power Tower, and our studies indicated that both the Tower and Trough technologies are promising options” he explains. “The decision to go ahead with Tower CSP technology for the first demonstration plant in Upington stem from the fact that tower as opposed to parabolic trough has higher potential for local manufacture, higher temperatures thus higher efficiencies, lower levelised energy cost and better scope for capital cost reduction in future plants due to economies of scale. In addition, the power generation side of this technology closely matches that of a conventional fossil power station, technology we’re familiar with and have experience in.”

The parabolic trough system

The tower CSP

The most mature CSP technology is the parabolic trough collector, but alternative technologies are rapidly coming to the fore, such as Linear Fresnel collector plants with flat mirrors and tower plants with flat or slightly curved mirrors called heliostats. The basic principle is the same for all three plant

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technologies where mirrors concentrate the incident solar radiation onto a receiver where it is converted into heat which, in turn, is used to produce steam to drive a steam turbine. Heat storage systems like molten salt tanks provide for power supply even during unfavourable weather conditions or at night. They significantly increase the capacity factor of the plant and allow for predictable generation and dispatch of electricity. Parabolic systems use trough-shaped mirrors to focus sunlight onto an absorber tube, the receiver, placed in the trough’s focal line. The troughs are designed to track the sun along one axis, predominantly north-south. The receivers contain a heat transfer fluid such as synthetic thermal oil which is heated by the focused sunlight on the receiver. It is circulated in these tubes and pumped through heat exchangers to produce steam to drive a steam turbine generator system.

It can be used to generate electricity in bad weather or at night Limitations

The parabolic trough technology is currently the best proven and most used technology, even though the live steam parameters are lower than in CSP tower plants. “This has contributed to our preference for the tower system,” explains Vikesh. “The limitations of the trough system, in which a synthetic oil as medium is the most common, is that you can’t heat it above about 400ºC as chemical degradation occurs above this temperature. “Standard conventional power stations operate at around 540ºC while the trough system effectively only goes up to about 370 to 380ºC,” explains Vikesh. “This means you would not be operating as efficiently as you would in a conventional power station. However, with the tower collector system, steam temperatures around 540oC can be reached,

This 10-MW power tower facility known as Solar Two near Barstow, California, demonstrated molten salt storage

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Compact linear fresnel (CLF)

taking the Rankine cycle efficiency level up to that of a conventional power station.

Flexibility

Apart from the advantage of solar power towers in that they’re able to provide higher temperatures and thus superheated steam, the system is more flexible when it comes to plant construction, because the heliostats do not need to be sited on an even surface. A solar tower system consists of circular array of heliostats which are sun-tracking mirrors. The heliostats concentrate sunlight onto a central receiver at the top of a tower. The heat transfer medium, which can be water, molten salt or air, in the receiver absorbs the thermal energy and transfers it into the steam cycle similar to a conventional steam power station where it generates superheated steam for the turbine. “Another advantage over the parabolic trough or Fresnel collector concept is that the working fluids on the central receiver is limited to a smaller area, and the heat transfer medium does not have to be piped around a large solar field as is the case with the trough system,” says Vikesh. “In addition, a spillage in a molten salt system is easier to manage from an environmental perspective, than a leak in an oil system.”

Molten salt

Another choice that had to be made for the Upington plant was the heat medium. Here Eskom opted for molten salt over oil or water. Molten salt as a thermal energy storage method retains the thermal energy collected by the solar tower so that it can be used to generate electricity in bad weather or at night. This has already been proven in various CSP plants in Spain and the USA. The molten salt is a mixture of 60 percent sodium nitrate and 40 percent potassium nitrate, commonly

called saltpetre. It is non-flammable and non-toxic, and has already been used in the chemical and metals industries as a heat-transport fluid, so experience with such systems also exists in nonsolar applications. The salt freezes at 221°C. It is kept liquid at 288 °C in an insulated ‘cold’ storage tank. The liquid salt is pumped through panels in a solar collector where the focused sun heats it to 565°C and it is then sent to a hot storage tank. When electricity is needed, the hot salt is pumped to a steam generator to produce superheated steam for a turbine generator as is used in any conventional coal, oil or nuclear power plant. The biggest advantages of the direct two-tank molten salt storage system besides the fact that there is no need for expensive heat exchangers between the HTF and the storage fluid, is the high temperature range of the storage system which is nearly 300 K. Thus, for the same storage capacity there is only about one third of salt inventory required in direct systems for solar tower applications compared with

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the (indirect) storage system applied in parabolic trough power plants, which have only a temperature range of 100 K in the storage system,

Past experience

“Keep in mind that from the steam generating stage this type of plant works exactly like a conventional power station. We’ve essentially just taken the ‘dirty’ side of coal handling and burning out of the process,” adds Vikesh. “Therefore power generation part of the process won’t be a learning curve for us, it’s just a matter of getting to know and fine-tune the energy capturing and storage side of a tower CSP system to our specific conditions in South Africa. That’s why the Upington project is regarded as a demonstration plant, a project from which we not only intend to learn, but to evaluate, determine and benchmark the necessary specifications for the plant fleet of the future.” The Upington project may very well bring forth some interesting challenges as it is the first tower collector CSP plant of the size that Eskom intends to put up. “We’re aspiring to build a 100 MW plant, something that has not been done with this technology ever before,” Vikesh remarks in conclusion. “There are risks associated with scaling up from the current plants using this technology. Given Eskom’s intention to procure the plant through an

Central receiver / power tower

We’ve essentially just taken the ‘dirty’ side of coal handling and burning out of the process EPC (Engineer, Procure, and Construct) process, and that component, system and performance guarantees will be available from suppliers in all the plant areas, the technical risk, although high, is considered to be manageable.” Vikesh Rajpaul, Eskom, Tel: (011) 629-5312, Email: vikesh. rajpaul@eskom.co.za

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NUCLEAR INSTITUTE (SA BRANCH)

Mayo Deficiency

A few days ago I received an agitated email from an old nuclear friend of mine to the effect that Koeberg had gone mad. He was reconsidering his support for nuclear generation in South Africa. The reason had to do with the station’s incident reporting system.

A

Problem Notification (PN62886) had been raised, just conceivably tongue in cheek, to the effect that a tuna mayonnaise sandwich purchased in the site cafeteria had contained insufficient mayo. The matter was assessed and it was established that the cafeteria staff had acted appropriately in that they had offered a replacement unit. The incident was designated NAC (No Adverse Condition) and filed for trending.

Believe it or not

John Walmsley

The anti-nuclear lobby has in the past complained about the number of incidents reported at Koeberg – now, believe it or not, around six thousand per year. But even that should not worry my head-shaking friend, rather the reverse. The World Association of Nuclear Operators (WANO) requires that even the most trivial incidents or deficiencies be reported and, if necessary, investigated. The idea is to reinforce a regime of zero tolerance and, importantly, to highlight trends. If too many trivial incidents start to appear in any area, action can be taken before something more serious happens. My friend up there in Muckleneuk can sleep easy.

I challenged a contact at Koeberg along those lines Everyone enjoys a good disaster and since Fukushima there has been a surge of interest in matters nuclear. To my knowledge there have been seven lectures and panel discussions in the Cape Town area alone. One of them was organised jointly by WESSA, the Wildlife and Environmental Society of South Africa, and the Greater Cape Town Civic Association. To be strictly accurate, the event was held to discuss energy in general but inevitably Fukushima intruded. The Chairperson of the Koeberg Information Forum began her contribution, the last of the Saturday morning, with the Fukushima evacuation zones superimposed on a map of Cape Town. She then reviewed every anti-nuclear argument known to Man. She had been invited to speak, the Chairman explained, because Eskom had ignored emailed and verbal requests to participate. An opportunity for some positive nuclear PR thus became a PR debacle. There was no one from Eskom even in the audience. A few days later, the Institute for Security Studies’ Corruption and Governance Programme (curiously) organised a similar event. Peter Bester of the National Nuclear Regulator gave an appropri-

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ately non-partisan account of NNR activities while the Greenpeace representative and heavyweight anti-nuclear campaigner David Fig spoke against. Whenever decisions go the pro-nuclear way the antinuclear lobby complains that the process has been undemocratic. Dr Fig duly attacked the decision by the IRP2010 committee to include 9600 MW of new nuclear generation in the 2030 energy mix. The EIA process is also evidently deeply flawed.

Grey beards

In the back row sat four nuclear grey-beards, three late of Eskom, one from NECSA. I had, in fact, received an email from a NECSA executive drawing my attention to the meeting and suggesting that I muster a nuclear presence. Send in the pensioners! Our attendance demonstrated, not least to the meeting chairman who is also the chairman of the Parliamentary energy portfolio committee, that there is a pro-nuclear point of view. A valuable contact was made. In ten years in Cape Town I must have attended at least twice that number of anti-nuclear debates, lectures and, particularly, film shows. With one exception, I have never seen anyone that I recognised from Koeberg or from Eskom in general. Are they all nine to fivers with no real interest in the job? If so, shut the thing down. On the day after the ISS meeting I challenged a contact at Koeberg along those lines. There’s no point in going, he said, we’re not allowed to speak. Correctly or otherwise, that’s certainly the perception. Equally certainly, no nuclear employee would dare risk responding to anti-nuclear material in the newspapers. I don’t enjoy complaining. The point of all this is to illustrate the obstacles to ‘public education’ that the nuclear industry puts in its own path. Another was illustrated by an article defining the ‘case for nuclear’ that I recently drafted for NIASA - which all too few know stands for the Nuclear Industry Association of South Africa. In it I described wind energy as intermittent and unreliable. I got away with ‘intermittent’, I think, but ‘unreliable’ had to come out. I had indeed forgotten a fairly recent agreement between NIASA and renewables vendors to refrain from denigrating each other’s products. I fully support that principle but I’m also very much aware that the public is regularly assured that, given a few years, wind and solar energy can replace nuclear and fossil entirely, even for base load operation. What a gift to the anti-nuclear crowd if people who speak for the nuclear industry cannot even mention the words unr*l*able or, perish the thought, sp*r*dic. John Walmsley

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Green Design Consumers the world over are demanding and choosing products that have the minimum impact on the environment, not only in terms of their manufacture but also their use and ultimately, their disposal.

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n light of this growing trend, product designers and developers need to build environmentally-responsible products in order to maintain and grow their local and international markets. It’s no surprise then to find that product design software developers, like SolidWorks, have come up with a solution to assist their customers in developing sustainable products.

“SA Mechanical Engineer ” speaks to Freek van den Berg, director of Mecad Systems and the distributors of SolidWorks software in South Africa, to find out more. “The SolidWorks SusFreek van den Berg, director of Mecad tainability module allows users Systems to measure the environmental impact of the products they design,” he says. “This feature is fully integrated into SolidWorks and provides real-time feedback on carbon footprint, total energy consumed, the effect on water and air. “It’s all about Lifecycle Assessment (LCA),” adds Robert Pereira, product manager at Mecad. “LCA is a method to quantitatively assess the environmental impact of a product throughout its entire lifecycle, from the procurement of the raw materials through to production, distribution, use, disposal, and recycling of that product. This Robert Pereira, product manager at Mecad programme module utilises

Provides real-time feedback on carbon footprint, total energy consumed, the effect on water and air an extensive database to calculate the four main sustainability metrics used in industry.”

The metrics

First port of call is measuring the carbon footprint of the product. This reflects the amount of carbondioxide and other gases which result from the burning of fossil fuels. The carbon footprint acts as a proxy

for the larger impact factor referred to as Global Warming Potential (GWP), the factor blamed for problems like loss of glaciers, extinction of species, and more extreme weather. Next is total energy consumed which is a measure of the non-renewable energy sources associated with the part’s lifecycle in units of mega-joules. This impact includes not only that of electricity or fuels used during the product’s lifecycle, but also the upstream energy required to obtain and process these fuels, as well as the embodied energy of materials which are released when burned. The efficiencies in energy conversion such as power, heat, or steam, are also taken into account during this calculation.

The simple and powerful solution for sustainable product design

Air and water

The third metric is air acidification. Sulphur dioxide, nitrous oxides and other acidic emissions cause an increase in the acidity of rainwater, which in turn affects the quality of lakes and soil. These acids can make the land and water toxic for plants and aquatic life. Acid rain can also slowly dissolve manmade building materials such as concrete. This impact factor is typically measured in units of either kg sulphur dioxide equivalent (SO2e), or moules H+ equivalent. Finally there’s water eutrophication which basically tracks when an over-abundance of nutrients is added to a water ecosystem. Nitrogen and phosphorous from waste water and agricultural fertilizers cause an overabundance of algae to bloom which then depletes the water of oxygen and results in the death of both plant and animal life. This impact factor is typically measured in either kg phosphate equivalent (PO4e) or kg nitrogen (N) equivalent.

Database

“The data used by SolidWorks Sustainability is pro-

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with the GaBi software, is used in our Sustainability offering.

Versions

“The programme is available in two versions, Sustainability and Xpress which will be included in every seat of SolidWorks 2010 at no additional charge,” says Robert. “The Xpress version can do the LCA of individual parts, has the ‘find Similar Materials’ feature, has an environmental impact dashboard and can do customisable sustainability reports. The full version can do the LCA of assemblies, it supports configurations with expanded reporting capabilities for assemblies and the user can also input energy consumption and transportation methods for consideration.” Sustainable design

The data used by SolidWorks Sustainability is provided by PE-International of Stuttgart in Germany vided by PE-International of Stuttgart in Germany,” says Robert. “They have provided software and consulting services in sustainable design and LCA for almost 20 years and their database, together

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“Several South African companies have shown a keen interest in this feature of our software,” Freek says in conclusion. “These are companies who have realised that if they want to do work for international companies and markets, they need to seriously consider environmental issues. They have to start viewing ‘green’ as a competitive differentiator in an increasingly ‘green’ marketplace.” Robert Pereira, Mecad Systems, Tel: 086 111-2236, Email: robert@mecad.co.za

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COMPUTERS IN ENGINEERING

From Software to Water Treatment Any vendor of engineering software worth his or her salt is bound to get involved in the business of his customers because CAD, simulation and analysis software packages are no longer stand-alone solutions purely there to fulfil the single task of designing or simulating a design. Rather, packages are now an integrated management tool of the entire engineering business. Therefore the package is often tailored by the vendor to each company’s set of rules and unique methods of operation.

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his is pretty much how Resonant Solutions evolved from a software vendor and software service provider to the multidisciplinary engineering company of today. “SA Mechanical Engineer ” visits the company in Centurion where yet another engineering branch, Resonant Water, has been launched under the umbrella of the original company.

Reactivated sludge is mixed with a bio-filtration system

Olof Vorster, one of the directors of Resonant

“From just a handful of design and analysis engineers delivering consultative design analysis a few years ago, we’ve grown to a staff of over twenty specialists in no fewer than four companies under one roof,” Olof Vorster, director of Resonant Solutions, kicks off. “Resonant Environmental Technologies is one of the first additions that took our consulting and design engineering offering into turnkey projects where we also manage the fabrication and installation of plant in the gas purification industry.”

The process flow of the system

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Marno Raath, the director heading up Resonant Water

The system as set up in Russia

After preliminary mechanical treatment (separation of suspended solids and sands); Sewage is drawn into mixing chamber (1) where sewage is mixed with the sludge liquid coming from aerotank-settler (2). The mixture of sewage and sludge is drawn with circulation pump (3) from the mixing chamber to the biofilter sprinkling system consisting of spouting chutes with outlet pipes (4) and of reflecting disks (5). The falling water jets are broken upon the disks, thus irrigating biofilter feed (6). The liquid leaving the biofilter is collected with tray (7) and delivered by air-stripping towers (8) to aeration zone (9) of the aerotank-settler.

Russia

This offshoot evolved from Resonant’s work on projects in Russia that turned into delivering turnkey EPMC projects which originated from doing a comprehensive flow analysis of the Russian plant. Resonant quickly realised that they also needed design engineers on the automation side to build intellectual property into their designs and in order to distinguish the company in the market. This gave birth to a third company, Resonant Automation.

An energy consumption saving of about 25% compared with a conventional treatment plant The fourth company, Resonant Water, also has a strong Russian link in that one of the technologies the company is now marketing in South Africa emanates from this country. “We’ve come to understand how the Russians think and the way they do business,” says Olof. “This provided an avenue to approach other companies in Russia when we started looking for waste water purification technol-

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ogy we could bring to South Africa under the wing of our new company.

Unique technology

The focus area for Resonant Water is pump stations and waste water treatment plant. “In terms of waste water treatment, we found unique new technology in a process where reactivated sludge is mixed with a bio-filtration system,” explains Marno Raath, the director heading up Resonant Water. “This process, developed by the Rostov Institute in Russia, is so new that it hasn’t even been defined properly yet in terms of engineering processes. “Basically it’s a closed system which is way more efficient than any of the normal treatment methods. Being a closed system has a major advantage in that it can be built right inside residential areas without causing the usual unwanted odours associated with traditional sewerage works.

Savings

“Other major advantages include an energy August 2011


COMPUTERS IN ENGINEERING

consumption saving of about 25% compared with a conventional treatment plant of the same capacity,” adds Marno. “The fact that we’re using natural biodegrading treatment processes and that the system works with gravitation, contributes to the saving in energy consumption. For example, a plant Analysis on 5.2 MW electrical motor processing 7 500 litres of waste water a day only needs around 0.35 kW for the to give them the green light. Rostov-type plant. This power can easily be gener- “With our system, they can build their own treatated purely from a solar panel system. ment plant within the development. In fact, one

We’ve also had huge interest from property developers “In terms of land space, the treatment plant can be built on a surface area three times smaller than the area required to build a traditional treatment plant of equal capacity,” he says. “What’s more, the resultant effluent from the plant is of a much higher quality than the water you get with any of the conventional treatment methods. Also, the sludge can be used as a fertiliser as is, without the need for any treatment as would be the case with a conventional plant.”

developer just got the go-ahead to build over 3 000 houses because he’ll be using our system to build the sewerage treatment plant for his development.” Marno Raath, Resonant Water, Tel: (012) 665-0990/5, Email: marno@resonant.co.za

The process

After preliminary mechanical treatment for the separation of suspended solids and sands, the sewage is drawn into a mixing chamber where it is mixed with the sludge liquid coming from an aero tank-settler. The mixture of sewage and sludge is drawn with a circulation pump from the mixing chamber to the bio filter sprinkling system consisting of spouting chutes with outlet pipes that lead onto reflecting disks. By gravitation the falling water jets are then broken up on the disks, thus irrigating bio filter feed. The liquid leaving the bio filter is collected in a tray and delivered by air-stripping towers to the aeration zone of the aero tank-settler. From the top of the tank, clean water then flows out to settling dams.

Go-ahead

“Our first local plant is being manufactured right now,” Olof says in conclusion. “It is for a game lodge where the client wants to get rid of his septic tank system for environmental reasons. We’ve also had huge interest from property developers whose development plans often get rejected because the municipality does not have the sewerage capacity THE SOUTH AFRICAN MECHANICAL ENGINEER

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SAIT

Everyday Friction We are always talking about the detrimental effects of friction, leading to wear, increased temperatures and even component failures, but how often do we reflect on its impact on our normal lives? With a lot of global attention on improving efficiencies and reducing our impact on the environment, we need to reduce friction, right? Maybe…

of friction to slow down these vehicles from their top speed of 325km/h to a cornering speed of less than 100km/h was really brought home at 2am while sitting at Arnage corner, where car after car came past with brake discs glowing in the night. In this case, the more friction the better, although the limit of frictional grip between tyre and track must not be exceeded. No ABS on these cars, and drivers who got it wrong left trails of tyre smoke behind to indicate to the fans of their errors. I am sure you will be pleased to know that a few cars got it VERY wrong, and ended up in the tyre wall, much to the delight of the crowds! So, in some cases we work hard to reduce or eliminate friction, other cases we harness the benefits of friction to enable us to achieve our goals. I hope I get the chance to examine this tribological event next year! David Beard SAIT Committee Member

The winning Audi at Mulsanne Corner

I

was lucky enough to attend the Le Mans 24 Hour Race last weekend, and managed to stay awake for the whole event; a truly spectacular achievement (the race, not staying awake) and incredible that such highly-tuned machinery can perform so close to the limits for 24 hours, clocking nearly 5 000kms in the process. I’m sure it was time for a service after that…! And what about the roles played by friction? A Corvette outbreaks himself On the one hand, the Peugeots were slowly reeling in the remaining Audi as they had Upcoming course dates the more fuel-efficient (diesel) engine, and were able to stop Lubrication Engineering 74 – 5-day course, 15 – 19 August 2011, less frequently. Audi, however, Cape Town were able to lap faster, but had to stop more often. So, Introduction to Lubrication Engineering – 1-day course, 7 September an efficient engine, or more 2011, Johannesburg speed? It seems that Audi had Introduction to Wear & Materials – 1-day course, 8 September the better answer, winning the 2011, Johannesburg race by a mere 13 seconds!

Really brought home

On the other hand, the use

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For more information contact Gill Fuller at 011 802-5145 or at secretary@sait.org.za.

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SAPMA

Pimp My Pump This monthly column, submitted by SAPMA (SA Pump Manufacturers Association) will guide and advise readers on the in’s and outs of the pump world.

F

or many OEM,s and end-users the perception that variable speed drives are complex and expensive, has prevented them from purchasing and using variable speed drives for their applications. In a nutshell, the basics of a variable speed drive are very simple. The VSD is connected to your incoming line; it then converts the voltage to DC and then pumps it out to resemble a sine wave. This is known as pulse width modulation (PWM). By doing this we have control of the voltage and frequency that is supplied to the motor. What does this control mean; it means we can control the speed and voltage supplied to the motor so the motor only utilizes what it requires to perform its function optimally. In pumping applications there are two main types of pumps, centrifugal pumps and positive displacement pumps. Let us consider centrifugal pumps first. Laws of affinity

The result of the law of affinity is reducing the flow by 1/2 (speed by 1/2) reduces the power consumption to 1/8 and the maximum height to 1/4

Running at half speed , shaft torque = 100 %

Thus instead of running the motor at full speed and then reducing flow rate by throttling with the use of valves it makes more economical sense to control flow rate by controlling the motor speed.

According to the U/F curve the output voltage at 25 Hz is 200 Volt

When we consider positive displacement pumps, the same rule does not apply as these pumps follow the law of constant torque. However there is still a large saving that can be achieved by using a variable speed drive as shown in the example below:

Running at full speed, shaft torque = 100%

In conclusion with the constant increases on electrical costs, it is necessary for all users’ of electric motors to evaluate means of reducing these costs.

According to the U/F curve the output voltage at 50Hz is 400 V (note for a 400V supply) Output Power P1 = Volts x Current x Cos 0 x Sqrt (3) Output Power

P1 = 400 x 94 x 0.91x 1.732

P1 = 59,262KW

Output Power Sqrt (3)

P2 = Volts x Current x Cos 0 x = 200 x 94 x 0.91 x 1.732 P2 = 29,631 KW

The result is with the same torque a speed reduction of 50 % reduces the power consumption by 50 %.

Variable speed drives offer the most cost-effective method to achieve maximum saving and efficient operation. SAPMA, Fiona Knell, Tel: 072 889 2789, Email: fiona. sapma@vadamail.co.za, www.sapma-sa.co.za

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IS YOUR

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THE SOUTH AFRICAN MECHANICAL ENGINEER

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Market Forum Louis Meiring, Zest Group MD says: “As one of the continent’s most prominent suppliers of electric motors, variable speed drives, transformers and switchgear, we have experienced particular growth in West Africa over the past 10 years, primarily by supplying project houses who have secured projects to build mines in the region. We have a massive installed base on mines in the region and decided it was appropriate to establish a dedicated local supply and technical support hub.

A cover plate of a Warman 550 MCR being installed at a copper plant

New pump proves its worth

Weir Minerals’ latest pump, the Warman Mill Circuit (MC) slurry pump, has been successfully trialled at a number of mines in West and Central Africa, in terms of increasing mill throughput capacity and doubling the lifespan of pump wear parts. The pump was first trialled at First Quantum Minerals’ Frontier copper mine in the Democratic Republic of the Congo. The improved performance and longer life expectancy of the pump - due to the increased wear life of the pump’s wet-end parts - resulted in substantial savings on replacement parts.

He adds that until recently it has been heavily dependent on distributors to move its products into countries such as Ghana, Cote D’Ivoire and Mali. Its product spectrum has also expanded beyond electric motors to include products supplied by other group companies and it made absolute sense to set up a fully fledged office in Ghana as a base to service the region with products from all Zest companies.

The Ghana office, established via an investment of R5,5million, is headed up by a country manager, supported by seven permanent staff who manage a robust stockholding housed in warehousing in nearby Tema and provide technical support and training. The company’s SA headquarters has also recently appointed a dedicated African business development manager to focus solely on extending the “phenomenal growth” Louis says Zest is currently enjoying in Africa.

“The Warman 550 MCR slurry pump was installed and commissioned at the Frontier Mine in March 2010, with a mill throughput of up to 1200 tph. In terms of the operational performance of the pump, it achieved a target of 2000 hours of operation without failure; the impeller lasted approximately 2926 hours before requiring replacement; and the rubber liners continued without requiring replacement,” says Rui Gomes, Weir Minerals Africa slurry pumps product manager. The pump has been engineered for arduous operating conditions and manages the large particle sizes of the raw product as well as scats and foreign material so often found in the dense abrasive slurries in a mill discharge application. Weir Minerals Africa, Rene Calitz, Tel: 011 929 2622, Website: www. weirminerals.com Zest Group's offices in Accra, Ghana

Zest sets up shop in Ghana

A vigorous focus on expanding sales beyond South Africa’s borders has seen Zest open a branch in Accra, Ghana, to service the entire West African region.

The company is poised to establish a presence in Zimbabwe as soon as the political situation stabilizes; it is exploring Tanzania as a possible base to provide support and stimulate development of the Group’s infrastructure in Central Africa, and Mozambique is also on its radar. Zest Electric Motors, Jamie Wilson, Tel: 011 723 6000, Website: www. zest.co.za

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Market Forum Enviro friendly waste water filter press New digital torque flange for high torques

Measurement technology specialist HBM’s new T40FM torque flange can measure torques up to 80 kNm without difficulty. The flange has a revised rotor design and new digital rotor and stator electronics, ensuring greater precision and reproducibility in the test benches. The improved measuring body design results in greater stiffness in all directions; simultaneously, it has been possible to reduce the mass, and thus the mass moment of inertia.

Multotec has developed a reportedly world-first environmentally friendly filter press, in response to the increasingly critical need to recycle waste water from mining operations in South Africa, specifically acid mine drainage (AMD). Traditionally hydraulically operated filter presses are used in metallurgical processes and water reclamation plants and associated with a high risk of oil and lubricant contamination during operation. However, the fully automatic filter press, based on the successful Seprotech Rapid Filter press, eliminates the risk of any contamination in this application.

The cloth wash system on the Seprotech Rapid Filter Press features spray bars permanently installed at the top of every plate

The hydraulic power pack has been replaced with a water pressure system which, while achieving the same clamping force, ensures optimum sealing of the plate pack while dramatically reducing noise pollution. The filter cloths have been further developed to ensure longer life, achieving lower consumable consumption; components are designed to ensure safe operation, and finite element analysis has been applied to substantiate the integrity of the machine. The filter press also has energy efficient electric motors. This improved radial stiffness leads to good bending vibration properties and the very high torsional stiffness, in conjunction with the low mass moment of inertia, produces a far better natural torsion frequency. During dynamic measurement, this creates the condition for further expansion of the resonance frequency up to higher values and the entire construction is protected, failures avoided and costs saved. The improved rotor of the T40FM has the same dimensions as predecessor T10FM, ensuring downward compatibility and making it easy to exchange the model in existing applications. Fred Hyde, Tel: 012 8099500, Email: f.hyde@esteq.com

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The filter press can also be used in other liquid/solid separation applications, including copper concentrate, platinum concentrate and coal fines. Multotec Group, Bernadette Wilson, Tel: 011 923 6193, Email:marketing@multotec.co.za, Website: www.multotec.com

Robust spherical roller housed units

Bearing Man Group (BMG), exclusive distributors of QM Bearings throughout Southern Africa, supplies the robust range of QM Blue Brute spherical roller housed units to diverse industries.

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Market Forum “The QMSN series, designed for efficient performance and extended service life in demanding environments, is manufactured with cast steel housings with three times the tensile strength of cast iron housings - an important advantage in applications where there are heavy loads and vibration,” says Rouff Essop, divisional manager, bearings division, BMG. The robustness of the spherical roller housed units means that the bearing can be replaced into the same housing many times, offering substantial cost savings. Three standard sealing options are available. Triple lip nitrile rubber units have a standard sealing arrangement to offer maximum protection for most conditions, including moisture and dirt. It also prevents over packing and the seal’s rubber-covered steel backing plate improves corrosion resistance. Triple lip viton rubber units have the same design as the standard rubber seal, but the viton material improves chemical and temperature resistance. Teflon labyrinth seals consists of a teflon ring that floats between two steel plates and ensures highly efficient sealing. As the material is impervious to most chemicals and because of its low coefficient of friction, these units have a high speed capability. BMG, Rouff Essop, Tel: (031) 576 6200, Fax: (031) 576 6581, Email: rouffe@bmgworld.net, Website: www.bmgworld.net

BET gets new distribution rights

Following its successes with Bellmer presses, Bateman Engineered Technologies (BET) has been awarded distribution rights in South Africa for Bellmer Kufferath Machinery (BKM) products. Bellmer Kufferath designs and produces plant and systems for dewatering, thickening and sorting, its expertise cutting cross a wide range of applications including: thickening and dewatering of sludges and fibres, treatment and dewatering of rejects and dewatering of waste, plastic recycling systems and explosive and/or corrosive media besides others.

Shipment of a Sludge Press with a screw diameter of 1400mm to the UK

“We have had many years of success with Bellmer Winklepress belt presses in Southern Africa in municipal wastewater treatment plants and in the paper and fruit juice industries. We also recently successfully launched a Bellmer Winklepress mobile dewatering plant for sewage and effluent sludge. All this encouraged Bellmer to ask us to distribute its BKM products in this region,” says BET water and effluent manager, Marius Botha. The priority among the BKM product range are screw presses for the dewatering of fibres, sludges and rejects, with several lines of AKUPRESS® screw presses and a wide range of sizes from 200 up to 1,400 mm. Bateman Engineered Technologies, Marius Botha, Tel: (011) 201.2374, Email: marius.botha@bateman-bet.com

Bellmer Kufferath Machinery’s biggest Screw Press with a screw diameter of 1400 mm

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Market Forum New vibration tester delivers smart diagnosis

Comtest Technologies’s new vibration tester, the Fluke 810, enables maintenance teams to rapidly collect data and diagnose and solve mechanical problems. The handheld product is designed and programmed to diagnose the most common mechanical problems of unbalance, looseness, misalignment and bearing failures in a wide variety of mechanical equipment, including motors, fans, blowers, belts and chain drives, gearboxes, couplings, pumps, compressors, closed coupled machines and spindles. When it detects a fault, it identifies the problem and rates its severity on a fourlevel scale to help the maintenance professional prioritise maintenance tasks, and recommends repairs. Context-sensitive on-board help menus provide new users with real-time guidance and tips. It uses a simple step-by-step process to

The three models in the latest 120 cased pump range from Watson-Marlow Bredel SA

repeatable pumping that is easy to validate. With a 2 000:1 speed range (speed accuracy ±1%) and a selection of USP Class VI tubes, the 120 delivers the flexibility and purity vital to drug trials. The biopharm sector includes applications such as fermenter feed, an upstream process important in both production and research, where the growth of cell cultures demands an accurate and repeatable process with no contamination. The pumps are available with single or multi-channel pumpheads and can be used with a variety of tubing materials and sizes to help maximise yield in fermentation and cell culture applications. They are also suitable for single-use systems.

report on machine faults the first time measurements are taken, without prior measurement history. The combination of plain-text diagnoses, severity ratings and repair recommendations helps users make better maintenance decisions and address critical problems first. The Comtest Group, Val Verwer, Tel: 011 608 8520, Email: info@comtest

Ultra-compact and stackable for multiple feeds such as pH control, antifoam, nutrient and buffer addition, the 120 offers a suitable combination of size and technology to optimise the process. The pumps are also effective where the validation of drug research experiments demand accurate flow rate, easy monitoring of parameters and process control. Watson-Marlow Bredel SA, Nico van Schalkwyk, Tel: (011) 796 2960

Fruitful predictive maintenance New pump for the biopharm sector

Watson-Marlow Bredel SA has launched its new 120 cased peristaltic pump range for low-flow applications in the biopharmaceuticals, science and research sectors, suited to single-use systems where no contamination can be accepted. Watson-Marlow Bredel SA general manager Nico van Schalkwyk says biopharm processes require accurate and

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Advanced machine maintenance expert Engineering Dynamics has played a pivotal role in the predictive maintenance and condition monitoring of Amalgamated Beverage Industries’ (ABI) bottling lines at the soft drink manufacturing plant in Phoenix, Kwa-Zulu Natal, for the past three years. ABI’s asset management specialist for the Phoenix plant Anil Mahadeo says Engineering Dynamics reduced unnecessary maintenance activities and costs, while increasing plant VOL 61

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Market Forum productivity, is the use of linear motion devices, which combine otherwise standard components, easily and cost effectively sourced to create specially designed bespoke motion and control systems, states leading global supplier of bearings, seals, mechatronics, lubrication systems and services SKF. These systems offer extremely high performance levels over long, low maintenance operating lives, with the ability to position the heaviest loads with submicron levels of precision and repeatability. This provides opportunities to make considerable improvements in line efficiency, and, as a result, boost profitability.

and equipment life cycles, availability and reliability. This was achieved through the installation and application of vibration monitoring, tribology (oil sampling), balancing, laser alignment and infrared thermography.

With manufacturers such as SKF continuously developing the technology to meet changing market demands, ball screws continue to be a popular choice in many applications for providing a cost effective combination of reliability, accuracy and robustness. The latest ball screws offer particularly high levels of precision and repeatability, with optimised designs to minimise frictional losses, noise and heat, and advanced materials with excellent mechanical characteristics to reduce size and weight, while improving overall performance.

Engineering Dynamics MD and condition monitoring technology specialist Christo van der Walt says that to avoid the overheating of geared motors SKF South Africa, Samantha Joubert, Tel: 011 821 3500, Email: in the bottling lines, infrared samantha.joubert@skf.com, Website: www.skf.co.za camera technology is used to key geared motors along the Engineering Dynamics MD Christo various lines. The infrared van der Walt camera scans and monitors each motor and associated gearbox for an increase in temperature - a key indicator of impending failure. Complex German- and Italian-made machinery used in the plant have numerous moving parts and is therefore enclosed, making data collection by engineers a safety hazard and difficult to reach. Hence, vibration monitoring transducers were installed inside the enclosure on critical motors and gearboxes. Each transducer is wired up to a cable, which is fed outside the enclosure to a junction box where engineers can receive the data. “In the last year, the only failure that the Phoenix plant experienced was on a production line that wasn’t being monitored by Engineering Dynamics,� notes Mahadeo. Engineering Dynamics, Christo van der Walt, Tel: 012 991 3168, Website: www.edprevent.com

Linear motion technology improves productivity

In many applications, the key to achieving success in increasing automation and THE SOUTH AFRICAN MECHANICAL ENGINEER

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Market Forum Drive system reaches new dimensions

Haver & Boecker has introduced the Niagara T-Class screening unit with a newly designed drive system, allowing more amplitude/rotational speed combinations, small cut sizes and difficult classifying jobs with large cut sizes.

increased power consumption and operating costs. For example, in a 100 l/s compressed air system, operating at 7 bar during 6000 hours a year, an additional pressure drop of 150 mbar will increase annual power consumption by approximately 2 000 kW.

The Haver & Boecker team with a Niagara T-ClassR screening machine built at the plant in Muenster, Germany

The machine is also equipped with a newly developed wearprotection system decreasing the replacement time of worn elements, thus reducing downtime. Screening machines with widths starting at 2.40 meters were built in the first phase of development and after the introduction of a time and cost-saving modular construction system, machines with screen decks of almost twice the width (i.e. up to 4.20 m) can now be built at the Münster plant. A recently built 3.5-deck model D180 3000 x 7200 machine of this type was sold to German engineering and plant designer Hazemag in Dülmen. Weighing about 25,000 kg, it separates 450 tons of limestone per hour at 25/15/8 and 4 mm and its dimensions are 3 m x 7.2 m, with the total screening surface amounting to 72 m². Haver Southern Africa, Noel de Wet, Tel: 011 476 4804, Email: n.dewet@haverboecker.co.za

The Atlas Copco filter range is designed to reduce the pressure drop to minimum proportions and delivers numerous benefits: dramatically reduced power consumption, lower maintenance costs and a boost to overall efficiency, productivity and profitability. Atlas Copco South Africa, Philip Herselman, Tel: 011 821 9110, Email: phillip.herselman@ za.atlascopco.com, Website: www.atlascopco.co.za

Don’t Miss Out - Book Now! October 2011 • • •

Contact Louise Taylor on Tel: (011) 781-1401, Fax: (011) 781-1403, Cell: 082 898 3073 or E-mail: editorial@promech.co.za for further details

Filtering out high energy consumption

Swedish multi national, Atlas Copco offers a range of filters which impacts positively on the energy efficiency of a compressor installation. As soon as a filter is fitted, the clogging process starts and the pressure drop gradually increases at a rate dependent on environmental and working conditions. Each 0,5 bar pressure drop draws 3% more energy, with the resulting

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Power transmission - all aspects including gears, couplings, belts, pulleys, chains, etc Computers in engineering - CAD/CAM, design, SCADA, manufacturing systems, ERP, etc Pipes, pumps and valves - couplings, water engineering, maintenance, software aids, etc

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Market Forum High performance

Within Randburg-based Grafo Wiremarker Africa’s newlyacquired Brady product range is high performance indooroutdoor grade vinyl tapes that adhere to pipes (frozen and hot), walls, glass and equipment – most clean, dry surfaces in harsh industrial environments. Used for identification and marking purposes the tapes will stick to irregular, curved or rough surfaces and are tough enough to stand up to grease, oil and most chemicals. An 8 to 10 year outdoor durability average is on par in temperatures from -40ºC to 82ºC, and could last longer if a polyester overlaminate is applied to withstand long term exposure to wind and rain. Available in widths varying from 12.70mm to 50.80mm and in lengths of 15.24mm, the tapes come in a wide range of colour options such as white, yellow, green, red, various blues, orange, grey, black, gold, ochre, pink, tan and clear. Grafo Wiremakers Africa, Darryl Crampton, Tel: 011 704-3295, Email: info@grafo.co.za

New assembly technology division

industry, this generally equates to approximately 12 months; thereby, providing the user with the peace-of-mind that no unnecessary costs will be incurred as a result of downtime.”

Dowson and Dobson Industrial is extending its footprint in its dedicated new assembly technology division, aimed at the higher-end local market. The division will initially host Germanbased Deprag torque shut-off screwdrivers and feeding technology, marketing the range to local automotive sub-suppliers including manufacturers of steering wheel, airbags, mirrors and consoles - before targeting other manufacturers in the long-term. Dowson and Dobson director Terry O’Kelly says the Deprag range meets the highest international specifications for performance and tolerance and is ideallysuited to safety-critical applications.

Dowson and Dobson, Terry O’Kelly, Tel: 011 392 2367, Email: terry.okelly@dowson.co.za Dowson and Dobson national business manager for Assembly Technology, Herman Parsons pictured with Deprag AST 10

Dowson and Dobson national business manager for Assembly Technology, Herman Parsons, notes that the Deprag’s reliability and consistency differentiates it. “For high-spec applications, the torque and tolerance is always specified, and efficiency is measured as a process capability (CP) or process capability index (CPK) value, and a considerable number of cheaper brands are unable to meet these specifications.” Herman says the CPK value required in the automotive sector is 1,67 or better, and the Deprag range is one of only a handful of brands in South Africa capable of meeting these standards. Further, Deprag boasts a preventative maintenance interval of 1-million cycles, which ultimately means that the product might require minor maintenance after the installation of 1-million screws, he continues. “In the automotive THE SOUTH AFRICAN MECHANICAL ENGINEER

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BLACK OR BRIGHT you choose

energy efficiency @ work

Taking energy efficiency light years ahead 16-17 November 2 011, Emperors Palace, Gauteng SAEEC2011EXHIBITORS

An exhibition hall packed with decision-makers, more than at any other event. Exhibition space available at affordable rates. EXHIBITION SPACE (3x3m2) Your exhibit includes: • Standard shell scheme cubicle • Standard company name on fascia • 1 x 15A power point with shared DB • 1 x double fluorescent light • Exhibitor manual for planning, installation, dismantling of booth R11,600 for corporate members (R13,200 non-members)

2x EXHIBITION SPACE (3x3m2) Your exhibit includes: • Standard shell scheme cubicle • Standard company name on fascia • 2 x 15A power point with shared DB • 2 x double fluorescent lights • Exhibitor manual for planning, installation, dismantling of booth R20,400 for corporate members (R23,800 non-members)

SAEEC2011DELEGATES

SAEEC2011SPONSORS

Full delegate: Student delegate: Group discount (5+): SAEE member delegate:

R4,400 R3,300 R4,200 R3,900

Registration fees include entrance to seminar sessions, registration pack, proceedings on CD, daily lunch and refreshments during break.

Enhance your company’s prominence and visibility at this niche event by taking up one of the range of sponsorship opportunities offered.

When booking quote: BW4SAM to qualify for a prize. PRESENTED BY:

For more information contact: Erika Kruger Tel: +27(0)18 290 5130 Cell: +27(0)82 428 7386 Fax: +27(0)86 512 7122 Email: convention@saee.org.za

The Southern African Association for Energy Efficiency (SAEE), chapter of the American Association of Energy Engineers (AEE).

To register and view information about the SAEEC2011 logon to www.saeec2011.org.za.

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Market Forum Reliable mine pumps

Increased service life for motor mounts get

Specialist supplier of electric motors, geared motors, and gearboxes CMG Electric Motors is supplying a range of Vacon AC drives to local industry. “Vacon developed software programmes add value to the range by providing solutions to common problems experienced by industry”, says CMG Product Manager - Drives, Alec Byerley, providing the example of deceleration of motors when “coasting to a stop” and motors are switched off, which causes vibrating screens to shake violently. With repeated starts and stops, the vibrations cause quick deterioration of the rubber or spring mounts and can even cause the motor mounts to crack. With the installation of Vacon’s standard software program, the motors can be decelerated within 1-2 seconds through brake resistors. This eliminates the violent shaking, significantly reducing costly damage to the rubber or spring mounts, increasing service life and reducing maintenance and unwanted down time. Alec adds that the programme also accelerates the motors in 1 – 2 seconds during start-up, further reducing shaking.

The power pumps range of Becker Engineering, exclusive distributors in Southern Africa for Simplex hydraulic and mechanical equipment, includes portable electric and gas powered hydraulic pumps for light and heavy duty maintenance applications on mines.

“These power pumps are available with different pump models, motor selections, valve styles, reservoir sizes, accessories and controls to meet exact requirements,” says Eugene Davids, Simplex product manager for Becker Engineering, part of the Becker Group of Companies. “Simplex 10 000 psi pumps offer a new standard in pump construction and reliability. A close coupled motor and one piece Clydesdale chassis form a rigid unit with minimal flex and wear characteristics, whereas conventional pumps consist of various components bolted together and are more susceptible to internal leakage, overheating and repairs. Becker Engineering, Eugene Davids, Tel: 011 617 6300, Email: info@ za.becker-mining. com, Website: www. za.becker-mining. com

CMG Electric Motors SA, Brian Campbell, Tel: 011 453 1930, Email: brian.campbell@cmggroup.co.za, Website: www.cmggroup.co.za

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Market Forum On the Move

Subscription Please fax us if you wish to subscribe to “SA Mechanical Engineer� at R400,00 (incl postage and VAT) per year; R945,00 per year for Africa/Overseas. We will post you an invoice on receipt of your fax.

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Fax No: (011) 781-1403

From:...................................................................................... (insert your name) Title: ......................................................................................

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Adv Mamokete Ramoshaba

Dr Leon Kruger

Guy Harris has been appointed, as an independent non-executive director, to the board of directors at Booyco Engineering. Mintek is pleased to announce the appointment of three senior managers, Dr Makhapa Makhafola has been appointed general manager: research and development; Adv Mamokete Ramoshaba has been appointed general manager: corporate services; Dr Leon Kruger has been appointed manager: hydrometallurgy division.

Engineer Placements Professional opportunities Our job board continues to display a wide variety of excellent job positions that you can review and apply for on- line. Keep your credentials on our secure and confidential database, update them at any time. We keep in touch with you. www.engineerplacements.com

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Index to Advertisers AST Pyroshield Inside Front Cover Axiom Hydraulics 16 Bonfiglioli 4 Bearings International 24 David Brown 20 Engen 18 Engineer Placements 46 Garnett Cross 14 Hansen Outside Front Cover ILS 26 KSB Pumps Inside Back Cover Monitor Engineering 14 Munters 10 SAEEC 44 SEW Outside Back Cover Sigma Compressors/Renner 33 SKF 30 Zest 27 Voith 19 Weir Minerals 36

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Pumps ƒ Valves ƒ Systems

KSB Slurry Pumps – Ton after Ton Take tons of solids, add liquid and shake vigorously – a recipe for slurry. Whatever the mineral, KSB slurry pumps can finesse the complexity of tar sands and phosphates or transport the glint of gold, copper and metal ores. Beyond mineral processing, KSB’s expertly engineered and robust pumps and valves can also support secondary operations like chemical processing or wastewater pumping. KSB Pumps and Valves (Pty) Ltd www.ksbpumps.co.za

LCC-M Hard metal pumps for general slurries

LCC-R 16 Bar rubber lined pumps for general slurries

LSA-S Premium design design, hard metal pumps for severe slurries

THE SOUTH AFRICAN MECHANICAL ENGINEER

MDX Maximizes up-time up time in SAG, Ball mill circuits and cyclone applications

VOL 61

August 2011

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THE SOUTH AFRICAN MECHANICAL ENGINEER

VOL 61

August 2011


SA Mechanical Engineer August 2011