FASTENER ENGINEERING - DESIGN WORLD - APRIL 2020

Engineering April 2020

A supplement of Design World

Fastening technology Covering assembly, design, training, welding... plus, what to expect at this year’s Fastener Fair USA!

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Engineering April 2020

A supplement of Design World

Fastening technology Covering assembly, design, training, welding... plus, what to expect at this year’s Fastener Fair USA!

| AdobeStock.com

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Finding strength in community We’re in challenging times. Social distancing has become a way of life. Events and conferences are banned, borders are shut down, and several workplaces have temporarily closed or must work remotely. Companies deemed essential have implemented new safety precautions and limited staff. It’s a struggle that’s impacted nearly everyone worldwide and, at least currently, there’s no obvious end in sight.

One thing that does seem certain, however: the fastener industry will pull through if history is any indication. Although a world health and economic crisis like this is unprecedented in this generation, the majority of companies in the fastener industry are familiar with challenges — and longevity. Take NBK, for example, a specialty manufacturer of mechanical components (including fasteners) with four centuries of experience. The company, which has a U.S. branch, first set up shop in Japan in 1560.

One reason for its staying power: “We’re very much a problem-solving company,” shared Daniel Timm, customer service and inside sales representative with NBK America.

He said the company continually looks for opportunities to provide for and support customers, even it means developing new products.

At Fastener Engineering, we’ve been compiling company profiles and what’s stood out is the remarkable commitment this industry has for its customers and colleagues. While NBK’s history is unique, the majority of fastener companies have decades of experience and wisdom.

Take Patrick Murphy, for example, VP of D.L.P. Coatings, Inc., a provider of painted fasteners. His father started the company in the 80s. The top lesson Murphy learned from his dad: “Treat others how you want to be treated,” he told us. “It’s simple but true.”

Rosa Hearn, an industry veteran with more than 25 years of experience and current product manager for the Proferred Rivets line at Brighton-Best International, also believes kindness is key. She supports the fastener industry and her local community in several ways. She’s the chairman of the Fastener Industry Coalition and WIFI, or Women in the Fastener Industry. These are two organizations dedicated to providing resources and education to those in the industry (such support organizations are yet another reason the sector will manage these tough times).

“It’s important to me to connect with others and share my career experiences, so others are aware of what’s possible,” said Hearn. She’s also on the advisory committee for an economic and workforce development program in California, where she teaches high school and college students about the fastener market.

These company profiles, and others, are posted at fastenerenergineering.com and included in our e-newsletters (simply sign up on our website). If you’d like to share your company’s story with us, please email fasteners@wtwhmedia.com.

We encourage you to continue supporting one another, even from a distance. There is strength in community.

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Mark your calendars:

This year’s Fastener Fair USA includes all industry segments

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North America’s fastest-growing expo for the fastener industry, Fastener Fair USA, will host its third-annual trade show and conference at the Charlotte Convention Center in North Carolina. The event is now set for July 13 to 15, 2020.

“We look forward to getting back to business and reconnecting the industry in Charlotte in July,” said Randy Field, group VP with Reed Exhibitions. The Fastener Fair was originally scheduled for May and postponed due to COVID-19.

“Our number one priority is the health and safety of our exhibitors, attendees, industry partners, and staff,” said Field.

This year’s event theme, “Holding Industry Together,” is a direct reflection of Fastener Fair USA’s mission to serve all industry segments relating to fasteners and fixings.

This includes fastener manufacturing, master distributors,

This year’s theme for Fastener Fair USA is “Holding Industry Together,” which is intended to honor just how important and integral every sector of the fastener industry is today.

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This year’s Fastener Fair includes two days of on-the-floor exhibitions, including Industry Education Stage presentations on July 14 and 15.

equipment makers, tool and software providers, end-users, and more.

“Supply chain, assembly, measurement, and other processes are becoming increasingly integrated into the fastener industry,” shares Bob Chiricosta, event manager for the Fastener Fair USA. “It’s extremely important to us that we offer a comprehensive display of industry innovation with highly relevant education and networking opportunities — all of this in one of the U.S.’ fastest-growing manufacturing regions.”

The pre-show Fastener Fair USA includes an educational pre-show conference program, starting on July 13.

Beginning with an opening keynote, the conference will then segment into three tracks: 1 Fasteners 101, presented by the Fastener Training Institute

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The opening day of the Fastener Fair USA’s Exhibit Hall on July 14 will include an evening welcome party at the NASCAR Hall of Fame from 6:30 to 8:30 p.m.

The Welcome Party tickets cover entry to the NASCAR Hall of Fame with live music, food, and beverages.

Moving fasteners forward The team at Fastener Engineering is proud to partner with Fastener Fair USA as a media sponsor. This year, we’ll be hosting a panel, entitled “How to move fasteners to the front of the design cycle,” which focuses on the importance of considering fasteners earlier on in project planning.

The panel will take place on Tuesday, July 14 from 1:45 to 2:20 p.m. on the show floor. We hope to see you there!

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2 Tom Reilly Training: Value-added Selling, presented by Paul Reilly in partnership with Mid-West Fasteners, a fastener manufacturer and supplier 3 Fasteners in the Smart Factory, presented by Fastener Fair USA As these tracks conclude, registrants with a Monday Conference Pass will have the opportunity to visit a nearby industrial manufacturing plant at Blum, Inc., a family-owned company that operates internationally.

“By including a plant tour with the 2020 Fastener Fair, participants will experience the real-world impacts of the fasteners they produce, add value to, and distribute,” says Chiricosta.

Assured Splice Quality for Assured System Performance When engineered systems rely on the performance of every input and output, every wire and splice counts. That is why, from automatic self-calibration to real-time indication of splice quality, the Branson™ GMX-W1 Ultrasonic Wire Splicer assures repeatability in your assembly operations.

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The main event To set the tone for the event, a 9 a.m. general session that’s titled, “Industry 4.0: Tap the Cloud and Ramp up Profits,” will be presented by Yannick Schilly, president and CEO of Altix Consulting, on July 14.

Attendees can also expect two days of on-theexpo-floor, “Industry Education Stage” presentations on July 14 and 15. This will include more than a dozen panel presentations, with topics such as moving fasteners to the front of the design cycle, sharing ideas for import and export strategies, and understanding smart tools, 3D metal printing, and more.

Additionally, an “Ask the Standards Experts” will take place on both days, starting at 10:15 a.m. with the Fastener Training Institute and Industrial Fasteners Institute, which provides a comprehensive online fastener data resource. Attendees can bring questions about fastening standards to Booth 1237.

“By adding more industry content into the Fastener Fair mix of outstanding networking and business developments, this event will offer everything fastener professionals need to build business,” adds Chiricosta.

Learn more at: Emerson.com/Branson

WHAT DO YOU THINK? Connect and discuss this and other engineering design issues with thousands of professionals online

The Emerson logo is a trademark and a service mark of Emerson Electric Co. © 2020 Emerson Electric Co.

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How offshore manufacturing

has affected local training initiatives John Wachman • Managing Director • Fastener Training Institute Before the 1970s, most fasteners were produced domestically by U.S. manufacturers. Typically, these companies employed field sales executives and engineers to work with distributors and end users on the proper fastener selection and installation. These workers were backed by factorybased product managers and application engineers.

For example, one major supplier had 65 business development executives working throughout the country to support its customer base. Product support was also available for each component type, including bolts, sockets, screws, nuts, washers, and so on.

Eventually, however, the majority of fastener production moved overseas. This was simply a matter of economics, which occurred relatively slowly at first and then the shift accelerated as emerging countries began developing more solid manufacturing facilities. Of course, it was unwise to begin with major aerospace or automobile parts, so smaller components (such as fasteners) provided an ideal manufacturing place to start.

The overseas manufacturing trend continued and, even today, most commodity standard fasteners are imported. Although the U.S. has since revitalized its share of fastener manufacturers, most supply higher quality, engineered fasteners. Certainly, some standard fasteners are produced in America, but suppliers must fight to be competitive. Domestic producers continue to offer great product support, but they are typically lean and product support is limited by economics.

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Over the years, less local manufacturing has led to two challenges: 1 Knowledge drain. Overall, a lack of local experience and knowledge about the entire manufacturing process means there’s a “knowledge drain” in the industry. Compounding this concern are the efficiencies companies have employed over the last three decades to save costs.

For the most part, this has meant doing more with fewer people. As with many companies worldwide, fastener resellers and end users also had to get lean.

2 Tribal knowledge. Several people in the industry are retiring but without an immediate successor

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Students from one of the Fastener Training Institute’s advanced courses. FTI provides training on fastener products, standards, and specifications for students of all levels and experience.

who has been in the industry and gained the experience necessary to properly take over the role.

Now when people retire, those who step into their positions are lucky to have a few years of experience under their belt, never mind 20 or 30 years, which used to be the case.

However, the passing on of tribal knowledge takes time. With a gap in talent, there’s a risk that the tribal or historical knowledge could be lost. The burden on these newly promoted folks to get up to speed is enormous.

Why training matters Given these concerns, how can the industry support smaller producers and their staff with product information and training? The answer is training.

Employees that specify, order, and install fasteners must have a good background in fasteners. The integrity, reliability, and safety of assembled products depend on an educated fastener supply chain. For example, fasteners do experience failures. However,

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The Fastener Training Institute’s (FTI) core purpose is to enhance fastener use, reliability, and safety by providing fastener product and technical training. FTI does so by providing beginning and advanced courses with hands-on training opportunities.

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it’s rarely the result of faulty components and more likely because the wrong fasteners were specified, or they were improperly installed. Proper training aims to prevent such occurrences.

Here’s what to look for in a fastener training program:

• Covers fastener products,

• Ideally, offers beginner and advanced courses

• Hosted by recognized industry experts with years of experience Training that enhances the level of technical understanding and expertise of individuals in the industry is critical for a successful industry.

standards, and specifications

• Teaches proper fastener selection

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and installation methods to prevent unnecessary faults and failures Provides a mix of online and hands-on programs

WHAT DO YOU THINK? Connect and discuss this and other engineering design issues with thousands of professionals online

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How to choose fasteners that maximize assembly life Christie L. Jones • Vice President / Director of Marketing SPIROL International Corporation, U.S.A.

Typically, fasteners are the smallest, least costly components used in an assembly. Perhaps, for this reason, they are rarely considered until the end of a project’s design stage. However, fasteners provide a critical function by holding an entire application together.

Unfortunately, as important as fasteners are, design engineers rarely receive formal training on the mechanics of fastening and joining. This is particularly concerning in certain safety-critical applications, such as with steering columns, brakes, airplane engines, and others.

Adding to the challenge is the sheer volume of fasteners available today.

An assembly can be held together in many ways, using a variety of types of bolts, rivets, screws, pins, and other fastening devices.

Assembly methods fall into two broad categories: 1. Methods that use two components or two operational steps to stay in place 2. Methods where the components are self-retaining

A coiled pin flexes under a load to absorb shock and vibration.

The challenge for the majority of design engineers when selecting a method is cost and reliability. Ideally, the goal is to use the highest quality joint at the lowest manufacturing cost.

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No more loose bolts Nord-Lock created the original wedge-locking technology that secures bolted joints, even when exposed to severe vibration and dynamic loads. It is impossible for our products to loosen unintentionally due to the wedge created underneath the bolt head and nut, thus reducing the risk of production failures or property damage.

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Self-retaining pins For many applications, self-retaining pins provide the ideal solution and assembly method. However, choosing the correct pin for an application requires research.

Technically, when a load is applied, something has to give: the pin, the hole, or an element of the assembly. A pin that’s too rigid typically causes the hole in which it is retained to elongate, eventually leading to assembly failure.

However, a pin that’s too flexible will fatigue under dynamic loading.

There are several types of pins, so choosing pins with the appropriate strength and flexibility for the application is critical. Solid and spring pins are two common types of self-retaining pins.

Solid pins Solid pins come in many different forms, including dowel, knurled, and grooved pins. Generally, solid pins are strong and relatively inflexible.

They’re unable to absorb shock and dynamic loads and, instead, transmit these forces to the mating components. Before choosing solid pins, it’s important to consider these

Coiled spring pins (left) and slotted spring pins (right). dynamic forces for an application.

For example, there’s a common perception that solid pins are ideal for heavy-duty applications. This is typically false because of the pin’s inflexibility. Any force applied to a solid pin is transmitted directly to the hole wall (because it’s unable to flex and absorb the force). This causes the hole diameter to elongate (open up), resulting in reduced retention of the solid pin.

Movement of the pin within the hole can also result from the elongation. In fact, an extremely small change in velocity can result in a large force on the pin (due to F = MV2). This could lead to a pin breaking because of the impact load. Additionally, depending on the severity of the elongation, the distance between the shear planes can widen to the point where the pin is no longer in shear but in bending, which decreases the strength of the pinned joint (and again, the pin may break).

A solid pin’s rigidity elongates the hole, which leads to premature failure of the pinned joint.

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Although using a softer solid pin material might reduce the host damage, it also reduces the pin’s strength. Alternatively, a heat-treated spring pin provides strength and its inherent flexibility can maximize assembly life in dynamic, heavy-duty applications.

Spring pins There are two distinct types of spring pins: slotted and coiled spring pins. Both types share features, including flexibility and an ability to accommodate wider hole tolerances (particularly compared to solid pins).

• Slotted pins offer flexibility during installation, which accommodates wider hole tolerance. In turn, this reduces manufacturing costs.

However, compared to a coiled pin, slotted pins only flex at 180 degrees from the gap. This may lead to premature failure of a pin subject to dynamic loading. If the gap is closed after installation, the slotted pin essentially becomes a hollow inflexible tube.

Then, the same issue occurs under dynamic loading (similar to solid pins), where the pin ends up transmitting the applied load onto the hole wall. This is a concern in applications with a soft host

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Interlocking does not allow for automatic feeding and installation of slotted pins.

material, such as aluminum or plastic.

Additionally, it is extremely difficult to automatically feed and install slotted pins that do not have a controlled gap because they can interlock. The most appropriate applications for these types of pins are non-critical assemblies, manufactured out of mild to hardened steel, that are manually assembled.

• Coiled pins were invented to address many of the disadvantages of using slotted pins. They offer design engineers greater strength and flexibility, including an ability to “customize” the pins balance

of strength and flexibility to the application. For example, light-duty pins are generally recommended for soft or brittle materials, medium (or standard) duty pins are typically used in mild steel and non-ferrous assemblies, and heavy-duty pins are ideal for use in hardened components. They’re also ideal when space limitations prevent the use of a larger diameter standard duty pin.

Coiled pins are capable of absorbing shock and vibration after insertion, which means they provide a prolonged life in most assemblies.

These components are also conducive for automatic feeding and installation. They can fasten multiple components together (such as to pin a gear and shaft) and be used as hinge, alignment, and stop pins.

Typically, coiled pins are not recommended for use as cam followers (a type of roller designed to follow cam lobe profiles), or

where there’s a limited length of engagement for the pin. These applications are generally served best by a solid pin with retention features.

As there are several ways to fasten assemblies, it’s important to take advantage of the application engineering services provided by fastener manufacturers. By partnering with industry experts, design engineers can be assured that their assembly will be equipped with a reliable and cost-effective solution for a safe, long-lasting application.

WHAT DO YOU THINK? Connect and discuss this and other engineering design issues with thousands of professionals online

Under load, stress is concentrated at 180 degrees opposite of the gap in slotted pins.

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Why do bolts loosen?

Julie Pereyra • Sales Engineer • Nord-Lock Group

Depending on the application, bolt loosening can have profound consequences. One loose bolt can bring a whole production plant to a standstill and cost a company thousands. In other applications, loose bolts can pose a significant safety hazard. So, what are the bolt loosening reasons? Broadly speaking, there are two main causes: 1. Spontaneous loosening – shock, vibration, and dynamic load 2. Slackening – settlement, creep, and relaxation “The main causes and consequences of failure depend on the purpose of the bolted joints on the environment and usually on the industry,” says Georg Dinger, Siegenia-Aubi KG, who has extensively studied the causes and effects of self-loosening of bolts.

“For example, the petrochemical industry is primarily concerned with corrosion problems, while fatigue and vibration loosening are usually of minor concern. On the other hand, the automotive industry would probably name self-loosening and corrosion as the sector’s two main problems. The primary concerns for the structural steel industry are joint slip and corrosion, but self-loosening and leakage are less typical. The aerospace industry would probably list fatigue first,” adds Dinger.

Repeated relative displacements between the contact surfaces, which are under the influence of the shank torque and result from the thread pitch torque, can lead to a gradual rotation of the bolt or the nut.

“This causes a bolt preload loss and, consequently, a loss of function in the bolt connection. The effect is well known, but prevention is usually performed experimentally only after the occurrence of self-loosening events,” he says.

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What is preload?

Preload is a term with many meanings in engineering. For example, one is the tension (load) that’s created in a fastener when it’s

An ounce of prevention To prevent spontaneous bolt loosening, the slip between the joined parts needs to be eliminated or at least reduced to below critical levels. This can be achieved by increasing the axial tension or the friction between the clamped parts or decreasing the cyclic loading (for example, shock, vibration, or cyclic thermal loading).

Another common method is to increase the friction between the bolt threads.

Although there are several effective ways to do this, some have disadvantages to consider.

For example, glue or adhesives can be an effective friction-based method but dried glue can be problematic when dissembling and removing a bolt. Furthermore, increasing the friction between threads would decrease the achievable preload at a specific torque level. Locking wire is a common method used in the aviation industry.

Fatigue is permanent damage or deformation in the bolt and clamped parts.

It’s caused by the loss of preload, resulting in an opening in the joint. Spontaneous Bolts are the fastener of choice in multiple industries and applications for the simple reason that they are easy to dismantle. However, this also makes them vulnerable to self-loosening and loss of preload.

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initially tightened. As the bolt stretches, the components between the bolt and the nut compress, thereby increasing the so-called clamp load until the end of the tightening process.

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Las V Company Profile

Washers are an often overlooked component in securing bolted joints. Certain types of washers use tension — rather than friction — to prevent unintended bolt loosening. loosening and slackening are the two basic mechanisms for the loss of preload.

Essentially, spontaneous loosening or rotational self-loosening occurs when a bolt rotates loose because of shock, vibration, or dynamic loads. Even a slight rotation can be enough for a bolted joint to lose all of its preload. This is the most typical cause of bolt loosening.

Slackening is caused by three mechanisms: • Settlement • Creep • Relaxation

“Settlement is critical when it happens due to dynamic loads. It is the permanent deformation of the clamped material when the joint is subjected to the increase of stress from dynamic working loads,” explains Harlen Seow, technical manager with the Nord-Lock Group.

“Most parts of a bolted joint will revert to shape after being released if the stress in the parts have not gone beyond their yield strengths.”

This means some materials in the contact surface, such as paint, will most likely deform permanently,” according to Seow.

Spontaneous loosening or rotational self-loosening occurs when a bolt rotates loose because of shock, vibration, or dynamic loads.

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Understanding why bolts loosen in certain applications is the first step to proper installation.

Creep is a permanent deformation that occurs because of the long-term exposure to high levels of stress below the yield strength of the materials in the joint. It’s more severe in hightemperature applications.

Relaxation is when the microstructure in the materials of a joint restructure, converting existing elastic deformation to plastic deformation over time. Unlike settlement or creep, the clamp length does not change, which makes it more difficult to detect.

“One way to measure preload loss is to measure bolt length after a period in operation and compare it to the bolt length immediately after tightening,” says Seow. “However, this will not detect relaxation, which makes it more problematic.”

The key to avoiding fatigue is a good design, which has grown in importance in recent years because of the increased demands on many bolted joints and greater use of lightweight materials. It’s

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important to avoid solely focusing on the tensile capacity of bolts while overlooking other parameters — such as elasticity and stiffness, which can also be critical.

“Correct joint design is the key to achieving a high-strength friction grip connection with a high preload level, and a high slip resistance over the entire lifetime,” says Dinger. “Up until now, the focus for design engineers has been on the failure with bolts breaking. Other failure mechanisms have become more and more important as performance is increased and the weight of the joints is decreased. The mechanisms of preload relaxation and self-loosening are more common in lightweight designs.”

Depending on the bolt, the application, and the cause of preload loss, there are multiple options for designing more optimal bolted joints.

“In cases where there’s thermal loading, the joint can be optimized by choosing materials with equal thermal expansion coefficient for the clamped parts,” says

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Dinger. “To help minimize settlement and maintain a high preload during operation, you can reduce the roughness between contact surfaces. Measures such as fine hole diameters or toothed surfaces can help minimize relative displacement.”

Overall, achieving the optimal bolted joint involves factoring in multiple variables and design options.

“In general, a good bolted joint is made up of very elastic bolts and stiff clamp parts, and there are different ways of achieving this. One way of improving bolt elastically is to have a long clamp length.

But if you have a flange, where the clamp length can’t be too long, you can change the design by using more but smaller bolts.

So, instead of using five bolts, you can use 10 smaller bolts, which will create a more elastic joint,” says Seow.

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How ultrasonic metal welding technology bonds non-ferrous metals

Joe Stacy • National Sales Manager for Ultrasonic Metal Welding • Emerson Automation Solutions

For nearly 30 years, ultrasonic metal welding has offered manufacturers a uniquely reliable solution for joining a variety of soft, conductive non-ferrous metals ranging from copper, aluminum, and nickel, to lithium, brass, silver, and gold. The process is particularly useful for joining dissimilar combinations of materials in applications that use batteries, power-storage devices, wire harnesses and assemblies, electrical breakers and switches, consumer electronics and cell phones, and implantable medical devices.

Unlike resistance and laser welding, ultrasonic metal welding bonds metals without melting them, so the process never creates intermetallic compounds or particulates, or causes corrosion.

This low-energy, solid-state process bonds metals in several configurations — including thin foils or sheets to stranded wires and bus bars (up to 2 mm in thickness), producing connections with a high electrical conductance for maximum electrical efficiency.

One of the technology’s most important applications involves transportation, where nearly all batteries used in electric vehicles rely on ultrasonic metal welding to join their smallest and most basic components. These include the thin nickel, copper, and alloy films used in anodes and the aluminum foils typically used in cathodes, as well as the anode and cathode tabs that bind their power-generating chemistries together.

A variant of the process, ultrasonic metal splicing, ensures the integrity of wire harnesses and terminations essential to delivering electric power, sensor inputs, or control signals in a host of other applications, worldwide.

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Converting electrical energy into ultrasonic welding energy

Ultrasonic metal welding at work As seen in the Converting electrical energy into ultrasonic welding energy diagram, the power supply takes a standard electrical line voltage (typically 50 or 60 Hz) and converts it to the frequency required for metal welding (40 kHz for smaller or more delicate parts and 20 kHz for larger, thicker parts).

The electrical energy is sent through an RF cable to the converter.

The converter uses piezoelectric ceramics to convert the electrical energy to mechanical oscillations at the operating frequency of the power supply. These oscillations are either increased or decreased, depending on the configuration of the booster and horn. The proper degree of oscillation, known as amplitude, is typically determined by an applications engineer. Precise control of amplitude is essential for repeatable metal welding.

The bonding is accomplished by using high-frequency vibration to the

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Ultrasonic metal splicing metallurgically bonds stranded non-ferrous wires using vibratory motion and pressure.

metals that are held under pressure, and applied by the actuator. The lower metal part is held stationary in a piece of tooling called an anvil, and the upper part is pressed against it while subject to the motion of an oscillating horn or “sonotrode.” The sonotrode extends horizontally from the power supply of the welder and is the source of the ultrasonic energy www.fastenerengineering.com

that creates the metal-to-metal bond.

When the weld process begins, the upper part is oscillated by the horn, producing a shear force that “scrubs” surface oxidation and contaminants away and creates a smooth, metal-to-metal contact.

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Fastening + Joining

Ultrasonic metal welding and splicing: The process benefits • • • • • • • •

Works with a wide range of non-ferrous materials Creates a permanent, metallurgical bond between dissimilar metals Requires no melting — there’s zero change to the chemistry or metallurgy of materials Joins highly conductive alloys — the reactivity of materials doesn’t matter Creates no intermetallic compounds, particulates, or corrosion-causing reactions Bonds thin, fragile metal films and structures Offers multiple methods of control, enabling process customization, repeatability, and SPC Provides a low-energy input (up to 30 times lower energy use than with fusion or resistance welding), and without consumables

•

Offers the lowest total cost per weld of any welding technology

mingle at their interface — and bond at the molecular level. The result is a continuous weld with a finely grained structure similar to the structure of cold-worked metals.

The entire process is very rapid, with welds typically completed in a fraction of a second.

Multiple methods for control In addition to its ability to bond non-ferrous metals without melting or damaging them, ultrasonic metal welding offers multiple methods of control, which can meet several production challenges.

Ultrasonic welding can join 100 layers or more of thin copper or aluminum foils, simplifying the assembly of power-dense, multi-layer battery designs used in the newest electric vehicles.

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Among the most important of these control modes are:

• Weld energy control, which allows welding for a fixed length of time (time mode), to a particular finished weld height (height mode), or to a fixed level of energy input (energy mode). In energy mode, the ultrasonic metal welder automatically compensates, varying the duration of the weld to adapt to commonly occurring differences in the surface conditions (e.g. the degree of oxidation and contamination) of the metals being joined. www.fastenerengineering.com

• Weld amplitude control, which regulates the length of oscillation (amplitude) delivered to the weld zone of each joint, and uses the capabilities of the weld power supply, converter, and sonotrode and horn assembly.

• Weld downforce control regulates the pressure applied to the joint being welded. Advances in automation for downforce control cut both ways, enabling the application of greater and lesser pressure to be applied with exceptional precision.

One example is Branson GSX, an ultrasonic welder from Emerson that incorporates a new “featherlight” electromechanical actuation system, which measures downforce so precisely that it can repeatably initiate ultrasonic welding with a fraction of the downforce required by older equipment.

Another new ultrasonic welding technique developed in Emerson’s Application Laboratory uses higher actuation pressure on stacked metal films so that a durable weld can be created more “gently,” using less total weld amplitude.

DESIGN WORLD

4/13/20 4:16 PM

FOR

THE INDUSTRY, IN THE OF MANUFACTURING

After extensive internal and external consultation and monitoring of the COVID-19 pandemic, we have made the decision to postpone Fastener Fair USA to July 13-15, 2020 at the Charlotte Convention Center.

Fastener Fair USA is the only exhibition in the U.S. dedicated to the full supply chain–distributors, mechanical and design engineers, purchasers, wholesalers, and End -Users/OEMS—spanning key vertical industries. The third annual Fastener Fair USA will be held in Charlotte, NC, putting the show in one of the biggest manufacturing hubs in North America. Visitors can expect a comprehensive display of industry innovation with highly relevant education and unmatched opportunities to connect with peers and industry experts.

NEW DATES ANNOUNCED!

JULY

13-15 2020

CHARLOTTE CONVENTION CENTER CHARLOTTE, NC

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4/9/20 4:22 PM

FASTENER FASTENER 138

Selecting the Optimal Washer Flat: Generally used for load disbursement Tab/Lock: Designed to effectively lock an assembly into place Finishing: Often found on consumer products Wave: For obtaining loads when the load is static or the working range is small Belleville: Delivers the highest load capacity of all the spring washers Fender: Distributes a load evenly across a large surface area Shim Stacks: Ideal for simple AND complex applications

Boker’s Inc. 3104 Snelling Avenue Minneapolis, MN 55406-1937 Phone: 612-729-9365 TOLL-FREE: 800-927-4377 (in the US & Canada)

bokers.com

Branson GMX-W1 Ultrasonic Wire Splicer from Emerson Blends Performance, Ergonomics The Branson GMX-W1 Ultrasonic Wire Splicer from Emerson delivers precise and repeatable splicing of non-ferrous wires for in-line or pig-tail configurations. The lightweight, compact design of the GMX-W1 splicer makes it ideal for use as a portable unit for wire harness in-line assembly boards.

The user-friendly design of the GMX-W1 splicer features a 22” touchscreen HMI, whose touch-keyboard and drag-and-drop program editor make it simple to create, edit, and recall different production recipes for splices, sequences, and harnesses. The screen also accesses the unit’s multiple welding control modes and offers flexibility for configuring production- and quality- monitoring solutions. The actuator unit of the GMX-W1 splicer is also userfriendly with an illuminated weld area, and a patented vertical stacking feature in the welding head.

Emerson Automation Solutions www.Emerson.com/Branson

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www.fastenerengineering.com

DESIGN WORLD

4/9/20 5:31 PM

FASTENER FASTENER

HUNTING FOR THE RIGHT ADHESIVE FOR YOUR PROJECT? GLUESPEC HAS A KILLER SELECTION OF BONDING, JOINING & FASTENING MATERIALS Join the thousands of engineers already using Gluespec

WWW.GLUESPEC.COM

No More Loose Bolts with Nord-Lock Washers Nord-Lock created the original wedge-locking technology to secure bolted joints with tension instead of friction. The system is composed of a pair of lock washers with cams on one side and radial teeth on the other.

Nord-Lock washers secure the fastener in a joint that cannot be loosened even when subjected to extreme vibration or dynamic loads. Our range includes steel construction washers, wheel nuts, combi bolt washers and custom solutions.

Features: • Available for bolt sizes M3 - M130 • Available in 5 different materials - steel, stainless steel, 254 SMO®, INCONEL® / HASTELLOY® and C-276 INCONEL® 718 • Available with enlarged outer diameter (SP washers) • Reliable bolt securing system at high and low clamp loads

DESIGN WORLD

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Nord-Lock Group www.nord-lock.com 412-279-1149

www.fastenerengineering.com

April 2020

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FASTENER

Pivot Point, Inc. The SLIC Pin™ from Pivot Point is a pin and cotter all-in-one. An excellent alternative to installing e-clips and secondary cotters, the patented SLIC Pin features a spring-loaded plunger which acts as an automatic cotter pin. SLIC installs faster and more consistently than two-piece combinations – increasing productivity, cutting labor costs, and reducing risk of mis-installation and accidental disengagement.

Simply depress the plunger with your finger or a tool in order to remove the pin. Use our “removable” style plunger if removing through small gaps. SLIC Pins can be made in virtually any material and finish. Millions of SLIC Pins are installed every year across all industries. Contact Pivot Point for free samples and information.

Pivot Point, Inc. www.pivotpins.com PO Box 488 Hustisford, WI 53034 761 Industrial Lane Hustisford, WI 53034 800-222-2231

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www.fastenerengineering.com

DESIGN WORLD

4/10/20 2:15 PM