June 04, 2024 Volume 20 Issue 21

Mechanical News & Products

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Build-to-order knobs and hand hardware

Rogan Corp.'s innovative use of two-shot plastic injection and insert molding has been providing customers with high-quality plastic clamping knobs, levers, and control knobs for almost 90 years. Rogan offers concurrent engineering, product design, and assistance in material selection to ensure customer satisfaction for standard or customized parts, with a focus on cost optimization and on-time delivery. Custom colors, markings, decorative inlays, or engineered materials to meet special requirements, such as adding extra strength or utilizing flame-retardant material, are all offered.
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Slewing ring bearing made of wood and plastic

The PRT-02-30-WPC slewing ring bearing is another step forward by igus toward integrating renewable raw materials into industrial production. Made of 50% wood and 50% high-performance plastics, the cost-effective and lubrication-free slewing ring bearing balances strength and durability with a proven low CO2 footprint. The materials incorporate solid lubricants, making the new slewing ring bearing smooth running and maintenance-free.
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Flex Locators for quick fixture changeover

Flex Locators from Fixtureworks are designed for quick changeover of small and large fixtures, automation components, and more. They are ideal for applications that require frequent disassembly, providing excellent repeatability for locating and clamping in a single operation. Manual and pneumatic versions are available. Just turn the handle, knob, or screw!
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Copper foam -- so many advantages

Copper foam from Goodfellow combines the outstanding thermal conductivity of copper with the structural benefits of a metal foam. These features are of particular interest to design engineers working in the fields of medical products and devices, defense systems and manned flight, power generation, and the manufacture of semiconductor devices. This product has a true skeletal structure with no voids, inclusions, or entrapments. A perennial favorite of Designfax readers.
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New torque inserts provide design flexibility

Reell's TI-330 torque insert completes the gap in torque range between the TI-320 and TI-340 models in the TI-300 series, providing enhanced design flexibility for a wider range of applications. With torque options ranging from 1.0 to 2.5 Nm, the TI-330 features a powdered metal package configuration designed to be press-fit into round holes for quick and easy installation. Mounting profile options include exposed knurled shaft end and a knurled zinc adapter for installation into plastics.
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Superior fastening solution for securing rotating components to a shaft

SDP/SI Shaftloc® fasteners offer distinct advantages over other fastening methods when securing rotating components to a shaft. The key to this compact, efficient design is its asymmetric thread geometry that produces a greater clamping force -- outperforming other fastening methods. Shaftloc is a patented fastening system manufactured by SDP/SI.
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Great design: Handle with integrated lighting/signaling

Signaling and indicator lights, switches, and buttons -- elements that hardly any machine can do without. The new JW Winco cabinet U-handle EN 6284 integrates all these functions into a single, compact element. The new U-handle is designed to enhance the operation of systems and machines. It features an integrated button and a large, colored, backlit area on the back of the handle. These elements can be used individually or in combination, providing a versatile tool for system control and process monitoring that can be seen from across the room.
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SOLIDWORKS: FeatureManager tips for assemblies

Discover tools to make your SOLIDWORKS assembly Feature-Manager design tree display easier to view and use. Learn options to limit the amount of information in each component listing, combine multiple instances of a component into a single listing, and separate fasteners mates into a new folder. Lots more tips on the SOLIDWORKS YouTube channel.
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Top die casting design tips: Xometry

Optimize your die casting project's manufac-turability with these 23 top design tips from Xometry. Ensure your work is cost effective too, so you can hit the ground running and have the highest chance of success. Tips include: fillets and radii, wall thicknesses, ribs and metal savers, holes and windows, parting lines, finishes, and more.
Read the Xometry article.

8 top ways to wreck your coupling-driven system

Engineers at Ruland Manufacturing Co. have compiled the eight best ways to consistently sabotage or damage your coupling-driven system -- and how to avoid these pitfalls in the future. Misunderstanding performance criteria such as misalignment, torque, or rpm can be all it takes to cause a critical and costly failure.
Read the full article.

New washer tech for leak-free automotive sealing

Trelleborg Sealing Solutions has just launched the Rubore® Washer, a unique solution offering virtually leak-free sealing beneath screwheads to safeguard critical systems in vehicles, especially electric ones.
Read the full article.

How Reell electric wrap spring clutches work

Electric wrap spring clutches are ideally suited for critical timing applications requiring consistent, repeatable engagement and disengagement performance. Wrap spring technology used in Reell clutches provides the capability to transmit a large amount of torque in a small size -- package sizes smaller than other clutch technologies such as friction disk, tooth, or magnetic particle. Reell's technology has very positive engagement characteristics and also limits the effects of wear.
Read this informative Reell article.

New 'breathable' rupture disk tech provides overpressure and vacuum relief

To increase equipment safety and reliability, a new rupture disk technology activates at a set burst pressure, but it can also "breathe" to relieve minor pressure fluctuations. The patent-pending, dual-function device from BS&B Safety Systems is ideal for use on low-pressure vessels that are susceptible to ambient temperature changes.
Read the full article.

Engineer's Toolbox: 9 considerations for specifying a slewing ring bearing

In applications that require a bearing to support a structure while it rotates (e.g., cranes, radar, tank turrets), premature bearing failure can put people and equipment at risk. While slewing ring bearings have proven themselves countless times in such applications, designers must consider many factors when specifying them. According to engineers at Kaydon, the bearing's support structure, mounting (including bolt strength, tensioning, and hole patterns), installation, and even storage are all factors in a bearing's success or failure.
Read the full article.

ClampDisk micro fastener is new alternative for automotive and consumer electronics

Designed as a unique alternative in assemblies for the automotive and consumer electronics markets, the ClampDisk Press-on Fastener is a new offering from PennEngineering that delivers a fast, simple way to achieve sheet-to-sheet clamped fastening while replacing the use of standard screws, nuts, and adhesives. The most common challenges that can be eliminated or reduced by using ClampDisk include over installation, cross threading, stripped screw heads, broken screws, and damaged product. This fastener can be removed easily with a sharp-edged tool.
Learn more and see how ClampDisk works.

Modified stainless steel kills bacteria without antibiotics or chemicals

Researchers etch nano-sized textures and add copper ions to create a naturally antibacterial material for hospitals and other shared settings.

By Joshua Stewart, Georgia Tech University

An electrochemical process developed at Georgia Tech could offer new protection against bacterial infections without contributing to growing antibiotic resistance.

The approach capitalizes on the natural antibacterial properties of copper and creates incredibly small needle-like structures on the surface of stainless steel to kill harmful bacteria like E. coli and Staphylococcus. It's convenient and inexpensive, and it could reduce the need for chemicals and antibiotics in hospitals, kitchens, and other settings where surface contamination can lead to serious illness.

It also could save lives: A global study of drug-resistant infections found they directly killed 1.27 million people in 2019 and contributed to nearly 5 million other deaths -- making these infections one of the leading causes of death for every age group.

Postdoctoral scholar Anuja Tripathi examines a small sample of stainless steel after an electrochemical etching process she designed to create nano-scale needle-like structures on its surface. A second process deposits copper ions on the surface to create a dual antibacterial material. [Credit: Photo by Candler Hobbs, Georgia Tech]





Researchers described the copper-stainless steel and its effectiveness May 20 in the journal Small.

"Killing Gram-positive bacteria without chemicals is comparatively easy, but tackling Gram-negative bacteria poses a significant challenge, due to their thick, multilayered cell membrane. And if these bacteria persist on surfaces, they can grow rapidly," said Anuja Tripathi, the study's lead author and a postdoctoral scholar in the School of Chemical and Biomolecular Engineering. "I aimed to develop an antibiotic-free bactericidal surface effective against Gram-negative and Gram-positive bacteria."

Tripathi and her colleagues -- William R. McLain Professor Julie Champion and former Ph.D. students Jaeyoung Park and Thomas Pho -- produced a one-two punch that overcomes those challenges and doesn't help bacteria develop resistance to drugs.

The team first developed an electrochemical method to etch the surface of stainless steel, creating nano-sized, needle-like structures on the surface that can puncture bacteria's cell membranes. Then, with a second electrochemical process, the researchers deposited copper ions on the steel's surface.

The different stages of Tripathi's process: At top, an unmodified sample and at bottom a sample after the electrochemical etching process. [Credit: Photo by Candler Hobbs, Georgia Tech]





The different stages of Tripathi's process: Two samples after copper ion deposition -- four minutes for the top piece and 15 minutes for the bottom piece. [Credit: Photo by Candler Hobbs, Georgia Tech]





Copper interacts with the cell membranes and ultimately compromises them.

"The nanotextured stainless steel can kill both Gram-negative and Gram-positive bacteria, but we wanted to enhance the antibacterial activity for surfaces that can be highly contaminated," Tripathi said. "The copper coating on the nanotextured stainless steel gave us very high antibacterial activity."

Despite copper's known antibacterial properties, it's not widely used to fight surface contamination because it's expensive. Tripathi's approach deposits only a thin layer of copper ions on the stainless steel, so it's cost effective without compromising the material's antibacterial activity.

Together, the dual attacks resulted in 97% reduction of Gram-negative E. coli and 99% reduction in Gram-positive Staphylococcus epidermis bacteria in the group's study.

Tripathi said the stainless steel could be used for common tools in medical settings that are easily fouled, such as scissors or tweezers. It could be used for door handles, stair railings, and perhaps even sinks -- places where stainless steel is often the material of choice and surface bacteria are common, especially in hospitals or other shared settings.

The process she and her colleagues developed also could be useful in food service. Tripathi said the approach could be fairly easily incorporated into existing industrial processes, where different electrochemical coating methods already are used for stainless steel food storage containers.

Atomic force microscope images show a stainless steel sample before electrochemical etching (top) and after the process (bottom). Tripathi's process creates needle-like protrusions at the nanometer scale that are capable of killing bacteria cells. [Credit: Images Courtesy Anuja Tripathi, Georgia Tech]





Tripathi said future work will investigate if the copper-coated, nanotextured stainless steel is effective against other kinds of cells harmful to human health. She's also interested in exploring whether the steel could be used for medical implants to help ward off infections.

Since it proved effective against troublesome E. coli, she's hopeful.

"Reflecting on a recent E. coli outbreak in grocery stores in Calgary, Canada, I was particularly driven in my research, recognizing the urgent relevance and significance of combating such resilient bacteria on surfaces," Tripathi said. "They can be difficult to eliminate. So, if we can effectively eliminate E. coli, we stand a good chance of eradicating many bacteria on surfaces."

Published June 2024

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