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Standard parts with signal feedback included

JW Winco standard parts are becoming even more functional -- multifunctional, to be precise. From smart stop bolts that report whether workpieces are precisely positioned in the machining process to cabinet handles with signal lights and fluid level indicators with electronic REED contact signals, intelligent standard parts from JW Winco ensure greater safety, higher efficiency, and increased stability. Many more very useful options available for a wide range of applications.
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Particle foam perfectly distributed thanks to simulation with Ultrasim

BASF's Ultrasim simulation solution now includes Infinergy, an expanded thermoplastic polyurethane (E-TPU) that is used in a wide range of applications to make components with particle foam -- from bicycle tires to the soles on shoes. Identify and solve problems related to pneumatic filling when distributing particle foams in molds, even taking gravity and mold closing into consideration. Avoid those pesky air pockets.
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Best practices for making technical drawings

Ambiguities in technical drawings can cost extra money when a part must be redone or reworked, leading to unexpected project delays. It is essential to create clear technical drawings the first time around. Did you remember to include an isometric view if possible? Did you limit the number of hidden lines? Xometry lays out 14 tips that to help engineers create clear and professional manufacturing drawings. A solid review.
Read the full Xometry article.

NEW! Semi-automatic pin installation technology from SPIROL -- Better, faster fastening

SPIROL's new video showcases their updated Model PR and Model CR Semi-Automatic Installation Machines for Pins, Alignment Dowels, and Bushings. The video demonstrates how to operate the machine, details standard features, and optional quality and error-proofing enhancements. More than 80% of the components in this installation equipment are standard, pretested, production-proven, off-the-shelf parts. This translates into faster delivery, greater reliability, and lowest cost for equipment of comparable quality.
View the video.

Are fasteners over-torqued in your assemblies?

According to Mountz, if you currently use a click wrench for your bolting application, you should proceed cautiously because click wrenches are easily misused, which leads to over-torque events. Replacing a click-wrench with a Mountz FGC cam-over wrench helps prevent operator anomalies and over-torque occurrences, because a cam-over mechanism physically prevents the operator from over-torquing fasteners.
Learn more.

Tools for robotic metal weld grinding

There are many ways to automate grinding processes, but according to ATI Industrial Automation, "Compliance is the key to successful robotic grinding applications." Learn about the pneumatic compliance built into ATI's tools -- the CGV Compliant Angle Grinder and the PCFC Passive Compliant Force Control device -- that exerts a constant force and compensates for surface irregularities to ensure consistent results and facilitate easier robot programming.
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How BMW Group uses ExOne binder jetting tech to make parts

3D-printer maker ExOne and BMW have worked together for more than two decades on additive manufacturing projects. This video showcases how the premium automaker uses ExOne binder jet sand 3D-printing technology to manufacture water jacket cores in serial production. Binder jetting is one of the fastest 3D-printing methods for producing high-quality and complex precision parts in high volume.
View the video.

NEW: Build parts together with Teamspace from Xometry

Xometry's Digital Manufacturing Marketplace has just launched Teamspace, a new product feature that makes it easy for you and your team to build big ideas together. Teamspace is a collaborative workspace within your Xometry account that gives you and members of your team quick and easy access to quotes, order placement, part status, tracking info, and more. Turbocharge the way you make custom parts using additive manufacturing, CNC machining, sheet and tube fabrication, plastics, metals, and more.
Learn more.

Clean in Place Latches save time and money

Spend less time and money on cleaning and cleaning media with two new standard parts from JW Winco. The new GN 1150 latches are designed to repel dirt and can be cleaned in place. The Hygienic Design latches support the machine and system cleaning concept known as clean in place, or CIP for short. Two versions available: front hygiene (FH) for applications such as switch cabinets that must comply with hygiene requirements only on the outside, and full hygiene (VH) with additional seals for HD quality, even on the latch arm side.
Learn more.

Flex Locators for quick changeover of small and large fixtures

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!
View the video.

Injection-molded heavy-duty plain bearings for high mechanical loads

igus has introduced a new two-component plain bearing for high mechanical loads called the iglide Q3E series. With this new, greaseless offering, igus has, for the first time, found a way to manufacture heavy-duty bearings made of two layers of high-performance plastic using the cost-effective injection molding process. Applications include the construction and agricultural machinery industries.
Learn more.

Premium polymer DLP printer is half the price of its predecessor

Desktop Metal has just launched the ETEC Pro XL -- a premium polymer digital light processing (DLP) printer that enters the market at less than half the price as its predecessor. DLP is regarded by many as a superior polymer 3D-printing technology for speed, surface finish, and accuracy. Ideal for automotive and machine parts, aerospace components, housings, connectors, jigs and fixtures, short-run molds, and more.
Read the full article.

Photo etching ramps up heat exchanger design

Photo-chemical etching is a powerful technique for manufacturing heat exchangers that offers numerous advantages over traditional methods and addresses key challenges -- all while paving the way for innovative designs in various industrial applications from power generation and automotive systems to HVAC systems and aerospace technology.
Read the full article.

Replace traditional fasteners: Retaining ring applications

Using a Rotor Clip Retaining Ring to fasten your assembly instead of a traditional fastener not only reduces your costs, but it also saves the environment. Fewer parts and less material means cost savings for you and less waste for the planet. This quality part offers lot traceability. Want to know what you can do with a Rotor Clip Retaining Ring?
View application examples.

New EXAIR catalog: Solutions for manufacturing problems

EXAIR's new Catalog 35 is a full-color technical guide offering innovative solutions to common industrial conveying, cooling, cleaning, blowoff, drying, coating, and static electricity problems. The expanded Catalog 35 features new products, guides, research, certifications, and many other helpful tools to assist customers in getting the most out of their manufacturing processes.
Get your EXAIR Catalog 35.

New surface treatment could improve refrigeration efficiency

Specialized thin coatings developed by the MIT team cause even low-surface-tension fluids to readily form droplets on the surface of a pipe, as seen here, which improves the efficiency of heat transfer. [Image courtesy: MIT researchers]

 

 

 

 

By David L. Chandler, MIT

Unlike water, liquid refrigerants and other fluids that have a low surface tension tend to spread quickly into a sheet when they come into contact with a surface. But for many industrial processes, it would be better if the fluids formed droplets, which could roll or fall off the surface and carry heat away with them.

Now, researchers at MIT have made significant progress in promoting droplet formation and shedding in such fluids. This approach could lead to efficiency improvements in many large-scale industrial processes including refrigeration, thus saving energy and reducing greenhouse gas emissions.

The new findings are described in the journal Joule, in a paper by recent graduate and postdoc Karim Khalil PhD '18, professor of mechanical engineering Kripa Varanasi, professor of chemical engineering and Associate Provost Karen Gleason, and four others.

Over the years, Varanasi and his collaborators have made great progress in improving the efficiency of condensation systems that use water, such as the cooling systems used for fossil-fuel or nuclear power generation. But other kinds of fluids -- such as those used in refrigeration systems, liquification, waste heat recovery, and distillation plants, or materials such as methane in oil and gas liquifaction plants -- often have very low surface tension compared to water, meaning that it is very hard to get them to form droplets on a surface. Instead, they tend to spread out in a sheet, a property known as wetting.

But when these sheets of liquid coat a surface, they provide an insulating layer that inhibits heat transfer, and easy heat transfer is crucial to making these processes work efficiently. "If it forms a film, it becomes a barrier to heat transfer," Varanasi says. But that heat transfer is enhanced when the liquid quickly forms droplets, which then coalesce and grow and fall away under the force of gravity. Getting low-surface-tension liquids to form droplets and shed them easily has been a serious challenge.

In condensing systems that use water, the overall efficiency of the process can be around 40 percent, but with low-surface-tension fluids, the efficiency can be limited to about 20 percent. Because these processes are so widespread in industry, even a tiny improvement in that efficiency could lead to dramatic savings in fuel, and therefore in greenhouse gas emissions, Varanasi says.

By promoting droplet formation, he says, it's possible to achieve a four- to eightfold improvement in heat transfer. Because the condensation is just one part of a complex cycle, that translates into an overall efficiency improvement of about 2 percent. That may not sound like much, but in these huge industrial processes even a fraction of a percent improvement is considered a major achievement with great potential impact. "In this field, you're fighting for tenths of a percent," Khalil says.

Unlike the surface treatments Varanasi and his team have developed for other kinds of fluids, which rely on a liquid material held in place by a surface texture, in this case they were able to accomplish the fluid-repelling effect using a very thin solid coating -- less than a micron thick (one-millionth of a meter). That thinness is important to ensure that the coating itself doesn't contribute to blocking heat transfer, Khalil explains.

The coating, made of a specially formulated polymer, is deposited on the surface using a process called initiated chemical vapor deposition (iCVD), in which the coating material is vaporized and grafts onto the surface to be treated, such as a metal pipe, to form a thin coating. This process was developed at MIT by Gleason and is now widely used.

The authors optimized the iCVD process by tuning the grafting of coating molecules onto the surface, in order to minimize the pinning of condensing droplets and facilitate their easy shedding. The process could be carried out on location in industrial-scale equipment, and could be retrofitted into existing installations to provide a boost in efficiency. The process is "materials agnostic," Khalil says, and can be applied on either flat surfaces or tubing made of stainless steel, titanium, or other metals commonly used in condensation heat-transfer processes that involve these low-surface-tension fluids. "Whatever materials are used in your facility's heat exchanger, it tends to be scalable with this process," he adds.

Video shows the condensation of pentane, a low-surface-tension fluid. On the left, streaking of drops impairs heat transfer, while pentane with the new coating, at right, shows high droplet formation and good heat transfer.

The net result is that on these surfaces, condensing fluids like the hydrocarbons pentane or liquid methane, or alcohols like ethanol, will readily form small droplets that quickly fall off the surface, making room for more to form, and in the process shedding heat from the metal to the droplets that fall away.

One area where such coatings could play a useful role, Varanasi says, is in organic Rankine cycle systems, which are widely used for generating power from waste heat in a variety of industrial processes. "These are inherently inefficient systems," he says, "but this could make them more efficient."

The new coating is shown promoting condensation on a titanium surface, a material widely used in industrial heat exchangers.

"This new approach to condensation is significant because it promotes drop formation (rather than film formation) even for low-surface-tension fluids, which significantly improves the heat transfer efficiency," says Jonathan Boreyko, an assistant professor of mechanical engineering at Virginia Tech, who was not connected to this research. While the iCVD process itself is not new, he says, "showing here that it can be used even for the condensation of low-surface-tension fluids is of significant practical importance, as many real-life phase-change systems do not use water."

Saying the work is "of very high quality," Boreyko adds that "simply showing for the first time that a thin, durable, and dry coating can promote the dropwise condensation of low-surface-tension fluids is very important for a wide variety of practical condenser systems."

The research was supported by the Shell-MIT Energy Initiative partnership. The team included former MIT graduate students Taylor Farnham and Adam Paxson, and former postdocs Dan Soto and Asli Ugur Katmis.

Published May 2019

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