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hyperMILL 2024 CAD/CAM software suite

OPEN MIND Technologies has introduced its latest hyperMILL 2024 CAD/CAM software suite, which includes a range of powerful enhancements to its core toolpath capabilities, as well as new functionality for increased NC programming efficiency in applications ranging from 2.5D machining to 5-axis milling. New and enhanced capabilities include: Optimized Deep Hole Drilling, a new algorithm for 3- and 5-axis Rest Machining, an enhanced path layout for the 3D Plane Machining cycle, better error detection, and much more.
Learn more.

One-part epoxy changes from red to clear under UV

Master Bond UV15RCL is a low-viscosity, cationic-type UV-curing system with a special color-changing feature. The red material changes to clear once exposed to UV light, indicating that there is UV light access across the adhesive material. Although this change in color from red to clear does not indicate a full cure, it does confirm that the UV light has reached the polymer. This epoxy is an excellent electrical insulator. UV15RCL adheres well to metals, glass, ceramics, and many plastics, including acrylics and polycarbonates.
Learn more.

SPIROL Press-N-Lok™ Pin for plastic housings

The Press-N-Lok™ Pin was designed to permanently retain two plastic components to each other. As the pin is inserted, the plastic backfills into the area around the two opposing barbs, resulting in maximum retention. Assembly time is quicker, and it requires lower assembly equipment costs compared to screws and adhesives -- just Press-N-Lok™!
Learn more about the new Press-N-Lok™ Pin.

Why hybrid bearings are becoming the new industry standard

A combination of steel outer and inner rings with ceramic balls or rollers is giving hybrid bearings unique properties, making them suitable for use in a wide range of modern applications. SKF hybrid bearings make use of silicon nitride (twice as hard as bearing steel) rolling elements and are available as ball bearings, cylindrical roller bearings, and in custom designs. From electric erosion prevention to friction reduction and extended maintenance intervals, learn all about next-gen hybrid bearings.
Read the SKF technical article.

3M and Ansys train engineers on simulating adhesives

Ansys and 3M have created an advanced simulation training program enabling engineers to enhance the design and sustainability of their products when using tapes and adhesives as part of the design. Simulation enables engineers to validate engineering decisions when analyzing advanced polymeric materials -- especially when bonding components made of different materials. Understand the behavior of adhesives under real-world conditions for accurate modeling and design.
Read this informative Ansys blog.

New FATH T-slotted rail components in black from AutomationDirect

Automation-Direct has added a wide assortment of black-colored FATH T-slotted hardware components to match their SureFrame black anodized T-slotted rails, including: cube connectors (2D and 3D) and angle connectors, joining plates of many types, brackets, and pivot joints. Also included are foot consoles, linear bearings in silver and black, cam lever brakes, and L-handle brakes. FATH T-slotted hardware components are easy to install, allow for numerous T-slotted structure configurations, and have a 1-year warranty against defects.
Learn more.

Weird stuff: Moon dust simulant for 3D printing

Crafted from a lunar regolith simulant, Basalt Moon Dust Filamet™ (not a typo) available from The Virtual Foundry closely mirrors the makeup of lunar regolith found in mare regions of the Moon. It enables users with standard fused filament fabrication (FFF) 3D printers to print with unparalleled realism. Try out your ideas before you go for that big space contract, or help your kid get an A on that special science project.
Learn more.

Break the mold with custom injection molding by Rogan

With 90 years of industry experience, Rogan Corporation possesses the expertise to deliver custom injection molding solutions that set businesses apart. As a low-cost, high-volume solution, injection molding is the most widely used plastics manufacturing process. Rogan processes include single-shot, two-shot, overmolding, and assembly. Elevate your parts with secondary operations: drilling and tapping, hot stamping, special finishes, punch press, gluing, painting, and more.
Learn more.

World's first current-carrying fastening technology

PEM^® eConnect™ current-carrying pins from Penn-Engineering provide superior electrical connections in applications that demand high performance from internal components, such as automotive electronics. This first-to-market tech provides repeatable, consistent electrical joints and superior installation unmatched by traditional fastening methods. Features include quick and secure automated installation, no hot spots or poor conductivity, and captivation options that include self-clinching and broaching styles.
Learn more about eConnect pins.

New interactive digital catalog from EXAIR

EXAIR's latest catalog offers readers an incredible source of innovative solutions for common industrial problems like conveying, cooling, cleaning, blowoff, drying, coating, and static buildup. This fully digital and interactive version of Catalog 35 is designed for easy browsing and added accessibility. Customers can view, download, print, and save either the full catalog or specific pages and sections. EXAIR products are designed to conserve compressed air and increase personnel safety in the process. Loaded with useful information.
Check out EXAIR's online catalog.

5 cost-saving design tips for CNC machining

Make sure your parts meet expectations the first time around. Xometry's director of application engineering, Greg Paulsen, presents five expert tips for cutting costs when designing custom CNC machined parts. This video covers corners and radii, designing for deep pockets, thread depths, thin walls, and more. Always excellent info from Paulsen at Xometry.
View the video.

What can you secure with a retaining ring? 20 examples

From the watch dial on your wrist to a wind turbine, no application is too small or too big for a Smalley retaining ring to secure. Light to heavy-duty loads? Carbon steel to exotic materials? No problem. See how retaining rings are used in slip clutches, bike locks, hip replacements, and even the Louvre Pyramid.
See the Smalley design applications.

Load fasteners with integrated RFID

A crane, rope, or chain may be required when something needs lifting -- plus anchoring points on the load. JW Winco offers a wide range of solutions to fasten the load securely, including: lifting eye bolts and rings (with or without rotation), eye rings with ball bearings, threaded lifting pins, shackles, lifting points for welding, and more. Some, such as the GN 581 Safety Swivel Lifting Eye Bolts, even have integrated RFID tags to clearly identify specific lifting points during wear and safety inspections and manage them digitally and without system interruption.
Learn more.

Couplings solve misalignments more precisely with targeted center designs

ALS Couplings from Miki Pulley feature a simplistic, three-piece construction and are available in three different types for more precisely handling parallel, angular, or axial misalignment applications. The key feature of this coupling design is its center element. Each of the three models has a center member that has a unique and durable material and shape. Also called a "spider," the center is designed to address and resolve the type of misalignment targeted. Ideal for unidirectional continuous movement or rapid bidirectional motion.
Learn more.

What is 3D-MID? Molded parts with integrated electronics from HARTING

3D-MID (three-dimensional mechatronic integrated devices) technology combines electronic and mechanical functionalities into a single, 3D component. It replaces the traditional printed circuit board and opens up many new opportunities. It takes injection-molded parts and uses laser-direct structuring to etch areas of conductor structures, which are filled with a copper plating process to create very precise electronic circuits. HARTING, the technology's developer, says it's "Like a PCB, but 3D." Tons of possibilities.
View the video.

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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