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New Standard Parts Handbook from JW Winco

JW Winco's printed Standard Parts Handbook is a comprehensive 2,184-page reference that supports designers and engineers with the largest selection of standard parts categorized into three main groups: operating, clamping, and machine parts. More than 75,000 standard parts can be found in this valuable resource, including toggle clamps, shaft collars, concealed multiple-joint hinges, and hygienically designed components.
Get your Standard Parts Handbook today.

PBC linear shafts, bearings, and shaft supports from AutomationDirect

Automation-Direct has added PBC linear shafts, bearings, and shaft supports to their power transmission product category. PBC linear shafts are precision ground to provide an optimized surface for plain and ball bearings and are ideal for high-precision linear motion applications where tight tolerances are needed. Shafts are available in carbon or stainless steel with round and fully supported models in diameters from 1/4" to 1-1/4" and lengths from 6" to 36". Maintenance-free plain bearings or ball bearings available.
Learn more.

Great Resources: ABCs of gears and more

KHK USA takes you on a journey through the history and applications of gears in two information-packed, no-cost volumes called "The ABCs of Gears." Part A is aimed at beginners, while part B moves on to intermediate fare, such as types of gears and tooth forms, heat treatment, surface treatment, production methods, etc. Another mid-level text called "Introduction to Gears" and an in-depth "Gear Technical Reference" are also available. No registration required.
Click here to learn more.

New adhesive for automotive lighting

DELO has developed PHOTOBOND OB4189, a new adhesive for automotive lighting applications. It is extremely resistant to yellowing and, with its high aspect ratio, is particularly suitable for bonding microlens arrays, such as those found in headlights and projection systems. The adhesive also retains its shape after dispensing and does not flow, which is important for bonding microlens arrays.
Learn more.

Which parts should be 3D printed? AI combs through CAD files to find out

One of the biggest challenges in transitioning to additive manufacturing (AM) is the ability to identify which parts are best suited for the process quickly and easily. Learn how Danfoss, Stanley Engineered Fastening, and even the U.S. military have utilized advanced additive manufacturing software to automate the process, reducing material waste and energy costs, improving part reliability, decreasing lead times, as well as now having the ability to identify part consolidation opportunities through intelligent AM decision-making.
Read the full article.

9 key design tips for injection molding

Keep costs down and quality up all while optimizing your injection molded designs with these helpful tips from Xometry. Learn how to build better injection molded parts and products -- using draft angles, ribs and gussets, radii, fillets, and more -- and set expectations for the injection molding process. Good info here.
View the video.

Metal additive manufacturing: Rocket turbopump design

Mixing undergraduate curiosity and real-world engagement, two students from Colorado University Boulder Aerospace Engineering Sciences program, Zachary Lesan and Patrick Watson, started an independent effort on turbopump design and manufacture that is a lesson in determination and industry collaboration. With lots of supplies and advice from industry heavy hitters including Velo3D, CFturbo, SpaceX, and many more, their project has reinforced significant points being made about next-generation rocketry.
Read the full article.

Easy-to-detect plastic parts: Food processing

Foreign materials have no place in food, and yet undesired contamination makes its way into production processes time and time again. JW Winco has established a new line of standard parts made of plastic that are easy to detect -- visually and with metallic sensors -- even in pasty and opaque media. The visually detectable (VD) knobs, cabinet U-handles, hinges, hand levers, and three-lobe knobs are made of solid-colored blue plastic. The metal detectable (MD) standard parts are also made of blue plastic but contain additional additives with iron oxide. These parts can be used in both the food and pharmaceutical industries without reservation.
Learn more.

VariBlast air gun for safe and efficient blowoff

Safety and efficiency are coupled with ergonomic design and engineered air nozzle technology to produce the VariBlast Precision Safety Air Gun -- an essential tool for processes needing a handheld and effective blowoff solution. The lightweight unit with variable flow trigger from EXAIR provides a focused blast of air capable of handling tough jobs with remarkable ease.
Learn more.

Linear bushings with 70% longer service life

Bosch Rexroth's segmental linear bushings with plastic cage are used in a wide variety of industries to achieve a load capacity that is up to 20% higher and a service life that is up to 70% longer. They are part of a Rexroth round guide with a matching shaft. The particularly light and short linear bushings allow long working spaces and offer additional sealing options. They are also available as linear sets. Use the Linear Motion Designer (LMD) calculation program to select the right linear bushing for your needs.
Learn more.

Robotic machining just got a whole lot better! All-electric force compensator for robotic sanding, grinding, and deburring

SUHNER's new end-of-arm EFC-02 active compliance system combines over a century of abrasives and material removal expertise with smart automation to deliver precise, constant force for robotic sanding, grinding, and deburring processes. The result is superior, consistent surface quality. EFC-02 is used for material removal or surface finishing -- even in tight or narrow spaces. It features simple robot programming for complex processes, Industry 4.0 functionality, and is fully compatible with angle grinders, orbital sanders, angle polishers, and straight grinders. Optional automatic changers for abrasives or belts are available.
Learn more and see how this new SUHNER innovation works.

Ultimate guide to metal 3D printing with binder jetting technology

Desktop Metal has published its ultra-informative "Metal Binder Jetting Guide," a 40-page resource that will help interested parties explore binder jetting technology, which does not use a laser, and how it compares to other metal 3D-printing processes. Take a deep dive into what makes binder jetting a standout technology, and learn how it works, its many benefits, and real-world case studies of successful adopters.
Learn more.

New clamping innovation for precise 5-axis machining

The versatile Modular Pull Clamping System from Fixtureworks is ideal for machining from five sides with no tool interference and no need for additional machining setup. This innovative solution with a compact cylindrical design helps users achieve secure, precise workholding quickly and easily. It can be used as a mechanical zero-point clamping system for quick fixture change with 0.005-mm accuracy.
Learn more.

Real-world applications: Replacing hydrodynamic fluid film bearings with modern rolling element bearings

SKF's Evolution magazine has an informative article about the benefits of replacing hydrodynamic fluid film bearings with modern rolling element bearings. Real-world applications cited include turbochargers and crankshafts, screw expanders that drive electricity generators in a geothermal power plant, and industrial chillers and heat pumps. Very interesting with technical info.
Read the full SKF article.

New HUCO nylon sleeve gear couplings catalog

The new and downloadable HUCO NSG Couplings Catalog features flexible molded nylon sleeve couplings with a double crowned tooth design that provide free axial movement, low friction, no heat buildup, and minimal stress during misalignment. Designs are available with up to 9.5-mm axial travel. With this no-maintenance design, the load is distributed near the center of the tooth for maximum strength.
Get all the specs.

Can your rooftop handle solar panels? Sandia tests say 'probably so'

An analysis of rooftop structural strength by Sandia National Laboratories provides a new tool in evaluating homes for solar installations. [Photo courtesy: Sandia National Laboratories]

 

 

Most U.S. rooftops in good repair can take the weight of solar photovoltaic (PV) systems. That's the conclusion of a three-year study by a research team led by Sandia National Laboratories.

"There is a misperception in the building industry that existing residential rooftops lack the strength to carry the weight load of rooftop solar photovoltaic installations," said Sandia structural engineer Steve Dwyer. "Most existing well-built wooden rooftops can support PV system loads."

Sandia took on the job of analyzing rooftop structural strength to address concerns raised in the U.S. Department of Energy's (DOE) Solar America Cities program. The agency named 25 cities to promote adoption of solar technology at a comprehensive, local level through photovoltaics.

At least one city reported the primary barrier to solar was the difficulty and cost of obtaining construction permits for rooftop solar installations because of structural issues. "I couldn't believe it was a problem," said Dwyer, who led the Sandia test team. "Solar PV systems represent little additional weight, and roofs are very strong."

He said many code officials aren't familiar with solar technology and lack the training to evaluate how a solar PV system might affect roof structure. So they bring structural engineers into the permitting process, adding time and money for the system owner and the solar contractor. Often, they then deny engineering certification for solar PV installations on wood roofs, declaring the structures too weak.

Load-bearing capacity is several times higher
In two, first-of-their-kind studies funded by DOE's SunShot Initiative -- which seeks to make solar energy cost competitive with other energy sources by the end of the decade -- and conducted in partnership with the University of New Mexico (UNM), Sandia stressed wood rooftop structures to the point of failure and compared the data with allowable loads identified in the International Residential Code and the National Design Standard.

They concluded the actual load-bearing capacity for residential rooftop structural systems is several times higher than the calculated values.

In a University of New Mexico lab, roofs were built and stressed to the breaking point to show the solar permitting community how strong they are. The tests were done by Sandia National Laboratories in partnership with UNM. [Photo courtesy: Sandia National Laboratories]

 

 

 

 

Sandia hopes engineers and permitting officials will use the results when they make decisions about rooftop strength and solar PV applications, increasing the number of safe, cost-effective rooftop solar PV installations.

"Safety is a crucial factor in building codes and must be considered when there is any change to a structure," Dwyer said. "Understanding how weight loads affect the structural integrity of a roof is important to homeowners, code officials, solar installers, and builders. These results provide a new tool and set of data for consideration in evaluating rooftops for solar PV installations."

The roof acts as a whole
Dwyer said engineers doing rooftop structural analysis often calculate stresses on the basis of an individual beam, rafter, or truss. That approach assumes each component of the structure acts alone. "It fails to consider the rooftop system as a whole or consider the load-sharing or load redistribution effects of a roof system," he said. "The result is a conservative analysis that does not accurately represent the roof's ability to support a PV installation. It's not a fair assessment."

And he said engineering evaluations are not universally applied across cities and states. "Some do them, and some don't," he said. "Local governments pick and choose what they accept. Not everybody uses the same method, so it can be difficult for solar installers and residents to know what to expect. All these issues have posed serious challenges to the solar industry."

Dwyer said the Sandia team realized building codes won't change, so they tackled the problem by building some roofs, breaking them, and showing the permitting community just how strong a roof is. Starting about three years ago, the team built different roof sizes in a UNM lab.

"We did a lot of testing," Dwyer said. "First, we wanted to be sure we were on the right track. We thought, 'OK, the engineers are not giving credit for load sharing,' so we tested a two-by-four, broke it in half, then nailed a piece of sheeting to it to see if it added strength. It did, 35 percent with nailing and 74 with gluing. We were on the right track."

They built scaled versions of roofs in different lengths with five rafters or trusses 8 to 20 feet long and applied a uniform load over the whole thing. "We used air as the load," Dwyer said. "We built bladders of different sizes and used them to put pressure on top of the roof by filling them with air at up to 144 pounds per square foot. We broke every size rafter and the more commonly used trusses, five sets of each."

On average, the rafter-based tests demonstrated a 330 percent excess load-bearing capacity compared to values computed in the National Design Standard. "This suggests that current rooftop structural evaluations are overly conservative in evaluating the ability of roofs to support additional loading from solar PV installations," Dwyer said. "A well-built home that meets local building standards and has not been adversely modified or damaged should have enough load-bearing capacity to support a roof-mounted PV system."

You can learn more about Sandia's energy programs here.

Source: Sandia

Published May 2016

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