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March 8, 2012 A Penton Media Publication Tune in to EngineeringTV.com RECYCLING THERMOFORMED PACKAGES, page 20 LOOKING GOOD WITH STRUCTURAL THERMOSETS, page 42 SETTING STANDARDS FOR BEING GREEN, page 48 MORE FOR LESS WITH OSCILLOSCOPES, page 58 Supplying reliable quality components for the automation and control industries www.altechcorp.com 4ALKABOUTABUNDLE OFADVANTAGES s%# TECHNOLOGY FROM EBM PAPST GIVESYOUMORECONTROLOPTIONS FOR ADVANCED APPLICATIONS THAN !# TECHNOLOGY  AND ITS HIGH EFlCIENCY ALSO SAVES A WHOLE LOT OF ENERGY s&URTHERMORE IT PROLONGSTHESERVICELIFE OFAIR CONDITIONINGAND REFRIGERATIONSYSTEMSAND MAKESTHEIROPERATIONMUCH QUIETER s4HE ELECTRONICS ARE COMPLETELY INTEGRATED INTO THE MOTOR MAKINGTHESETRULYhPLUGANDBLOWvFANS s/NEMORETHINGOUR%#TECHNOLOGYENABLESYOUTOCREATEANENERGY SAVING BUNDLEOFSEVERALHUNDREDFANSANDCONTROLTHEMFROMASINGLEWORKSTATION &ORAWHOLEBUNDLEOFINFORMATION VISIT www.ebmpapst.us/hyblade The engineer’s choice RS# 101 Industrial Pressure Gages Very High Accuracy Digital Pressure Gage DPG409 Starts at • NEW RANGES! $695 Sealed Gage Optional Wireless Compound Gage Transmitter Available Vacuum and Barometric Ranges • 5-Point NIST Traceable Calibration Included • High 0.08% Accuracy on Most Ranges • Selectable 4 to 20 mA, 0 to 5V or 0 to 10V Analog Output • Large Backlit Display with 25 mm (1") Digits • 11 Selectable Pressure Units Visit omega.com/dpg409 © Damlanpalus / Dreamstime.com General Purpose Digital Pressure Gage DPG8000 Series $360 Visit omega.com/dpg8000 Industrial Digital Pressure Gages DC-, Loop-, or Battery-Powered Models DPG9000 Series Starts at $425 DPG 2001B Series Starts at $349 Visit omega.com/dpg2001b Visit omega.com/dpg9000 omega.com ® Because of transmission frequency regulations, these wireless products may only be used in the United States and Canada (915 mHz models) or Europe (868 mHz models). Digital Pressure Gages No. ® RS# 102 © COPYRIGHT 2012 OMEGA ENGINEERING, INC. ALL RIGHTS RESERVED VOLUME 84 ISSUE 3 MARCH 8, 2012 MATERIALS The advantages of STRUCTURAL THERMOSETS FEATURES Structural thermosets are an attractive alternative to metals and thermoplastics, thanks to excellent physical properties and surface appearance. From car-body panels and helicopter parts to electrical enclosures and sporting goods, manufacturers increasingly rely on structural thermoset sheet-molding compound (SMC) and bulk-molding compound (BMC) to address demands for strong, light, and durable materials. Due to intrinsic limitations with metals and thermoplastics, many engineers are turning to structural thermoset compounds to bolster strength and corrosion resistance. The strong molecular bonds inherent in thermosets impart a tight web of inner connectivity that lets these materials maintain excellent structural properties despite prolonged exposure to chemical and temperature extremes. The materials also increase design flexibility for engineers and production efficiency for manufacturers. Here’s a closer look. Authored by: Larry Landis Director of Technology and Quality IDI Composites International Noblesville, Ind. advantages of structural 42 The thermosets Structural thermosets are an attractive alternative to metals and thermoplastics, thanks to high strength, light weight, corrosion resistance, and excellent surface appearance. Edited by Kenneth J. Korane [email protected] Key points: • Structural thermoset compounds have higher tensile and flexural strength per unit weight than do most metals. • Cross-linked molecules keep structural thermosets dimensionally stable at high temperatures. • Unlike common metals, structural thermosets won’t rust or corrode outdoors or in harsh environments. Components often last for decades with little maintenance. Structural thermoset basics Structural thermosets are distinguished from standard thermosets by their use of more specialized resins and higher levels of reinforcement — glass, carbon, and aramid fibers, for example. The added reinforcement increases strength and stiffness, while resins protect the fibers and improve the compound’s overall physical properties. Moreover, manufacturers can tailor these properties by varying ingredients. For example, changing fiber type, length, and mix proportion alters its flow, strength, and Resources: IDI Composites International, www. idicomposites.com 42 MACHINE DESIGN.com Structural thermoset SMC and BMC materials offer a number of advantages over metals and thermoplastics, including higher strength per unit weight, better dimensional stability and corrosion resistance and, often, lower cost. MARCH 8, 2012 rigidity; varying resin concentration and type affects overall strength, along with the compound’s heat or corrosion resistance. Heating the material as it is molded forms three-dimensional covalent bonds between polymer molecules. This process, known as cross-linking, is irreversible. Therefore, cross-linked materials cannot be melted and reshaped. The term “thermoset” accurately describes this chemistry. Cross-linking creates a rigid 3D molecular structure that lets thermosets maintain the desired physical and electrical properties during prolonged exposure to adverse conditions such as excessive heat. This distinguishes thermosets from thermoplastics, which are generally unsuitable for high-temperature environments because they can be remelted after solidification. Thermosets tolerate heat-distortion temperatures (HDT) and glass-transition temperatures (Tg) that would literally melt most thermoplastics. Three of the most common thermoset resins are polyester, vinyl ester, and epoxy. Each has its own price and performance characteristics, so base selection on an application’s functional and cost requirements. For example, engineers might choose vinyl-ester resin for corrosionresistant products, epoxy for high-strength applications, and polyester when good overall performance and cost are the driving factors. As for reinforcement, many types of fibers can be used depending on the molding process and strength requirements. Glass-reinforcement options include choppedstrand, mat with random-fiber orientation, light textile fabrics, heavy woven materials, knitted materials, and unidirectional fabrics. Carbon-fiber reinforcement is used for applications that require exceptional strength coupled with severe weight restrictions. Structural thermoset SMC Most structural thermosets are in the form of sheetmolding compound. SMC is a cost-effective, lower-weight alternative to many metals. Standard SMC contains 10 to 30% reinforcement, while structural grades are typically in the 40 to 65% range. Reinforcement is normally choppedstrand glass fibers 0.5 to 2.0-in. (12.7 to 50.8-mm) long. Structural-thermoset SMC is manufactured in a continuous process that combines a viscous paste and glass fiber on specialized equipment with a continuous web. Paste containing the resin and additives is poured onto a carrier film, then cut glass fibers are added, along with a second layer of film. The paste and glass between top and bottom carrier films creates a thin “sandwich” that is run through a series of serpentine rollers. The serpentine action and resulting pressure causes the paste to coat MARCH 8, 2012 42 880: Sustainability for 48 ULE Manufacturing Organizations Just because a company states they operate in a sustainable fashion doesn’t make it so. New procedures from UL E help confirm their claims. 49 MACHINE DESIGN’s LITERATURE EXPRESS your father’s 58 Not oscilloscope Oscilloscope readings on a Web page? Even low-end oscilloscopes can provide output in a variety of formats that make measurements more useful. 62 Synchronous technology can move between What’s hot in CAD history-based and direct modeling. The next step in realistic CAD — stereoscopic design? ...And more. ELECTRICAL & ELECTRONIC Not your father’s Even less-expensive oscilloscopes provide data in a variety of formats once available only from top-ofthe-line instruments. OSCILLOSCOPE Like most technologies, oscilloscopes have evolved over time. Digital-storage oscilloscopes, or DSOs, are now the preferred type for most industrial applications. And features that once were available only on expensive, premium DSOs are now becoming commonplace on even “nonWindows” scopes that start in the $2,000 range. Upgradable bandwidth, deep memory, large displays, and fast update rates are just a few examples. In the past, only higher-end oscilloscopes have offered Oscilloscope display via iPad: Today VNC clients can be used to control features such as Ethernet Windows-based oscilloscopes via mobile platforms such as the iPad. and USB connections. Less-expensive offerings have gone beyond floppyenable this connection, you connect a USB cable between drive storage and GPIB programming. a USB Host port on a PC and the USB Device port on the New connectivity options have started to trickle down oscilloscope. to less-expensive oscilloscopes. In almost all cases, USB A USB Device connection typically involves some sort has replaced floppy drives as the de facto connection of driver library. Scopes from Agilent Technologies Inc., on oscilloscopes. Now to save a screen or data file, usSanta Clara, Calif., for example, use an IO Library, which ers simply insert a USB thumb drive into a connection includes a connection expert program to assist with setting typically referred to as a “USB Host.” Some oscilloscopes up the link to the scope. With the connection established, today can support USB thumb drives up to 128 Gbytes remote commands can control the oscilloscope. of storage. In addition to USB Host connections, many oscilloscopes now have USB Device connections. Instead Ethernet connectivity of being used to connect thumb drives, these connections permit remote control of oscilloscopes via USB. To While USB connectivity has been relatively common 58 MACHINE DESIGN.com MARCH 8, 2012 58 Access our Reader Service Web site to quickly find and request information on the products and services found in the pages of MACHINE DESIGN. www.machinedesign.com/rsc 2 MACHINE DESIGN.com MARCH 8, 2012 MACHINE DESIGN.com 43 Parts you use every day, at everyday great prices We’ve got the pneumatic parts you need, and they ship the same day* New are quick-disconnect hose couplings, which allow easy changing of tools or hose connections. Brass fittings work with water, oil and many compressed gases. Aluminum manifolds give you flexibility in designing a system. And everyone needs a blow gun in their tool kit! See everything at: www.automationdirect.com/pneumatic-parts Also Available Start at: Aluminum Manifolds • • $6.75 Round manifolds with 3/8 inch NPT input, and two or three 1/4 inch NPT outputs Rectangular models with 1/2 inch NPT inputs on either end, and three or five 1/4 inch NPT outputs Start at: Brass Threaded Fittings • • • • $4-p.0ac0k) (5 10 different styles, including Tee and elbow Male and female connectors in 1/8 to 1/2 inch sizes Work with water, oil, air and other gases Maximum pressure 800 psi Quick-disconnect Air Couplings Pneumatic Air Cylinders Tubing and Hose • • • Start at: $5.00 Plugs and couplers for 1/4 and 3/8 inch hose sizes Male and female NPT threaded Compatible with three of the most popular connection styles Start at: Pneumatic Blow Guns • $4.25 Palm type with safety tip, pistol grips, pocket style, and plastic grip with flexible nozzles in various lenghs Fittings and Air Couplings www.automationdirect.com Go online or call to get complete information, request your free catalog, or place an order. Pneumatic Solenoid Valves and Manifolds 1-800-633-0405 Air Preparation RS# 103 ON THE COVER DEPARTMENTS A geometry being created in a PolyPlane.com video tutorial. 8 EDITORIAL Old codgers always gripe about “the kids” 10 EDITORIAL STAFF 12 LETTERS 16 SCANNING FOR IDEAS Rack-and-pinion lubricator ensures smooth operation and a long life Enclosure protects electronics and controls from harsh environments 20 28 33 34 REPORTER’S NOTEBOOK LOOKING BACK SENSOR SENSE COMMENTARY Problems with pre-engineering education? 36 BERKE ON SAFETY GFCIs — What they are and are not 38 VANTAGE POINT Don’t wait for government to address skills gaps — Mark C. Tomlinson 40 INVENTOR’S CORNER Spiral-chambered turbine engine packs a one-two punch 68 FE UPDATE The role of parametric CFD analysis in design 71 PRODUCT SPOTLIGHT Cylinders & valves 74 76 77 78 78 79 4 PRODUCTS AD INDEX BUSINESS INDEX CLASSIFIEDS BUSINESS STAFF BACKTALK MACHINE DESIGN.com For customized article reprints and permissions please contact: Penton Reprints, 1-888-858-8851, e-mail at [email protected] or visit pentonreprints.com. Editorial content is indexed in the Applied Science Technology Index, the Engineering Index, SciSearch and Research Alert. Microfilm copies available from National Archive Publishing Company (NAPC), 300 N. Zeeb Rd., P.O. Box 998, Ann Arbor, MI 48106-0998, Ph: 734-302-6500 or 800-420-NAPC (6272), extension 6578. Permission to photocopy is granted for users registered with the Copyright Clearance Center (CCC) Inc. to photocopy any article, with the exception of those for which separate ownership is indicated on the first page of the article, provided that the base fee of $1.25 per copy of the article, plus $.60 per page is paid to CCC, 222 Rosewood Dr., Danvers, MA 01923 (Code No. 0024-9114/12 $1.25 + .60). Subscription Policy: MACHINE DESIGN is circulated to research, development, and design engineers primarily engaged in the design and manufacture of machinery, electrical/electronic equipment, and mechanical equipment. To obtain a complimentary subscription see our Web page at submag.com/sub/ mn. For change of address fill out a new qualification form at submag.com/sub/mn. Printed in U.S.A., Copyright © 2012. Penton Media, Inc. All rights reserved. MACHINE DESIGN (ISSN 0024-9114) is published semimonthly except for a single issue in January, February, June, July, and December by Penton Media, Inc., 9800 Metcalf Ave., Overland Park, KS 66212. Paid subscriptions include issues 1-18. Issue No. 19 (OEM Handbook and Supplier Directory) is available at additional cost. Rates: U.S.: one year, $139; two years, $199;. Canada/Mexico: one year, $159; two years, $239; All other countries: one year, $199; two years, $299. Cost for back issues are U.S. $10.00 per copy plus tax, Canada $15.00 per issue plus tax, and Int’l $20.00 per issue. Product Locator, $50.00 plus tax. Prepaid subscription: Penton Media (MACHINE DESIGN), P.O. Box 2100, Skokie IL 60076-7800. Periodicals Postage Paid at Shawnee Mission, Kans., and at additional mailing offices. Can GST #R126431964. Canadian Post Publications Mail Agreement No.40612608. Canada return address: Pitney Bowes, P.O. Box 25542, London, Ont., N6C 6B2. Digital subscription rates: U.S.: one year, $69; two years, $99;. Canada/Mexico: one year, $79; two years, $119; All other countries: one year, $99; two years, $149. MARCH 8, 2012 POSTMASTER: Send change of address notice to Customer Service, MACHINE DESIGN, P.O. Box 2100, Skokie, IL 60076-7800. The Truth About Compressed Air! If you think compressed air is too expensive and noisy - read this. The facts will surprise you! Compare these Blowoffs Facts about Blowers There are a variety of ways to blow the water from the bottles shown in the photo below, but which method is best? To decide, we ran a comparison test on the same application using four different blowoff methods: drilled pipe, flat air nozzles, Super Air Knife (each using compressed air as a power source), and a blower supplied air knife (using an electric motor as a power source). Each system consisted of two twelve inch long air knives. The following comparison proves that the EXAIR Super Air Knife is the best choice for your blowoff, cooling or drying application. Energy conscious plants might think a blower to be a better choice due to its slightly lower electrical consumption compared to a compressor. In reality, a blower is an expensive capital expenditure that requires frequent downtime and costly maintenance of filters, belts and bearings. Here are some important facts: The goal for each of the blowoff choices was to use the least amount of air possible to get the job done (lowest energy and noise level). The compressed air pressure required was 60 PSIG which provided adequate velocity to blow the water off. The blower used had a ten horsepower motor and was a centrifugal type blower at 18,000 RPM. The table at the bottom of the page summarizes the overall performance. Since your actual part may have an odd configuration, holes or sharp edges, we took sound level measurements in free air (no impinging surface). Drilled Pipe Blower Air Knife This common blowoff is very inexpensive and easy to make. For this test, we used (2) drilled pipes, each with (25) 1/16" diameter holes on 1/2" centers. As shown in the test results below, the drilled pipe performed poorly. The initial cost of the drilled pipe is overshadowed by its high energy use. The holes are easily blocked and the noise level is excessive - both of which violate OSHA requirements. Velocity across the entire length was very inconsistent with spikes of air and numerous dead spots. The blower proved to be an expensive, noisy option. As noted below, the purchase price is high. Operating cost was considerably lower than the drilled pipe and flat air nozzle, but was comparable to EXAIR’s Super Air Knife. The large blower with its two 3" (8cm) diameter hoses requires significant mounting space compared to the others. Noise level was high at 90 dBA. There was no option for cycling it on and off to conserve energy like the other blowoffs. Costly bearing and filter maintenance along with downtime were also negative factors. Flat Air Nozzles EXAIR Super Air Knife As shown below, this inexpensive air nozzle was the worst performer. It is available in plastic, aluminum and stainless steel from several manufacturers. The flat air nozzle provides some entrainment, but suffers from many of the same problems as the drilled pipe. Operating cost and noise level are both high. Some manufacturers offer flat air nozzles where the holes can be blocked - an OSHA violation. Velocity was inconsistent with spikes of air. The Super Air Knife did an exceptional job of removing the moisture on one pass due to the uniformity of the laminar airflow. The sound level was extremely low. For this application, energy use was slightly higher than the blower but can be less than the blower if cycling on and off is possible. Safe operation is not an issue since the Super Air Knife can not be deadended. Maintenance costs are low since there are no moving parts to wear out. Filters must be replaced every one to three months. Belts must be replaced every three to six months. Typical bearing replacement is at least once a year at a cost near $1000. • Blower bearings wear out quickly due to the high speeds (17-20,000 RPM) required to generate effective airflows. • Poorly designed seals that allow dirt and moisture infiltration and environments above 125°F decrease the one year bearing life. • Many bearings can not be replaced in the field, resulting in downtime to send the assembly back to the manufacturer. Blowers take up a lot of space and often produce sound levels that exceed OSHA noise level exposure requirements. Air volume and velocity are often difficult to control since mechanical adjustments are required. To discuss an application, contact: EXAIR Corporation 11510 Goldcoast Drive Cincinnati, Ohio 45249-1621 (800) 903-9247 Fax: (513) 671-3363 email: [email protected] www.exair.com/45/423a.htm The Super Air Knife is the low cost way to blowoff, dry, clean and cool. RS# 104 Blowoff Comparison Comp. Air Type of blowoff SLPM Horsepower Required Sound Annual Approx. Annual Purchase Level Electrical Maintenance Price dBA Cost* Cost First Year Cost PSIG BAR SCFM Drilled Pipes 60 4.1 174 4,924 35 91 $50 $4,508 $920 $5,478 Flat Air Nozzles 60 4.1 257 7,273 51 102 $208 $6,569 $1,450 $8,227 Blower Air Knife 3 0.2 N/A N/A 10 90 $5,500 $1,288 $1,500 $8,288 Super Air Knife 60 4.1 55 1,557 11 69 $518 $1,417 $300 $2,235 *Based on national average electricity cost of 8.3 cents per kWh. Annual cost reflects 40 hours per week, 52 weeks per year. What’s new online machinedesign.com FREE EBOOK: THE BASICS OF ROBOTIC MOTION There are all types of industrial robots, and most can be broken down into a handful of fundamental components. Among the most basic are the drives and controls. Engineers from MICROMO show how digital control of electrical, pneumatic, or hydraulic power affects robotic motion, and explain the differences to help determine the best design for your project. Download a copy at http://machinedesign.com/ebook/motion-control-mechatronics/the-basics-ofrobotic-motion-0118. Top 5 robots from CES 2012 Engineering TV highlights the most interesting robots on display at this year’s Consumer Electronics Show, including a low-cost quad-rotor UAV, modular robotic building blocks, and a mobile platform that uses a smartphone as the onboard brains. View them all at www. engineeringtv.com/video/Top5-Robots-from-CES-2012;OnlyEngineering-TV-Videos. EDITOR’S WEB PICKS Structural thermoset microsite 6 IDI Composites International’s new microsite focuses on structural-thermoset compounds. The materials resist corrosion and are durable, strong, and exceptionally light, making them viable alternatives to metals and thermoplastics. The site details various resins, reinforcement fibers, and specific SMC and BMC products, and gives an overview of markets and applications. See www.idicomposites.com/products/ structural-thermoset-compounds. Valve resource Peter Paul Electronics has launched a new Web site (http://peterpaul.com) that details the company’s valves and valve operators for fluid power, medical, food, transportation, and other markets. Resources include flow and conversion calculators, downloadable catalogs, and application assistance. An online valve configurator will be introduced later this year. 87,000 components The new Stock Drive Products/ Sterling Instrument Inch Catalog includes thousands of mechanicaldrive components, including timing belts, pulleys, clamps, bearings, gears, MACHINE DESIGN.com couplings, and vibration mounts. The 1,520-page catalog includes an 87-page technical reference section. Request or download a copy at www. sdp-si.com/D810/D810cat.htm. Ball-screw blog Steinmeyer has added a new blog to its Web site, www.steinmeyer.com. Content includes product design, engineering calculations, and commercial issues. Industry experts are available to offer advice on machine-tool, factory-automation, mechatronic, semiconductorequipment, and aerospace applications, and users are free to post comments. Visit the blog at www.ballscrew-tech.com. Motor-match tool Groschopp’s new Web site (www. groschopp.com) lets users precisely size fractional-horsepower motors and gearmotors. Motor Match is based on the company’s STP Calculator, where users enter two of three performance parameters (speed, torque, and power) along with motor type, gearbox type (if desired), and voltage. The software evaluates and matches desired performance to the motor size and specs from more than 4,200 products in the site’s database. MARCH 8, 2012 NEW VIDEO SERIES ON PID FOR PLCs ON OUR LEARN SITE PID for process applications can be tricky — this Series helps you understand the basics of implementing it using instructions available in a programmable controller. Our newest video series on the Learn Web site, PID for the Productivity3000 controller, starts with the basics. Part 1 features “What is a PID and what does it do?” Part 2 covers “How Does a PID work?” Part 3 shows an example of a PID loop in operation. Starting with Part 4, the videos delve into the details of how to configure the PID instruction in the Productivity3000 ladder program, and other supporting logic. There are a total of 11 videos in this series. Many are accompanied by handy downloadable training PDFs. Visit http://learn. automationdirect.com and navigate to the PLCs section for the PID Series (under “Productivity3000 – PID Loop Programming” tab). Dozens of additional videos are also available on topics ranging from data-acquisition software to drives and motors. 1 Unscramble the letters in the shaded boxes and enter the secret code at www.bestforcad.com/code for a chance to win a Dell Precision Workstation, NVIDIA GPUs or a Trek bicycle. You can also find puzzle answers there. 3 4 5 14 SOLVE your CAD puzzle 2 6 9 18 24 29 30 25 31 34 22 32 33 36 37 48 53 56 57 65 68 66 72 RS# 106 49 54 58 69 71 39 45 47 52 38 42 44 46 13 27 41 43 12 23 26 35 40 11 19 21 28 10 16 20 64 8 15 17 51 7 50 55 59 60 67 70 73 61 62 63 EDITORIAL Old codgers always gripe about “the kids” One of the many woes of today’s society, we are told, is that our schools are producing graduates totally unprepared to be a part of the workforce. Ammunition for that viewpoint comes from a recent study by the Social Science Research Council of 2,300 undergraduates, which discovered that 36% of them demonstrated no significant gains in critical thinking or written communication during their four years in college. Another survey found business leaders moaning that their new hires lacked, among other things, reading comprehension, a good work ethic, and writing skills. This hand-wringing has led to talk of a skills gap and what to do about it. But what seems to be absent in these discussions is a recognition of the fact that complaints about kids entering the workforce have been with us for as long as there have been older generations hiring younger generations. On that score, it is interesting to go back in time and see what managers thought of the young people they hired in the 1970s. Those youngsters, of course, are now the ones doing the hiring and complaining about the quality of people filling out employment forms. Managers of the time did not paint a pretty picture of the criticalthinking skills demonstrated by kids entering the 1970s workforce. “Increasingly we hear from leaders in business, professions, and government that it is easy to find people who can do what they are told, but difficult to find people who know what to do without being told,” lamented York University professor David Bakan in 1969. Nor were the communication abilities of that generation anything special. Researchers from Ohio University and Eastern Michigan University, writing in the Journal of Business Communication in the mid-1970s, found that many new graduates had grandiose views of their own abilities to write reports and convey concepts verbally that weren’t shared by their supervisors. I have concluded that some of the bellyaching about work skills is just an older generation forgetting how many facets of performance can come only from experience. If I am still around in 30 years, I fully expect to read about managers, who today are supposedly ill-prepared to hold down their first jobs, grumbling over the abject unreadiness of the kids. Finally, we should remember that academic excellence is only one piece of the puzzle when it comes to career preparation. On that score, consider the career of someone who might be the poster child for poor high-school preparation, Don Mann. In his autobiography, he relates how a teacher once inquired about the location of his textbooks. Mann had to admit he had dumped them in his locker the first day of school and had since forgotten where the locker was. This inauspicious start didn’t seem to slow Mann down, though. He eventually entered the Navy, earned two BS degrees and an MS degree, and retired as a SEAL/Chief Warrant Officer with a résumé that included time on the elite SEAL Team Six. Not bad for somebody who graduated near the very bottom of his high-school class. — Leland Teschler, Editor RS# 107 MARCH 8, 2012 Hundreds of Options, Models, Applications & Opportunities! Minimatic® Electronic Control Valves rd & ns a d n Sta m Desig o Cust Select ect Orifice ce Size e High High FlowLow Flow Various Connectorss Cycle Life in the Billions Fast Response Fluorocarbon, EPR, FKM and Silicone Seals Normally-Open Normally-Closed Fully-Ported 2-W y 2-Way 3-Way Oxygen Clean Series Numerous Mounting Options Fractional Wattage e FREE 360-Page Catalog b t IInc. Clippard Instrumentt L Laboratory, Providing innovative solutions for today’s engineering challenges 877-245-6247 • www.clippard.com RS# 108 ANOTHER LEE INNOVATION Cartridge Check Valves EDITORIAL STAFF Leland E. Teschler, Editor, [email protected] Designed for Installation into Plastics Kenneth J. Korane, Managing Editor, [email protected] • 100% Performance Tested • Simple Press-In Installation • Wide Range of Cracking Pressures • 2.5, 5.5, and 8 mm Sizes • All Stainless Steel SENIOR EDITORS Leslie Gordon, Stephen J. Mraz For more information, contact The Lee Company The Lee Company Innovation in Miniature 2 Pettipaug Road Westbrook, CT 06498 USA Tel: 860-399-6281 [email protected] AUTOMOTIVE & NEWS FEATURES Stephen J. Mraz, [email protected] CAD/CAM Leslie Gordon, [email protected] ELECTRICAL, ELECTRONICS “See us at Pittcon, Booth #1834 and ABRF, Booth #204” RS# 109 LOW COST, HIGH STRENGTH, PHENOLIC IMPREGNATED, “RESINITE” DIELECTRIC TUBING FOR COIL WINDING, INSULATING Robert J. Repas, Jr., [email protected] FASTENING, JOINING Jessica Shapiro, [email protected] FLUID POWER Kenneth J. Korane, [email protected] MANUFACTURING Leslie Gordon, [email protected] Kenneth J. Korane, [email protected] MATERIALS Jessica Shapiro, [email protected] MECHANICAL Kenneth J. Korane, [email protected] Jessica Shapiro, [email protected] The original, proven, “Resinite” insulating tubing presents a unique combination of low cost coupled with high mechanical strength and good dielectric properties. It will support lugs and terminals and can be fabricated to specifications. Will accept dip and hand soldering of terminals. Can be embossed for threaded cores. Also available in U/L flame retardant grade. To receive literature & details fast - www.pptube.com Phone: 847-537-4250 • Fax: 847-537-5777 • E-Mail: [email protected] EDITORIAL PRODUCTION Denise Greco, Editorial Production Manager Randall L. Rubenking, Art Director More Than 75 Years - The Original Paper Tube Company 1033 S. Noel Ave., Wheeling, IL 60090 10 MACHINE DESIGN.com MARCH 8, 2012 RS# 110 1300 E. 9th St. Cleveland, OH 44114-1503 Lubriplate ® The Essential OEM Lubricant Range... WHEN IT COMES TO SPECIFYING LUBRICANTS FOR ORIGINAL EQUIPMENT... Lubriplate ® CAN MEET YOUR REQUIREMENTS. • 142 Years of Lubrication Expertise • Factory Direct Representatives • Dedicated OEM Department • Vast Product Range - Both H-1 Food Grade & General Industrial • Worldwide Distribution Network Lubriplate’s Advanced, 100% Synthetic, Gear & Bearing Oils Include... PGO Series • Advanced, Ultra High-Performance, Polyalkylene Glycol (PAG)-Based, Gear, Bearing and Chain Lubricants. • Available in ISO Grades 150 through 680. Syn Lube Series • 100% Synthetic, Polyalphaolefin (PAO)-Based, Fluids for Gearboxes, Bearings, Chains and Recirculating Systems. • Available in ISO Grades 150 through 1000. Syn Lube HD Series • 100% Synthetic, PAO-Based, Extra Heavy-Duty Fluids. • Meets AGMA EP (Extreme Pressure) Requirements. Complete Lubrication Solutions! Backed By: Lubriplate ® ESP Extra Services Package For more information contact Ellen Girard, LUBRIPLATE’s OEM Marketing Analyst. 973-465-5731 • [email protected] RS# 111 • Complimentary Plant Surveys • Tech Support • Lubrication Software • Machinery Tags • Follow-Up Lubricant Analysis • Training LETTERS Engineering school: A hard-knock life You are dead-on regarding the life, and realities, of an engineering student (“ Tough Engineering Courses Now Make Headlines,” Dec. 8). For me, graduating and moving onto a “real job” was a welcome relief. No longer did I have to study for 16 hours a day, and often past midnight. Persistence and patience earned me a degree, not my limited 2.9 GPA or retak ing three classes be cause I initially got Ds in them. After graduation, working 10 to 12 hours a day and going home with nothing to do was a wonderful break in life. And I could eat normal food. (You forgot to mention that engineering students are dirt poor because they don’t have time to work. As a result, the diet during college was less than healthy.) Jim Stoor Great editorial. I couldn’t help but smirk when I read “She switched her major to psychology and policy management from electrical and computer engineering after a particularly tough assignment that ‘kept her and her partner in the lab well past midnight for several days.’” Several days? Getting a bachelor’s degree in mechanical engineering from the University of Illinois kept me in the lab or engineering library well past midnight almost every single night. Sure, thoughts of self-defenestration from the third-floor library window came to mind several times a semester out of sheer frustration. But who doesn’t love failing 80% of their exams after spending hundreds of hours preparing for them? At t h e e n d o f t h e d ay, I’m glad I stuck with it. I somehow managed to graduate with a 2.999 GPA, find a satisfying job, and have been enjoying going home at the end of the work day 12 MACHINE DESIGN.com instead of the library for the past seven years. Steven D. Springer I could not agree more with your editorial. I found engineering college difficult and completed my degrees only through sheer stubbornness. During my first year I took two accounting courses during which the head of the accounting department asked if I would consider switching majors. I was doing well and his impression was I had a gift for it but I politely declined. I wanted to be an engineer. I couldn’t imagine really doing anything else. I, too, put in many late nights, and getting my BS degree was arguably the hardest accomplishment in my life, but it has made me happy, successful, and I continue to learn. It’s unfortunate that students would change majors to improve their grades rather than pursue their passion. Perhaps they weren’t quite so sure why they started in engineering in the first place. MARCH 8, 2012 That passion began for me at an early age. I think it stems from the freedom given me by my parents to take things apart to see how they worked (without overconcern for the consequences) and my desire to invent, refine, and make things through trial and error. This included everything from my bicycle to kitchen appliances to model rockets, even my parents cars. My parents were not technically minded, so they gave me the support where they could, mostly by giving me the freedom to try. My fourth-grade daughter is currently a victim of the modern school system in which so much emphasis is put on the metrics of mastering tests — reading, writing, math. It leaves no time for science. In contrast, I recall having a biology textbook in fourth grade. So I don’t see the support from our school system needed to grow that interest and passion for science. Therefore, I do what I can to interest my children in science. Adrian van der Kroef Name Dr. Dennis Hong Job Title Associate Professor of Mechanical Engineering, Virginia Tech Area of Expertise Robotics LabVIEW Helped Me Convey and respond to vast amounts of data in real time Latest Project Design and prototype a car that can be driven by the blind in just 4 months NI LabVIEW LabVIEW makes me better because saves time and effort >> Find out how LabVIEW can make you better at ni.com/labview/better RS# 112 ©2010 National Instruments. All rights reserved. LabVIEW, National Instruments, NI, and ni.com are trademarks of National Instruments. Other product and company names listed are trademarks or trade names of their respective companies. 2780 800 453 6202 LETTERS Advice to those listening I couldn’t agree more regarding your advice for our job seekers and “occupy wall streeters” (“Advice for Occupy Wall Streeters,” Nov. 17.) Whoever thought they would be well suited for employment with a liberal arts or history degree, even 20 years ago, was dreaming all the way through college! I have to admit I haven’t kept up with the news on this, and more specifically, on their complaints. But I have heard people chastise them for wanting handouts and freebies. I can more than sympathize with the movement in strict regard to the prevalent, in-situ greed on Wall Street and rampant corruption in our government. I wish we could send most of the guilty parties to jail, but there’s not enough room as we have to make way for some of the politicians and federal workers who egregiously helped create the quagmire we now find ourselves in. My son has just started high school and you can bet I’m going to give him the same advice as you advocate, not just for his own future, but for the future health and prosperity of the good old USA as well. I appreciate the candor and succinct advice your editorial so eloquently provides. Scott J. Sanders I read your editorial this morning and smiled. I graduated 10 years ago from Western Michigan University with a Liberal Arts degree in music and Spanish linguistics. My first job out of school was cutting steel and drilling holes in a machine shop owned by my friend’s dad. Thanks to that experience, I now work for an engineering firm in Tennessee. I also own a machine shop that supplies prototypes to our company. It’s a whirlwind, but it’s allowed me to provide for a growing family and let my wife stay home with our children since the birth of our first child. (She graduated with a bio-chem degree from WMU.) You are wise to suggest that young graduates learn how to weld or run a CNC machine. I’d hire them. Jon Rogers I had a couple of other letters from liberal arts degree holders who took what I said the wrong way. Regardless of what your degree happens to be in, I’d say learning a skill at a community college, if necessary, is a good way to get a foot in the door. — Leland Teschler ® RS# 113 14 MACHINE DESIGN.com MARCH 8, 2012 Real parts. Really fast. A product development team needs parts to meet its rapidly approaching deadline. Upload 3D CAD file. Machining begins. 1-10 parts How Many Parts? 10-10,000+ parts Receive FirstQuote® interactive quote. Receive a ProtoQuote® interactive quote. Finalize options, order with credit card or P.O. Computerized automated toolpaths sent to CNC Machine. Finalize quote and submit P.O. Part ready for shipping. Mold design and milling. Part ready for shipping. Receive order confirmation with gate and ejector layout. Approve. Part production. 1–3 Days 1–15 Days Check out our video design tips! It’s easy to work with Proto Labs. Just upload your 3D CAD model and choose the best process for your project: CNC machining in 1–3 days or injection molding in 1–15 days. Real parts in real materials, in days—not weeks. And that’s the real story. ©2012 Proto Labs, Inc. ISO 9001:2008 Certified GET YOUR PROTOGAMI! RS# 114 ITAR Registered Our Protogami design aid is a cool hexa-kaleidocycle that shows the effect of materials on finishes. Visit www.protolabs.com/parts today and request your free Protogami! Enter code MA12B. Call 877.479.3680 or visit www.protolabs.com SCANNING FOR IDEAS Edited by Stephen J. Mraz Rack-and-pinion lubricator ensures smooth operation and a long life The lubrication subsystem from Wittenstein, Bartlett, Ill. (www.wittenstein-us.com), keeps rack-and-pinion drives lubricated, preventing gears from becoming scratched and worn. The device works with the company’s drives as well as others on the market. The subsystem consists of a canister that holds Microlube GB, a mineral-oil-based NLGI grade 0 grease. The canister comes in 125 and 475-cm3 sizes. There’s also a sensor that alerts users when the canister is nearing empty. Rack-andThe lubricating pinion drive fluid flows from the canister to the mounting shaft through a plastic hose. Holes in the shaft let the lubrication fluid Pipe clamp for mounting 150-mm-long cable lets a machine operate the lubricator. Transparent canister Grease reservoir Sensor monitors how much grease is in reservoir Aluminum hose connection Plastic hose pass through to a felt pinion. This pinion then distributes lubricant onto the rack. Users program the device using a series of dip switches that open a valve and dispense a given r formation via ou number of “grease-gun Request free in Web site at ice rv Se er ad Re strokes” each day (a greasec design.com/rs gun stroke equals a cubic ww w.machine centimeter), a value that can range from 0.3 to 4. That setting can then be used for anywhere from 14 days to 18 months. A chemical reaction in the grease builds up pressure, which moves the grease through the various pipes and hoses. The unit operates in temperatures from 10 to 50°C. RS# 401 16 MACHINE DESIGN.com MARCH 8, 2012 For information on another case-hardened rack, scan this code or go to: http://machinedesign.com/ content/case-hardenedrack-0928 SM YOU’LL CALL IT the most technologically advanced process for customer-focused solutions in extruded aluminum. Sapa innovation turns visions into leading end-use products with advanced engineering, technical competencies and unprecedented resources. • Operations in 30 countries /16 plants in North America • Unmatched capacity and product capabilities • World class technical and design assistance • Service and integrated logistics focused on you Profiles Engineered for Your Success From automotive to building and construction, distribution to renewable energy, Sapa ALUMINOLOGYSM means finding answers to today’s toughest design challenges. One Company, One Call, Unlimited Solutions 877-710-Sapa | www.sapagroup.com/na RS# 115 SCANNING FOR IDEAS Enclosure protects electronics and controls from harsh environments The Hygienic Design (HD) enclosures from Rittal Corp., Urbana, Ohio (www. rittal-corp.com), are built to be easily and quickly cleaned while keeping the contents safe from water and chemicals. Engineers took care to ensure there are no cracks or crevices that could hide debris. For example, smaller HD enclosures have stainless-steel screw covers while large versions use internal hinges on the doors. The walls and door surfaces are angled to prevent anything from sticking to them and to let water run off of the surfaces rather than pool. The enclosures can mount on walls using rounded Roof projection eases Sloped roof for stand-off brackets. pressure on seals debris-free cleanout The brackets leave room behind the enclosure so water can flow around the entire unit during wash downs. For large enclosures, optional leveling feet keep the box off the floor and properly plumbed despite an uneven Internal hinges floor. A wire shelf eliminate can also be added crevices which to help route can trap debris cables. All mounting threads are covered to keep them free of debris. Available to A continuous siliNEMA-4X cone gasket around specifications the door fits into a precise channel that creates a tight seal without using adhesives. This makes it easy to remove or replace the gasket if needed. The blue-colored gasket ANSI stainless steel with ensures any particu400-grain brushed surface late splashed on it stands out so it can be removed. All these features, including the 400-grain brushed-steel surface finish, reduce cleaning times and the amount of water and detergents used. They also significantly lower the risk of contamination. The enclosures are also available in configurations that meet NEMA-4X specifications. RS# 402 18 MACHINE DESIGN.com MARCH 8, 2012 Door chamfered all around edge, which simplifies cleaning Continuous silicone seal and gaskets fit without adhesives. They can be replaced without using special tools For more information on enclosures, scan this code or go to: http://machinedesign.com/article/ nanotechnology-keeps-enclosuresclean-0524
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