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Tài liệu Machine design, tập 84, số 17, 2012

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November 8, 2012 A Penton Media Publication Tune in to EngineeringTV.com HOW HOT RODDERS SOUP UP ELECTRIC MOTORS, page 20 HOW TO MAKE CAM FOLLOWERS IN PLASTIC, page 38 HOW TO MAKE PLASTIC OUT OF PLANTS, page 46 HOW TO DODGE DANGER WITH AIR LOGIC, page 60 Microhydraulics. Macro capabilities. So much reliability and performance, in so little space. Creating high-performance flow control on a micro scale has been The Lee Company’s exclusive focus for more than 50 years. And it’s been a successful mission, as evidenced by thousands of applied Lee Microhydraulics designs – ranging from less than 0.10 in. to 1.00 in. in diameter, and 0.1 to 68 grams, for operating pressures to 8,000 psi. But small size and light weight are just the beginning.There’s also absolute reliability built into every Lee component through 100 % testing and inspection. Zero defects. It’s a production benchmark that has enabled Lee to meet demanding application needs in all sorts of industries. Aerospace, medical instrumentation, automotive, machine tools and oil drilling, to name a few. The innovative problem solvers. We don’t just satisfy requirements. We also solve problems – whether by simple modification, or ground-zero design engineering. The Lee Company is the world’s most capable and proven source for hydraulic-component innovation. And we’ve documented this claim in extensive detail with the Lee Technical Hydraulic Handbook. An invaluable reference, the Lee handbook contains essential data on the entire Microhydraulics product line, which includes: Lee Shuttle Valves. Detented, spring-biased, inverse, loose ball and zero leak shuttle valves from 50-700 Lohms. Lee Safety Screens. Best protection for critical system elements. 75 to 500 micron hole size. Pressures to 7,500 psid. Lee Pri. Pressure relief valves in insert form. 50 to 400 Lohm capacity. 20 to 5,400 psid cracking pressures. Lee Directional Flow Control. 40 to 20,000 Lohms in metered direction. 12 to 470 Lohms in free-flow direction. Lee Restrictors. Single and multi-orifice restrictors. 200 to 2.2 million Lohms. Lee Shuttle Valve. Shown actual size. Designed to isolate the normal from the emergency hydraulic system. So small, it fits right into the head of an actuator. Lee Plugs. The best way to seal drilled holes to 32,000 psi. No O-rings, threads or sealants required. Lee Cheks. All-metal and zero-leak check valves. 4 to 400 Lohms. Innovation in miniature. Essential reading for designers of hydraulic systems. Send for your free copy. Westbrook The Lee Company 2 Pettipaug Rd, Westbrook CT 06498-0424 860-399-6281 Fax: 860-399-2270 1-800-LEE PLUG www.TheLeeCo.com • Gerrards Cross • RS# 101 Paris • Frankfurt • Milan High Performance Pressure Instruments New! Metric Models High Accuracy Transducers Micro-Machined Silicon for Pressure Measurement • 5-Point Agency Traceable Calibration Included • Metric Pressure Ranges PXM409 Series •10 mV/V, 0 to 10 Vdc, or 4 to 20 mA Outputs Starts at $475 • Gauge, Compound Gauge, Absolute, Vacuum and Barometric Pressure Ranges Available • Welded Stainless Steel Construction • 316 Stainless Steel Wetted Parts Visit omega.com/pxm409 Handheld Digital Manometer for Differential, Gage and Absolute Pressure High-Accuracy Pressure Calibrators Visit omega.com/pcl341 PCL341 Series Starts at $1495 Very High Accuracy Digital Pressure Gauge 316 SS Body, Analog Output and Optional Wireless Transmitter Visit omega.com/dpg409 HHP240 Series Starts at $408 DPG409 Series Starts at $695 Visit omega.com/hhp240 omega.com ® Because of transmission frequency regulations, these wireless products may only be used in the United States, Canada and Europe. ®  RS# 102 © COPYRIGHT 2012 OMEGA ENGINEERING, INC. ALL RIGHTS RESERVED VOLUME 84 ISSUE 17 NOVEMBER 8, 2012 MOTION CONTROL Rollers with polymer bearing surfaces work with aluminum rails, which cost far less than groundhardened-steel versions. How to … GET BETTER MOTION with plastic parts Nylon 12: The plastic of choice Polymer bearing surfaces resist wear, don’t need maintenance, and can run surprisingly fast. FEATURES to get better motion 38 How with plastic parts Rollers, cam followers, and other components used for moving parts can make good use of polymers to increase speeds, reduce wear, and resist chemicals and harsh environments. They’re also quieter than metal components. The polymer advantage Many engineers still believe that heavily loaded applications need metal rollers and cam followers. They are unaware that polymer bearing surfaces withstand enormous forces if designed properly. At Intech Power Core, Closter, N. J., for example, we’ve delivered polymer rollers that withstand 8-ton loads. These rollers have been used in ski lifts and rigs that can raise an entire building. But the primary task of most rollers and cam fol- 46 A biodegradable alternative to foam is grown NOVEMBER 8, 2012 ACHINE  How to … AVOID ELECTRICAL HAZARDS with Pneumatic controls are a viable option when electrical hazards can’t be tolerated. air logic Authored by: Kenneth J. Korane Managing Editor Key points: • Air logic functions like relays, switches, and counters, but uses compressed air instead of electricity. • Air-logic controls are preferred in wet or dusty conditions because they pose little danger of electrical explosion or shock. Resources: AOP Technologies, www.aoptec.com Clippard Instrument Laboratory, www.clippard.com from mushroom roots and agricultural waste. D ’s 49 MLiterature Express NOVEMBER 8, 2012 FLUIDPOWER TECHNOLOGY GUIDE clutches and brakes How to rid foam of petroleum MACHINE DESIGN.com lowers is to transmit motion rather than support loads. Regardless of their purpose, rollers and followers are commonly hybrid designs with polymer load-bearing surfaces over metal roller bearings or structural hubs. These hybrid components, often sized as drop-in replacements for standard-sized all-metal components, offer compelling technical advantages due to their use of polymers: • Self-lubricating. Engineering polymers best suited for rollers are self-lubricating, a property that last the life of the component. Bearing surfaces Authored by: made from these George Bartosh polymers never President require lubrica- Intech Power Core tion between the Closter, N. J. roller and rail. Edited by Stephen J. Mraz When combined [email protected] with lubed-forResources: life bearings, polymer surfaces Intech Power Core, www.intechpower.com For another feature on eliminate mainplastic parts, scan this tenance costs code or go to: http:// associated with machinedesign.com/ regular lubricaarticle/plastic-gearstion, even those outlast-metal-0506 scheduled after washdowns. 38 to design suppression 42 How circuits for electric Back-EMF in clutches and brakes may lead to erratic operation and a shortened life. Cam followers and rollers from Intech put a gravitycast nylon 12 bearing surface on metal hubs and roller bearings. Using nylon eliminates the need for lubrication and makes the components quieter than their all-metal counterparts. Engineers might only glance at the dimensions and load capacities of roller and cam followers to ensure they will fit in their design before placing an order. But they should pay closer attention because these components can make or break the performance of motion subsystems critical to a host of industrial machines. Choose the wrong roller or cam follower and your design can be destined for a shortened life plagued with maintenance headaches, contamination issues, and speed limitations. The wrong component can also drive up operating and manufacturing costs. The right components, by contrast, will contribute to a longer life of reliable motion that engineers and buyers expect. But how do you pick the right roller or cam follower for the job at hand? The trick is considering not just sizes and loads but also the materials that make up the roller’s bearing surface. 38 More importantly, self-lubrication puts an end to the loss of performance and catastrophic failures common when metal rollers and rails aren’t regularly lubricated. • Wear resistance. Metal-on-metal contact, even when both metal surfaces are lubricated, can result in excessive wear and galling. Metal-on-metal wear affects rollers and rails, which are far more expensive to replace. Plastic rollers eliminate this wear. • Clean running. Self-lubricated polymers eliminate two potential sources of contamination — stray lubricant and particulates from metal-onmetal contact. For this reason, polymer cam folFrom cheap plastics to the world’s most-exlowers and rollers are a pensive composites, many types of polymers have good choice for medical, been machined, molded, or cast into rollers, cam semiconductor, foodfollowers, and other power-transmission compoprocessing, and cleannents. Engineers at Intech focused their developroom applications. ment efforts on a proprietary, gravity-cast nylon • Smooth and quiet oper12 called Power-Core PA12GC. It combines several ation. Unlike metals, advantageous material properties. polymers can dampen From a materials standpoint, Power-Core mainshocks and vibrations. In tains its physical properties in a variety of operating cam followers, polymers conditions. This stability lets engineers accurately absorb the damaging predict the material’s behavior and life even when shocks and vibrations it’s exposed to varying moisture, temperature, and caused by reciprocating chemical levels. motion. This prolongs In particular, Power-Core’s stability despite the life of machine bear- high-humidity and even total immersion, makes ings, especially in high- it well suited to power-transmission applications. speed applications. Most high-performance polymers absorb moisIn rollers, damp- ture, swell, and lose tensile strength. Power-transing contributes to quiet mission components made from moisture-absorbmotion. Polymer roll- ing (hygroscopic) polymers can end up too weak ers typically run about to carry the loads they were designed for and too 10 dB quieter than their swollen to work with mating components. metal counterparts. Power-Core also dampens vibrations, which They run smoothly too, lets it reduce noise and absorb shock loads that thanks to their precise power-transmission components commonly see. roundness. For example, To make these components, Intech gravity total runout on a macasts nylon 12 over metal hubs or thermally installs chined nylon 12 cam it over rollers bearings to create the beginnings follower with a 1.5-in. of a cam follower, roller, or gear. These blanks are OD would be less than then precision machine into finished components. ±0.001-in. Gravity casting contributes to Power-Core’s low • Speed and efficiency. internal stresses that gives the polymer a uniform Polymer rollers facilitate crystalline structure. As a result, finished compohigh-speed, energy-effinents have a consistent machining resistance that cient motion in a three improves precision during manufacture and use. ways. First, polymer And under external load, the dense crystalline rollers weigh about 40% structure helps thwart stress-induced cracks and less than similarly sized swelling that sometimes lead to premature failure. metal rollers, reducing  RS# 621 Magnum Venus Plastech, www.mvpind.com ESIGN Electrical and electronic devices such as logic circuits, programmable controllers, and PCs normally control fluid-power and fluid-handling circuits. Such systems can also operate with “air logic,” controls that function like relays, switches, time delays, and counters. However, while the circuitry is similar, compressed air is the control medium instead of electric current. Air-logic controls are often preferred in wet or dusty environments because they pose practically no danger of explosion or electrical shock. Likewise, air controls cannot ignite explosive or flammable gases and vapors. And they’re rugged. Water can splash on the controls without affecting operations, and they tolerate dust and dirt. Air to avoid electrical 60 How hazards with air logic Pneumatic controls are a viable option when electrical hazards can’t be tolerated. 60 MACHINE DESIGN.com Air-logic controls for composites manufacturing rely on miniature valves, manifolds, and other components from Clippard Instrument Laboratory. logic can also be used on machines with fluid-power components but no electrical supply. Air logic does have disadvantages. Most common is a lack of understanding among maintenance personnel on how to read schematics and troubleshoot problems. Also, air logic with long control lines responds noticeably slower than electronics. That’s because control lines longer than 10 to 15 ft fill and exhaust slowly compared to near-instantaneous electrical signals. In addition, it takes NOVEMBER 8, 2012 60 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 NOVEMBER 8, 2012 %!#%##"%!"%  % %!%!#%##"% ""%$$$ • • • • • • • Built-in simulator Program Do-more with the completely new - and FREE - Do-more Designer software. (DirectSOFT and ladder programs More program memory More and flexible data type memory Faster program execution Easier-to-use instruction set Integrated Ethernet on the CPU Faster I/O for counting and motion applications More and easier-to-use communications developed with DirectSOFT are not compatible with these CPUs. ) Download the FREE software! Get started fast! Choose a Do-more starter kit to get going fast. You get: $$$% % % % The new Do-more H2 series CPUs leverage the existing line of DL205 I/O modules and base units to create an incredibly powerful PLC - at an incredible bargain. 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And each Do-more CPU comes with a coupon for a 30-day free trial of online video training. 1-800-633-0405 RS# 103 DEPARTMENTS ON THE COVER Photo by R.L.Rubenking 8 EDITORIAL More green cards, more H-1B visas 10 EDITORIAL STAFF 12 LETTERS 16 SCANNING FOR IDEAS Liquid cooling for servers also supplies hot water Gimbal mount expands drones’ view 20 REPORTER’S NOTEBOOK 26 LOOKING BACK 33 SENSOR SENSE Metal-faced inductive sensors for durability 35 COMMENTARY Google’s got nothing on Cat 36 INVENTOR’S CORNER Compact engine packs a powerful punch 68 PRODUCT SPOTLIGHT Linear actuators 72 PRODUCTS 74 BUSINESS INDEX 76 STATEMENT OF OWNERSHIP 77 AD INDEX 78 CLASSIFIEDS 78 BUSINESS STAFF 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. 79 BACKTALK 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. 4 MACHINE DESIGN.com NOVEMBER 8, 2012 POSTMASTER: Send change of address notice to Customer Service, MACHINE DESIGN, P.O. Box 2100, Skokie, IL 60076-7800. EXAIR Blows Away The Competition! S e Over Save Ov r $1,200 P r Year Y r 200 Per R p i g One O Outdated O d d Air Nozzle! By Replacing We’ve all seen flat air nozzles. Some are yellow. Others are orange. The oldest ones are blue or metal. Those other manufacturers want you to believe you’ll save money by conserving compressed air while protecting your workers from harmful noise levels. In reality, those colorful air nozzles that blow the air out of holes consume enormous amounts of air. The plastic ones often break off. Some might even get you an OSHA fine due to the dangerous dead ended pressures that exist if someone blocks the air exhaust. EXAIR’s award winning 2" Super Air Nozzle™ has been engineered to replace those outdated flat nozzles. There are no dangerous holes. EXAIR’s patented, award winning design is efficient, maintaining a precise amount of airflow through a thin slot. The result is a forceful stream of high velocity, laminar airflow with minimal air consumption and noise. You can increase or decrease the force of each flat air nozzle – using shims to tune it to the application so you’ll never waste compressed air. Flat nozzles from other manufacturers can consume over 30 SCFM (a refrigerator sized compressor) and aren’t adjustable. Some manufacturers offer different flow rates but you need to guess at which one will do the job since you can’t adjust them once you’ve made the purchase. By default, most users feel bigger is better and go with the highest flow rate, wasting compressed air. COMPARE Here’s how: • One popular flat nozzle consumes 31 SCFM @ 80 PSIG. • EXAIR’s 2" Super Air Nozzle with .015" shim consumes 21.8 SCFM @ 80 PSIG. • 31 SCFM (theirs) – 21.8 SCFM (EXAIR’s) = 9.2 SCFM compressed air saved/min. Most large plants know their cost per 1,000 standard cubic feet of compressed air. If you don’t know your actual cost per 1,000 SCF, 25¢ is a reasonable average to use. • SCFM saved x 60 minutes x cost/1,000 SCF = dollars saved per hour. • In this case, 9.2 SCFM x 60 x .25/1,000 SCF= 13.8 cents saved per hour. • 13.8 cents per hour x 24 hours = $3.31 saved per day. • $3.31 per day x 365 days = $1,208.88 saved in one year (in this 24/7 operation). And, This Savings Is For One Nozzle! Air Nozzle Yellow Air Consumption Noise Level lbs. of Force @ 80 PSIG dBA @ 80 PSIG 29 SCFM 83 1.7 Orange 28 SCFM 82 1.7 Blue 26 SCFM 78 1.5 Metal (machined) 29 SCFM 82 1.7 Metal (cast) 31 SCFM EXAIR 2" Super Air Nozzle *7.3- 30 SCFM 80 1.9 62-81 0.5 – 1.9 *Air consumption dependent upon shim size. EXAIR’s 2" Super Air Nozzle can pay for itself in less than 15 days. Put the 2" Super Air Nozzle to work in your blowoff, cooling or drying application. We’re sure you’ll agree that it blows away the competition! RS# 104 11510 Goldcoast Drive • Cincinnati, OH 45249-1621 Phone (800) 903-9247 • FAX (513) 671-3363 E-mail: [email protected] www.exair.com/45/42san.htm @EXAIR The Guarantee What’s new online machinedesign.com FREE EBOOK Vibrations in designs incorporating gears: Sources, analysis, and solutions All moving machinery generates vibration — which, in turn, wastes energy, degrades movement accuracy, and eventually leads to system failure. This eBook, sponsored by Stober Drives, explains how careful vibration analysis reveals information that can be used to troubleshoot root machinery problems. That helps keep electric motors, couplings, gearboxes, bearings, and other components up and running. Download a free copy at http://machinedesign.com/ebook. Power everything via USB The president of the USB Implementers Forum gives an overview of the new USB power-delivery standard, and how it could eliminate the custom power cords and bricks so many devices require. It uses heavier cables, handles up to 20 V and 100 W, and can dynamically convert a device from a consumer to provider of power without changing the cable. Learn more at www. engineeringtv.com/video/PowerEverything-Via-USB-IDF-20;OnlyEngineering-TV-Videos. EDITOR’S WEB PICKS Roller and conveyor chains 6 A new 140-page catalog from iwis drive systems covers the design, selection, and application of a wide range of chains. Content includes roller, conveyor, accumulation, flyer, and flat-top chains, maintenancefree and corrosion-resistant versions, modular belts for industrial applications, and products for timing drives. There’s also a section on lubricants and lubrication methods. Request or download a copy at www. iwis.de/catalogues. Power-supply site Mouser Electronics has launched a new Power Supply site. It contains technical and design information, including the benefits of switchedmode power supplies such as high efficiency, small size, and light weight. It also provides details on UPS and ac/dc applications. Content includes product data, white papers, a library of technical resources, and info on products from major manufacturers. Visit www.mouser. com/power-supply-technology. Dealing with digital The Agilent Technologies HighSpeed Digital site (www.agilent. MACHINE DESIGN.com com/find/HSD) covers test and measurement products such as oscilloscopes, analyzers, and meters. It delves into topics such as signal integrity, design and simulation, and high-speed digital analysis, and offers debugging tips. The technical support area includes a library, FAQs, and discussion forums. And a new white paper, “Crossing the Digital-Analog Divide,” explains how digital signals are idealized at high data rates, as well as how to cope with the physical nature of signals that engineers might prefer to think of as bits and bytes. Bearings info Kilian Manufacturing, an Altra Industrial Motion company, has a new Web site on bearings and assemblies for demanding automotive and industrial applications. It covers products such as ball, needle, roller, and thrust bearings, as well as customengineered specialty bearings and polymer assemblies. Content included downloadable brochures, catalogs, industry specific application profiles, service manuals, and articles. Visit www.KilianBearings. com. NOVEMBER 8, 2012 UPCOMING WEB EVENTS BASICS OF MOTION CONTROL WITH PLCs AND STEPPERS Online tutorial videos detail motion-control theory and application using PLCs as the supervisory controller. A new 11-part Motion Control video series features the DirectLogic 05 PLC, SureStep stepping system components, and C-more micro HMI. It starts with the basics of the hardware, describes typical motion applications, then moves through demonstrations using equipment such as a linear slide. To view individual segments of this series, visit http://learn. automationdirect.com and look under the Drives/Motors tab. Four new Do-more PLC videos focus on using the new CPU with the latest high-speed counter module to perform motion applications using switches or encoders, as well as details on hardware setup and software functions such as trapezoidal moves. To view this series, visit http:// learn.automationdirect.com and look under the PLCs tab for Domore PLC-Live demos. Or find them all at: www.youtube. com/automationdirect. Become a subscriber and get alerts when new videos are uploaded. &XVWRP$LU3URGXFWV 30° S AU T XH   V OVHDO HUDWXUHV D L F H S S V JKWHP IRUKL  ULGJH OFDUW UDWLRQ D L F H S X V FRQILJ VW\OH 25  QHHG GD\ \HVWHU G DSSOLH XEH 3)3(O ODWHG HOS 3 .81QLFN 5 RJJOH 1 . 2OW VWH1H  If you need a quality valve, cylinder or fitting but off-the-shelf catalog models don’t quite fit the bill, just call us. Clippard can provide just what you are looking for. Tell us your needs . . . we have solutions! FUHDWH VROXWLRQV Providing innovative products and solutions for today’s engineering challenges   ,QVWUXPHQW/DE,QF__¬ZZZFOLSSDUGFRP Miniature Pneumatic Air Cylinders, Electronic Valves, Control Valves, Acrylic Subplates, Air Preparation Eqt., Fittings, Hose and More RS# 106 EDITORIAL More green cards, more H-1B visas Microsoft was recently in the news because it came up with a new scheme for more H-1B visas. H-1B, of course, lets U. S. companies employ foreign workers in such highly specialized occupations as science, technology, engineering, and mathematics (STEM). Microsoft not only wants Congress to permit more H-1B visas but also to reallocate 20,000 green cards for workers with such technical skills. In return for boosting H-1B quotas, Microsoft would have Uncle Sam charge companies $10,000 per additional H-1B worker. It also suggests charging employers $15,000 per STEM green card over the current quota. So far, so good. Employers should be willing to pay a stiff fee if they feel their needs are urgent enough to hire outside the U. S. I’d even suggest setting the fee at levels far higher than what Microsoft has in mind as a way of making employers show they are serious. But interestingly enough, Microsoft also wants fees collected from greencard permits to be invested in STEM education. Microsoft claims such measures are necessary because it has 3,400 open jobs for scientists and engineers while the U. S. last year minted only 1,603 new computer science Ph.Ds. Of course, industry has for decades leveled allegations of shortages as a rationale for letting more foreign skilled workers enter the U. S. But researchers at the Bureau of Labor Statistics have studied the impact of letting in foreign Ph.Ds. and concluded that the result is a downward pressure on Ph.D. salaries. This downward pressure tends to discourage aspiring scientists from pursuing higher degrees. The result: The smartest of them go where the money is, which, today, is still in finance. There, new financial engineers can still earn six-figure bonuses in the first year on the job. Thus, Microsoft’s idea for new H-1B fees seems self-defeating. The education it funds would create more workers in areas now being filled by foreigners. But filling jobs with foreign workers reduces pay scales and makes jobs in that area less attractive. One might be excused for seeing this whole process as a negative feedback loop for the process of minting STEM Ph.Ds. in the U. S. So here is an off-the-wall idea for what to do with U. S. STEM graduates in an era when STEM jobs get filled by foreign workers: make it easy for U. S. technical personnel to become Canadians. Workers with easy access to our Northern neighbor would have more options if salary levels take a hit from an influx of foreign workers. And indications are that Canada might be open to this idea. “The Government of Canada is committed to building an immigration system that actively recruits talent,” said a Canadian minister recently. “This is the next frontier in Canadian immigration: looking at opportunities to attract the best talent and going out there and getting it,” he continued. A representative of the Canadian government even went to Ireland a few months ago to beg STEM graduates there to try living in Canada. The labor situation for STEM workers in Canada is so tight that its government officials are entertaining the idea of instituting special benefits for Canadian STEM personnel willing to work past the age of 65 — not because they lack the money to retire, but because they are so difficult to replace. One other point in Canada’s favor: There’s no out-of-control financial sector in that country run by individuals making obscene salaries. — Leland Teschler, Editor RS# 107 NOVEMBER 8, 2012 Listen to the difference. Our fans for cooling and refrigeration technology are already among the quietest and most efficient in the world. How can we top that? Easily: with the new AxiTop diffuser. It optimizes air flow at the impeller exhaust, significantly increasing efficiency. This means up to 7.2 dB(A) of noise reduction and up to 27% lower energy consumption at the same flow rate for your refrigeration application. Or up to 9 % more air performance with comparable energy consumption! If this sounds like music to your ears, visit info.ebmpapst.us/AxiTop for more information. the engineer’s choice RS# 108 Moving Assembly Lines for the Heaviest Products EDITORIAL STAFF Powered by Proven, Versatile Air Film Technology EDITOR Leland E. Teschler [email protected] MANAGING EDITOR Kenneth J. Korane [email protected] SENIOR EDITORS ` -PX$BQJUBM*OWFTUNFOU ` &MJNJOBUF$SBOFTBOE'PSL5SVDLT ` &OIBODF4BGFUZBOE1SPEVDUJWJUZ 800-888-0018 XXXBJSGMPBUDPN "JS#FBSJOH&RVJQNFOUt-JGU5JMU5BCMFTt5VSOUBCMFTt"TTFNCMZ-JOFT &SHPOPNJD&RVJQNFOUt5SBOTQPSUFSTt3JHHJOH&RVJQNFOU RS# 109 Leslie Gordon [email protected] Stephen J. Mraz [email protected] ASSOCIATE EDITORS Lindsey Frick [email protected] Robert J. Repas, Jr. [email protected] INDUSTRY COVERAGE: AUTOMOTIVE, PACKAGING, MEDICAL Stephen J. Mraz CAD/CAM, MANUFACTURING Leslie Gordon ELECTRICAL, ELECTRONICS Robert J. Repas, Jr. FASTENING & JOINING, MATERIALS Lindsey Frick FLUID POWER Kenneth J. Korane MECHANICAL Lindsey Frick Kenneth J. Korane EDITORIAL PRODUCTION Denise Greco Editorial Production Manager Randall L. Rubenking Art Director 1300 E. 9th St. Cleveland, OH 44114-1503 10 MACHINE DESIGN.com RS# 110 NOVEMBER 8, 2012 ƵƚŽŵĂƟŽŶĞƋƵŝƉŵĞŶƚƌĞƋƵŝƌĞƐŝŶŶŽǀĂƟǀĞƐŽůƵƟŽŶƐĨŽƌŵŽǀŝŶŐƉŽǁĞƌĂŶĚĚĂƚĂ ĂĐƌŽƐƐƌŽƚĂƟŶŐŝŶƚĞƌĨĂĐĞƐ"DŽŽŐŽīĞƌƐŽǀĞƌϭϬ,ϬϬϬƐůŝƉƌŝŶŐĚĞƐŝŐŶƐ"DŽĚĞůƐ ĂƌĞĂǀĂŝůĂďůĞŝŶĐĂƉƐƵůĞ,ƚŚƌŽƵŐŚďŽƌĞĂŶĚĮďĞƌŽƉƟĐĐŽŶĮŐƵƌĂƟŽŶƐ" ZĞůŝĂďŝůŝƚLJŝƐďƵŝůƚŝŶƚŽĞĂĐŚƉƌŽĚƵĐƚ"džƚĞŶƐŝǀĞůŝĨĞƚĞƐƟŶŐŵĞĂŶƐŽƵƌƐůŝƉ ƌŝŶŐƐĂƌĞĚĞƐŝŐŶĞĚĂŶĚŵĂŶƵĨĂĐƚƵƌĞĚƚŽŽīĞƌůŽŶŐůŝĨĞĂŶĚůĞƐƐĚŽǁŶƟŵĞ" >ĞĂƌŶŵŽƌĞĂďŽƵƚDŽŽŐ/ƐƐŽůƵƟŽŶƐĨŽƌĂƵƚŽŵĂƟŽŶĂŶĚƌŽďŽƟĐƐ"^ƚĂŶĚĂƌĚƐůŝƉ ƌŝŶŐĚĞƐŝŐŶƐĂƌĞƌĞĂĚLJĨŽƌƋƵŝĐŬĚĞůŝǀĞƌLJŽƌĐĂŶďĞƚĂŝůŽƌĞĚĨŽƌƵŶŝƋƵĞƉƌŽũĞĐƚƐ" ŽŶƚĂĐƚƵƐƚŽĚŝƐĐƵƐƐLJŽƵƌĂƉƉůŝĐĂƟŽŶ"   >ŽŽŬŝŶŐĨŽƌŵŽƌĞ  ^ĐĂŶƚŽǀŝĞǁƐůŝƉƌŝŶŐƐƉĞĐŝĮĐĂƟŽŶƐ ^ůŝƉZŝŶŐ&ĞĂƚƵƌĞƐ 3 3 3 3 3  DŽƟŽŶdĞĐŚŶŽůŽŐLJ &ŝďĞƌKƉƟĐƐ ůĞĐƚƌŽŶŝĐ^LJƐƚĞŵƐ нϭϱϰϬϱϱϮϯϬϭϭဒϬϬϯϯϲϮϭϭϮ;h^ ŵĐŐΛŵŽŽŐ"ĐŽŵ ǁǁǁŵŽŽŐĐŽŵĐŽŵƉŽŶĞŶƚƐ RS# 111 ŽŶƟŶƵŽƵƐϯϲϬΣƌŽƚĂƟŽŶ ŽŵƉĂĐƚƐŝnjĞ DĂŝŶƚĞŶĂŶĐĞĨƌĞĞŽƉĞƌĂƟŽŶ ZŽďƵƐƚƉĞƌĨŽƌŵĂŶĐĞ ŽŵƉĂƟďůĞǁŝƚŚĚĂƚĂ ďƵƐƉƌŽƚŽĐŽůƐ LETTERS Don’t tread on Tennessee Stop dissin’ Tennessee After I read a letter to the editor (“Everyone Loves LA,” Sept. 6), I knew that I would have to comment. The reader says that the reason that only 42% of Nissan’s workforce relocated to Franklin, Tenn., is because people don’t want to live in secondrate locations. I’m not sure what he means by this, but it is obvious he has never been to Franklin and probably doesn’t know it is a suburb of Nashville. Franklin has consistently been rated in the top cities in the country to live based on cost of living, education, quality of life, and other factors. In fact, quite a number of large corporations are located in or near Nashville, and many have their headquarters in the Nashville area. These include companies like Mars Petcare, Caterpillar Financial, Bridgestone/Firestone, Louisiana Pacific, Caremark, and Asurian. It’s also home to Nissan’s Smyrna plant and General Motors’ Spring Hill plant. And although many of these companies do not necessarily have a lot of engineers located in Middle Tennessee, they understand that the quality of life for their employees, the low cost of living and tax rates, and access to a highly educated workforce make it a great place to set up shop. (There are 18 institutions of higher education in Middle Tennessee.) In addition, middle Tennessee is within 650 miles of over 150 million people. And by the way, I was born and raised in the Detroit area and couldn’t wait to leave. I didn’t consider it a first rate place to live. And as far as LA is concerned, you couldn’t pay me enough to live there. Jim Johnson Making snide remarks about Tennessee is not helpful. We are all in this together, and when people talk like that about the heartland, they only increase the resentment felt by Midwestern conservatives. They are already mad enough at the rest of us. And as far as the comment that 12 MACHINE DESIGN.com Many readers volunteered to stick up for Tennessee against an earlier letter writer who didn’t seem to have too high an opinion of that southern state. Another reader bemoans the small print in his employment agreement. no high-tech work gets done in Tennessee, that’s where the Manhattan Project was carried out. By the way, I live in New Jersey, a part of the country that gets almost as much abuse as the south. Dudley M. Jones I would advise the reader who didn’t like Tennessee that if he doesn’t already live in California, then please do the rest of us a favor and move there. To insinuate that “smart people don’t want to be anywhere but California” shows just how ignorant you are. And please don’t try to imply that all engineers share your opinion. I believe Nissan is on the right track by relocating. They will probably attract a substantial amount of engineering talent that would be much happier in Tennessee (both on and off the job) than in the freak show called California. Cadiero Gregg To paraphrase my mother, if you can’t say something nice about a state, don’t say anything at all. — Editor They’re stifling me, and you Most scientists, engineers, and technical employees who have jobs don’t control their creative brains anymore. Their employers do. For example, I developed a new farm product in my own basement shop that was totally unrelated to my day job in the defense industry. My employer claimed my invention based on the fine print in the NOVEMBER 8, 2012 crippling “Employee Agreement” I had signed earlier as a condition of employment. He didn’t even want the invention. He just wanted to crush any inkling of outside entrepreneurship arising from any of his employees. No wonder we are stuck with millions unemployed despite adding $3 billion to the national debt every day. We need a federal “Use or Return” law to restore creative incentives and protection intended by our Founding Fathers when they established the U. S. Patent Office back in 1790. It might give American employees the creative freedom necessary to create the new business and private-sector jobs we so urgently need. Robert Nepper It has been my experience after working with manufacturers all over the world, that U. S. has the best and most-creative engineering talent in the world. Our biggest problem is that our management does not understand or accept this talent. Most engineering talent is not recognized but, in fact, repressed, is because it would involve company politics. The head of a large manufacturing company once commented to me, “We have been doing it our way for 50 years, so why would we change?” I’ve also heard: “We tried something 30 years ago and it didn’t work.” What they really mean is that many manufacturing companies want to run production the same way they’ve always run it. And they expect engineers to RS# 112 LETTERS keep fixing old equipment when it clearly is no longer fixable. It seems there’s always that one guy in the big corner office that doesn’t want to evolve and is just waiting it out until retirement. But that same guy will hound every employee for better production rates, less maintenance issues, and so on. The last thing he wants is to invest in new equipment to run leaner and smarter production through modern engineering ideas and technology. After all, he might make a mistake. Paul Pfundtner Bring on the TechShops I do hope this TechShop effort prospers and spreads (“Manufacturing for the Masses,” Sept. 6). There use to be a business called MonkeyWrench, which rented out tool shops to do-it-yourself auto repairmen (and women). But the business didn’t do as well as I had hoped. One set of reasons for the lack of success was the increasing difficulty of working on cars and trucks for those not trained to deal with the computerization of today’s vehicles, the need for electronic-analysis equipment, and densely packed engine compartments in almost all new cars. I presume and hope that TechShops will not run into similar problems. I would love to see them become commonplace. In my humble opinion, the business deserves public funding and support. If we are to be a more innovative country, this kind of facility ought to help. From personal experience, I know that getting parts from machine shops is not easy or inexpensive. With the small budget most inventors have, this kind of resource could be a real boon to me and people like me. Mark Stapelton LETTERS TO THE EDITOR Please include your name, address, and daytime phone number. Letters may be edited for brevity and to focus on essential points. Mail: Letters, MACHINE DESIGN, 1300 E. 9th St., Cleveland, OH 441141503, Fax: 216-621-8469 E-mail, Editorial: [email protected] Corrections: Acquisitions — The Lord Corp., Cary, N. C., is purchasing MicroStrain Inc., Williston, Vt. (“Company News,” Oct. 4). B-2 Bomber — The fine news item on UAVs (“More competition for carrier-based UAVs,” Sept. 20) has a small but notable error. Northrop Grumman is the designer and developer of the B-2 Spirit, not Boeing. Jack Fagan Make the Switch. Literally. It’s time for a change. So make the switch to Nason and say goodbye to switches that almost work. With Nason, you’ll get exactly what you want when you create your own quality bi-metal temperature switch. And once you make the perfect combination, we’ll send you a free sample, so you’ll know before you order that it fits your application to a T. Make your own switch using the widest range of electrical connections in the industry. .com NOVEMBER 8, 2012 Check out our TT switches online and see how easy making the switch can be. http://nasonptc.com/ttswitch RS# 113 MACHINE DESIGN.com Don’t forget to request your own sample: http://nasonptc.com/switch_form 800.229.4955 • www.nasonptc.com Watch “Making the Switch” on YouTube. www.youtube.com/NasonPTC 14 Each switch is preset and 100% are tested— a feature unique to Nason. Make the switch to Nason, and make yourself a perfect switch. Solutions for Automation That Take You Straight to the Top Unrivaled in scope and versatility, Schaeffler’s linear product line ranges from shafts with linear ball bearings and monorail guidance systems to sophisticated actuators with drives and control systems, plus special coatings and every conceivable accessory. You name it, we’ve got it. But that’s only the start. Our linear portfolio is based on a modular concept that goes far beyond mere components. We can design a complete system solution tailored to your specific application - from large gantry robots to intricate circuit board inspection systems. In fact, many of our linear guidance systems started out as solutions to customers’ needs! Class dismissed. Superior-quality products. Comprehensive reliable solutions. www.schaeffler.us ©2012 RS# 114 SCANNING FOR IDEAS Edited by Stephen J. Mraz Liquid cooling for servers also supplies hot water Heated coolant exits at top of rack The CarnotJet from Green Revolution Cooling, Austin (grcooling.com), uses a liquid coolant to remove heat from CarnotJet data-center servers, rack including highdensity and blade servers. The coolant is a nonproprietary odorless, white mineral oil which was chosen for its clarity, low viscosity, high flash point, and high specific heat capacity. To ensure servers can survive submersion in the coolant, GRC removes the fans and encapsulates the hard drives. Also, servers typically use thermal grease to help heat sinks remove heat. In the CarnotJet, it Coolant gets replaced with a pump covering of indium, a soft metal foil with high-heat conductivity. Coolant is pumped through a heat exchanger, where it gives up its heat to a Coolant-to-water stream of water. A pump module heat exchanger containing variable-speed, digitally controlled pumps and heat exchangers can handle the thermal demands of up to four racks of servers. And the coolant should last 10 years or more, roughly the life of the system. Using this equipment instead of an arsenal of chassis and power-supply fans cuts a server’s energy use by 5 to 25% and reduces the amount of energy used for cooling by 90 to 95%. It also lets the servers be packaged in a smaller enclosure. The closed-loop liquid cooling and pump are also significantly quieter than the fans they replace. And water comes out of the heat exchanger at 122°F and can be sent to an evaporative cooler or serve as a source of hot waste for a secondary purpose such as heating nearby buildings. RS# 401 16 MACHINE DESIGN.com NOVEMBER 8, 2012 Servers vertically installed in coolant bath Evaporative cooling tower releases heat to the atmosphere r formation via ou Request free in Web site at Reader Service c design.com/rs ww w.machine Our plotters are the fastest in their class. THE NEW EPSON SURECOLOR T-SERIES ® ® • Capable of producing a precise, color, D-sized plot in 25 seconds • Extreme plotting accuracy at resolutions up to 2880 x 1440 dpi • Advanced pigment ink technology for truly durable, full-color plots • High-capacity ink cartridges up to 700 mL for low printing cost • Space-saving design with easy access front-loading paper and ink EPSON SureColor T3000 - 24" | $2,995 EPSON SureColor T5000 - 36" | $3,995 EPSON SureColor T7000 - 44" | $4,995 6SHHGVDUHEDVHGXSRQSULQWHQJLQHVSHHGRQO\7RWDOWKURXJKSXWWLPHVGHSHQGXSRQIDFWRUVVXFKDVFRPSXWHUILOHVL]HSULQWHUUHVROXWLRQLQNFRYHUDJHDQGQHWZRUNLQJ)RUWKH6&7WRSVSHHGIRUD'VL]HGSORWLVVHFRQGV 3ULFHVDUH0653EHIRUHUHEDWHV3OHDVHFKHFNZLWKDQ(36213URIHVVLRQDO,PDJLQJ$XWKRUL]HG5HVHOOHUIRUDFWXDOSULFHDVGHDOHUSULFHVPD\YDU\ (3621DQG6XUH&RORUDUHUHJLVWHUHGWUDGHPDUNVDQG(3621([FHHGdd,K^ĂŵŽŶŐŽƚŚĞƌƐƚŚŝŶŐƐ  *HDUKREELQJDQGJHDUJULQGLQJIURPμ²μ $*0$  ,QWHUQDOJHDUJULQGLQJIURPμ²μ &1&JHDULQVSHFWLRQXSWRμ *HDUVKDSLQJWRμLQGLDPHWHUμIDFHZLGWK 'HVLJQDQG$QDO\VLV H[FHOOHQWVRIWZDUHFRP  5HYHUVHHQJLQHHULQJVHUYLFH :LQGWXUELQHJHDUER[KLJKVSHHGVSLQGOHVJLPEDOKHDGV DQGJHDUER[HV 18 MACHINE DESIGN.com NOVEMBER 8, 2012 RS# 116
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