Welding Journal | December 2014

PUBLISHED BY THE AMERICAN WELDING SOCIETY TO ADVANCE THE SCIENCE, TECHNOLOGY, AND APPLICATION OF WELDINGAND ALLIED JOINING AND CUTTING PROCESSES WORLDWIDE, INCLUDING BRAZING, SOLDERING, AND THERMAL SPRAYING

December 2014

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40 Improving GMAW Efficiency through Shielding Gases Practical recommendations are made to improve welding operations through the use of argon-based shielding gases — D. Sarma

46 A Technology to Increase SAW Productivity The use of an electrically isolated welding wire helps to increase deposition rates in submerged arc welding — H. Raudsepp

48 A Must in Today’s Workplace: WeldQuality Monitoring Point-of-use monitoring and postweld verification are two methods for improving weld quality M. Albright

DECEMBER 2014 / WELDING JOURNAL 3

CONTENTS

80 Heat Tint Poses Corrosion Hazard in Stainless Steel Advice is given on ways to eliminate heat tint when welding stainless steel — M. Fletcher

84 Welding Program Revitalized A welding program is reborn and a dedicated teacher inspires his students to look to the future as welders — A. Cullison

88 Considerations for Selecting Shop Grinders The author evaluates different types of grinder power sources and suggests which is best A. H. Krieg

THE AMERICAN WELDER

443s Characterization of Multilayered Multipass Friction Stir Weld on ASTM A572 G50 Steel A butt/lap joint configuration was friction stir welded and its mechanical properties were evaluated for the best welds — Y. C. Lim et al.

451s Friction Stir Welding of Extruded Powder Metallurgy Al Allloy It was demonstrated that friction stir welding produced joints without voids or discontinuities and a refined microstructure in the stir zone — A. Elrefaey et al.

458s Low Transformation Temperature Welding Consumables for Residual Stress Management:

A Numerical Model for the Prediction of Phase TransformationInduced Compressive Residual Stresses Numerical analysis using the software Sysweld was performed on gas metal arc welds made with low- transformation-temperature welding wires T. Alghamdi and S. Liu

472s Improvement of Process Robustness in Weld Bonding of Galvanized DP780 Steel A variable electrode force was used in this study to widen the weld lobe — Y. S. Zhang et al.

WELDING RESEARCH SUPPLEMENT

December 2014 • Volume 93 • Number 12

FEATURES

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6 Editorial8 Washington Watchword10 Press Time News12 International Update16 News of the Industry22 Business Briefs24 Letters to the Editor26 Brazing Q&A28 Aluminum Q&A34 Product & Print Spotlight52 Coming Events56 Certification Schedule

59 Society News60 Tech Topics61 Errata D1.2/D1.2M:2014

Amendment Notice75 Guide to AWS Services78 Personnel

The American Welder 90 Learning Track94 Fact Sheet96 Welding Journal Index112 Classifieds114 Advertiser Index

OFFICERSPresident Dean R. WilsonWelldean Enterprises

Vice President David J. LandonVermeer Mfg. Co.

Vice President David L. McQuaidD. L. McQuaid and Associates, Inc.

Vice President John R. BrayAffiliated Machinery, Inc.

Treasurer Robert G. PaliJ. P. Nissen Co.

Executive Director Ray W. ShookAmerican Welding Society

DIRECTORSU. Aschemeier (Dist. 7), Subsea Global SolutionsR. E. Brenner (Dist. 10), CnD Industries, Inc.D. J. Burgess (Dist. 8), Alstom PowerN. C. Cole (Past President), NCC EngineeringG. Fairbanks (Dist. 9), Fairbanks Inspection &

Testing ServicesT. A. Ferri (Dist. 1), Victor TechnologiesK. Fogleman (Dist. 16), ConsultantP. H. Gorman (Dist. 20), Sandia National LaboratoriesS. A. Harris (Dist. 4), Altec IndustriesK. L. Johnson (Dist. 19), Vigor ShipyardsJ. Jones (At Large), The Harris Products GroupJ. Knapp (Dist. 17), Gas and SupplyT. J. Lienert (At Large), Los Alamos National LaboratoryD. E. Lynnes (Dist. 15), Lynnes Welding TrainingC. Matricardi (Dist. 5), Welding Solutions, Inc.S. P. Moran (At Large), Weir American HydroK. A. Phy (Dist. 6), K. A. Phy Services, Inc.W. R. Polanin (At Large), Illinois Central CollegeW. A. Rice (Past President), OKI BeringR. L. Richwine (Dist. 14), Ivy Tech State CollegeD. J. Roland (Dist. 12), Airgas USA, LLC,

NorthCentral Region

R. W. Roth (At Large), RoMan Manufacturing, Inc.N. Saminich (Dist. 21), NS Inspection and ConsultingK. E. Shatell (Dist. 22), Pacific Gas & Electric Co.T. A. Siewert (At Large), NIST (ret.)J. Stoll (Dist. 18), Bohler Welding Group U.S.H. W. Thompson (Dist. 2), UL, Inc.R. P. Wilcox (Dist. 11), Ford Motor Co.J. A. Willard (Dist. 13), Kankakee Community CollegeM. R. Wiswesser (Dist. 3), Welder Training &

Testing Institute

WELDING JOURNALPublisher — Andrew CullisonEditorialEditorial Director Andrew CullisonEditor Mary Ruth JohnsenAssociate Editor Howard M. WoodwardAssociate Editor Kristin CampbellEditorial Asst./Peer Review Coor. Melissa GomezPublisher Emeritus Jeff Weber

Design and ProductionProduction Manager Zaida ChavezSr. Production Coordinator Brenda FloresManager of International Periodicals andElectronic Media Carlos Guzman

AdvertisingNational Sales Director Rob SaltzsteinSr. Advertising Sales Exec. Sandra JorgensenSr. Advertising Sales Exec. Annette DelagrangeManager of Sales Operations Lea PanecaSr. Advertising Production Manager Frank Wilson

SubscriptionsSubscriptions Representative Tabetha [email protected]

PUBLICATIONS, EXPOSITIONS, MARKETING COMMITTEED. L. Doench, Chair, Hobart Brothers Co.S. Bartholomew, Vice Chair, ESAB Welding

& Cutting Prod.J. D. Weber, Secretary, American Welding SocietyD. Brown, Weiler BrushT. Coco, Victor Technologies International

C. Coffey, Lincoln ElectricD. DeCorte, RoMan Mfg.S. Fyffe, Astaras, Inc.D. Levin, AirgasR. Madden, HyperthermD. Marquard, IBEDA SuperflashJ. F. Saenger Jr., ConsultantS. Smith, WeldAid ProductsD. Wilson, Welldean EnterprisesJ. N. DuPont, Ex Off., Lehigh UniversityL. G. Kvidahl, Ex Off., Northrop Grumman

Ship SystemsD. J. Landon, Ex Off., Vermeer Mfg.S. P. Moran, Ex Off., Weir American HydroE. Norman, Ex Off., Southwest Area Career CenterR. G. Pali, Ex Off., J. P. Nissen Co.N. Scotchmer, Ex Off., Huys IndustriesR. W. Shook, Ex Off., American Welding Society

American Welding Society8669 NW 36 St., # 130, Miami, FL 331666672(305) 4439353 or (800) 4439353

On the cover: A welding operator oversees asubmerged arc tandem welding applicationin which two twin wire heads are placed insequence to achieve wire deposition rates ofup to 83.7 lb/h. (Photo courtesy of ESABWelding & Cutting Equipment, Florence, S.C.)

Welding Journal (ISSN 00432296) is published monthly bythe American Welding Society for $120.00 per year in the UnitedStates and possessions, $160 per year in foreign countries: $7.50per single issue for domestic AWS members and $10.00 per singleissue for nonmembers and $14.00 single issue for international.American Welding Society is located at 8669 NW 36th St., # 130,Miami, FL 331666672; telephone (305) 4439353. Periodicalspostage paid in Miami, Fla., and additional mailing offices. POSTMASTER: Send address changes to Welding Journal, 8669 NW36th St., # 130, Miami, FL 331666672. Canada Post: PublicationsMail Agreement #40612608 Canada Returns to be sent toBleuchip International, P.O. Box 25542, London, ON N6C 6B2,Canada.

Readers of Welding Journal may make copies of articles forpersonal, archival, educational or research purposes, and whichare not for sale or resale. Permission is granted to quote from articles, provided customary acknowledgment of authors and sourcesis made. Starred (*) items excluded from copyright.

Copyright © 2014 by American Welding Society in bothprinted and electronic formats. The Society is not responsible forany statement made or opinion expressed herein. Data and information developed by the authors of specific articles are for informational purposes only and are not intended for use without independent, substantiating investigation on the part of potential users.

DEPARTMENTS

WELDING JOURNAL / DECEMBER 20144

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When I took office as president of theAmerican Welding Society just a year ago, Iunveiled my theme of “continuous improve-ment through innovation.” As it turned out,2014 was a year of remarkable innovation atAWS. Today, I thank the entire Society — its70,000-plus members, more than 1000committee members, Board of Directors,160 Sections, 38 international agents, in-dustry partners, hundreds of scholarshipdonors, and 130 dedicated staff members —for coming through with so many innova-tions that are making history for our mis-sion “to advance the science, technology,and application of welding and allied joiningand cutting processes.” While that’s the So-ciety’s historic mission, this year we infor-mally expanded it to “advancing the peopleof welding.” By all measures, 2014 has been a greatyear for AWS and its mission. We surpassedall our financial goals and we are surpassingour nonfinancial goals, as well. Even more significantly, we have set thestage for elevating AWS up to a much higherlevel, with an impressive list of innovationsand improvements. As president, I kept youinformed through a series of video updateson our progress for the first time ever. Continuous improvement through inno-vation has been demonstrated in the salesand marketing areas, with a brand-newbranding strategy, complete with an updat-ed logo, a soon-to-be unveiled new website,and a reorganized sales force that is activearound the world. We have launched an AWS Asia office inChina, with three AWS employees there.That gives us a brick-and-mortar presencein Hong Kong and Beijing. And our recentinternational agency meeting at our beauti-ful headquarters demonstrated expandedrelationships with dozens of educationaland industry partners from 17 countries. It’s all about the people of welding. Weintroduced an AWS customer satisfactionsurvey that gives us new metrics to work to-ward to exceed member expectations. Following are just a few of what AWS hasaccomplished this year: The value of the research content in thisWelding Journal has more than tripled since2008, according to the standard academic

measurement of research impact. The recent FABTECH expo in Atlantawas the biggest ever held outside of Chica-go. And next year’s Chicago show has al-ready broken all records for exhibitor spacereservations. This year, hundreds of Certified WeldingInspector candidates benefited from newonline training from AWS Learning, prepar-ing them better than ever before for liveseminars, examination, and, ultimately,their new professional responsibilities. One of my priorities has been the fulfill-ment of a Master Welder credential. We wantto recognize those special welders who workto perfect their craft. This year, more than10,000 stakeholders were surveyed to provideguidance for a blue-ribbon task group that isdeveloping the Master Welder program. Continuous improvement requires greatstaff and a strong technology infrastruc-ture. A new chief information officer, EmilioDel Riego, is leading a multimillion-dollarmodernization of AWS’s IT system and webtechnology. With all these improvements in place,AWS is poised to launch the most signifi-cant innovation of all. The Society has de-voted a year to advancing the people ofwelding, with new career managementtools, including stackable credentials, class-room and online training, and secure, effi-cient placement for qualified jobseekers.Our goal is to provide welding professionalswith continuous career enhancement toolsfrom recruitment to retirement. This will be a game-changer in howwelders are hired, how they obtain valuableskills and credentials, and how they will beempowered to perform better and earnmore over their careers. Next month is the launch date for thisamazing innovation. Whether you are anemployer, an employee, a student, or an ed-ucator, you need to be ready to activate yourprofile on this powerful and secure system.This represents a revolution in how we workin our industry, and it’s a superb demon-stration of what we can gain from continu-ous improvement through innovation. Again, I thank everyone in the AWS fami-ly around the world for a very successfulyear of advancing the science, technology,application, and people of welding.

EDITORIAL

AWS Continues to Innovate


Dean R. WilsonAWS President

“This will be agamechanger inhow welders arehired, how they obtain valuable skillsand credentials,and how they willbe empowered toperform better andearn more overtheir lifetime.”

WJ

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Editorial Profile

For those engaged inwelding-related activities,Welding Journal providescurrent news, features,research reports, practical data, and advertisementsfrom industry leaders aroundthe world. Also featured arewelding-related metalworkingactivities such as design,testing and inspection,maintenance and repair, and training.

Other EditorialFeatures of Welding Journal

• News of the Industry• New Products • New Literature• Aluminum Q&A• Welding Workbook• Washington Watchword• Brazing Q&A• Peer-Reviewed

Welding Research• Book Reviews• Press Time News• Society News • Personnel• Editorial• Coming Events• International Update• Resistance Welding Q&A• Business Briefs

Welding Journal is the official monthly publication of the American Welding Society.About 69,000 AWS members depend on it every month for news of products,technology, and people in the welding/metalworking industry. This planner providesadvertising rates for Welding Journal, Inspection Trends, Welding Marketplace, theWelding Journal en Español, the AWS website, and FABTECH advertising.

EditorialDeadline

January

February

March

May

June

July

August

September

October

November

December

• FABTECH Recap Nov. 21, 2014 Dec. 1, 2014• Shielded Metal Arc Welding Update

• Resistance Welding Dec. 19, 2014 Jan. 5, 2015• Understanding Heat Treatment• Bonus: The American Welder

• Brazing & Soldering Today Jan. 23 Feb. 2• Fabricating Machinery for Cold

Environments

• Today’s Welding Education and Training Feb. 20 Mar. 2• Choosing the Right Filler Metals and

Electrodes

• Shipbuilding Developments Mar. 20 Apr. 6• Bonus: The American Welder

• Pipe & Tube Apr. 20 May 4• How Metal Composition Affects Weldability• Challenges Welding Engineers Face

• Job Challenges Welders Face May 22 June 1• What’s New in Robot Technology

• Thermal Spray Update June 19 July 6• Welding Guns and Torches• Bonus: The American Welder

• Employment Issues in the Welding Industry July 20 Aug. 3• Allied Processes: Bending and Forming • Cutting Update

• 2015 FABTECH Preview Aug. 21 Sept. 7

• Safety & Health• Brazing & Soldering Today Sept. 21 Oct. 5• Weld Inspection

• Welding in the Power Industry Oct. 23 Nov. 2• Tips for Small Businesses• Bonus: The American Welder

April

WELDING JOURNAL 2015 EDITORIAL CALENDAR

AdvertisingDeadline

AdvertisingBonus

Welding SchoolProfiles

Thermal SprayCompanyProfiles

Red Hotsfor Safety

ReadershipSurvey

BonusDistribution atFABTECH

Brazing CompanyProfilesBonus Distributionat IBSC

Bonus Distributionat GAWDA SpringConference

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When Joe Williams graduatedfrom the welding class atPhiladelphia’s A. Philip Ran-

dolph Career and Technical HighSchool in 1986, little did he think thathe would come back to his old class-room and sit at his teacher’s desk, nolonger a student, but the instructorrunning the program. Like many weld-ing programs in the last 20 years, itfell into disfavor and faded away.

Many school districts looked on weld-ing as dirty, expensive, and not a verygood career path. The program becamedormant until 2012 when Williamswas hired to revive it.

Fateful Call

Since his graduation, Williams nev-er had a hard time finding a weldingjob. He’s worked in oil refineries, gov-

erment jobs, shipyards, and even onthe production set of Avatar: The LastAirbender. “I was always getting callsfor welding jobs,” he said. “One day, Ithought ‘if there is this great need forwelders, who is teaching all thesewelders who are needed?’” Thatthought motivated him to call thePhiladelphia school district and in-quire whether there were any weldingjobs open. He got a positive response


Welding Program RevitalizedA long-dormant welding program is givennew life, and inner-city students are ontrack for a future in welding

BY ANDREW CULLISON

THE AMERICAN WELDERTHE AMERICAN WELDER

Fig. 1 — Instructor Joe Williams and his welding class.

Cullison 12-14_Layout 1 11/11/14 2:50 PM Page 84

and immediately sent in his résumé.Within 30 days, he was approved andsigned up as the instructor who wouldgive a rebirth to the welding program.

Diverse StudentPopulation

A. Philip Randolph Career andTechnical High School is a city-wideschool servicing a diverse group of stu-dents from across Philadelphia. “In ad-dition to core academics, it offers nineprograms of study, one of which iswelding,” said Williams. “My studentslearn all facets of the welding tradefrom reading blueprints to processeslike shielded metal arc, gas metal arc,and flux cored arc welding.” Students who attend the highschool have to apply for admission. Itis a magnet school that is not restrict-ed by neighborhood boundaries andaccepts students from across the city.

Admission is competitive. “Initially, the welding program wasnot very popular and was consideredby the students not to be as ‘glam-orous’ as other programs,” saidWilliams. He exposed those initialclasses to the many opportunities thatwelding careers provide, but it washard to get them hooked when theequipment they were using to practicetheir skills dated back to whenWilliams was a student. That problemwas solved when a helping hand wasoffered from Airgas, Radnor, Pa.

Partnership Jump Starts Program

Ron Stark, senior vice president ofsales and marketing for Airgas, camein contact with Darryl Overton, princi-pal of A. Philip Randolph High School,who was passionate about restartingthe welding program. “Airgas thought

a partnership with the school would bea good fit to help fulfill the futureneed for welders,” said Stark. “It alsopresented a good social outreach for usand its close proximity to our head-quarters were favorable factors, butwhat sealed the deal was meeting Mr.Williams,” said Stark. “He was enthusi-astic and dedicated to the program.” The deal involved providing newequipment and accessories for thewelding lab. Through a partnershipwith Miller Electric Co., Appleton,Wis., Airgas was able to provide newMiller welding machines and relatedproducts. “Now the students couldperfect their skills on state-of-the-artequipment,” said Williams. “Withthese industry collaborations, wordquickly spread through the school andthe community, and the welding pro-gram became the school’s premier of-fering,” he continued. “This year, ourenrollment in the welding class hasdoubled from last year.”


THE AMERICAN WELDER

Fig. 2 — A student welding an Amnesty Box for the Philadelphia school district.

Cullison 12-14_Layout 1 11/10/14 11:13 AM Page 85

More than Equipment

The industry collaboration with Air-gas wasn’t limited to just providingequipment. Dave Schaffer, a weldingprocess specialist, provided his expert-ise to what was needed to get the pro-gram into the 21st century. Dan Ske-han, director of automation, was avail-able to offer advice, and Eric Smith, adistrict manager in Airgas East region,has been involved since 2013, and sitson the school’s Occupational AdvisoryCommittee. They provided additionalhelp by getting donations of scrap, pro-viding setup and training on the newequipment, and organizing field tripsto various industries. “Airgas personnelremain active in helping the program.Recently, the City of Philadelphia andits school district, along with represen-tatives from Airgas, held a celebrationin the welding work area. “Airgas pro-vides not only resources, but also men-torship,” said Williams. “Their peoplealways take time to speak to my stu-dents, drop off products, and giveworkshops,” he continued.

Student Interest Grows

Williams presently has 45 studentsin his class — Fig. 1. “Many studentswere initially enrolled in other pro-grams before transferring over to thewelding program,” said Williams.“However, they made sacrifices andtook risks to join my program andlearn unfamiliar skills about an unfa-miliar trade and industry,” he contin-ued. “Many of my students also makedaily sacrifices to learn their craft, in-cluding staying after school and forgo-ing their lunch to have extra time.They understand the long-term bene-fits and give up much of their in-school socializing to dedicate them-selves to welding,” said Williams. Many students come from unstablehome environments. “If not for theschool-provided breakfast, some maynot eat on a regular basis,” saidWilliams. “Welding helps them focustheir energy and attention beyondtheir current situation and into the fu-ture. I am very proud of the growthand pride my students have for theircraft, but most importantly in them-selves.” “I found out I am not just a teacher,but a mentor,” he said. “I have had let-

ters from parents thanking me be-cause they no longer have problemsgetting their child to school. Theywant to go to welding class,” saidWilliams. “I think I was meant to be ateacher; it has changed my life.”

Recognition

Williams’ class has gained recogni-tion through the local newspaper andTV media. Recently, his class was com-missioned by the School District ofPhiladelphia to design and fabricate(Fig. 2) Amnesty Boxes. These all-welded boxes (Fig. 3) are located out-side persistently dangerous schools forstudents to anonymously dispose of il-legal contraband, such as drugs andweapons, with no questions asked. “My students and I are very proudto be part of this program to reduce vi-olence,” said Williams.

First Graduating Class

This year will see the first graduat-ing class for 11 seniors. Williams has100% placement for all the graduates.They will be starting jobs with variouslocal industries earning $12–16 to be-gin. Three of his students already hadfull-time jobs lined up with PTR BalerCompacter, where they had been serv-ing internships. “I constantly receivecalls from companies in dire need ofwelders.” As long as Williams contin-ues to inspire his students to do theirbest, he will be able to meet thoseneeds.


THE AMERICAN WELDER

WJ

ANDREW CULLISON is publisher, Welding Journal

Fig. 3 — A finished Amnesty Box designed and fabricated by Williams’ students.

Cullison 12-14_Layout 1 11/10/14 11:13 AM Page 86

Grinding in metal fabrication isone of the most expensive andtime-consuming operations.

There are, however, many ways thatthe fabricator can save time, effort,and money to reduce the prohibitivecost of grinding. While there are alter-native means to grinding, includingweld preparation bevelers, and othertools, this article is strictly related togrinding. The first consideration of a fabrica-tor who employs many people ingrinding operations is what sort ofpower tool, i.e., grinder, should theybe using. The first considerations arethe volume of work and the number ofemployees who use grinding. If theshop has more than five grinding sta-tions, considerable savings can be real-ized. There are several decisions to bemade.

Grinder Power Sources The market in power tools is huge,but for specialty applications it ismuch smaller than the common toolmarket. For powering grinders, thereare the following five types of motorscurrently available:

• Universal 110-V, 60-Hz, single-phase electric motor• Pneumatic (air-driven) motor• Three-phase (squirrel cage) induc-tion motor • Hydraulic (oil-liquid-driven)• High-frequency, 300- to 360-Hzelectric squirrel cage motors.

Other Cost Factors In grinding operations, the issuesof paramount importance are mainte-nance costs, power-to-weight ratio,horsepower, speed (rev/min), totaltool weight, and noise. All of these can impact operator fa-tigue, which in grinding is an impor-tant factor. While the grinding wheelmakeup, binder, and grit size are alsoimportant, this article assumes all areoptimized for the task in question. Each of the five motor types hascertain advantages and shortcomingsas follows: The universal 110-V, 60-Hz electricmotors have these advantages. Theycan be used most any place, are easily

moved from job to job, and offer rela-tively good power-to-weight ratio.However, they have the highest main-tenance costs, and are heavier thansome other options. The pneumatically driven motorscommonly used industrially tend to benoisy, have poorer power-to-weight ra-tios, are expensive in power consump-tion, require frequent service, and donot operate at constant speeds. The squirrel cage three-phase in-duction motors are heavy and moredifficult to handle. Hydraulic motors, while excellentfor some power tool applications, arenot suited to grinding operations atall. Since the high-frequency or high-


Considerations for SelectingShop GrindersDetailed are five grinder toolpower sources and the author’srecommendations to shop owners

BY ADRIAN H. KRIEG

THE AMERICAN WELDERTHE AMERICAN WELDER

American Welder feature2_Layout 1 11/10/14 11:26 AM Page 88

cycle tools are not commonly used, anexplanation is required. The three-phase, 60-Hz induction motors oper-ate at 3600 rev/min. This speed is nothigh enough for industrial grindingoperations, which normally require aspeed of 16,000 surface ft/min. Note:This is the optimum speed of a grind-ing wheel at the point of contact,which is approximately the speed of a22-caliber bullet. High-frequency toolsoperate at multiples of the line fre-quency, which in the United States is60 Hz. The multiples of 60 Hz are 60,120, 180, 240, 300, 360, etc. The 120and 180 Hz are too low, resulting inmotor speeds of only 7200 and 10,800rev/min, respectively. The optimumspeed for such a motor is from 18,000to 21,600 rev/min. All commercial air-craft engines use 400-Hz motors dueto weight and the fact they are not tiedto a 60-Hz original power source, theyoperate at about 25,000 rev/min. Air-craft motor information is mentionedhere to provide proof that the power-to-weight ratios and reliability forhigh-frequency tools are far and awaythe best for all power tools.

Comparing Two PowerSources for Best Operation The two most desirable power toolgrinding methods therefore requiresecondary power sources. Pneumatictools require a compressor, in mostcases, a screw compressor; and high-frequency tools require a frequencyconverter. In both cases, there is appli-cable electric switchgear in environ-mentally and economically sound ap-plications. Note the star-delta motorstarter switches use less power whenstarting. These two comparative means ofdriving the power tool in question re-quires us to consider their individualcharacteristics. Air-driven tools have very poorability to maintain constant speed. Airtool manufacturers try to compensatefor this using a motor-speed governor,which complicates the motor design,but is absolutely necessary from asafety perspective. Without a gover-nor, an excessive increase in air-linepressure could cause the motor to spintoo fast causing the grinding wheel to

explode. For this reason, all air motorsused in grinding applications havebuilt-in governors. Another drawbackis air tools are very noisy. The motorexhaust noise is often louder than thegrinding noise. Consider also that airmotors have very poor power curves.As the load increases, the rev/min rap-idly fall. Bear in mind that if optimumspeed (rev/min) of the grinding wheelis not maintained, the output falls.And lastly, air tools are heavy andclumsy compared to modern high-frequency tools. The high-frequency-powered toolsare by far the most satisfactory forgrinding operations. The reasons areas follows: They offer the best weight-to-power output, lowest weight-to-power ratio, highest rev/min, and low-est maintenance requirements. In ad-dition, they offer the lowest noise out-put and most favorable operator ac-ceptance. In shipbuilding, foundries,and heavy fabrication where morethan ten grinders are employed, thecost reductions and improved workoutput can pay for the equipment inless than 12 months. It may be worthwhile to investigatethe cost to upgrade the equipment inyour shop. Start by getting quotesfrom the high-frequency tool manu-facturers, which include Bosch, Fein,AEG, and CP. The frequency convert-ers are available from GE, Westing-house, and Himmelwerke. Theswitchgear products are sold by SquareD and most electrical switchgear man-ufacturers. Because the grinding speed is close-ly related to wheel consumption it isimportant to keep the grinding edge ofthe wheel running at the optimum16,000 surface speed per second(SFPS). To maintain this speed, theuser should purchase grinders withdifferent operating speeds. For exam-ple, for angle grinders, the most com-monly used grinder, purchase toolsrated at 6000 and 8500 rev/min, and9-in.-diameter wheels. As the wheelwears down to under 7 in. in diameter,switch to the higher speed grinder tomaintain 16,000 SFPS constant speedat point of contact and get the bestpossible output.


THE AMERICAN WELDER

WJ

DR. ADRIAN H. KRIEG, CMFGE ([email protected]) is anAWS Life Member. He is with A2Z Publications LLC, Bradenton, Fla.

WORK SMART

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At R & S Welding Mentors LLC,Salem, Ore., instruction is targeted totraining students for good-paying jobsin the structural steel, fabrication, andproduction industries that are currentlyavailable in the Pacific Northwestregion. The school offers both hands-onperformance-based training and AWSwelding certification training andtesting with special stress on workplacesafety, and the skills necessary fordeveloping teamwork, and good workethics.

Mission Statement R & S Welding Mentors’ mission isto deliver specialized training for indi-viduals eager to learn welding and fab-rication skills for the 21st century. Itsgoal is to help young people, displacedworkers, and others receive the best inclass welding skills, knowledge, andworkforce competencies, to enablethem to secure high-paying jobs andadd value to the organizations theywork for, while achieving their person-

al professional goals. The facility is a Private CareerSchool licensed by the Oregon’s HigherEducation Coordination Commission.Students first complete safety trainingthen receive instruction on setting upwelding machines for various consum-ables and welding parameters. Stu-dents have the opportunity to beginwelding on their first day. The standards of the AmericanWelding Society are referencedthroughout the course material and


R & S Welding Mentors Offers Small Classes and Personalized Instruction

Experienced instructors share their expertise to trainstudents for goodpaying jobs in the Pacific Northwest HOWARD M. WOODWARD

([email protected]) is associate editor of the Welding Journal.

LEARNING TRACK

BY HOWARD M. WOODWARD

THE AMERICAN WELDER

R & S Welding Mentors LLC management and teaching staff members are (from left) CWI Tom Welch, Instructors Tony Kummer and MilanPond, Owner James Stanton, Business Manager Koneta Stanton, Administrator Collette Myers, and CWI BJ Hutchins. All photos by BarryHutchins Photography, Salem, Ore.

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the certification process. As part of the students’ training inproper welding procedures, their in-structors supplement their educationswith their personal experiences in thefield and pass on some tricks of thetrade based on their real world knowl-edge of a cross section of the weldingindustry. Most beginning students practicethe shielded metal arc (SMA) weldingprocess first before advancing to learn-ing the gas metal arc (GMA) and/orflux core arc (FCA) welding processes.Students then are offered the opportu-nity to learn either or both gas tung-sten arc (GTA) and pipe welding pre-sented as advanced courses. Uponcompletion of instruction in theseprocesses, students can schedule a cer-tification test at the school with CWIBJ Hutchins of IQA (Inspection Quali-ty Assurance).

Small Class Sizes Students benefit from the school’ssmall class sizes featuring a 6-to-1 student-instructor ratio. This provideseach student a lot of one-on-one at-tention and enables trainees with noprevious welding experience to achievein just 15 weeks all the skills and con-fidence necessary to succeed in an entry-level position. Graduates of the basic courses maychoose to continue their studies to be-come more proficient and learn addi-

tional welding processes. School owner James W. Stantonsaid, “We teach SMA, FCA, GMA, andGTA welding processes on mild steel,stainless steel, and aluminum. In addi-tion, students learn torch cutting,plasma cutting, and carbon arc, includ-ing setting the parameters and safetyaspect for each process. “Our training is performance-based. Each student is enabled tomove forward at his or her own pacedetermined by their ability to learnand to meet the welding standards. Wetry to keep each student challengedand excited about moving forward. Wealso strive to help students under-stand the value of good work ethicsand the value of relating to coworkersand being a team player.” Stanton noted that he has receivedcalls from a number of former stu-dents telling him how they have pro-gressed in their careers in the weldingindustry. Hearing from them as theyreceive raises and promotions over theyears and become financially self-suffi-cient is very rewarding. “We encourage previous students toschedule a day in the welding labwhenever they have an interviewscheduled for a welding job,” he added.They can spend a day refreshing theirskills so they can be better preparedfor taking an employer’s weld test.This opportunity is offered free of

charge to all students who have com-pleted the 15-week program.

Additional Services Stanton said, “While a majority ofour students seek instruction to pur-sue a career in welding, we also wel-come students who want to weld forhobby or home repairs. Private tutor-ing is also offered. Occasionally, awelder may purchase a machine forpersonal use then ask us to help set itup and show them how to make thebest use of their new equipment. Wecan provide an instructor to help themcorrectly assemble and determine theparameters for its proper use.

Enrollment Welding can be a demanding trade,so before being accepted for trainingeach student is interviewed to deter-mine whether this training would beappropriate for them, and to deter-mine what level of training is needed. Applicants must be at least 18 yearsold, pass a drug test, be healthyenough to work an 8-h shift in allweather conditions, have the ability tolift at least 45 lb, work at times witharms elevated, have 20/20 vision, andpossess the spatial and mechanicalperceptions required to safely performthe work. This interview may also in-


THE AMERICAN WELDER

Peter Frey practices his weld tackingtechnique under James Stanton’s watchful eye.

James Stanton (left) and CWI BJ Hutchins prepare an outdoor welding project to givethe students some simulated field experience.


clude a skill assessment should the ap-plicant have welding experience. Stanton said, “We strive to helpeach student set appropriate goals fortheir long-term career plans. Under-standing each student’s goals in thewelding industry helps us tailor theirtraining on an individual basis. Thisenables each student to be more suc-cessful in his or her pursuit of employ-ment in the welding industry.

The Facility The R & S Welding Mentors facilityis equipped with 14 individual weldingbooths with the latest state-of-the-artequipment. In addition, a number ofolder welding machines is maintainedon site to familiarize students with theearlier technology they may encounterwhile working in the field. The equip-ment training is occasionally supple-mented by demonstrations presentedby Ron Gross, district manager forMiller Electric who details the Dynasty350, and Les Nelson, district businessmanager for Victor Technologies, whodisplays the newest products in theTweeco line.

The Instructors School owner James W. Stanton hasan extensive background in the weld-ing industry. He discovered his pas-sion for welding during junior high

school, continued welding trainingthrough high school, and graduatedwith the skills to secure a journeymanwelder position. He worked in manydifferent aspects of the industry in-cluding production welding, as a jour-neyman shipwright, manufacturing,crane operator/certified welder inbridge construction, and undergroundboring including pipe welding. Duringhis work in the industry, Stanton en-joyed teaching coworkers the art ofwelding and fabrication. He is passion-ate about teaching and helping stu-dents overcome barriers while devel-oping their strengths. “Welding,” hesaid, “is in my genes, being that I amthe great-grandson of the famousblacksmith Walter Stanton of theCharles Goodnight Ranch.” Tom Welch, a Senior CertifiedWelding Inspector (SCWI) and a con-sultant for IMR KHA Portland TestLabs and Steel Quality Specialists,shares his extensive experience andknowledge of the welding industry tostudents in his classes. Milan Pond, a full time instructor,is passionate about teaching and help-ing students overcome barriers whiledeveloping their strengths. Pond is ex-perienced in the building construction,automotive welding, fabrication, andornamental ironwork industries. Tony Kummer recently joined thestaff as a part-time instructor. Kum-mer is a highly skilled GTA welder who

effectively shares his enthusiasm forthe welding trades with his classes.

Community Impact Mari McGovern, a job developerand training specialist at Careers NW,said, “As a job developer for the Ore-gon Vocational Rehabilitation Servicesprogram, I have seen several of myclients successfully complete weldingcertificates of every kind at R&S Weld-ing Mentors. Because my clients faceserious barriers to employment, fromphysical and learning disabilities tohomelessness and felonies, just toname a few, James Stanton and Busi-ness Manager Koneta Stanton mentorfar beyond simply teaching them weld-ing skills. They use a nonjudgmental,gentle yet firm approach with them,taking into consideration the weldingstudent’s underlying struggles andbackground to teach them both thevocational and life skills necessary tobecome a successful, contributingteam member. As a result, many of thecompanies I work with recruit theirwelding candidates directly throughR&S.” Graduate welding student HeatherClark agreed the instructors are help-ful, encouraging, and consistent everyday. Their interaction with students iswith the utmost respect and patience.She especially liked the emphasis ontime allocated to welding in the booth,which for her was the best way to de-velop the skills she needed to acquirethe various certifications.

R & S Welding Mentors LLCContact

Koneta StantonBusiness Manager

1750 Oxford St. SE, Salem, OR 97302 Phone: (503) 884-3277

e-mail; [email protected]


THE AMERICAN WELDER

Practicing some team cooperation are (from left) Instructor Milan Pond, student TravisSuek, and CWI BJ Hutchins.

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High-quality welds with fewer weld defects than otherprocesses can be produced with submerged arc welding(SAW) because of the excellent protection of the weld metalby the blanket of molten slag. As in other processes, howev-er, the problems of porosity, slag inclusions, incomplete fu-sion, and cracking occur in SAW. Following are some causesand remedies for the problems.

Porosity Weld metal deposited with the SAW process is usually cleanand free of harmful porosity, but when porosity does occur, itmay be found on the weld bead surface or beneath a soundsurface. As with other welding processes, the base metal andelectrode must be clean and dry in SAW. High travel speedsand associated fast weld metal solidification do not providetime for gas to escape from the molten weld metal. The travelspeed can be reduced, but other solutions should be investigat-ed to avoid higher welding costs. Porosity from covered elec-trode tack welds can be avoided by using electrodes that leaveno porosity-causing residue. Recommended tack weld elec-trodes are E6010, E6011, E7015, E7016, and E7018.

Inclusions An inclusion in a weld is defined as the entrapment ofsolid foreign material such as slag, flux, or oxide. If notproperly applied, SAW is not immune to slag inclusions. In-clusions are primarily found in the root overlap or betweenprevious passes, and generally near bevel faces or groovefaces. The risk of inclusions is greater under the followingconditions: 1) In downhill orientations, which may allow the moltenflux to race ahead of the weld pool and then roll under to be-come entrapped during solidification; 2) In grooves along the edges of previously depositedbeads, especially if they are convex; 3) If there is undercut along the edges of the weld bead; 4) When arc destabilization inhibits the slag from risingto the top of the solidifying weld pool; 5) When a flux too high in viscosity is used, impeding thesolidification of the weld pool; 6) When a clean prior bead surface is not maintained; 7) In the case of improper welding head displacement,particularly in the downhill orientation; 8) In the case of reduced penetration due to reduced heatinput, supplemental wires or powders, increased electrodeextension, excessive travel speed, or reduced arc density; 9) In the case of excessive travel speed, which causesfaster cooling and may inhibit the slag from rising to the topof the weld pool.

Incomplete Fusion Incomplete fusion can occur at any depth of the weld. Itcan occur between either the present or previous beads orthe bead and the bevel or groove faces. Specific conditions,most of which inhibit the melting and the fusible contactbetween surfaces, may foster incomplete fusion. These con-ditions include the following: 1) Incorrect joint preparation or procedure 2) Presence of slag or oxide residue 3) Arc instability 4) High travel speeds 5) Insufficient heat input 6) Improper displacement, angle, or position of the weld-ing head.

Cracking Weldment cracking is considered the most serious of dis-continuities because of the potential for catastrophic servicefailure and the often-experienced difficulty in radiographicinspection. Cracking can be categorized according to severalcriteria, including location [weld metal, heat-affected zone,or base metal cracking (hot or cold cracking)], but it is gen-erally assumed to have two causes — an imposed strain andan inability to accommodate that strain.

Hot and Cold Cracking The types of hot cracking include solidification, liquation,and stress-relief cracking. This discontinuity is usually asso-ciated with the weld metal. Several conditions associatedwith strains and the ability to accommodate them, predomi-nantly of cross-sectional geometry and chemistry, follow: 1) Excess depth-to-width ratio 2) Excessive concavity (inability to accommodate strains),especially with fillet welds 3) Inadequate fill at weld bead stopping points (decreasesability to accommodate strain), which can cause cratercracks 4) Chemical contamination, especially from sulfur or hydrocarbon-bearing compounds. Excessive heat input may decrease the cooling rate andincrease the time for metallurgical reactions in a crack-susceptible temperature range. Like hot cracking, cold cracking manifests itself in a num-ber of ways. These include hydrogen-induced cracking orstress-corrosion cracking. Most cold cracking is associatedwith the heat-affected zone, base metal, or weld metal.

THE AMERICAN WELDER


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Quality Considerations for Submerged Arc Welding

FACT SHEET

Excerpted from the Welding Handbook, 9th Edition, Volume 2, Welding Processes, Part 1.

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general corporate_FP_TEMP 11/10/14 8:27 AM Page 93

Documents

Welding Journal | December 2014