I am presently working on a job where we have to qualify some welders to a new procedure, it is written into their procedure that no grinding is allowed on the welder performance qualification coupon! It is my belief that this is an unacceptable way to do things, a welder should be allowed to use the tools to weld his coupon the same as he would in the field. Opinions? Thanks Steve in Cincinnati
I respectfully disagree with you for most tests. I feel that a performance test is intended to determine if a welder can combine weld parameters, technique, and bead placement to make an acceptable weld. Under actual work conditions, a welder can and should use tools and grinders to make good welds, especially since you rarely will have perfect conditions to weld under. A weld test however is conducted with consistant joint fit-up and clean metal and the person usually is allowed to make him/herself comfortable. If grinding is allowed, what are you actually testing?
An exception would be non-standard situations where the welders are highly skilled as proven by testing and experience, but the welds might be in an "impossible" location (or something similar). In that case, you would really be training for the difficult task because the welder already knows how to "lay in a good bead".
Interestingly, D1.5 disallows use of anything but hand tools in performance testing but D1.1 doesn't say you can't grind. I'm not sure what other codes allow.
CHGuilford
I respectfully agree with CHG. Performance qualification should duplicate anticipated conditions encountered during production welding (shop or field). I also believe this is the reason for the limitations set forth in AWS D1.5-95, 5.21.5(1-3).
My thoughts are that if a welder is welding a coupon in the overhead or 6G positions and he puts in a little weld overlap he has to be able to grind that out before installing his next pass. I am not saying that it would be acceptable for a welder to spend three days grinding out every pass that he puts in, but not allowing a welder to prep the previous pass in order to be able to weld the next pass without a fusion problem does not make sense to me! Granted this welder would have to be the one making this decision not the inspector. What would a welder be expected to do if he encounters this situation? Should we expect him to weld over an unacceptable condition and hope to burn it in or should he just give up. I think that the test is designed to test the ability of a welder to install sound welds and that includes the ability to know when and where he needs to prep the previous pass. Lets face it even in a perfect enviroment we cannot expect a welder to be able to weld an overhead or 6G coupon without the use of a grinder. I would like to hear more opinions on this subject. thanks Steve in Cincinnati
Hello there--I have had this argument "discussion" with the Production Manager where I work. He actually cited an opinion by the AWS D1.1 technical commitee that said "D1.1 does not prohibit the use of power tools to qualify a welder performance test." I guess they figure that a Weldor applying for a Job will use the same criteria that I use when inspecting a finished weld---or inter-pass conditions that I observe.Yeah---right! I welded for 25+ years before I became a CWI-----Many places would lock up the grinders after you prepped the test joint.I still say--either you can weld--or you can't. If you are a Weldor, you should be able to meet Code requirements without touching-up your WPQR test plate. But as A CWI, I am sworn to uphold whaterver Code I am inspecting to.
This opinion is in the "Official Interpretations of D1.1" Like I said---I disagree---but I can Weld!
T.H.Stephen
Our company position is that we limit the time for a performance test and restrict the use of a grinder. If the welder makes a small mistake, he/she may request the use of a grinder to correct the error. The test administator decides, after inspection, whether or not to allow the use of a grinder. It is a "welding test" not a "grinding test".
Furthermore, in addition to the criteria specified in D1.1, we limit openings (on bend coupons) to no more than five (regardless of how small they are).
We are not interested in welders that can just barely pass a test. We demand a higher degree of talent. Even with our standards, we still have to periodically send some of our welders back to the shop for brush up training. Charles Hall
WHAT TYPE TEST ARE WE DISCUSSING ? IS IT AN OPEN BUTT V-GROOVE WITH 100% PENETRATION? WHAT PROCESS? SMAW,GMAW, GTAW,SAW. WHAT POSITION 3-G, 4-G, IF PIPE 2,5,OR 6G. WHAT IS THE DIRECTION OF TRAVEL- UP OR DOWN. WHAT ELECTRODE OR ELECTRODES ARE BEING USED? I TOO CAN WELD BUT SOME TEST REQUIRE DIFFERENT THINGS. TRY TO USE GOOD JUDGEMENT . IF YOU CAN WELD YOU WILL BE RIGHT. HOWEVER , YOU DO NEED TO FOLLOW THE PROCEEDURE.
A blanket statement of "no grinders" without consideration for the process, test assembly configuration, filler metal etc. is strong evidence of an organization that isn't familar with or have respect for the welding processes and the people performing them.
I would like to see an individual perform a qualification test on say 4" sch 80 inconel with SMAW and a backing ring. Or a restricted position mirror welded 1" carbon steel socket weld.
The ability to prove by "certification" the skills and value of a welder are very limited I think. I think a time limit would be more appropriate. With no allowance for starching your new carharrt shirt,polishing your belt buckle made on the last job in the test shop, sanding the copper of er-70 wire, talking to other welders about how youv'e never had a bad shot, and all those other things I've seen.
If a test is properly supervised with an experienced welder (not a guy that is a CWI and never welded) then the person doing the supervision can make an accurate judgement of the welders abilities. I've been suprised on many occasions of the performance on the job compared to the performance in the test shop.
How about asking a fitter to tell me the takeout of a 23 degree 2" Long radius elbow without a calculator. Or maybe burn me a bevel on a 6" pipe and only clean it up with a file!
Also note that if you are qualifying welders to a "procedure" then you are doing extra. Welders are qualified within variables for the welders qualification. If your production requires no use of grinders then maybe its a good idea. If you wrote a procedure procedure for testing welders without the use of grinders then see above.
Have a good day all.
Gerald Austin
http://www.weldinginspectionsvcs.com/
I'd have to agree with pipewelder_1999 on this one.
How should I feather my tacks? With a file? I think not.
The proper use of a grinder is as much a skill as is welding. How many times have I seen the result of improper grinding, looking more like the pipe or plate was attacked with a chainsaw.
I think a more appropriate question is what are they grinding? Starts and stops? Or are they "ringing" the pipe to remove undercut, and the slag trapped in it?
I think the "no grinding" approach readily lends itself to the "I'll burn it out" approach. If people are "burning it out" on a test coupon, what are they "burning out" in the field? Cracks maybe? It might be more accurate to ask, "what is it that you have buried?".
And what about specimen selection from a coupon? Shouldn't it be a random thing, instead of 2, 4, 8, and 10 o'clock? I think the incorporation of starts and stops into the bend specimen would be a good indication of one's abilities as a welder. One could leave a bunch of porosity and slag in a coupon at the 6 oclock position on a 6G, 6" sch 160 test, and still pass with flying colors.
Dale Simonds
Dale, FYI, the applicable code specifies where to cut the specimens from (relative to the top on pipe, and measured from the ends on plate). In my opinion that is sufficient. My experience, which as you know is limited to inspection, is that a good visual on the pipe ID reveals unacceptable indications which are associated with feathering tacks. You can also see fish eyes caused by impatient break off of the arc at stop points very clearly. See you saturday. charles hall
I believe any of us who are both skilled and competent welders and inspectors can make the correct call when it comes to administering a welder qualification test. Being both a skilled code qualified welder and experienced CWI/CWE, I appreciate the skills required to produce a bend quality weld. Most of us with this combination of experience recognizes the difference between necessary grinding of the test coupon and excessive grinding. I want my welder, whether qualifying for a test or welding in production, to use the appropriate tools when he/she deems necessary. I assure you, as you gain experience in administering welder qualification tests you learn to recognize the difference in workmanship, experience and pride of the welder.
I am just curious! Could that have read "No Back Grinding permitted" ?
By SteveB
Date 11-29-2001 16:46
no
After seeing all the responses so far I see the potential for a lively discussion. Good view points from all. I also see that I failed to fully qualify my first comment. I do not have a pipe welding background having worked most of my career in structural steel and bridges, so my thoughts were from that arena. What I should have said is I do not agree with allowing grinding on structural plate tests and fillet weld tests as a "normal" part of the testing. I have no objection to grinding on pipe or square tube tests if overseen by a qualified test administrator. In the past I have allowed a small amount of grinding for something that was not the welder's fault, such as a faulty wire feeder or somebody tripping over a cable or etc. Also, some people don't hold up well under the pressure of a test but are talented welders otherwise. I might allow limited grinding in that case as long as I can see that the problem was not from lack of skills.
Overall though I don't like to allow grinding on plate tests because everything is in a straight line, there are no tacks in the way (or shouldn't be), the welder can sit in a lawn chair if he/she wants to, and those tests are all about bead placement and control, not about grinding. If qualifying to D1.5, I don't allow any grinding because it's not allowed and I have to sign the forms. I will allow a welder to start over with new plates if, again, the problem was not lack of skills.
I have no sympathy for grinding on a fillet weld test. Those tests are usually treatedwith disdain by most welders yet my experience has been that about 50% of experienced welders will not get fusion to the root in the horizontal position on the first try. The novices usually do better which "humbles" the others. Considering that 95% of the welds made on structural steel are fillets and those should be the easiest welds to make I don't feel this is unreasonable. I do make sure that I'm not being judge, jury and executioner about it all.
Again, I don't work with pipe so I leave that to those who do.
CHGuilford
