Welder Qualification 2

[rick44028]

If I wanted to qualify a welder for 1" thru 8" diameter pipe with W.T. ranges of 0.188" to 0.500"
What size diameter and wall thickness of pipe will accomplish this, or do I need to make more than one weld on another size pipe to cover that range.

 

[Seldom]

Hi Rick44028,
If you're using ASME Sec IX, make sure your test coupons are equal to or larger then 1" NPS and the wall thickness is at least .250" Seldom
"There's no such thing as a welding problem, there are only welding puzzles of assorted sizes!"

 

[moseley]

Seldom,
I am sure he is not going to find a 1" diameter pipe .250" wt, what do you think? My suggestion to get to his diameters and his thickness is to perform 2 tests (which every welder is custom to). First to get his 1" diam. and .188 thickness would be to use a 2" sch 40 cs pipe GTAW all the way with 2 face and 2 root bends. Then he could test to a 6" sch 40 (.280 wall) to get his .500" WT. Rick I hope this helps. The tests above except for the modification on the WT for the 6", are a standard test that all welders perform. At least in the petroleum field. Also I forgot to mention that the 6" need the same tests performed. Hope this helps

 

[Seldom]

Hi moseley,
I understand what you're saying and I might be a little rusty on Sec IX but am I not correct in the answer to his question? He didn't ask how to test his welders, he asked-
"to qualify a welder for 1" thru 8" diameter pipe with W.T. ranges of 0.188" to 0.500"

He didn't ask what would be the easiest or best diameter to test with nor did he give any indication as to what process(s) he was using to perform them or what materials he had on hand to used as coupons. I would believe he was looking for some accurate, but general info rather then precise because of not noting his particular circumstances or conditions.

If he had asked for advice as to which diameter, regardless of process he should use , I would have advised him to use either 11/2 or 2" sch 160 if he can get it. One set of tests with unlimited diameter qualifications over 3/4" NPS (1" OD) and wall thickness limitations to 688". I realize in some industries the 6" test is standard but not necessarily in the chemical, possibly because of the variety of smaller pipe sizes used. If he can't get the heavy wall then he'll have to do something similar to your suggestion.

With your scenerio I believe he has to take at least two different sets of qualification tests just because of the 6" diameter test restriction of 2 1/2" NPS. On top of it all, it's common knowledge that the skill level to successfully pass a qualification test goes up as test coupon diameter goes down. The old excuse I've heard a lot over the years about welders using 6" coupons was that they use more filler to that must means they have more opportunity for error. Sure you use more filler to do the 6" and it is only an excuse in my opinion because there's not the twist of the wrist you need to successfully complete a 2" or similar diameter test with the 6". In addition, with the smaller diameters, radiography is preferred rather then strapping and bending, which from my experience is far and away the best way to critique a test weld unless it's a GMAW(SC) test of course. I've seen more then enough 6" qualified welders (stapped & bent) over the years that couldn't concistently pass a B31.3, Normal Fluid Service criteria radiograph to save their souls, let alone pass a 2" qualification test that is radiographed!

Regardless of what rick028 does or what we think he should/could do, let me pass on an old adage that was given to me as sage advise almost 40 years ago and has never failed me- "A welders qualification test is only a license to make his first production weld on your job, after that it's your job to see if he keeps it " Seldom
"There's no such thing as a welding problem, there are only welding puzzles of assorted sizes!"

 

[moseley]

Seldom,
You are totally right, most welders are good excuse givers! I see the same thing about the straps and bends quiet a bit also. But the tests are to see if he can perform under "perfect conditions". Then when he has to turn upside down then there is the actual test. I just don't see how he could take 1 test to get the quals he wants. Maybe I am misunderstanding or the question is not a question? Thanks for the age old advice!

 

[Seldom]

Hi moseley,
Nope, you're ok!
As so often happens with anybody that posts a question, we sometimes forget to include all the info that's needed for a specific reply or maybe we don't even want a specific answer. Post'ers know what they are asking but the Reply'er sometimes has to make assumptions interpreted from the written word. So nobody is right or wrong necessarily, we're just responding to what we think is wanted! ;-) Seldom
"There's no such thing as a welding problem, there are only welding puzzles of assorted sizes!"

 

[welding1]

I have an approval range calculator you may find useful, it covers both ASME 9 and EN287/288. I can E-mail to any body that would like a copy.

Regards
John

http://www.gowelding.com

post@gowelding.com

 

[pandithan]

1) for welder perfomance test for pipe.
A) pipe dia range
As per ASME section 1x , Qw-452.3, there is restriction on minimum dia qualification. maximum is unlimited, for your requirement you have to qualify your welder with 2inch outside dia which will qualify min 1 inch pipe dia to unlimit
2) Wall thickness
there is a rescriction on max deposited weld metal for welder qualification (ref, QW.452.1)
qualify with 1/4 inch wall thickness

3) you have to qualify welder with 2 inch pipe with 1/4 inch wall thickness. this will satisfy your requirement

 

[Merzi]

John

I wouls appreciate if you can mail me the approvasl range calculator at
merzi1@edti-1.com

 

[sadra]

john
I will be glad if you can send me the approval range calculator at r_salimi@boushehr.sadragroup.com
thanks and regards,
R.Salimi

 

[Rjeffery]

john
Please, could you can send me the approval range calculator to nh_yankee@hotmail.com ?