Pipe Qualification

Date 10-21-2002 23:54

Hi, I could use a bit of guidance. I currently need to qualify some welders to weld pipe of various wall thickness and diameter. The range is from 2 1/2" sch. 160 up to 8" sch. 160. So as you can see there is quite a bit of variation. My question: under ASME Section IX, if they were to qualify on the 2 1/2" pipe would that qualify for the 8" dia.? And if so would that also qualify them for the variation in wall thickness with the wall on 2 1/2" being approx. .552" and the wall on the 8" being approx. 1" thick? I would like to qualify for these ranges with one test.

Thanks,
C. Miller

By pipewelder_1999 (****)

Date 10-22-2002 03:01

Take a look at QW 452 "Performance Qualification Limits and Test Specimens" and QW461.1 "Performance Qualification-Position and Diameter Limitations" and your answers are there. Part of this is refered to in QW 303.

The answer cannot be given since you don't specify a process however the paragraphs refernced above shoud answer your questions. If this were SMAW groove welds, the answer is yes provided all other variables remain within range. In all cases I'm aware of increasing diameter is always OK and wall thickness is usuallt 2 time t he thickness tested for most processes.

Have a good day and I hope this helps.
Gerald Austin

http://www.weldinginspectionsvcs.com

By boilermaker (**)

Date 10-22-2002 13:32

If you were to aquire the 2 3/4" double xtra heavy wall tube coupons, this qualifies for unlimited thickness, and diameter, down to 1"...That's the test most of the contractors I work for administer for the ease of having to purchase a ton of 6" coupons....