Welder Qualification issues. 1

[cntrleng]

Can someone tell me the difference between qualifiying a welder under aws d1.1 and the asme standards? Will an asme certification cover welders to work to designs that call out d1.1 as the welding spec or should the welder have both?
Why do pre fab pipe practice coupons only come with 37 1/2 degree bevel when aws d1.1 calls for a 60 degree included angle?
Thanks

 

[CWIC]

cntrleng:
The D1.1 does not recognize the ASME requirements for welder performance qualification. Subsection 1.2(3) denotes "pressure vessels or pressure piping" applications are not intended to be used for with this code.

However, subsection 4.1.2.1 "Previous Performance Qualifications" may be accepted for use with approval by the Engineer. This has happened on a few projects in the past, but that has been about 10 years back. Because of the concern for the workmanship and technique requirements of the Structural Welding Code, I have not seen ASME qualifications accepted in a long time (10 years). While the welder(s) may have the skill to perform structural welds, they are not usually aware of the structural code requirements.

Much is dependant on the process(es), material, position, thicknesses invloved and joint geometry. These variables are distinctly different for the two codes. One example is the GTAW is code approved, but not prequalified in the structural code.

BTW, smaller groove angles (<60 degrees) are permitted by the structural code, but procedure qualification is required.