Stud Welding
Stud Welding
(OP)
When qualifying a stud welding procedure per AWS D1.1, using a particular manufacturer's equipment and set-up, may the subsequent stud welding WPS utilize any manufacturer's equipment with the same parameters? It is noted in ASME IX that a change in power source or stud gun model number represents a change in an essential variable. The AWS code is not so clear on that note.
RE: Stud Welding
I am assuming that your application was not prequalified as per 7.6.1?
RE: Stud Welding
Best regards - Al
RE: Stud Welding
So based on what is listed in ASW D1.1 Par. 7.6.1 and again for the manufacturer's qual test in 7.9.10, the arc shield, the combination of ferrule and flux, is an essential variable, and more important than power source and stud gun. Sounds like ASME Section IX is a bit out to lunch on this one.
RE: Stud Welding
I don't necessarily agree with that, but I do agree with what gtaw has stated; Different codes.
RE: Stud Welding
Let me ask you a follow-on question, if I may. AWS provides instruction to qualify a given stud weld setup including current, time and arc shield, and to document that setup in the PQR. Except for arc-shield, it appears that there are no limits to current and time (or other critical parameters) that can be used in the subsequent field WPS provided that the daily pre-production test demonstrates a sat result. If that is the case, why bother with a qual test and required 90 degree bend and tensiles, if a 30 degree pre-production bend test is equally discriminating. Can you tell that I'm a bit lost in the technical logic of the AWS Code on stud welding?
RE: Stud Welding
I can only say that the manufacturer has to qualify the stud welding operation. The upper and lower extents of the permissible current range are established by testing by the manufacturer. That information is provided to the contractor (end user) that is installing the studs.
The contractor installing the studs performs preproduction testing to verify the equipment and setting are capable of producing an acceptable weld.
One must also consider the fact that AWS D1.1 limits prequalification of WPSs to those materials listed by table 3.1. All other materials have to be qualified by testing. ASME Section IX deals with a wide variety of base metals, both ferrous and nonferrous, and does not have prequalified WPSs.
Best regards - Al
RE: Stud Welding
RE: Stud Welding
RE: Stud Welding