[MW:8469] Minimum Weld lengh for welder qualification

Dear friends:
 
Sometimes we have qualified four welders in the same coupon, for example in a 36" Ø pipe coupon the first two  welders apply in overhead position one from 3 to 6 and the other one from 9 to 6, after they finish the cuopon is rotated in order to start the other welder couple as the same process. This has been accepted by our clients but I'd like to know if some code has a minimum lenght to be welded for qualification or it must be the entire cinrcunference of the pipe cuopon to be welded by a welder. I want to be prepared if a client supervisor ask me about it.

Eduardo Calva

QC Coordinator
Global Industries
México.