Hi,

Our welders have welded IIB and IIIB separately. We do not have a IIB to IIIB weld made on a PQR. AWS D17.1 states that material group is an essential variable. Am I interpreting this correctly? The welder is certified to weld IIB to IIIB, but I need a IIB to IIIB PQR to qualify the procedure?