FluidicTech
Mechanical
We often butter P1, P4, P5A and P5B base materials when welding them to P8 material to avoid PWHT (of the final joint) of the P8 material. When the design temperature is significantly high, we use Inconel to butter, then heat treat, and then use Inconel filler for the final joint. We currently have processes qualified for buttering with SMAW, heat treating, and completing the joint with GTAW & SMAW. We are looking at qualifying some new procedures that use FCAW or SAW to complete the joint after the buttered material has been heat treated.
Paragraph QW-283 of Section IX deals with buttering. All buttering thicknesses are or will be 3/16" or greater. The QA department believes that we can, under QW-283.4(b), use Inconel plate for the test coupon which matches our Inconel filler, and subsequently qualify all P1-P8, P4-P8, P5A-P8, and P5B-P8 welds at the same time without having to qualify procedures for each of these different base metals.
I interpret paragraph QW-283.4 as stating that if "an essential variable is changed in the portion of the weld to be made after buttering" a new qualification can be made by using inconel plate that matches the filler metal. However, because changing the base metal is an essential variable in the portion of the weld prior to buttering, this is not applicable. Therefore, we would have to qualify a different procedure for each different base metal.
I am not a Section IX expert, and the QA department has more experience here than I do. But, their interpretation doesn't seem quite right to me. Who is right? Please elaborate on the intent of paragraph QW-283.4. Sorry for the length...
Paragraph QW-283 of Section IX deals with buttering. All buttering thicknesses are or will be 3/16" or greater. The QA department believes that we can, under QW-283.4(b), use Inconel plate for the test coupon which matches our Inconel filler, and subsequently qualify all P1-P8, P4-P8, P5A-P8, and P5B-P8 welds at the same time without having to qualify procedures for each of these different base metals.
I interpret paragraph QW-283.4 as stating that if "an essential variable is changed in the portion of the weld to be made after buttering" a new qualification can be made by using inconel plate that matches the filler metal. However, because changing the base metal is an essential variable in the portion of the weld prior to buttering, this is not applicable. Therefore, we would have to qualify a different procedure for each different base metal.
I am not a Section IX expert, and the QA department has more experience here than I do. But, their interpretation doesn't seem quite right to me. Who is right? Please elaborate on the intent of paragraph QW-283.4. Sorry for the length...