By MBSims
Date 05-30-2011 22:59
Edited 05-30-2011 23:02
Neither D1.1 nor ASME IX require hardness testing, except for hardfacing overlay or temper bead welding under IX. Where did your acceptance range come from? I suspect it could be a customer requirement, which is up to the customer to accept or reject.
The PQR is still valid for welds not subject to hardness testing qualifications.
By jarcher
Date 05-31-2011 05:47
Edited 05-31-2011 05:50
Mr. Sims is 100% correct, but I'm guessing you're asking the wrong question. There are a number of things that some customers want beyond a valid AWS or ASME WPS/PQR. Hardness is directly related to corrosion and fatigue resistance. For instance API specifies that low alloy steel for certain subsea parts cannot be below 197 BHN while if those parts are to come in contact with production fluid, the hardest they can be is 248 HV (NACE 0175/ISO 15156). Another example is that BP doesn't allow anything harder than BHN 325 on structural steel (Gulf of Mexico). The point being that welds are frequently asked to meet criteria other than just getting the required bends (ductility) and tensile strength, and the customer is paying the welds, right, so he calls the tune.