S275 to S355 material welding

[Nidgeo]

Hi,

We qualified our welders in S275 to S355 materials in AWS D1.1, SMAW, 3G position and submitted to client and client has approved the WPQR . While during the production welding one of our qualified welder was welding S275 to S275 material and another welder was welding S355 to S355 material with the approved WPQR (S275 to S355), with same parameters, but client has stopped the work and insisted to qualify the welders separately in S275 to S275 material and S355 to S355 material for preforming the job instead of single WPQR (S275 to S355). My question is do they really required sperate qualification for S275 to S275 and S355 to S355 ? or S275 to S355 material qualification is enough to weld the above materials?

 

[gtaw]

First question: Are the WPSs qualified in accordance with AWS D1.1. The base metals you listed are not listed in D1.1, so they have to be qualified by testing. It would appear that you need 3 PQRs: one for S275 to S275, one for S355 to S355, and finally a PQR for S275 to S355. If all the variable are the same, i.e., same process, same filler metal, etc., the three PQRs can be used to support one WPS.

If the welders were qualified to the WPS that includes the three combinations supported by the PQRs listed above, you're good to go.

Generally, the welder performance test is where the welder demonstrates the ability to deposit a sound weld and can follow the WPS as written. AWS D1.1 only covers carbon and high strength low alloy steels. Unlike ASME, AWS D1.1 doesn't include provisions for dissimilar metals, so it can get pretty muddy really quick. The Owner (your customer) has final authority to accept the contractor's WPS and supporting documentation. It's the Golden Rule of business; He who holds the gold makes the rules. If the Owner says he wants the welders qualified on the combinations, that's what they get.

Best regards - Al

 

[Nidgeo]

Thanks