Who is certifying the test reports as being accurate and true? In my opinion if you do not witness the test, you should not be the individual signing the certification. You can sign for the tests and the test results you performed, but you can not sign the certifying statement if you can not say with certainty who welded the test coupon, the position of the test, what electrode was used, etc.
Only a newbie inspector can honestly say they have not seen instances where welder X took the test for welder Y or they have never seen a doctored welder performance test report.
I actually had a situation were I failed two welders and yet they managed to weld for nearly two years using my paperwork. Why? Simple, the inspector, a CWI, who knew me never bothered to read the entire test record that indicated the welders failed the bend test. The inspector saw my letterhead and assumed they had passed the performance tests. Now, older and wiser, I never print out a test report unless the welder passes the tests.
Never sign a piece of paper unless you know the information is correct and valid. Your name and reputation depends on your signature. If your signature can not be trusted, neither can you. The bottom line it that you have to protect your good name and reputation. More than one inspector has had to find a different line of work because their reputation was sullied because of a simple indiscression. If I had to guess, I would say the number one mistake an inspector can make is signing for work they did not witness because they "trusted" someone else.
Best regards - Al
Al makes good points.
I would be more comfortable with the signatures the other way around..
A testing lab signs off on only the tests they do (send out for RT for example) and are very clear about the fact.
If I were doing the guided bends or the RT for stations across the fruited plain. even for the same company, I would be most comfortable having a specific line in the test report that records the work I did. Send that back to the home shop and have the supervisor in authority (You said a knowledgable supervisor who gave the test) have that supervisor put the certification signature in the apropriate block. There is bigtime wisdom in signing only for items you have specificly wittnessed.
So... The moral of the story? I don't see the process you describe as necessarily out of compliance, but I don't particularly like it either... Would be more comfortable with peoples signatures specifically attached to things they wittness.
If it's that important to have a CWI stamp on the cert (even though it's not a code requirement) than maybe consider making your *Knowledgable Supervisors* CWI's.