Al, thanks for your reply. Now that I've had some time to sit down and study the code, I agree with what you are saying. the other day I realized that our PQR/WPS was done w/ a backing bar, and the parts we are getting ready to fab would not have a backing bar, and I had to make a quick decision on the fly.
FOI (for our information) Table 3.1 Essential variables of WPS, will not allow one to change from a permanent backing to a temporary backing or no backing. Also you can't omit the backgouge, but it can be included.
Also Table 3.9 Essential varaibles for the welder, the welder is not certified if the omission of backing is done when he tested w/ a backing bar.
Both these issues apply to my situation, so I'l have to qualify a PQR/WPS, thanks Chris
Well here it is 2 1/2 years later and I have to re-qualify some more welders with aluminum, and I've purged all the information I learned from back then, see what happens whe you don't do something all the time, anyway.
Aluminum D 1.2 Table 3.9 "Welding Personnel Peroformance Essential Variables Changes Requiring Requalification"
"Welders- The omission of backing (if used in the WPQR test)" has an X in in which means it applys in my case.
Why would I have to re-certify a welder if he passed the test with a backing bar, but now if he has to backgouge and weld the second side, re test? That doesn't make sence to me.
I could understand if he tested and passed doing a backgouge on his plate test, that he hasn't proved he could fuse to a backing bar, but because he backgouges we know he'll most likely get full penetration through the joint.
Chris
When a welder is qualified with backing, he is qualified to weld CJP with backing or when the first side joint is back gouged and welded from the second side to complete the CJP.
Partial joint penetration groove welds and those that are back gouged are considered to be welded with backing. Refer to D1.1-1997 (that's the one I had on my desk at the time I looked this up) clause 2.5.1. More than likely the latest edition will have the same clause.
You do not have to requalify the welders that were qualified with backing if you are now goint to employ BG before welding the second side.
Best regards - Al