Been gone for a couple of weeks taking care of a multitude of work, family, church, and AWS AZ Section business.
I'd like to ask another question here gentlemen:
Has anyone referenced Technical Inquiry for "Other Than Steel Backing" made per D1.1:2008? The response is that other backings may be used on prequalified joints where the backing is to be removed and a fillet weld used to replace it after clean up by grinder or other methods. Referenced 2.17 & 5.10 in their response.
Subject: Other than Steel Backing and Prequalified Joints
Code Edition: D1.1:2008
Code Provision: Subclauses 2.17 and 5.10
AWS Log: D1.1-08-I02
Inquiry: Can the use of backing “other than” steel be considered prequalified where back-gouging and
welding is performed on the second side?
Response: Yes, provided all conditions for a prequalified weld are met. Backing other than steel
is not a prequalified substitute where steel backing is required.
So, I suspect you may use ceramic or copper (or others) where it will be removed and welded from the second side, but not if it is to be left in place or is not able to be properly cleaned and welded from the second side because of space or other limitations.
Thus, the OP may be able to use copper or ceramic to back up his weld without going through the PQR process if conditions are acceptable.
???? Just my two tin pennies worth.
Have a Great Day, Brent