D17.1 2001
"4.4.1 Written Welding Procedure
All welds produced to the requirements of this specification shall be accomplished in accordance with a written welding procedure. Guidelines for written welding procedure contents for typical welidng process covered by the doccument are suggested in AWS B2.1. The final decision on specific format and content shall be at the discreiton of the Engineering Authority.

"4.4.3 Method of procedure qualificaiton.
Welding procedure qualificaiton may be accomplished in accordance with the requirements of AWS B2.1 as deemed applicable by the Engineering authority."


The above seems to allow wiggle room for bold Engineers.

5.2.3.2 Recommended Shielding Gasses
"Table 5.2 shows sheilding gas or gas mixtures recommended... ...When parts are welded using a qualified Welding Procedure Specificaiton (WPS) the chemical composition, volume percentage, and flow rate of each gas shall be as specified in the WPS."

I believe this inferrs that production welds SHALL (shall means will) be as specified on the WPS.... Maybe it would be more clear if it stated that the Shield gas in the WPS SHALL be the same as in the PQR. Maybe that is assumed? But it doesn't say exactly that.


I think a new PQR is the best way to go... Especially if the gas suggested is not the gas recommended in table 5.2