API 1104 Procedure Qualification.

[alkeeprollin]

API-1104 Section 5.4.22 states;
When welding pipe of different base materials. The procedure for the higher strength base material group shall be used
for the qualification of welding procedures.

1. Can you please inform, if I am to weld X65 grade material (Group 'C') to X42 grade material (Group 'A') I have to qualify a
weld procedure on X65 to X65 material or can I qualify the weld procedure with X65 to X42 material.

I would have thought it better to qualify the weld procedure on X65 to X42 material as this would give mechanical results
which are a true representation of the actual materials to be welded.

 

[SectionIX]

You are correct. When welding X65 to X42, use an X65 qualified procedure.

Your thought to make an X65 to X42 qualification is sound, and could be performed to show yourself and PHMSA (if necessary) the material combination will produce a sound weld. However, this new WPS would be limited to X42 to X65.

 

[alkeeprollin]

Thanks for clarification to question 1.

I have one further question.
Would a welding procedure qualification test for X70 to X70 material be acceptable for welding X65 to X42 material.

 

[SectionIX]

No.

 

[wegm]

alkeeprollin,
You can not use procedure that qualified with X70 in order to weld X65 to X42 because it is not permitted by par. 5.4.2.2 c of API 1104 (for materials with a specified minimum yield strength greater than or equal to 65.000 psi, each grade shall receive a separate qualification test). According to that paragraph with a X70 procedure you qualifies only for X70 welding.
Please have a look at this link that addresses the same issue:

http://www.weldinguide.com/gdanastasiadis/viewtopic.php?f=24&t=435

regards
wegm