Clarification regarding Non confurmity

[Uma sankar Sankar]

Dear Experts

ASTM A 692 pipe joint welded on June 10th 2023 ,NDT RT result was failed , while attending  repair,come to know that drawing revised on June 20th ,As per revised drawing required pwht.As per old drawing pwht not required.

What may be the root cause?

What will be the proposed correction?

If the pqr done with pwht ,is it possible to prepare wps with and without pwht?

But pwht is Essential variable for welding procedure specifications?

During investigation 15 joints were found in the same situation, what will be the action can we take?

I believe,I will get the best answer