If K= 0.6 and a2/ts= 0.29, then a2 can be calculated for various thicknesses. If the corner joint plates are machined such that it is always 45° on the "Z" plate at a2 and 15° minimum (28-2 (f)(3)) on the thinner plate, Does this satisfy 28-2 (f)(4)?
If the WPS / PQR is in accordance with ASME Section VIII division I which uses Section IX for welding, then the answer is that only the one process used in the PQR is qualified.
Without knowing how the procedure has to be qualified, I cannot give an accurate answer.
Gas for GTAW
I am looking for the best gas to use that will give me the lowest hardness in a non-PWHT'd weld and HAZ.
I would like feed back on using 75% Argon and 25% Helium.