Q. Show the Welding Processes and Restrictions?
Welding may be performed manually, semi-automatically and or automatically using any process or combination of processes accepted by ASME Section IX and this specification, provided the same welding process or the combination of welding processes has or have been used in the Procedure Qualification Record, PQR. If not, fresh PQR with the applicable welding process have to be resubmitted for approval.
No welding processes other than the following are authorized for use:
a. SMAW - Shielded Metal Arc Welding
b. GTAW - Gas Tungsten Arc Welding
c. SAW - Submerged Arc Welding
d. GMAW - Gas Metal Arc Welding (short arc process only) and only for root pass
Where access or wall thickness precludes the use of double welded butt joints, single welded joints shall be made using a root pass deposited by the GTAW or GMAW (short arc process only).
Gas tungsten arc welding shall require the addition of filler metal.
Internal purging with inert gas is required for gas tungsten arc welding of single-welded butt joints in non-ferrous metals, and ferrous metal with over 3% total alloy content.
Repair welding shall be with low hydrogen process. At least one repair procedure shall be qualified for all position welding.