In this article we will discuss the thickness qualification range of base metal and weld metal for Procedure qualification and Welder performance qualification as per ASME code.
Thickness Qualification Limit for Procedure Qualification (PQR)
1) As per ASME Section IX
a) For Groove Weld (As per table QW-451.1)
Note- For PQR there is no any limatation on minimum thickness of weld metal
b) As per QW-403.6 (Thickness Range qualified when Impact test is required)
c) As per QW-403.9 (Thickness Range qualified when any weld pass thickness is greater than 13 mm)
d) As per QW-403.10 (T-Limit for Short circuit mode)
This thickness limitation for base metal and weld metal is only applicable in case of GMAW and FCAW when short circuit mode was used during test coupon welding.
e) For Dissimilar Base Metal Thickness (as per QW-202.4)
f) For Fillet Weld (As per table QW-451.3 and QW-451.4)
g) For Hard-facing and Weld Overlay (As per table QW-453)
2) As per ASME B31.3
For Groove weld when Impact Test is required (as per table 323.3.1)
When construction code will be ASME B31.3 and impact test is required than Base metal thickness range will be as mentioned below and in that case ASME B31.3 will take precedence over ASME Section IX (Refer ASME Section IX, QG-100(b); ASME code interpretation Record No.-15-586)
Thickness Qualification Limit for Welder Qualification (WPQ)
a) For Groove Weld as per ASME Section IX, Table QW-452.1(b)
– Base Metal qualification limit is not applicable for welder qualification
– There is no restriction on minimum weld deposit thickness limit as per table QW-452.1(b)
– Weld metal thickness limit is only applicable for welder (performing manual and semi-automatic welding) and not applicable for Welding operator (performing automatic or machine welding).
b) Weld Metal thickness limit for GMAW and FCAW process when Short-circuit mode will used during qualification (as per table QW-355 QW-404.32 & of ASME Section IX)
c) For Hard-Facing and Weld Overlay as per table QW-453
Note: In case of Hard-facing and Weld Overlay there are no any thickness restriction is applicable weld deposit thickness and thickness restriction is only applicable for Base metal thickness.