NORMALLY IN API 1104 A CHANGE IN FILLER METAL TO ANOTHER IS ESSENTIAL VARRIABLE THAT NEED REQUALIFATION
5.4.2.6 Filler Metal
The following changes in filler metal constitute essential variables:
a) a change from one filler metal group to another (see Table 1);
b) for materials with a SMYS greater than or equal to that of the material specified as API 5L Grade X65, a change in
the AWS classification of the filler metal (see 5.4.2.2).
Changes in filler metal within filler metal groups may be made within the material groups specified in 5.4.2.2. The
compatibility of the base material and the filler metal should be considered from the standpoint of mechanical
properties