Suitable Impact Test for LTCS?

Whether the below impact test conducted is acceptable for LTCS as following,

Test piece mady by GTAW+SMAW.(Ex. pipe 10" OD,15.09THK)

Weld metal thick for each process for the above respectively is 7mm+rest thick.

Impact test conducted for the thickness having each process separately.(GTAW having thick 7mm separately and SMAW having remaining thick separately)

If above is acceptable,what basis actual material thickness to be considered for tempearature reduction.Is weld metal deposited by each process or total base metal thick is required as per ASME B31.3 sec323.3.4.