Governing thickness for heat treatment
Posted: 15 Dec 2010, 16:26
What is the governing thickness for heat treatment when we weld a weldolet on piping?
You must see 331.1.3 to determine the governing thickness which may or may not qualify for heat treatment.
For the case of weldolet, sketch 1 of Fig. 328.5.4D would be applicable where Tb is the thickness of the weld joint and tc is the throat size of the covering fillet.
You would have to perform heat treatment when Tb+tc > 2tm where tm is the minimum thickness requiring PWHT as per table 331.1.1 against the applicable P.No.