Question (1): A pressure vessel is constructed of P-No. 1 and P-No. 8 materials, and is intended for lethal service. The vessel is PWHT. After PWHT, but before performing the hydrotest, the interior of the vessel has a stainless steel lining applied using plug welds. Does Note (2)(c)(5) of Table UCS-56 in Section VIII, Division 1 permit the liner to be applied after the vessel has been PWHT without the need to perform any additional heat treatment?
Reply (1): Yes, provided that the preheat requirements are met.
Question (2): Does UCL-51 permit the liner to be repaired by welding to the P-No. 1 base material after the vessel has been PWHT without the need to perform any additional heat treatment?
Reply (2): Yes, with the acceptance of the Authorized Inspector.