Thanks metengr,
I was not clear.
PWHT is required per service. The question is addressed to the integrity of the equipment during PWHT.
Is it normal to install an internal reinforcement (ring welded to the shell) to avoid deformation of the shell due to PWHT. The PWHT can really affect the shell...
IS A REINFORCED,INTERNAL RING WELDED TO THE SHELL, REQUIRED FOR A PWHT OF A C.S VERTICAL PRESSURE VESSEL 3/4" SHELL thk, 12'-0" I.D X 16'-0" T/T, two 7/8" ell. heads?
There is a concern about deformation of the shell.