Surveillance Program for Evaluation of Material Degradation after Long Term Service in the Petroleum Refining Reactor Pressure Vessel (1 1/4Cr-1/2Mo)

Abstract

A suitable surveillance test program was developed for evaluating the change in fracture toughness of material after long service operation using a retired petroleum reactor pressure vessel. The surveillance program is based on the correlation derived in advance from the standard Charpy absorbed energy (C_V) and fracture toughness (K_Ic, K_Id) data for pre-service material and on the Charpy energy (C_V) obtained from the periodic surveillance after service operation.
It is here demonstrated that K_Id(C_V) estimated from the Charpy data shows a good agreement with valid K_Id determined experimentally for all the base metal, weld deposit and heat affectted zone (HAZ) of the material. The validity of the surveillance program was also discussed.