The physico-chemical performance test and creep fracture test have been carried out for material quality status of a cutdown-section from 10CrMo910 old main steam manifold having accumulative operation hours of about 180000h in thermal power plant under Anqing Petrochemical Company

and the residual service-life of it being assessed by using the classical extrapolation method from isothermal curves based on the results of persistent strength test etc.. Results show that the said old main steam manifold can still contiously be in safe operation for 100000h under normal operation conditions.