Creep Embrittlement of Structural Components in Catalytic Reformer Reactor.

Abstract

During the last ten years, more than 70 incidents of creep embrittlement damage of structural components in catalytic reformer reactors which had been in long-term operation have been reported. Creep embrittlement is the loss of creep ductility in the heat-affected zone of welds or base metal. Creep void density, as related to stress concentration, revealed a critical stress intensity for a catalytic reformer reactor that was actually operated for the last 19 years. There was a threshold Larson-Miller parameter in the range of 19.0×103 to 19.5×103, above which creep embrittlement occurred. Creep crack growth tests were also performed to evaluate crack propagation and remaining life of the components. For the safety of these components, it was necessary to evaluate the creep void density because of the shortage of long-term crack propagation data.