近年来，国内多家石化企业的延迟焦化装置转油线钢制密封圈在投用较短的时间内相继发生断裂失效。对密封圈进行失效分析，结果表明：奥氏体不锈钢密封圈出现失效的主要原因是发生连多硫酸应力腐蚀开裂。建议选用马氏体型不锈钢0Cr13作为密封圈的材料，可有效避免其发生连多硫酸应力腐蚀开裂。

In recent years, the steel sealing ring of delayed coker transfer lines in many domestic petrochemical enterprises failed after usage for a short period of time. The failure analysis results of the sealing ring showed that the main cause of failure of the austenitic stainless steel sealing ring was the occurrence of polythionic acid stress corrosion cracking (PASCC). It was recommended to use martensitic stainless steel 0Cr13 as the material of the sealing ring, which could effectively avoid the occurrence of PASCC in the sealing ring.