重油催化裂化装置外取热器底部松动风管道法兰断裂失效分析

FAILURE ANALYSIS ON THE FLANGE FRACTURE OF THE LOOSENING WIND PIPE IN THE EXTERNAL HEAT COLLECTOR OF THE RFCC

重油催化裂化装置中有许多部位因温度高而应用不锈钢材质,主要为304或321不锈钢。在装置正常运行中,外取热一松动风管道在法兰处发生开裂,催化剂从取热器内部倒流出来。同时发现其他松动风管道同一位置的法兰与接管连接处,也有裂纹存在。松动风管断裂造成携带催化剂的烟气大量漏出,对装置安全生产造成了威胁。文章对外取热器底部不锈钢松动风管道断裂原因进行了分析,闸明了材料验收在石化装置中的重要意义,提出了预防措施。

Stainless steel,mainly Grade 304 or 321 are often used on many parts of the RFCC due to high temperature.In the normal operation of the device,the loosening wind pipe of the external heat collector cracks in the flange and the catalyst flows out from the heat collector.Cracks also exist at the joint of the flange and the connector in other loosening wind pipes.The fracture of the loosening wind pipe resulted in large leakage of flue gas containing catalyst,posing threats to the safe production of the unit.This paper analyzes the fracture reasons for the stainless steel loosening wind pipe at the bottom of the external heat collector.It clarifies the importance of acceptance of materials in petrochemical units and proposes preventive measures.