裂解炉稀释蒸汽管道膨胀节故障原因分析及消缺措施

FAULT ANALYSIS AND DEFECT ELIMINATION MEASURES FOR EXPANSION JOINTS OF DILUTION STEAM PIPELINES IN CRACKING FURNACE

独山子石化公司乙烯老区6号裂解炉在运行中通过横跨温度、炉管温度等工艺参数的差异,排查发现4组稀释蒸汽管道上的膨胀节波纹管过度拉伸,严重超出设计范围;同时,导流筒严重变形堵塞管道,不仅影响管道通量,若不能及时发现,膨胀节处可能发生断裂、物料泄漏的生产事故,严重影响装置的平稳运行。为彻底解决膨胀节对裂解炉运行的影响,通过对工艺管道应力的重新核算及增加部分弹簧吊架、支撑,将膨胀节更换为直管段,消除了裂解炉因膨胀节变形导致的运行隐患。

Based on the investigation of the differences in process parameters such as crossover temperature and furnace tube temperature during the operation of the No.6 cracking furnace in the old area of PetroChina Dushanzi Petrochemical Company,it was found that the bellows of four expansion joints of diluent steam pipelines were overstretched and seriously exceeded the design scope.At the same time,the draft tube was seriously deformed and blocked the pipeline,which not only affected the flux of the pipelines,but also led to the fracture and material leakage at the expansion joints if it cannot be found in time,seriously affecting the smooth operation of the plant.In order to completely solve the influence of expansion joint on the operation of cracking furnace,the expansion joint was replaced by straight pipe section by re-calculating the stress of process pipelines and adding part of spring hanger and support,thus eliminating the hidden trouble caused by the deformation of expansion joint of cracking furnace.