裂解炉蒸汽减温器内套和管线开裂失效分析

Failure Analysis of Inner Sleeve and Steam Pipeline Cracking of Cracking Furnace Temperature Regulator

乙烯装置运行中发生了多台裂解炉减温器后不锈钢蒸汽管线发生泄漏导致的装置停车事故。结合生产工艺对减温器内套和蒸汽管线的失效机理和原因进行了分析,确定减温器喷水雾化效果不良导致了蒸汽管线局部温度波动较大、内壁局部产生交变热应力和介质反复蒸发浓缩是最终导致管线热疲劳开裂和Cl-应力腐蚀的主要原因。

Abstract.. Leakage in working was found with the stainless steel steam transportation pipelines in the downstream of cracking furnace temperature regulators in the ethylene production unit. The failure mechanism of temperature regulator lining and steam pipelines were analyzed. As the results, factors that larger local temperature fluctuation of steam pipelines because of poor atomi-zation effect of temperature regulator, local alternating thermal stress occurring occurred in inner wall and process medium has been vaporized and concentrated again and again were identified as the main causes for the final pipeline thermal fatigue cracking and chloride ion stress corrosion.