摘要
通过宏观检验、金相检验等方法,对某焦炭塔进料管线弯头在运行过程中发生泄漏的原因进行了分析。结果表明:在焦炭塔生焦期间,管线内部介质周期交替循环,几种介质温度差别较大,存在急冷、急热工况。使管线内部承受较大的交变热应力,诱发管内壁产生热疲劳裂纹。管线长期运行金相组织发生退化,晶界大量呈串条状碳化物析出,使晶界弱化,裂纹沿晶界扩展。
The leakage reasons of the coke drums pipes during operation were analyzed by methods of macroscopic examination metallographic examination,scanning electron microscope and energy spectrum analysis and so on.The results show that during the period of coke forming,the inside fluid were different in the pipes,and Periodic exchange each other.The temperatures of the different fluid were varied greatly.Due to the large temperature fluctuation,the inside of the pipes would with stand a large alternating thermal stress,which resulted in transversal fatigue crack appearing in the tube.At the same time,the microstructure has degradation due to the long time operation.There was more carbide precipitated at the grain boundaries,which waken grain boundary.The cracks form at grain boundaries and expand along grain boundaries.
作者
顾宝兰
于海洋
徐彤
刘文
Gu Baolan;Yu Haiyang;Xu Tong;Liu Wen(China Special Equipment Inspection and Research Institute,Beijing,100029;State Administration for Market Regulation Key Laboratory of Special Equipment afety and Energy-saving,Beijing,100029)
出处
《中国特种设备安全》
2019年第10期74-76,共3页
China Special Equipment Safety
基金
国家重点研发计划(批准号:2016YFC0801901)
关键词
焦炭塔管线
交变热应力
热疲劳裂纹
Coke drums pipes
Alternation thermal stress
Thermal fatigue crack
