乙烯装置一段裂解炉管鼓胀变形失效分析

Failure Analysis of Bulging Deformation of Cracking Tube of Ethylene Cracker

通过对某乙烯装置裂解炉管进行鼓胀变形检查、炉管氧化分析、渗碳检查分析、显微组织分析、炉管内壁缺陷分析、化学成分分析和力学性能分析,找出了炉管局部鼓胀变形的失效原因。调查表明:裂解炉管严重鼓胀变形的主因是由于该处实际使用温度比未变形的管局部温度偏高,又由此引出渗碳和氧化较严重;由于温度偏高和氧化减薄使其膨胀蠕变,加上渗碳不均匀。使其鼓胀不均匀。由此造成严重鼓胀变形。

Though failure analysis of the furnace tube of an ethylene cracker by expansion deformation inspection, oxidation analysis, carburizing inspection, microstructure analysis, defect analysis of inner wall of furnace tubes and analysis of chemical composition and mechanical properties, the causes of localized tube bulging deformation were found out. The results show that the failure is due to the higher working temperature than that of un - deformed tubes, which leads to very serious earburization and oxidation. The high temperature and oxidation thinning cause expansion deformation. Uneven earburization leads to uneven expansion creep. Severe expansion deformation is the final result.