某柴油发电机排气膨胀节开裂原因分析  

Analysis of Cracking Causes of Exhaust Expansion Joints in a Diesel Generator

作　　者：杨帆 朱兵 YANG Fan;ZHU Bing(Nanjing Boiler and Pressure Vessel Inspection Institute,Nanjing,Jiangsu 210019)

机构地区：[1]南京市锅炉压力容器检验研究院,江苏南京210019

出　　处：《化工装备技术》2025年第2期48-51,共4页Chemical Equipment Technology

摘　　要：某柴油发电机排气膨胀节服役时间未满1a即发生开裂泄漏。通过宏观观察、化学成分分析、金相组织分析、硬度检测和断口分析等方法确定膨胀节的失效原因为疲劳开裂。纵焊缝余高偏大,导致应力集中,形成疲劳源,降低了膨胀节疲劳寿命。在机组振动产生的交变应力作用下,膨胀节发生了疲劳开裂。The exhaust expansion joint of a diesel generator cracked and leaked before serving for less than one year.The failure cause of the expansion joint was determined to be fatigue cracking through macroscopic observation,chemical composition analysis,metallographic structure analysis,hardness testing,and fracture analysis.The excess height of the longitudinal weld seam is too large,which leads to stress concentration and forms a fatigue source,reducing the fatigue life of the expansion joint.Under the alternating stress generated by the vibration of the unit,the expansion joint undergoes fatigue cracking.

关 键 词：柴油发电机 排气膨胀节 焊缝余高 疲劳开裂 

分 类 号：TG174.4[金属学及工艺—金属表面处理]