再沸器管板开裂原因  

Reasons for cracking of reboiler tube plate

作　　者：陈静[1] 孔范洋 许铁群[1] 陈怀宁[1] CHEN Jing;KONG Fanyang;XU Tiequn;CHEN Huaining(Institute of Metal Research,CAS,Shenyang 110016,China;North Huajin Chemical Industries Co.,Ltd.,Panjin 124099,China)

机构地区：[1]中国科学院金属研究所,沈阳110016 [2]北方华锦化学工业股份有限公司,盘锦124099

出　　处：《理化检验(物理分册)》2025年第4期59-63,共5页Physical Testing and Chemical Analysis(Part A:Physical Testing)

摘　　要：某乙烯裂解装置中再沸器管板发生开裂。采用宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜及能谱分析等方法对管板的开裂原因进行分析。结果表明:焊接工艺控制不当使管板材料产生马氏体淬硬组织,在应力和淬硬组织的共同作用下,管板与管束间隙处的焊缝区和热影响区产生焊接冷裂纹;工艺水或急冷油进入裂纹,在S、O等腐蚀性元素的作用下,裂纹处的材料发生应力腐蚀开裂,裂纹进一步扩展,最终导致孔桥或管束发生开裂。Cracking occurred in the reboiler tube plate of a certain ethylene cracking unit.The cracking reasons of the tube plate were analyzed using macroscopic observation,chemical composition analysis,hardness testing,metallographic examination,scanning electron microscopy and energy spectrum analysis.The results show that improper welding process control led to the formation of martensitic quenched microstructure in the tube sheet material.Under the combined action of stress and quenched microstructure,welding cold cracks occurred in the weld zone and heat affected zone at the gap between the tube sheet and the bundle.The entry of process water or rapid cooling oil into the crack,under the action of corrosive elements such as S and O,the material at the crack underwent stress corrosion cracking,further expanded the crack,and ultimately led to cracking of the hole bridge or tube bundle.

关 键 词：再沸器 冷裂纹 应力腐蚀开裂 焊接工艺 淬硬组织 

分 类 号：TB31[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]