缠绕管式换热器换热管泄漏失效分析  

Failure Analysis of Tube Leakage in Heat Exchange Tube of Coiled Tubular Heat Exchanger

作　　者：雷万庆 张凯 张建晓 温宝峰 Lei Wanqing;Zhang Kai;Zhang Jianxiao;Wen Baofeng(Lanzhou LS Testing Technology Co.,Ltd.,Lanzhou 730314,China;Lanzhou LS Heavy Equipment Co.,Ltd.,Lanzhou 730314,China;Pressure Vessel Special Material Welding Key Laboratory Cultivation Base of Gansu Province,Lanzhou 730314,China)

机构地区：[1]兰州兰石检测技术有限公司,兰州730314 [2]甘肃省压力容器特种材料焊接重点实验室培育基地,兰州730314 [3]兰州兰石重型装备股份有限公司,兰州730314

出　　处：《压力容器》2019年第1期65-71,53,共8页Pressure Vessel Technology

摘　　要：某石油化工厂对换热器管程进行打压试验时发现严重泄漏。采用化学成分分析、力学性能试验、金相检验、扫描电镜分析等方法,对换热器泄漏失效原因进行了分析。结果表明,管程、壳程介质中均含有S2-,Cl-,造成换热器下端管程内外壁的点腐蚀;同时,缠绕管在应力和腐蚀介质的共同作用下,从内壁向外发生应力腐蚀开裂,最终导致换热器腐蚀泄漏而失效。A petrochemical plant found serious leakage in the tube pass of a heat exchanger when conducting pressure test on the heat exchanger.The leakage failure cause of the heat exchanger was analyzed by the methods of chemical composition analysis,mechanical property test,metallographic inspection,SEM analysis,etc.The results show that there are S^2-and Cl^-ions in the media in both the tube pass and shell,which cause pitting corrosion on the inner and outer walls of the tube pass at lower end of the heat exchanger;At the same time,under the joint action of tensile stress and corrosive medium,the stress corrosion cracking occurs from the inner wall outward,eventually leading to failure of the heat exchanger due to corrosion leakage.

关 键 词：换热管 泄漏 失效分析 

分 类 号：TH49[机械工程—机械制造及自动化] TQ050.7[化学工程]