热电厂304不锈钢板式冷油器的失效分析

Failure Analysis of 304 Stainless Steel Plate Oil Cooler in Thermal Power Plant

不锈钢板式冷油器因为冷却效率高占用空间少,是热电厂使用较多的冷却设备,然而由于冷油器工作条件复杂,极易导致冷油器失效泄漏。以某热电厂失效板式冷油器为研究对象,通过宏观观察、化学成分分析、金相组织分析、微观形貌分析、腐蚀产物元素分析,结合服役工况及环境,综合分析了该板式冷油器的失效原因及机理。结果表明:板式冷油器失效泄漏主要是发生了氧腐蚀,同时伴有氯离子点腐蚀及应力作用而造成穿孔泄漏。为防止板式冷油器再发生此类失效事件,建议更换为材质耐蚀性更好的板式冷油器。

The stainless steel plate oil cooler is widely used in thermal power plants because of its high cooling efficiency and less occupied space.However,the oil cooler is easy to leak because of its complicated working conditions.Taking the failure plate oil cooler of a thermal power plant as the research object,the failure reason and mechanism of the plate oil cooler were analyzed through macroscopic observation,chemical composition analysis,metallographic structure analysis,micro morphology analysis and corrosion production element analysis with consideration given to service condition and environment.Results showed that the failure leakage of the plate type oil cooler was mainly caused by oxygen corrosion,accompanied by chloride ion spot corrosion and stress effect,resulting in perforated leakage.In order to prevent the failure of the plate type oil cooler,it was suggested that the plate type oil cooler material with better corrosion resistance could be used.