电厂旋风分离器受热面管泄漏原因分析  

Cause Analysis on Leakage of Heating Surface Tube at Cyclone Separator in Power Plant

作　　者：谭永生 TAN Yong-sheng(China Datang Corporation Science and Technology General Research Institute Co.Ltd.,Northwest Branch,Xi’an 710021,China)

机构地区：[1]中国大唐集团科学技术研究总院有限公司西北电力试验研究院,西安710021

出　　处：《失效分析与预防》2023年第5期346-350,共5页Failure Analysis and Prevention

摘　　要：电厂旋风分离器受热面管先后发生2次泄漏。为防止类似泄露事故的再次发生,本研究对泄漏管表面进行宏观检查,测试其室温力学性能,并通过硬度测量、金相检查、扫描电镜分析及能谱测试等方法,进一步研究旋风分离器受热面管的泄露原因。结果表明:尿素溶液滴落在下方的受热面管上,其在高温下分解的产物与旋风分离器受热面管金属之间发生反应,引起受热面管的有效壁厚减薄,最终因无法承受内部介质的压力而发生泄漏。结合旋风分离器受热面管的运行状况及泄漏原因,提出加强常态化检查、优化雾化空气压力、外设管面保护材料等改进措施。The heating surface tube of the cyclone separator in the power plant leaked twice successively.In order to prevent the recurrence of similar leakage accidents,the leakage reason was explored.The macroscopic inspection on leaking tube surface was conducted,and its mechanical properties at the room temperature were tested.The techniques,including the Brinell hardness testing,metallographic inspection,scanning electron microscope coupled with energy dispersive spectrometer analysis were also applied.The results show that when the urea solution dripped on the heating surface tube,the corrosion reaction occurred between the decomposed product at the high temperature and the metal of the heating surface tube of the cyclone separator,thinning the effective wall thickness of the heating surface tube.In this way,the leakage accidents occurred due to the unbearable pressure of the internal media.Finally,combined with the operation status of the heating surface tube and the cause of leakage,relevant suggestions such as strengthening the normal inspection,optimizing the atomizing air pressure,and installing peripheral tube surface protection materials are put forward.

关 键 词：失效分析 受热面 旋风分离器 尿素 泄漏 

分 类 号：TG174[金属学及工艺—金属表面处理]