摘要
针对某余热锅炉Incolly 800镍基合金换热管发生局部垢物堵塞并诱发腐蚀失效的问题,通过材料成分检验、金相组织检验、能谱分析测试、X射线衍射测试及Fluent模拟计算等手段进行分析。结果表明,管程沉积的盐类垢物在换热管局部高温区熔化,侵蚀换热管保护膜,导致换热管内壁发生熔盐腐蚀产生腐蚀沟槽。Fluent软件模拟进一步表明,换热管口存在边缘效应,导致距离管口一定距离中心处发生湍流流动,边界层传热恶化使管内壁产生局部高温是发生腐蚀失效的主要原因,可通过增设防腐蚀套管预防此类问题的发生。
Block happened in waste heat boiler Incolly 800 nickel-based alloy heat exchange tubes and then corrosion failure followed. Through many measures taken such as material composition test, microstructure examination, energy spectrum analysis, X ray diffraction test and Fluent simulation, the results showed that dissolve of deposition of salt happened in the tube side in local high temperature situation, which melting the heat exchange tube protective film, finally local corrosion groove produced. Fluent simulation further showed that the heat exchange tube mouth had the edge effect, which leaded to turbulent flow in the nozzle center in a certain distance from the heat exchanger tube mouth, heat transfer deteriorated in boundary layer of the inner wall of the tube, producing local high temperature, the main reason of corrosion. This failure can be prevented by adding anti-corrosion sleeve.
出处
《石油化工设备》
CAS
2016年第2期73-76,共4页
Petro-Chemical Equipment
关键词
余热锅炉
熔盐腐蚀
腐蚀沟槽
边缘效应
waste heat boiler
fused salt corrosion
corrosive groove
edge effect
