锅炉屏式再热器异径管接头爆管原因分析

Different Diameters Pipe Explosion Reason Analysis on Boiler Platen Reheater

某热电厂300 MW机组锅炉屏式再热器管异径接头处发生爆管及凸起鼓包现象。通过化学成分检测、室温拉伸试验、宏观观察、显微组织观察等手段检测后,认为再热器爆管及鼓包的原因为异径接头壁厚相差较大及管内壁车削加工过程中工艺控制不严,形成应力集中区域,最终造成鼓包或产生裂纹、发生爆管。针对以上原因,提出对锅炉受热面异径接头的内坡车削部位,特别是退刀槽处进行全面检查的建议。

Reducing joint tube explosion and convex bulge phenomenon of a thermal power plant boiler 300 MW units platen reheater tube. Through the detection of chemical composition test, tensile test, macro observation, microstructure observation and other means, think that the reason of reheater and drum kit for reducers and the inner wall of the tube wall thickness difference in turning process process control is not strict, thus forming stress concentration region, resulting in swelling or crack, tube explosion. In view of the above reasons, the inner slope turning part of the boiler heating surface reducers especially recess for a comprehensive examination of the proposal.