摘要
针对潮州电厂2号机组600MW锅炉过热器氧化皮剥落堵塞过热管造成管壁超温爆管的问题,对锅炉管道爆口附近铁素体钢(T23/T91)管样的金相组织及氧化皮成分与结构进行分析,得到了氧化皮的生成及剥落机理,结果表明在高温运行状况下:氧化皮的生成速度取决于金属管壁温度和钢材的抗氧化性能;氧化皮的剥落主要取决于氧化皮与金属基体的温差及温度变化速率。从锅炉运行调整、化学清洗和加强检查等方面提出了预防和减少锅炉高温受热面管内氧化皮的形成及剥落的措施。这些防治措施可有效地减少因氧化皮形成及剥落而引起管束超温爆管的事故,提高了机组的可靠性。
Aiming at tube burst caused by overheat of tube results from wall tube blockage by scale spalling of superheater of 600 MW boiler of unit 2 in Chaozhou Power Plant,metallographic structure of the sample of ferritic steel tube（T23/T91） near the broken seam of boiler tube,composition and structure of the scale are analyzed,from which generation mechanism and spalling mechanism are concluded.The result shows that,under circumstance of operation at high temperature,generation speed of the scale is determined by wall temperature of metal tubes and oxidation resistance of the steel material,and scale spalling largely depends on temperature difference between the scale and the metal base as well as rate of temperature change.Prevention measures for generation and spalling of the scale in tubes at high temperature heating surface of the boiler are suggested in terms of adjustment of boiler operation,chemical cleaning and inspection strengthening.These preventive measures can effectively reduce accidents of tube burst caused by overheat of bundled tubes resulting from generation and spalling of scale.
出处
《广东电力》
2011年第3期52-55,共4页
Guangdong Electric Power
关键词
600MW机组
超临界压力锅炉
高温受热面
氧化皮产生
氧化皮剥落
爆管
600 MW unit
supercritical pressure boiler
high temperature heating surface
scale generation
scale spalling
tube burst
