摘要
针对某电厂125MW汽轮机在大修后出现调节级后压力和温度高、最大出力不足的现象,总结了可能出现的各种影响因素。经过高压缸揭缸检修,发现其调节级损伤严重,高压隔板的严重变形导致高压缸通流面积减小;同时性能试验结果显示调节级效率严重降低。经过详细的热力计算,分析出各环节对该机组调节级后压力升高及出力的影响,结果发现,高压缸隔板变形导致通流面积减小是影响调节级后压力升高的主要原因;调节级喷嘴面积及高压缸压力级通流面积的减小,导致了机组最大进汽量降低,使机组最大出力下降。经过变形修复,机组实际运行时调节级后压力和温度达到正常值,并能够带满负荷。分析方法和结果为以后其他机组出现类似问题提供了一些参考。
Aiming at the shortage of maximum pressure and temperature output downstream the regulation stage of an overhauled 125 MW steam turbine,different kinds of influencing factors that may arise are summarized.Through check by exposing the high-pressure cylinder,it is found that the regulation stage is damaged seriously with gross distortion of the high-pressure bulkhead resulting in reduced flow area in high pressure cylinder while performance test results show that the efficiency of regulation stage is reduced severely.After a detailed thermal calculation the impacts of various segments to pressure rise and capacity downstream the regulation stage of the unit are found by analyses.It is found that the deformation of high-pressure cylinder bulkhead may reduce the flow area and this is the main cause for pressure rise downstream the regulation stage.The reduction of jet area at regulation stage and of flow area at pressure stage in high pressure cylinder will lead to a cut of maximum unit output owing to that the maximum throttle flow of the unit is reduced.After restoration of the deformation,as the unit is put into practical running its pressure and temperature downstream the regulation stage could reach their normal values,and are able to bring the full load.Analytical methods and results could provide some references for future similar problems appeared in other units.
出处
《上海电气技术》
2016年第1期53-58,共6页
Journal of Shanghai Electric Technology
关键词
调节级
压力
出力
热力分析
调节级损伤
隔板变形
Regulation Stage
Pressure
Capacity
Thermal Analysis
Damage in Regulation Stage
Deformation of Bulkhead
