600MW大抽汽量汽轮机低压缸结构优化

Structure Optimization of Low Pressure Cylinder of 600MW Steam Turbine with Large Extraction Capacity

随着热电矛盾加剧,600MW汽轮机中低压缸连通管抽汽量增大,对低压内缸的强度和气密性的要求更高,尤其低负荷下,强度和气密性问题更加严重。为了解决这个问题,对低压缸原蜗壳结构的铸铁内缸进行了结构优化,解决了抽汽量增加后低压缸进口温度升高带来的强度和汽密性问题,以及低压蜗壳流速偏低问题。采用有限元方法核算了优化后汽缸的的强度、汽密性等各项指标,均满足设计要求。

With the intensification of thermoelectric contradiction,the amount of steam extraction from connecting pipes of low-pressure cylinder in 600MW steam turbine increases,which requires higher strength and tightness of low-pressure cylinder,especially under low load.In order to solve this problem,the structure optimization of the cast iron inner cylinder with the original volute structure of the low-pressure cylinder is carried out,which solves the problems of strength and air tightness caused by the increase of inlet temperature of the low-pressure cylinder after the increase of steam extraction and the low flow rate of the low-pressure volute.The strength,air tightness and other indexes of the optimized cylinder are calculated by finite element method,which meet the design requirements.