双流给水泵机组汽缸的结构性能研究

Study on Structural Performance of Cylinder in a Double-Stream Feed Pump Unit

与二次再热主机配套的给水泵汽轮机,相比于与一次再热主机配套的给水泵机组,其进汽参数有大幅提升。以某一电厂1 000MW等级全容量双流给水泵汽轮机的汽缸为例,通过三维有限元分析手段,研究了1 000MW等级全容量双流给水泵汽轮机汽缸在不同参数下的结构适应性。研究结果显示,相比于工作压力,工作温度对双流给水泵机组汽缸的结构影响更明显。进排汽温差越大,蒸汽室与进汽缸法兰接合面的密封性越差,排汽缸靠近垂直法兰处的斜撑板强度也越差;排汽温度越高,动静部件偏心越严重。从强度、密封及部件偏心的角度出发,论述了不同的汽缸结构可适用的工作参数范围,为1 000MW全容量双流给水泵汽轮机的开发设计提供参考。

The inlet steam parameters in feed pump steam turbine matched with double-reheat unit are much higher than that matched with single-reheat unit. Taking the cylinder of the 1 000 MW full capacity double-stream feed pump unit in a power plant as an example, the structure adaptability of the cylinder was studied by means of three-dimensional finite element method. The results showed that compared with the working pressure, the working temperature had more obvious influence on the structure of the cylinder. The higher the inlet and outlet temperature difference was, the worse the flange tightness in the steam chamber and the inlet cylinder would be, and the worse the strength of the inclined brace plate near the vertical flange would be. The higher the exhaust temperature was, the more serious the decentration of the rotation and stationary part would be. From aspects of strength, sealing and decentration, the applicable working parameters range of different cylinder structures was discussed. The research results can provide reference for the design and development of 1 000 MW full capacity double-stream feed pump unit.