200MW汽轮机夹层、法兰加热装置运行应用及优化

汽轮机高压缸设置汽缸夹层及法兰加热装置是为缩短机组启动时间、减小汽机内外缸、上下缸温差、高压缸差胀以及停机时使汽缸温度降至最低。夹层和法兰加热装置在机组启停以及运行中具有较大的作用,但也要运用适当。而茂名热电厂200MW机组投入运行以来,机组存在启动时间比厂家给出的参考启动时间长,且在滑参数停机时高压内缸温度比主汽温度高30～40℃左右。为此,文章主要阐述茂名热电厂200MW机组在经过了多次启停过程中投退夹层及法兰加热装置的操作步骤进行分析和总结,不断完善操作方法,大大缩短了机组启动时间及停机时使高压缸的缸温更接近主蒸汽温度或比主汽温度低,并对容易发生的运行异常进行了分析。对同类型机组汽缸夹层及法兰加热装置运行有一定的指导意义。

The high pressure cylinder of steam turbine is equipped with cylinder interlayer and flange heating device in order to shorten the start-up time of the unit,reduce the temperature difference between the inner and outer cylinders of the turbine,the temperature difference between the upper and lower cylinders,the differential expansion of the high pressure cylinder and the minimum cylinder temperature during shutdown.Sandwich and flange heating devices play an important role in the start-up,shutdown and operation of the unit,but they should also be used properly.Since the unit was put into operation in Maoming Thermal Power Plant,the start-up time of the unit is longer than the reference start-up time given by the manufacturer,and the temperature of the high pressure inner cylinder is about 30℃higher than that of the main steam when the sliding parameters are stopped.For this reason,this paper mainly expounds the operation steps of the 200MW unit in Maoming Thermal Power Plant during the start-up and shutdown process,analyzes and summarizes the operation steps of the interlayer and flange heating device,and constantly perfects the operation method.The start-up time and shutdown time of the unit are greatly shortened,and the cylinder temperature of the high pressure cylinder is closer to or lower than that of the main steam,and the abnormal operation which is easy to occur is analyzed.It has certain guiding significance for the operation of cylinder interlayer and flange heating device of the same type of unit.