摘要
现代大型火力发电厂给水泵通常采用机械密封方式,由于安装水平、运行调整等因素,给水泵密封水流量的代数和通常不为零,从而导致机组热耗上升。本文采用等效焓降法分析给水泵密封水流量对机组热耗的影响,并分析性能试验中给水泵密封水流量测量对试验不确定度的影响;同时对现场机组进行实测调整,控制给水泵密封水流量,达到降低机组热耗及性能试验不确定度的目的。
The feed pump designed in the large thermal power plant usually takes mechanical seal method. As a re- sult of the installation level, operation adjustment and other factors, normally the algebraic sum of seal water flow is not zero which leads the unit heat consumption rising. This paper uses equivalent enthalpy drop method to analyze the influence of seal water flow on the unit heat consumption and the performance test uncertainty. At the same time, by adjusting and mea- suring on the field units, control the seal water flow to reduce the unit heat consumption and achieve the performance test un- certainty.
关键词
机械密封
等效焓降
热耗
不确定度
mechanical seal
equivalent enthalpy drop method
heat consumption
performance test uncertainty
