发电机密封油箱补排油装置改造及效果分析

RETROFIT OF REPLENISHING AND DISCHARGING DEVICES FOR SEAL-OIL TANK OF GENERATORS AND EFFECT ANALYSIS THEREOF

对于氢冷汽轮发电机组,无氢气外漏、保持发电机内的氢气纯度、避免发电机进油是保证其安全运行的3项重要指标,而发电机密封供油系统中的密封油箱补排油装置的可靠性是实现该3项指标的保证。针对沙角A电厂4号发电机密封油箱补排油装置存在的密封油箱同时补排油、油位控制品质下降等问题,对发电机密封油箱补排油浮球阀进行了技术改造。实际应用表明,改造后密封油箱油位均能够自动控制在理想状态,实现了密封油箱油位的自动化控制,大大提高了机组运行的安全可靠性。

Three important indices for ensuring safe operation of the hydrogen cooled turbo- generator sets are as follows： having no hydrogen leakage to the outside;keeping purity of hydrogen in the generator;and avoiding oil entering into the generator. The reliability of oil -replenishing and oil -dicharging device for seal -oil tank in the seal -oil supplying sysrem, however, is the guarantee to realize the above - mentioned three indices. Directing against the problems existing in the device of replenishing and discharging oil for seal - oil tank of generator no. 4 in Shajiao A Power Plant,such as discharging oil occurred at the same time of replenishing oil into the seal - oil tank,decreasing control quality of oil - level in the seal -oil tank,etc. ,the retrofit of floating - ball valves for replenishing oil into the tank and for discharging oil out from the tank has been carried out. Practical application shows that the oil - level in seal - oil tank after retrofit can accurately and automatically be controlled to the desired situation, realizing control automation of oil - level in the seal- oil tank, enhancing greatly the safety and reliability in operation of the unit.