炉水循环泵电机腔室温升异常的原因分析及对策

Analysis and Countermeasure on Abnormal Temperature Rising of Boiler Circulating Pump

某新建电站超临界锅炉在调试、投运初期,经常出现炉水循环泵电机腔室温升较快和温度较高等现象。经过剖析,发现温升异常的原因是:在超临界锅炉运行中,储水箱是炉水内污垢聚积的地方,而该厂炉水泵的布置和该泵的内部结构都使储水箱水中污垢能顺利地进入到该泵电机腔室内。该污垢堵塞了电机腔室内冷却水滤网和绕组内的流通截面,当启动该泵时,泵内冷却水流量减少,影响了泵内的散热,从而使泵电机腔室内温升异常,泵内温升又加剧了该泵内部高分子轴瓦的损坏。针对上述原因,采取的具体方案有:加强炉水品质监管、停炉时清洗泵内部、设立排污管、改造泵内设计及储水箱结构等。事实证明,这些解决方案是正确有效的。该经验对其他电厂有较高的借鉴价值。

The temperature of electromotor cavity of boiler circulating pump on supercritic boiler always rises abnormally in a newly built power plant at the early debugging days.With detailed analysis and strict reasoning,found the reason is that： the water cabin of supercritic boiler is a place where dirt was collected.The position of water cabin and the structure of pump,assisted by vibration of boiler,help the floating dirt deposited in the water of water cabin slide into electromotor cavity.Dirt deposited in electromotor cavity blocked the filter of pump,reduced the quantity of cooling water,thus rised the temperature of electromotor,quikened the abrasion of electromotor compound bearing.Followed the analysis,several countermeasures were taken or advised,such as potentiate the inspection of quality of boiler water,clean up the filter and electromotor cavity of the pump when boiler stopped,add a limber hole under the water cabin to let dirt out,improve the design of pump impeller to prevent dirt from sliding into electromoter cavity,etc.Some of which had been proven to be correct.The experience can be used for reference to the similar power plant.