某核电站闭式冷却水泵轴承润滑问题分析

Analysis of Lubrication Problems of Closed Cooling Water Pump Bearings in a Nuclear Power Station

国内某核电站常规岛闭式冷却水泵正常运行工况下,多次出现泵两端轴承温度快速上涨或轴承长期保持较高温度运行等问题。通过对轴承室解体检查,发现轴承室内油脂过多、油脂发黑等问题。通过分析,确定缺陷主要原因为润滑脂加脂量与加脂周期设定不合理以及轴承室设计不合理,导致多余的旧油脂无法排出。这些问题导致泵轴承长期处于不可靠的运行状态,对核电站常规岛闭式冷却水泵稳定运行造成影响。文章对该轴承润滑问题进行根本原因分析,提出泵两端轴承温度异常的处理办法。通过制定润滑脂加脂量的优化方案,连同泵厂家重新设计新轴承室并增加排油方案,有效地解决了轴承温度异常的缺陷。

Under the normal operating conditions of a conventional island closed cooling water pump in a domestic nuclear power station,problems such as rapid rise in temperature of the bearings at both ends of the pump or long-term operation of the bearings at a relatively high temperature have repeatedly occurred.Through the disassembling inspection of the bearing chamber,problems such as excessive grease and blackened grease in the bearing chamber were found.Through analysis,it was determined that the main reasons for these defects are the unreasonable setting of grease adding amount and grease adding cycle and the unreasonable design of bearing chamber,which cause the excess used grease cannot be discharged.These problems led to long-term unreliable operation of the pump bearing and affected the stable operation of the conventional island closed cooling water pump in nuclear power plants.In this paper,the root cause of the bearing lubrication problem is analyzed,and solutions for abnormal bearing temperature at both ends of the pump are proposed.The abnormal temperature defects of the bearings were effectively dealt with by working out the optimization scheme of the amount of grease added,and by redesigning the new bearing chamber and oil discharge scheme together with the pump manufacturer.