某核电厂汽轮机中压调节阀故障研究与处理

Failure Study and Treatment of Medium Pressure Control Valve of Steam Turbine in Nuclear Power Plant

为了妥善自主处理某核电厂汽轮机中压调节阀故障及查找原因,系统性梳理与分析了同类机组运行经验及当前机组的阀门改进项。采用现场试验的方法,分析故障机组阀门的试验数据,确认了液压油质、比例阀控制为非致因因素;分析在近期大修商运机组的新旧比例阀性能比对试验的数据,进一步确认了新比例阀在该机组上的工作性能弱于旧比例阀。通过分析在调试机组接入比例阀接口装置测量得到的压降数据和尝试调整减压阀定值,可复现与消除故障。结果证明了减压阀定值设定不当是导致阀门故障的原因。该研究为后序机组阀门故障处理提供了借鉴。

To deal with the failure of the medium pressure control valve of a nuclear power plant steam turbine properly and independently and find out the cause,the operating experience of similar units and the improvement items of the valves of the current units are systematically sorted out and analyzed.Using the field test method,the test data of the valve in the faulty unit is analyzed to confirm that the hydraulic oil quality and proportional valve control are non⁃causal factors;and the data of the old and new proportional valves in the recent overhaul of the commercial unit are analyzed to further confirm that the performance of the new proportional valves is weaker than the old ones in this unit.By analyzing the pressure drop data measured by accessing the proportional valve interface device in the commissioning unit and attempting to adjust the setting of the pressure reducing valve,it is possible to reproduce and eliminate the malfunction.The results demonstrated that improper setting of the pressure reducing valve rating is the ultimate cause of the valve failure.This study provides a reference for valve failure in later sequence units.