主蒸汽隔离阀执行机构液压系统超压分析

Analysis and Solution of Overpressure Issue of Main Steam Isolation Valve of Expansion Project

秦山核电厂二期扩建工程的主蒸汽隔离阀执行机构在调试和运行中经常出现超压现象。通过对执行机构中氮气随温度的变化情况进行分析可知,超压的根本成因是:蓄能器活塞未设置温度补偿间隙,液压油随温度膨胀后,蓄能器无膨胀空间导致超压。提出了在超压发生时的临时处理方案,设计了主蒸汽隔离阀泄压模块并现场应用,成功解决了主蒸汽隔离阀执行机构超压问题。

The overpressure problem frequently occurred in the commissioning and operation of main steam isolation valve(MSIV) actuator of Qinshan Phase II expansion project.The analysis of the change of the nitrogen with the temperature found that the fundamental cause of the problem is as follows:there is no temperature compensation space for the accumulator plunger,and the hydraulic oil expanded with the change of temperature,and there is no space for accumulator to expand.A temporary scheme for overpressure problem is proposed,and a pressure relief device is designed and applied in real situation.The overpressure problem of MSIV actuator is solved successfully.