MSIV先导阀无法开启故障分析及改进研究

Defect analysis and improvement of the MSIV pilot valve

针对田湾核电站主蒸汽快速隔离阀的电磁先导阀无法开启的故障问题,对电磁先导阀的弹簧力、电磁执行机构的电磁力等方面因素进行了全面的分析。通过直动式电磁铁静态特性试验获取了电磁执行机构的电磁力与工作气隙的关系,结合电磁先导阀机械行程与电磁执行机构行程匹配设定方法、电磁执行机构的温升特性以及环境温度,对电磁执行机构工作性能影响进行了多方面的改进试验,并进行了改进后的温升试验及额定工况的运行试验验证。研究结果表明:通过减小电磁执行机构工作气隙和降低电磁执行机构工作温度,电磁先导阀的开启可靠性得了到大幅提高,改进后的电磁先导阀未再出现无法开启或开启一段时间后意外关闭故障。

Aiming at the fail to open problem of the solenoid operated pilot valve of the MSIV in TNPS, the spring force of the pilot valve, the electromagnetic force of the electromagnetic actuator and other factors were researched. The relationship between the electromagnetic force and the working air gap of the electromagnetic actuator was obtained through the static characteristics of direct-acting electromagnet test, and some improvement work performance impact tests were done, combined with the mechanical stroke of the pilot valve and the adjust method of the working air gap of electromagnetic actuator, the temperature rise characteristics and the ambient temperature affect to the performance of the electromagnetic actuator, the temperature rise test and operation test under rated condition were done after the improvement .The results indicate that the opening reliability of the electromagnetic pilot valve can be greatly improved by reducing the air gap of electromagnetic actuator and the operating temperature of electromagnetic actuator, the improved electromagnetic pilot valve has not been unable to open or accidentally shut down after a period of time.