Normal Problems and Countermeasures of the Main Steam Isolation Valve

The main steam isolation valve (MSIV) which is one of the critical equipment for nuclear power plants, should keep open normally and shut down quickly within 5 seconds under emergency conditions. The MSIV in a nuclear power plant have repeatedly encountered problems such as open failure, low oil pressure, and frequent pump movements during commissioning and operation, which restricted the main line of commissioning and laid a major hidden danger for the safe and stable operation of the unit. Through a series of countermeasures, the above problems have been successfully resolved, which provide good experience feedback for the operation, maintenance and localization of the MSIV. Restrict the main line of commissioning and lay a major hidden danger for the safe and stable operation of the unit. (authors)