factory low price Ma Series Sliding-Stem Control Valve - PV48 vacuum breaking valve – Convista

Specifications

Type: nuclear power vacuum breaking valve

Model: ZKPHF41F-150 150Lb, ZKPHF21F-300 300Lb

Nominal Diameter: DN 20-50

The product is used for AP1000 unit as equipment negative pressure suction to prevent its excessive low pressure from damaging the equipment.

1.With spring type vacuum decompression, the vacuum breaking valve features easy constant pressure and repairing and convenient installation. The valve is designed as per pressure level and its design pressure is bigger than its maximum working pressure under operation environment temperature. The valve core is opening and closing part of the valve and O-type seal ring is installed in groove of the valve core to constitute sealing part of the valve core. When the valve seals, O-type seal ring contacts sealing surface of the valve seat; when valve jumps and discharges, O-type seal ring leaves sealing surface of the valve seat. When the valve core blows back, spring stretches and opening and closing part goes up along guiding hole of the valve seat; when the valve core opens, spring compresses and opening and closing part goes down along guiding hole of the valve seat.

2.The vacuum breaking valve, an automatic valve, requires no additional drive when it is put into operation. At normal working state, the joint force of spring and medium exerted on valve disc presses the valve disc towards the valve seat to make the sealing surface cling and seal; when medium pressure drops to specified vacuum value (i.e. negative pressure up to setting pressure), spring is compressed, valve disc leaves valve seat, external air enters and system pressure boosts; when system pressure rises to working value, the spring pulls the valve disc towards the valve seat and sealing surface clings again to return to normal working state.