VALVES FOR NUCLEAR APPLICATION
FROZEN SEAL GATE VALVES
- Supply includes Electric operated gate valves with the Electric actuator of 100NB nominal size and 200NB nominal size.
- Supplied the valve with Rotork Actuator – IQ Series.
- The principal sealing towards the exterior is assured by means of solidified sodium. The solidified region where the sodium is to be frozen to form the seal will be cooled by means of air by natural convection.
- Circumferential fins are provided on the valve stem guide to improve the heat transfer.
- After the frozen seal, there is a stuffing box, which acts as secondary seal and is easily accessible for replacement without disconnecting the valve from the circuit.
- Provision is made to fix the surface thermocouple to measure the temperature of the last fin.
- In order to avoid air entering and forming sodium oxides, a double ‘O’ ring suitable for service at 373 K (100°C) seal arrangement is incorporated after the frozen seal between the bonnet, stem and packing follower.