Features

It is a special quick-closing valve to protect the steam turbine generator set. It is designed to prevent the pressure in the turbine from suddenly decreasing when the turbine set is suddenly loaded, and the steam in the exhaust pipe and various heaters from flowing back into the turbine, causing the turbine blades rotating at a high speed of more than 3000 revolutions per minute to suddenly run in reverse, causing the turbine blades to be broken and the turbine generator to be damaged. It also prevents water hammer accidents caused by water leakage in the heater system pipeline. When the above situation occurs, the valve can be quickly closed within 0.5 seconds.

Structural features

1. The pneumatic check valve uses compressed air to push the piston in the cylinder, which pushes the fork, which in turn drives the rocker shaft to rotate to open the valve. The air source is cut off by the solenoid valve, and the spring pushes the piston back to close the valve.
2. The sealing surface of the valve disc and valve seat adopts the latest surfacing material, which has strong wear resistance and abrasion resistance.
3. Adopt high-performance new type of filler, which ensures reliable sealing and easy and flexible operation.

Product standards

1. Design standards: According to JB/T 3595-20, 3595-2002 and NB/T 47044-2014. (The standard for exhaust check valves for steam turbines has not yet come into effect)

2. Design standards: ASME B16.34-2013

Nominal pressure: PN16-PN420 (150LB-2500LB)

Nominal thread diameter: DN50-DN500 (2°-20°)

Main material:

1. WCB

2.ZG20CrMo, ZG15Cr1Mo1V

3. ASTM A216 WCB

4. ASTM A217 WC6、ASTM A217 WC9

Operating temperature:

1.WCB: -29°C~425°C

2. Alloy steel: -29°C~540°C, -29°C~570°C

Applicable medium: water, steam, etc.

Connection method: flange, welding

Transmission mode: pneumatic, hydraulic