Air check valve
I. Introduction:
When the outlet valve of the H48Y air discharge check valve is opened and the feed pump starts, after the feed water reaches a certain pressure, the disc rises to a certain height under the action of the feed water pressure, pushing away from the valve seat, and the feed water flows out. At the same time, as the disc rises, it drives the connecting rod to rotate, toggling the vent valve disc to move the recirculation blade-type valve downward and close the vent. When the feed water flow decreases, the disc falls, pushing the connecting rod to open the vent valve disc and open the recirculation valve to maintain the minimum allowable flow of the pump. When the pump stops, the disc automatically falls to close the valve port channel, preventing high-pressure water hammer from damaging the water supply system. The air discharge check valve is mainly used at the outlet of feed pumps in thermal power plants. It works in conjunction with the pump's minimum flow recirculation valve to maintain the safe operation of the system.
II. Product Features:
1. This valve works in conjunction with the recirculation bypass valve to maintain the safe operation of the system.
2. The main disc moves up and down; when the medium flows backward, the channel is closed by means of the medium pressure and the spring action, at which time the bypass valve opens. When the main disc is fully open, the bypass valve closes.
3. The disc seal is made of stainless steel surfacing, which is wear-resistant, has strong scratch resistance, and provides reliable sealing.
4. The valve should be installed vertically.
III. Product Installation:
Installed on the outlet pipeline of the high-pressure feed pump of a thermal power unit, it prevents backflow of feed water and protects the feed pump. This valve works in conjunction with the pump's minimum flow automatic recirculation bypass valve. When the feed pump is under low load or the outlet valve is closed, the automatic recirculation bypass valve should be in the open position to ensure the safe operation of the pump. When the check valve opens, the recirculation bypass valve automatically closes. It is not suitable for media containing solid particles and with high viscosity.
IV. Component Materials:
Component Name | Material |
Valve body, positioning wheel, connecting flange, exhaust flange, flange cover | Carbon cast steel |
Guide shaft, fork, shaft sleeve, slider, discharge sleeve, exhaust disc | Stainless steel |
Bolts, studs | Chrome-molybdenum steel |
Bushing | Cast aluminum bronze |
Disc, disc body, disc shaft, connecting fork, nut | High-quality carbon steel |
V. Technical Parameters:
Nominal Pressure PN (MPa) | Shell Test Pressure Ps (MPa) | Working Pressure P (MPa) | Applicable Medium | Working Temperature (℃) |
20.0 | 30.0 | 20.0 | Water | ≤160 |
| Machinery & Equipment/Valves/Check Valves | |
