Z641H pneumatic gate valve
Structural principle
With 0.4 ~ 0.6MPa (gauge pressure) purified compressed air as the working pressure, push the piston, drive the ram to be perpendicular to the fluid displacement, to achieve the purpose of opening and closing the valve. Clever design of double-layer cylinder and buffer mechanism
How it Works
1, gate valve before opening stage: the upper cylinder piston (hereinafter referred to as the upper piston) and the lower cylinder piston (hereinafter referred to as the lower piston) at the same time force, the valve stem in the upper and lower piston push, with a single piston nearly twice the lifting force to overcome the maximum static friction between the ram sealing surface and the valve body sealing surface, drive the ram to rise. Compressed air from the lower chamber of the upper cylinder, through the specific channel set in the partition, through the connecting tube, to the lower chamber of the lower cylinder, pushing the upper and lower piston to work at the same time. The gas in the upper air chamber of the lower cylinder passes through another specific channel arranged in the separator. Unimpeded discharge from the outside of the cylinder.
2. After the gate valve is opened, the lower piston runs to the upper dead point after the gate is slightly opened, and the gate continues to lift under the drive of the upper piston until it is fully open.
3. Before the gate valve is closed: Under the push of the upper piston, the gate leaves the fully open position and begins to fall.
4. The later stage of gate closure: when the upper piston touches the lower piston boss and drives the lower piston to continue to fall together, due to the obstruction of the intake channel of the upper air chamber of the lower cylinder and the exhaust channel of the lower air chamber of the lower cylinder, the downward speed is obviously slowed down, and the entrance to the gate is lowered to the fully closed position. Slow down the impact of the gate, can close the valve by itself, and does not make the valve plate wedge too tight, at the same time, but also protect the sealing surface, from violent impact and damage.
Flexible and reliable pneumatic-manual conversion mechanism, the pneumatic - manual conversion mechanism installed in the upper part of the cylinder head, in any position of the gate valve opening and closing process, it can be very convenient to turn the operating handle, directly from pneumatic to manual or from manual to pneumatic operation mode of conversion, the conversion operation handle adopts the positioning pin type self-locking design, after the handle is positioned, reliable and calm. When the solenoid valve and its control circuit or the air supply system fails, it can be quickly converted into the manual operation state without other auxiliary tools, to ensure the normal operation of the line and avoid accidents. Before the self-control system of the new project is not completed, this series of gate valves can be used reliably as manual gate valves, and the action is flexible and light.
The closing time of the valve can be adjusted by adjusting the buffer mechanism installed on the partition board, and the closing time of the gate can be adjusted within a certain range.