[Cartridge Check Valves]
A Check Valve allows fluid flow only in one direction, and does not allow the reverse flow. It can be used on the export of hydraulic pumps, in order to prevent fluid backflow; separated the link between the Circuit, in order to interfere with each other; parallel to the sequence valve, pressure reducing valve, throttle and Speed Control Valve parallel to form a Check Sequence Valve, check pressure reducing valve, check throttle speed control valve and so on.
To choose the Check Valve should according to different application place, conform the opening pressure. If be used as back-pressure valve, generally the opening pressure should be higher; if just use as control the fluid to one way flow, can choose the lower opening pressure check valve.
Check Valves are main used on:
1. Mounted on export oil port of the hydraulic pump, in order to prevent a sudden increase of the system pressure to damage the hydraulic pump. To prevent oil back to the oil tank, when the pump stop working.
2. Mounted on the back to Circuit as a back-pressure valve.
3, and combined with other valves to check control valves.
[Type Of Check Valves]
Tubular Check Valves,Normal Check Valves,Reverse Check Valves,Hydraulic Operated Check Valves(Internal Leakage,Outer Leakage)
[Pilot Operated Check Valve]
A pilot operated checkvalve is used to keep a part of the system free from internal leakage for example a hydraulic cilinder or motor. A very good example is the application of the pilot operated checkvalve on the cilinder of the outrigger legs of a crane. The cilinder is connected to port B of the checkvalve. When oil is supplied to port A the oil can flow freely towards port B and to the cilinder. When the leg has to be retracted oil is supplied to te rodside of the cilinder. The pressure at the rodside of the cilinder is used as pilot pressure on port Z for opening the checkvalve. Now the oil can flow back from port B to port A. The pressure at port Z needed to open the checkvalve against the cilinderpressure behind the main valve is about 1/3 to 1/10 (called the opening ratio) of the cilinderpressure.
Features:
1.Light weight and compact size
-Combining several functions into a single manifold may save valuable space and weight, often occupying only 10% to 20% as much volume as conventional line-mounted systems plumbed with fittings, hose, and tubing.
2.Leakage prevention
-Because a valve package eliminates so many connections, system leakage potential is reduced drastically.
3.Efficiency for the system
-Valve packages that eliminate interconnecting lines and fittings lead to higher overall system efficiencies
4. Convenience and Serviceability
-Being more compact, valve packages sometimes can be mounted where they are less susceptible to external damage.
-Cartridges usually can be removed and replaced quickly without disturbing any external plumbing.
5. Aesthetics and Economy
-A clean design will not affect performance, but a good-looking machine on the dealer's sales floor in a competitive market can be an advantage to the OEM.
-On many systems, the cost of a custom valve package ,can be equal to (or less than) that of a system with individually plumbed components.
|
