Counterbalance Valves

[Haihong Hydraulics’ Counterbalance Valve]
Haihong hydraulics has two types Screw-in Cartridge Counterbalance valves:
1)3-Port Non-vented ,Cartridge Counterbalance valves
2)3-Port Atmospherically Referenced, Vented Counterbalance Valves

Also we have Bi-directional Counterbalance Valves for you choose.
Screw-in Hydraulic counterbalance valve, Size from 08 to 16, Flow from 38LPM to 230LPM
and Bi-directional Counterbalance Valves, Size from 08 to 20,Flow from 38LPM to 140LPM
For more details, please feel free to contact us for more information.

[ Cartridge Counterbalance Valves]
Counterbalance valves are normally-closed , primarily used to maintain a set pressure in part of a hydraulic circuit, usually to counterbalance a weight or external force or counteract a weight such as a platen or a press and keep it from free-falling. The valve's primary port is connected to the cylinder's rod end, and the secondary port to the directional control valve. The pressure setting is slightly higher than that required to keep the load from free-falling.

When pressure fluid flows to the cylinder's cap end, the cylinder extends, increasing pressure in the rod end, and shifting the main spool in the counterbalance valve. This creates a path which permits fluid to flow through the secondary port to the directional control valve and to reservoir. As the load is raised, the integral check valve opens to allow the cylinder to retract freely.

If it is necessary to relieve back pressure at the cylinder, and increase the force at the bottom of the stroke, the counterbalance valve can be operated remotely.

Counterbalance valves are usually drained internally. When the cylinder extends, the valve must open and its secondary port is connected to reservoir. When the cylinder retracts, it matters little that load pressure is felt in the drain passage because the check valve bypasses the valve's spool.

The counterbalance valve is normally located in the line between a directional control valve and the outlet of a vertically mounted actuating cylinder which supports weight or must be held in position for a period of time. This valve serves as a hydraulic resistance to the actuating cylinder. For example, counterbalance valves are used in some hydraulically operated forklifts. The valve offers a resistance to the flow from the actuating cylinder when the fork is lowered. It also helps to support the fork in the UP position. Counterbalance valves are also used in air- launched weapons loaders. In this case the valve is located in the top of the lift cylinder. The valve requires a specific pressure to lower the load. If adequate pressure is not available, the load cannot be lowered. This prevents collapse of the load due to any malfunction of the hydraulic system.

In fact a counterbalance valve is an improved pilot operated check valve. An important and major difference between these two valves is:
- the opening pressure of a pilot operated check valve depends on the pressure (applied by the load) behind the valve;
- the opening pressure of a counterbalance valve depends on the spring pressure behind the valve.
The dynamic performance of a balance valve is many times better than the dynamic performance of a pilot operated check valve

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.