Do You Know How to Choose a Balance Valve?

For hydraulic adapters and stainless steel hydraulic hoses, we don't seem to worry about how to choose them. But for the balance valve, we may be entangled in which one is better. Therefore, we have summarized 18 precautions and application experience about balancing valve selection for your reference.

1. Generally speaking, low pilot pressure has better performance and stability than valve motion control, especially spring-like systems with large inertial loads.

2. For hydraulic motors, valves with high pilot pressure ratio can provide good dynamic control. However, due to the leakage of the motor, spring brakes, adjustable hose clamps and steel hose clamps have to be added to lock the load.

3. The valve with high pilot pressure ratio can improve the efficiency of the hydraulic system (reduce heat consumption), but reduces the stability and smooth movement.

4. Under normal circumstances, we should try our best to avoid applying balance valves in closed loop hydrostatic drive systems or closed loop hydrostatic transmissions, which will cause the system to overheat.

5. The balance valve is not a low-pressure working element. The use of large valves does not reduce energy consumption. The system pressure should generally be greater than 750psi (50bar).

6. It is recommended to install the valve closest to the actuator in order to prevent the failure of the pipeline from affecting the system to the greatest extent. The valve can be directly integrated into the actuator. The valve block is installed with a plate, which can be directly bolted to the installation surface of the cylinder/motor.

7. The minimum setting value of the balance valve is set to be 1.3 times the load pressure.

8. As with other stainless steel pipe fittings and copper pipe fittings, for the cartridge balance valve, turning the adjusting screw clockwise reduces the pressure setting, while counterclockwise increases it.

9. When the balance valve is selected, its size can be small, not large, because the valve's goal is to produce valve pressure drop.

10. We should choose a smaller pilot pressure ratio to ensure system stability. The smaller the pilot pressure ratio, the better the control performance.

11. Valves with a pilot pressure ratio of 10:1 can only be used in motor circuits or pilot check valve circuits that require a pilot pressure ratio of 10:1.

12. The balance valve will reset when it reaches 85% of the opening pressure.

13. The leakage of the balance valve tested under the reset pressure does not exceed 5 drops/min. When the valve setting value is set to 1.3 times the maximum load pressure, the maximum pressure will not exceed 77% of the setting value, so it can be regarded as a non-leakage component. The back pressure will counteract the pilot pressure. For valves without external ports, the increased valve setting value is still (1+pilot pressure ratio) × back pressure value.

14. Although the balance valve has an overflow function, it cannot be regarded as a complete overflow valve. If it is used as a pure overflow valve, its stability, noise and life will have problems.

15. Adding an accumulator on the pilot oil circuit can improve the stability of the system and make the pilot pressure more stable.

16. Adding an outlet throttle valve between the cylinder/motor and the balance valve can improve system stability.

17. Compared with the valve without external interface, the gain of the overflow performance curve of the balance valve with external interface is very high, which is similar to the direct-acting sequence valve. This makes the stability of the system using the balance valve with an external interface relatively low. However, if there are other components in the system that will cause the back pressure to change, this issue should be noted.

18. The pressure value of the balance valve must be set before it is installed in the system. This is not just for safety reasons. Once installed, it is extremely difficult to make precise settings. Only on rare occasions is it necessary to adjust after installation.

We hope that the above summary can help you. Follow us to learn more about hydraulic connectors and hydraulic hose repair clamps.