What are the performance requirements of the speed control valve in the hydraulic press?

1. The pressure difference of the four-column hydraulic machine into and out of the oil chamber means that the throttle is fully open. When the nominal flow is passed, the pressure difference between the valve in and out of the oil chamber is generally about 1mpa. If the pressure difference is too low, the pressure reducing valve part cannot perform pressure compensation on the throttle valve, thus affecting the stability of the flow.

2. Flow adjustment range. In general, the larger the flow adjustment range of a four-column hydraulic press, the better, and during adjustment, the flow changes uniformly and the adjustment performance is good.

3. Stable flow rate refers to the flow rate at which the speed control valve of the four-column hydraulic press can work normally, that is, the rate of change of flow rate is not more than 10%, and no flow interruption occurs. The stable flow of QF type speed control valve and QDF type one-way throttle valve is generally about 10% of the nominal flow.

4. Internal leakage is the flow rate from the oil inlet cavity to the oil outlet cavity at the fitting gap between the spool of the four-column hydraulic machine and the valve body when the pressure in the oil inlet cavity is adjusted to the nominal pressure when the throttle valve is fully closed, and the amount of internal leakage is required To be small. In addition, the four-column hydraulic press requires that the speed control valve is not easily blocked when it is working. The flow rate through the valve is less affected by temperature.