Selection requirements for control valves in hydraulic cylinders

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Release time:

2023-05-30

The selection of control valves in hydraulic cylinders can have a significant impact on their rationality. When choosing a control valve, there are two main considerations: the first is the selection of proportional directional valves, and the other is the selection of imported pressure compensators. Let's take a look at the specific content together.
Usually, we can combine different valve components as needed to use them together. For example, we can combine the throttle control proportional directional valve and the constant pressure reducing valve of the hydraulic cylinder to form a pressure compensation proportional directional flow valve. The controlled flow rate of this flow valve mainly depends on the input electrical signal and is not affected by changes in oil supply pressure and load pressure. The pressure difference value of a constant pressure reducing valve is usually 1. OMPa.
After determining the pressure difference, the flow rate of the hydraulic cylinder proportional directional valve can be determined as follows: the input signal corresponding to the actual maximum flow rate through the proportional directional valve should be close to 90% of the rated input signal, and the input signal corresponding to the actual minimum flow rate through the proportional valve should be greater than the dead band of the proportional directional valve. This not only improves the resolution of traffic, but also avoids the occurrence of crawling problems.
So, what considerations should be taken when choosing an imported pressure compensator? At present, the inlet pressure compensator of hydraulic cylinders mostly uses two way and three way structures, with two way being the most common. However, it should be noted that the normal operation of this type of compensator requires a minimum control pressure difference in order for the differential pressure reducing valve to have a differential pressure reducing effect.
If the executing component is a negative load, then this effect will be lost. To prevent such problems, we can use a balance valve with a back pressure function, which can ensure that the pressure difference at the proportional valve port does not change with load fluctuations.

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