HYDRAULIC PRESSURE REDUCING VALVES
Hello everyone,
In today’s blog post, we will briefly talk about hydraulic pressure reducing valves. These valves are sometimes confused with pressure relief valves; however, they are actually quite different. Enjoy the reading!
As we know, pressure relief valves are used to protect the system and to limit the maximum system pressure. When the system pressure exceeds the set value, the pressure relief valve is activated and directs the fluid back to the tank. In other words, it is a normally closed valve that remains on standby. (Hydraulic diagram on the left)
Pressure reducing valves, on the other hand, are normally open valves used to reduce the pressure in a downstream or sub-circuit of the system. (Hydraulic diagram on the right) In a hydraulic system, there may be sub-systems operating under different pressure levels, and this is where pressure reducing valves are required.
These valves sense the inlet pressure and close at the outlet to prevent the pressure from exceeding the desired value. In order to reduce pressure, the flow must be restricted, and pressure reducing valves perform exactly this function. They are especially used in pilot-operated directional control valves, where the pilot pressure is relatively low, allowing the required lower pressure to be obtained. Additionally, they can be used in applications where it is necessary to limit cylinder force.
Below, a cross-sectional view of a pilot-operated pressure reducing valve is shown. The pressure in the P line is high, while the pressure in the A line is the pressure we want to reduce. When the pressure in the A line reaches the set value of the pressure reducing valve, the spool moves and restricts the flow, allowing the oil to return to the tank through the drain line. As mentioned, these valves operate based on the principle of restricting flow in order to reduce pressure.
As Hidros Group, our product range includes pressure reducing valves that can be used in modular as well as valves that can be mounted directly in-line. You can always contact us for more detailed information!
Images are used for training purposes.
Sources:
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