Reducing valves: device and principle of operation

2024 Author: Erin Ralphs | [email protected]. Last modified: 2024-02-19 11:42

Reducing valves are mechanisms that are designed to maintain low pressure in the discharged fluid stream. Most often, such tools are used in hydraulic drives, in which several devices are powered from one pump at once. In this case, pressure reducing valves normalize the pressure under which liquid is supplied to all consumers, that is, an excessively increased or, conversely, reduced pressure does not occur in the system. This device can significantly reduce the risk of damage to the main supply lines of the working fluid associated with excessive pressure inside the system.

This mechanism consists of the following parts:

• calibrated spring;
• ball;
• spool;
• damper;
• high pressure supply;
• internal cavities in the body for spool control.

Reducing valve: photo andoperating principle

The fluid that is supplied from the main line enters the internal control cavity and through a special annular slot between the spool and the body is fed into the hole associated with the entire mechanism system.

In the case when the pressure in the line rises, the ball inside the mechanism also rises, and the pressure in the control cavity decreases to normal. This hole is replenished with working fluid from other cavities, as well as from the hole of a small section of the damper. The spool can regulate the pressure in only two lines, blocking the channel for supplying the working fluid from the main system. Thus, this part increases the resistance to the passage of liquid, as a result of which the pressure in the cavity increases, which is determined by the force of the calibrated spring.

When the pressure in the system decreases, the spool moves under the influence of the spring, thereby increasing the annular gap between the two cavities. Reducing valves in this case change the pressure of the fluid supply in one of the holes.

Based on this, we see that the pressure level at the outlet remains unchanged and is maintained by the device at an optimal level, regardless of the pressure of the hydraulic line and the flow rate of the working fluid.

What should I do if the mechanism does not maintain normal water supply?

Sometimes it happens that pressure reducing valves are not able to provide all users with normal pressure. In this case, it should be adjusted. Each device, including the VAZ pressure reducing valve2109, has a special adjusting screw on the body, which affects the closing and opening of the spool in the system. With the right setting, you can achieve ideal values for the supply of working fluid.

Price

To date, the average cost of this device is 5-5.5 thousand rubles. The cheapest pressure reducing valves can be purchased for 1200-1300 rubles. The most expensive options cost about ten thousand.

Conclusion

So, we learned what the pressure reducing valve consists of, and found out how the position of the spool and ball affects the pressure in the internal cavities of the mechanism.