Pilot-operated pressure reducing valves are useful because they allow small and easy-to-operate feeds to control higher operating forces. It's even useful when solenoids are used to operate pilot-operated pressure reducing valves. For all operating conditions of the directional control valve (DCV), a minimum oil pressure needs to be ensured. Pilot signals are used to operate pressure control valves such as unloading valves, pressure reducing valves, sequence valves.

1. How to use a pilot-operated pressure reducing valve?

Pilot-operated pressure reducing valves are necessary to control and actuate large valves that would otherwise be relatively large in size relative to the actual valve. In other words, a larger magnetic force is required, which is practically infeasible. A pilot operated pressure reducing valve is a smaller size valve that controls a limited flow control feed to a separate pilot operated pressure reducing valve. Typically, this single valve controls the high pressure or high flow supply in the fluid control system.

Second, the control technology of the pilot pressure reducing valve:

The control technology of directional control valve can be divided into two categories: 1. Direct control unit 2. Indirect control unit

(1) Direct control unit

Direct control means actuation by oil pressure on a valve with a single large spool.

(2) Indirect control unit

The indirect control mechanism consists of two parts.

·A pressure oil controlled directional control valve.

A direct-controlled directional control valve is usually called a pilot valve, mainly using a solenoid valve as the actuator, as shown in the following figure.

How to use the directional control technology of the pilot-operated pressure reducing valve? (Fig.

Valves such as 3/2, 4/2 directional control valves are driven by solenoid valves, which in turn control the main valve. Therefore, these valves are called pilot valves and the controlled valves are called main valves. Since hydraulic presses operate at medium to high pressure, sometimes larger size direct acting control valves may require greater actuation force. In the case of a pilot-controlled directional control valve, the main valve spool is operated by oil pressure directed to the spool by a pilot-operated pressure reducing valve.