Hydraulic control valves are widely used devices in fluid control systems. The following is a detailed introduction to their principle and structure:

I. Working Principle

A hydraulic control valve is a type of valve that uses the pressure of the pipeline medium as the driving force to open, close and regulate. It uses the pressure of water in the pipeline network to control the opening, closing and opening degree of the valve. It is an automatic valve that saves both manpower and energy.

Specifically, the working principle of a hydraulic control valve mainly relies on the pressure difference △P between the upstream and downstream as the driving force, which is controlled by a pilot valve to enable the diaphragm (or piston) to perform hydraulic differential operation. When the pressure water entering the control chamber above the diaphragm (or piston) is discharged into the atmosphere or the downstream low-pressure area, the pressure value acting on the lower part of the disc and below the diaphragm is greater than the pressure value above, thereby pushing the main valve disc to the fully open position. Conversely, when the pressure value in the control chamber is between the inlet pressure and the outlet pressure, the main valve disc is in the regulating state. The pilot valve can open or close its own small valve port by changing the downstream pressure, thereby altering the pressure value in the control chamber and further controlling the regulating position of the main valve disc.

Ii. Structure

The hydraulic control valve is mainly composed of the valve body, valve core, valve seat, regulating mechanism, transmission device, etc. The following is a detailed introduction to each component:

Valve body: The main body of the entire valve, with channels inside that are connected to the pipeline.

Valve core: The core component of the valve, which can move up and down to change the opening degree of the channel, thereby regulating parameters such as flow rate and pressure.

Valve seat: The base of the valve core, connected to the pipeline, ensuring that the valve core can fit tightly when closed to prevent medium leakage.

Regulating mechanism: A mechanism used to adjust the position of the valve core. It can change the position of the valve core through rotation or lever movement, thereby achieving precise control of parameters such as flow rate and pressure.

Transmission device: A device used to transmit power and motion, which can be in the form of electric, pneumatic or hydraulic, etc. The transmission device transmits external power to the valve core, enabling it to move in the predetermined manner.

In addition, hydraulic control valves may also include attached components such as conduits, needle valves, ball valves and pressure gauges, which vary depending on the type and application of the valve.

In conclusion, hydraulic control valves have the functions of regulating parameters such as flow rate, pressure and liquid level, and have been widely applied in fields such as petroleum, chemical engineering, power, metallurgy and water conservancy. Understanding their working principles and structures helps to better use and maintain these devices.