What are the classifications of hydraulic valves?
Hydraulic valves are hydraulic components used to control the pressure, flow and direction of liquids in hydraulic transmission. This article summarizes the classification of hydraulic valves.
Classification of hydraulic valves
1. Classification by purpose
Hydraulic valves can be divided into three categories according to their uses: directional control valves (such as check valves, reversing valves, etc.), pressure control valves (such as relief valves, sequence valves, pressure reducing valves, etc.), flow control valves (such as throttle Flow valve, speed control valve, etc.). These three types of valves can also be combined with each other to form a combination valve according to needs, so as to reduce pipeline connections, make its structure more compact, simple to connect, and improve efficiency. The more commonly used combination valves are composed of one-way valves and other valves, such as one-way pressure reducing valves, one-way sequence valves, and one-way throttle valves.
2. Classified by Manipulation
Hydraulic valves can be divided into manual valves, motorized valves, electric valves, hydraulic valves, etc. according to the operation method.
3. Classified by control method
(1) Fixed value or switch control valves include ordinary control valves, cartridge valves and stack valves.
(2) Electro-hydraulic control valves include electro-hydraulic servo valves, electro-hydraulic proportional valves and electro-hydraulic digital valves, which are a type of valve that combines hydraulic technology and electronic technology. Among them, the servo control valve is a valve that continuously controls the direction, pressure and flow of the liquid in the hydraulic system in proportion to the input signal (such as electrical, mechanical, pneumatic, etc.) and feedback; the proportional control valve is between It is a valve between ordinary control valves and servo control valves. It can continuously control the direction of liquid flow, pressure and flow in the hydraulic system in proportion to the magnitude of the input signal, but the control accuracy is not high. It is a kind of valve with both A control valve with a certain servo performance and a relatively simple structure; a digital control valve uses digital information to directly control the opening and closing of the valve port, thereby controlling the direction, pressure and flow of hydraulic oil in the hydraulic pump or system.
4. Classified by installation method
(1) Pipe connection The pipe valve adopts threaded connection, also known as threaded connection.
(2) Plate connection Install the valve components on a special connection plate.
(3) Integrated connection In order to make the structure compact and simplify the pipeline, the valves are arranged in a centralized manner, including integrated block type, stacked valve type and cartridge valve type.