What are the classifications of directional control valves?
Hydraulic valves are used to control the flow direction of oil in a hydraulic system or to adjust its flow rate and pressure. As a type of hydraulic valve, directional control valves use the replacement of flow channels to control the flow direction of oil. The types of directional control valves include check valves, hydraulic control check valves, reversing valves, stroke reduction valves, liquid filling valves, shuttle valves, etc.
(1) According to the flow direction of the fluid in the pipeline, if the fluid is only allowed to flow in one direction, such a valve is called a one-way control valve, such as a one-way valve, a shuttle valve, etc.; a control valve that can change the direction of the fluid flow is called a reversing valve, such as the commonly used two-position two-way, two-position three-way, two-position five-way, three-position five-way, etc.
(2) According to the control method, it can be divided into solenoid valve, mechanical valve, air control valve and human control valve. Among them, solenoid valves can be divided into single and double electric control valves; mechanical valves can be divided into ball valves, roller valves, etc.; air control valves can also be divided into single air control and double air control valves; human valves can It is divided into two types: manual valve and foot valve.
(3) According to the working principle, it can be divided into direct-acting valve and pilot valve. The direct-acting valve is a valve that directly realizes the reversing requirements by manpower or electromagnetic force or pneumatic force; the pilot valve is composed of two parts: the pilot head and the valve body. The pilot head piston drives the valve stem inside the valve body to achieve direction change.
(4) According to the working position of the reversing valve stem, the valve can be divided into 2way and 3way valves.
(5) According to the number of air holes on the valve, it can be divided into 2port, 3port and 5port valves.