How Several Throttle Valves Work

Throttle valve refers to a valve that controls or regulates the flow and pressure of a medium by changing the passage area. Throttle valve is mainly used for throttling in pipeline.

(a) Flexible throttle valve

The working principle of the flexible throttle valve relies on the valve stem to clamp the flexible rubber tube to generate the throttling effect. It is also possible to use the gas pressure instead of the valve stem compression hose. The flexible throttle valve has a simple structure, low pressure drop, and high reliability of operation. Insensitive to contamination, the working pressure range is usually 0.3-0.63 MPa.

(II) Overflow throttle valve

The overflow throttle valve is also a pressure compensation type throttle valve, which is formed by connecting an overflow valve and a throttle valve in parallel. The high-pressure oil at the inlet is partially passed through the throttle valve to the actuator, and the other part passes through the overflow port of the relief valve to the tank. The upper and lower pressure relief valves communicate with the pressure oil before and after the throttle valve. When the outlet pressure increases, the spool moves downward and closes the small overflow port. The overflow resistance increases and the inlet pressure increases, so the pressure difference before and after the throttle valve remains basically unchanged.

(III) Proportional Direction Throttle Valve

A proportional electromagnet is used instead of an ordinary electromagnet in an electromagnetic reversing valve to form a direct-acting proportional direction throttle valve. Due to the use of proportional electromagnets, the spool can not only be transposed, but also the stroke of the transposition can be continuously or proportionally changed, so that the flow area between the communicating ports can also be continuously or proportionally changed, so the proportional direction Throttle valve can not only control the direction of movement of the actuator, but also control its speed.