The regulating valve is generally composed of an actuator and a valve. According to the power used by the actuator, the regulating valve can be divided into three types: pneumatic, electric, and hydraulic, that is, pneumatic regulating valves with compressed air as the power source, electric regulating valves with electricity as the power source, and electro-hydraulic regulating valves with liquid medium (such as oil, etc.) pressure as the power source.

The regulating mechanism has a straight-through single-seat valve, in which there is only a valve core and a valve seat in the valve body. The valve stem drives the valve core up and down to change the relative position between the valve core and the valve seat, thereby changing the fluid flow. Its main advantage is small leakage.

The regulating mechanism has a straight-through double-seat valve, in which there are only two valve cores and valve seats in the valve body. The valve stem drives the valve core up and down to change the relative position between the valve core and the valve seat, thereby changing the fluid flow. Since the fluid pressure acts on the two valve cores, the unbalanced forces offset each other a lot, so the allowable pressure difference is large.

The valve body of the sleeve valve is similar to the general straight-through single valve seat, and there is a cylindrical sleeve inside the valve, also called a cage. The valve core can move up and down in the sleeve, guided by the sleeve. The valve core moves in the sleeve, changing the orifice area of the sleeve, forming various characteristics and realizing flow regulation. Since the sleeve valve adopts a balanced valve core structure, it can reduce the unbalanced force of the medium on the valve plug, and with sufficient valve plug guidance, it is not easy to cause the valve core to vibrate.