Flow control valves are used to control the speed of the actuator. In a pneumatic system, the speed of the pneumatic cylinder may require to be controlled depending upon the application. Use of flow control valve meets the requirement of controlling the speed of the pneumatic cylinder. Flow control valves are also called as speed controller or Pressure reducing valves.
There are two types of speed controller. One is in-line type speed controller and another type is direct mounted type. The direct mounted speed controller thread is fitted into the air cylinder port. The knob provided at the speed controller controls the flow of the air. These speed controllers can be either Meter-in type or Meter-out type speed controller. In meter-in speed controller the incoming air is controller. That means the flow of incoming air into the cylinder is regulated to achieve the desired speed of the air cylinder. In meter-out speed controller, the flow of outgoing air from the cylinder out port is controlled to achieve the desired speed of the air cylinder.