Flow control valves are designed to be used in pneumatic systems and sophisticated hydraulics. The valves include simple openings to advanced closed-loop electrohydraulic valves that adjust automatically when dealing with temperature and pressure. The main purpose of the valve in the hydraulic system is to regulate speed effectively.
These valves control the speed of the actuator by regulating the flow rate. Flow rate indicates the rate of energy that is transferred with any given pressure. Actuator speed determines the energy rate of transfer and speed is responsible for flow rate. Directional control valves, don’t deal with energy control but it directs the energy transfer at the place in the system and at the right time.
Flow Control Valves in Hydraulic Circuits
Orifices. They are the most primary method in controlling flow. The orifice is placed in series with the pump when used in controlling flow. It can be a drilled hole in the fitting.
Flow Regulators. They are more sophisticated compared to orifices. They have compensating abilities that provide closer control of the rate of flow under pressure conditions. The control accuracy can be 5% lesser with calibrated valves that operate in a given flow rate.
Bypass Flow Regulators. They flow in excess of flow rate comes back to the tank through a bypass port in this flow regulator. The flow rate is controlled effectively by throttling fluid across an orifice that is regulated by a compensator piston. Using a bypass regulator is more effective compared to a standard flow regulator.
Demand-compensated Flow Controls. With this, fluid is routed at an administered flow rate to the primary circuit. The bypass fluid can be used in specific functions for secondary circuits without affecting the first one. For this type of valve, there must be flow to the primary circuit.
Pressure-compensated, Variable Flow Valves. This type of flow control valve is equipped with an adjustable orifice that is placed in series with a compensator. The compensator automatically adjusts to different load and inlet pressures. These are available with integral overload relief valves and integral reverse-flow check valves.
Deceleration Valves. This type of valve is modified spring-offset, 2 way and cam-actuated valve that is used for decelerating a load controlled by a cylinder. A cam is attached to a cylinder load or rod that closes the valve slowly.
These are some of the types of flow control valves that are commonly used in hydraulic circuits. Understanding their functions and purpose will provide you with the knowledge of using them effectively.