The directional-control valve is one of the most fundamental and important components of any fluid power system. Directional control valves, as the name implies, are used to direct the flow of fluid through the system. The flow of fluid in the system is controlled by directional control valves. These valves control fluid flow in a system.
The Operation of Directional Control Valves
To handle the pressure in a system, directional control valves are used. Valves will change from fully open to fully closed or proportionally. This happens instantly, causing fluid to rapidly accelerate and decelerate, or, in the case of a proportional valve, it is modulated to ramp up and ramp down actuator acceleration and deceleration. This can be done manually or automatically using valve cycle settings. Directional control valves maintain fluid in a standby mode, preventing it from flowing from within the system until it is required to move and perform its intended function. When activated, directional control valves shift to perform the operation and then return to the neutral position when finished. This action happens instantly, causing the fluid to accelerate and decelerate.
A 2-way valve is the most basic directional control valve. These simply prevent or allow flow. A 2-way valve, as the name implies, has two ports called the inlet and the outlet. A water faucet is a great example of a 2-way valve and its simplicity. A water faucet's manual control allows or stops flow.
The designer looks for two primary characteristics when selecting a DCV: fluid ports and the number of positions. The valve ports allow hydraulic fluid to flow to and from other components. The number of positions indicates how many distinct flow paths a valve can provide.
How to Choose a Directional Control Valve
As follows, directional control valves are classified based on various characteristics such as maximum flow rate, maximum rated working pressure, number of ports, number of positions, actuating method used, fluid path, leakage rates, and so on:
Max Flow Rate/Max Rated Working Pressure: The maximum pressure required to complete the work in the process
Check valves are an example of a 2-way 2-position valve that is actuated by line pressure to allow fluid flow in one direction while blocking flow in the opposite direction. Shuttle valves are a type of 3-way 2-position valve that allows switching from two ports into a single common circuit.
Positions: There are usually two or three positions available. Forward, Neutral, and Reverse
The number of flow paths through which fluid can enter and exit the valve.
Actuation: The process by which the valve is cycled.
Every hydraulic system is unique. Choosing the right valves is critical to constructing and maintaining an efficient hydraulic system.
