How Hydraulic Valves Work How Hydraulic Valves Work
All hydraulic machinery requires hydraulic fluid in order to function, and hydraulic valves are the controlling device in this process. It is the valve that determines the pressure and precision of the fluid's movement.
The moving part of the hydraulic valve is often referred to as a spool, as it resembles a spool of thread. The spool allows dual directional flow of fluid by reversing the high pressure and low pressure settings.
Engaging the Valve
When a piece of hydraulic equipment is in use, an operating lever will be positioned so as to connect high pressure to the bottom of a cylinder. At the same time, the spool positions the top of the cylinder to a return line to force out hydraulic fluid.
Disengaging the Valve
After the required function has been performed, the operating lever will be positioned in the opposite direction. This will force hydraulic fluid onto the top of the cylinder and force it downwards, moving the fluid at the bottom of the cylinder back to its source tank.
Resetting the Valve
Upon completing the required action, a control lever will reposition the valve into a neutral or center position.