|
Valves
- Open-center, open-center-power-beyond and closed-center are terms used to describe
hydraulic valves in the neutral position.
- Open-Center - used with a fixed-displacement pump, allows oil to free-flow back to the tank in neutral position. Shifting the spool redirects oil to the selected work port.
- Open-Center-Power-Beyond - Same as Open-Center valve except oil flows to downstream circuit in the neutral position instead of returning to the tank.
- Closed-Center = Typically used with a variable-displacement pump, oil flow is blocked at the valve until the spool is shifted from neutral.
- Motor-spool - In the neutral position fluid is allowed to flow back to the tank. This allows the operator to run a hydraulic motor under load and, when the valve is shifted to stop flow to the motor, allows the motor to coast to a stop.
- Cylinder-spool - In the neutral position fluid is blocked from flowing to the tank. This effectively locks the load in place and should be used in applications where a load is to be raised and held aloft with a hydraulic cylinder.
- Three-way valve - Typically used to control single-acting circuits.
- Four-way valve - Typically used to control double-acting circuits.
|