Hydraulic Valves Flashcards
Why do we need Hydraulic Valves?
To control pressure, direction, flow.
Do pumps generate fluid flow or pressure?
Fluid Flow, regardless of type of pump! Pressure is the result of resistance to flow.
What is the function of a pressure control valve?
Limits maximum pressure or regulates reduced pressure in certain portions of a circuit
Types of pressure control valves (6 introduced)
Pressure relief valves, sequence valves, pressure reducing valves, unloading valves, counterbalance valves, and brake valves.
Pressure Relief Valve
Found in virtually every hydraulic system. It is normally closed. It is responsible for limiting maximum pressure in system. It diverts all or part pump output back to the reservoir.
What does normally closed mean?
Pressure port is blocked in an un-actuated position. Normally closed when the system is not running. It is open when the system pressure is over the pressure setting. Back to closed when the system pressure drops below the setting.
