SystemStak™ Pilot Operated Relief Valves
These two-stage valves limit system pressure by directing flow to tank or the opposite cylinder port (A-B/B-A crossport types) when system pressure reaches the valve setting. Pressure control may be obtained in “A”, “B”, “A” and “B”, or “P” port, and pilot flow may be internally or externally drained, depending on model type. Any pressure in the line to which these valves are drained is additive to the valve pressure setting.
The valve pressure setting is adjustable by means of either an adjusting screw and locknut, a hand-knob adjuster, or a micrometer knob with keylock. External remote control/vent connections are available on all models except crossport relief.
SystemStak™ Counterbalance Valves
Eaton SystemStak counterbalance valves provide continuous protection from pump cavitation and prevent an actuator from running ahead of the pump supply. These valves also provide thermal relief protection in closed systems.
NOTE Counterbalance valves adjust in the opposite direction of other pressure control valves. Turning the adjuster counterclockwise increases the valve setting. Turning the adjustment clockwise lowers the pressure setting, releasing the load.
Drain Any pressure in the line to which these valves are drained is additive to the valve pressure setting
SystemStak™ Internal Pilot Operated Sequence Valves
These two-stage pressure operated valves are normally closed to flow through the main spool flow path. When system pressure reaches or exceeds the valve setting, the main spool flow path opens. Pilot flow may be externally or internally drained to tank.
Any pressure in the line to which these valves are drained is additive to the valve pressure setting. The valve pressure setting is adjustable by means of either an adjustable screw containing an internal hex, a hand-adjust knob, or a micrometer knob with keylock. Different spring ratings cover an overall pressure range from 5 to 315 bar (75-4500 psi).
SystemStak™ Pressure Reducing Valve Modules
These two-stage adjustable pressure reducing modules are used to regulate the downstream pressure in the line in which the integral reducing valve is installed, whilst the upstream pressure fluctuates above the reduced pressure.
The valve elements are formed as cartridges for ease of construction and servicing.