Use an all-ports-open directional valve with the pilot-operated check valve. This accumulator circuit maintains pressure in the cylinder while unloading the pump.
How do accumulators work?
The dump valve (which is a high-ratio, pilot-to-close check valve) is held closed by pump idle pressure until the pump shuts down. To maintain pressure: Another common application for accumulators is to maintain pressure in a circuit while the pump is unloaded. This is especially useful when using fixed-volume pumps on long holding cycles.
What is a pilot valve?
A pilot valve can be used to remotely control the directional control valves, cylinders, pumps, or motors. A pilot valve can be considered as a pressure reducing valve. Some pilot valves can be used with a remote pilot source. So by this feature, a valve can be shifted from a remote pressure source by other valves in the logic circuit.
What is a pilot actuated valve?
Pilot valves are valves that can control high flows in a system. Mostly the pilot actuated valves are shifted by the pressurized fluids. When the set pressure is reached then the valve would open and release the pressure. When the pressurized fluid hits the valve piston then the flow directing element of the valve would change.
This circuit uses a pressure-compensated pump that maintains pressure with minimal heating during normal operation. An accumulator F stores the first pump flow, check valve D stops accumulator back flow, and normally open directional valves C isolate the accumulator from the cylinder and tank during normal operation.
How do accumulator pumps work?
Now, stored energy in the accumulator is ported to tank through the orifice. This circuit is very reliable because it depends on system or pump pressure to close and/or open valves. A fixed-volume pump must be ported to tank at very low pressure when its flow is not doing work.
What is pilot controlled DCV?
Because the system would require a huge force to shift the spool, pilot controlled DCV is employed to regulate the system with high flows. As a result, the pilot valves are mounted on top of the main valve. As a result, the pilot valve would move the main valve hydraulically. The valve piston is operated indirectly in this valve.