Accumulator: It is a device which stores the pump delivery when it is not required by the system and makes available to the system whenever required.

Necessity of accumulator for every huge hydraulic press:

Oil requirement of the system is not continuous but intermittent. A hydraulic press needs the oil only during the lifting operation. While, during the lowering of load, holding the load or during idle period, it doesn’t not require any supply of oil. During such period, the hydraulic pump has to stop or delivered oil must be drained back to the sump. But frequent starting and stopping of pump is not desirable as it reduces the pump life. Also, draining the pressurized oil is wastage of power which reduces the system efficiency.

The remedy to above problem is to use accumulator in the system.