Devices that store energy called hydraulic accumulators


Hydraulic accumulators have the ability to store excess energy and release it when needed. They are useful tools for improving hydraulic efficiency.

Industrial accumulators are classified as hydro pneumatic. This type of accumulator applies a force to a fluid by the use of compressed gas.

The two most common types of accumulators are the rubber bladder type and the piston accumulator.

Below will be presented the accumulators rubber bladder type.

The rubber bladder is compressed when the fluid under pressure is supplied to the hydraulic accumulators and the gas and oil pressure increases. Conversely, when accumulator supplies oil to the hydraulic system, the oil pressure drops and the rubber bladder expands.

Whenever additional oil is required by the system, it is supplied by the accumulator even as the pressure in the system drops by a corresponding amount.

The bladder is pre-charged with nitrogen to a pressure specified by the manufacturer according to the operating conditions.When the system pressure exceeds the gas pre-charged pressure, the oil valve opens and hydraulic fluid enters the accumulator.

Rubber bladder types consist of the following:

1.Steel pressure oil container

2.Rubber bladder separating the fluid and gas

3.Oil valve that prevents the bladder from being pressed out of the accumulator when the hydraulic pressure is lower than the charging pressure of the bladder.

4.When charging the bladder to the desired pressure required a gas valve

5.Valve cap


 accumulator


A common failure of accumulators is bladder punctures because faulty installation or neglected maintenance of the accumulator.

Accumulators can be used during power failure or when additional energy is needed. In certain situations additional flow may be needed. An accumulator can be used to supplement the flow rate of a pump.

Accumulator circuits should be equipped with a safety unloading valve. This valve allows the accumulators to be isolated and discharged to the tank prior to system maintenance.


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