Unload accumulator in a hydraulic system


Unload accumulator in a hydraulic system

Accumulator is used for many purposes and being subject to the safety legislation of pressure vessels I will present a simple bleed down accumulator circuit.

Accumulators are one of the dangerous components of a hydraulic system. With a large pressurized fluid stored which released in an uncontrolled manner, can cause serious injury.

Maintenance is the first step to eliminate malfunction and breakdowns in the hydraulic system. Accumulators are devices which can collect pressurized liquid and released when needed it.

In any hydraulic system is very important to know to unload the accumulator when system is shut down or losses power and the stored fluid is not needed for emergencies operation.

Discharge accumulator in a hydraulic system

A good method is to be fitted in the system an electromagnetically operated pressure relief valve to accumulator pressure line. Either a normal open 2/2 valve or 4/2 valve normal open with port P and A plugged is in use with power supplied by the starting of the electric motor. When electric motor is shut down for any reason the accumulator will be automatically discharge, unload.

4/2 valve normal open with port P and A plugged                  2/2 valve normal open                                          

When electric motor the starting point of any hydraulic system is switch on the solenoid is energized the valve switch to a non-passing state allowing the accumulator to be charge. 

When the motor is switch off the solenoid de-energizes and the valve opens and the accumulator discharge to tank.

Here the are shown in the diagram form.

Accumulator – bleed down diagram

Always think about your safety and then of others. Think carefully before any commencing work in a hydraulic system.

Know how to drain an accumulator safely is of paramount importance.

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