PLUNGER A. 8B3318 - Caterpillar

Illustration 1 g01150501
Pilot Manifold (1) Pilot accumulator
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(A) Bladder (B) Steel chamber (C) Gas chamberThe accumulator has two functions:
Store energy.
Release the energy to the system.Pilot accumulator (1) provides oil for the following functions:
Release of the swing brake
Lowering the boom and the stick in the event of loss of pilot system pressure
Lowering the boom and the stick after stopping the enginePilot accumulator (1) stores pressurized hydraulic oil by taking advantage of the compressibility of nitrogen gas in the gas chamber. The valve disc seals the oil inlet when the diaphragm is fully extended.The pilot pump oil goes through the inlet port and into the oil chamber. Entering oil acts against the gas that is in the chamber through the bladder in order to maintain oil pressure. The factory filled nitrogen charged accumulators must be replaced if the accumulators fail.