Hydraulic accumulatorthat uses a gas as the medium for applying a load to the hydraulic fluid (air foraccumulators for water hydraulics, nitrogen for oil accumulators).
As a consequence of the gas cushion the accumulator pressure drops with increasing withdrawal of the usable volume in accordance with the ratio of gas capacity to oil volume (Figure G 1).
Alternative: spring accumulator, weight accumulator.
Figure G 1: p/V diagram of a hydraulic accumulator