These are pressure accumulators in which the compressibility of nitrogen gas is used. They are used for capacity correction and pulsation absorption in hydraulic circuits.
Accumulators are necessary to make the potential energy of the fluids operate efficiently, and are also necessary for the safe and economical operation of oil, water, or other circuits to work safely and to maintain their high level of accuracy. The principle of operation is based on the compressibility of nitrogen. After fluid pressure has been stored in an accumulator, a large amount of pressurized fluid is instantaneously released. Pulsation or impact pressure is also absorbed.
According to the method of isolation, accumulators are classified into two types: the bladder type and the piston type. These days, bladder type accumulators are more commonly used.
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