DEFINITION: Accumulator is a simple hydraulic device which stores energy in the form of fluid pressure for future use.
Dry nitrogen is used to pre-charge accumulators for several reasons:
 It is an inert gas. This means it will not react to external conditions such as heat and compression or pressurization. It also does not react readily with other chemicals.
 Although any inert gas could be used, nitrogen is the cheapest because it is the most readily available of the earth atmosphere with 78% in the air.
Note: Oxygen or compressed air cannot be used to charge an accumulator! As the oxygen is compressed it heat up and can cause a fire or explosion when mixed with the hydraulic oil.
Here are the few functions of accumulator
EMERGENCY AND SAFETY: An accumulator which is kept constantly under pressure is valuable in the event of an electrical power failure as it can provide flow and pressure to perform an additional function or complete a machine cycle.
SHOCK OR PULSATION DAMPENING: An accumulator can be used to cushion the pressure spike from sudden valve closure, the pulsation from pumps or the load reaction from sudden movement of parts connected to hydraulic cylinders.
LEAKAGE COMPENSATION: An accumulator can be used to maintain pressure and make-up for lost fluid due to internal leakage of system components including cylinders and valves.
THERMAL EXPANSION: An accumulator can absorb the pressure differences caused by temperature variations in a closed hydraulic system.
ENERGY CONSERVATION: The accumulator is charged during low demand portions of the pump cycle time and then discharges during the high demand portions of the system.
NOISE REDUCTION: An accumulator is effective at reducing hydraulic system noise caused by relief valves, pump pulsations, system shock and other circuit generated noises.
IMPROVED RESPONSE TIMES: An accumulator (bladder type) has virtually instantaneous response time that can provide fluid very quickly to fast-acting valves such as servos and proportional to improve their effectiveness
Conclusively an accumulator can increase efficiency, provide smoother, more reliable operation, and store emergency power in case of electrical failure.
Accumulators are recharged in Kezif Integrated Resources Ltd under a safe and well controlled environment. High purity nitrogen is used in the recharge of Accumulators up to the specified/required pressure.

The recharge is done by well trained and qualified personnel and on time.
If needs arises, you can visit us at no. 100 trans woji road Port-Harcourt.

See More: The importance of charging an accumulator for future use