In a hydraulic system energy can transfer by means of pressure. Sometimes though it is also necessary to store the hydraulic energy for a short time. Thus we use hydraulic accumulator. As we store energy by compressing spring or inflating balloon similarly we can store energy in accumulator in same manner. We use pressure for storing energy in both spring and balloon. Below in some paragraph you can find hydraulic accumulator working principle.
A hydraulic accumulator is used to store the hydraulic energy by using back pressure of gas, spring or weight. Hence we can categorise the accumulator in following.
- Gas pre-charged accumulator
- Spring loaded accumulator.
- weight load accumulator.
1. Gas pre-charged hydraulic accumulator working principle
A gas pre-charged accumulator is charged with a non-toxic, non-reactive gas such as nitrogen. When system’s hydraulic pressure increases above the accumulator charging pressure the gas begins to compress. Hydraulic oil starts to flow in accumulator container. The gas and oil separates by mean of some membrane. That happens until the gas pressure matches the hydraulic pressure. Hydraulic kinetic energy is now store in potential energy in gas pressure. When the pressure in the hydraulic circuit declines, the same thing happens in the hydraulic accumulator. The gas expands again. The stored energy now converts back into motion. It pushes the hydraulic fluid back into the circuit until the gas pressure has dropped to the value of the hydraulic pressure or original pre-charge pressure whichever is more. In fact charging discharging accumulator is very fast and happens at the same time with system pressure.
In the 2nd page we will see how accumulator can help us in hydraulic system in more details.