Hydraulic systems provide powerful, reliable, and controllable power transmission solutions for many industrial and mobile applications today. To ensure that these systems operate more efficiently, stably, and safely, various auxiliary components are used. One of the most important of these components is the accumulator. So, what is an accumulator, what does it do, and what types are available?
WHAT IS AN ACCUMULATOR?
An accumulator is a pressurized vessel used in hydraulic systems to store energy in the form of fluid pressure and release it back into the system when needed. It typically consists of two chambers—one filled with gas (usually nitrogen) and the other with hydraulic fluid. Since gas is compressible, when excess oil enters the accumulator, it compresses the gas, storing energy. This stored energy is then released when system pressure drops or fluid is needed.
The fundamental working principle of an accumulator lies in the pressure differential between the hydraulic fluid and the gas. The gas side is pre-charged with a specific pressure. As the system operates, fluid from the pump enters the accumulator, compressing the gas. This compression stores energy. When the system requires a sudden motion or experiences a pressure drop, the gas expands and pushes the fluid back into the system.
Accumulators are not just energy reservoirs; they also contribute to quieter, more balanced, and longer-lasting system operation. They support the system during sudden load changes that the pump cannot immediately compensate for, improving performance and reducing wear on components.
WHAT ARE THE FUNCTIONS OF ACCUMULATORS?
Accumulators can simultaneously fulfill several critical functions in hydraulic systems:
- Energy Storage: They supply the required energy when the system is idle or when the pump is insufficient.
- Pressure Stabilization: By absorbing pressure spikes, they help maintain system balance.
- Shock Absorption: They dampen shocks and vibrations caused by sudden loads, protecting valves, pumps, and other components.
- Backup Power Source: In cases such as power outages, they provide temporary system operation, ensuring continuity.
- Leakage Compensation: They maintain system pressure by compensating for minor fluid leaks over time.
COMMON TYPES OF ACCUMULATORS
Accumulators are manufactured in different structural forms. The most commonly used types include:
- Bladder Type: Contains a rubber bladder filled with gas, surrounded by hydraulic fluid. It is ideal for systems with rapid response requirements due to its fast reaction time.
- Piston Type: Uses a movable piston to separate the gas and fluid. It is suitable for high-pressure and large-volume applications.
- Diaphragm Type: Gas and fluid are separated by a flexible diaphragm. Its compact design makes it ideal for low-volume systems.
- Weight-Loaded Type: Less commonly used, typically found in stationary systems. Operates with a weight placed on top to create pressure.
IN CONCLUSION
Accumulators play a crucial role in ensuring both the efficiency and safety of hydraulic systems. With functions such as energy storage, pressure balancing, and shock absorption, they enhance system performance and extend equipment lifespan. A properly selected and well-integrated accumulator reduces maintenance costs and minimizes failure risks. It is essential not to overlook these auxiliary yet impactful components when designing hydraulic systems.
In this week’s article, we discussed the purpose and types of accumulators used in hydraulic systems. See you in our next post!