Accumulators are often used in hydraulic systems, but many people don’t fully understand how they work. This article explains what hydraulic accumulators do and how they make systems more stable. This article will also help you decide whether an accumulator is right for your hydraulic system.
Why Hydraulic Systems Use Accumulators？
When a hydraulic system is in use, the pressure can go up and down when the actuator starts or stops moving. If you need a lot of hydraulic fluid, the pump might not be able to supply it immediately. If the load changes a lot, the pump also changes how it works. This puts more strain on the system and its parts. These situations are not due to a single faulty part; they are the result of the difficulty in maintaining system stability during operation. Hydraulic accumulators help the system to work more smoothly when there are changes in pressure. This makes the overall working process more stable.
How a Hydraulic Accumulator Works？
The way a hydraulic accumulator works is based on changes in system pressure. When the pressure in the system increases, the extra energy is temporarily stored in the accumulator. When the system pressure decreases, or when a certain action suddenly needs more fluid, this stored energy is returned to the system to be used. The accumulator doesn’t supply energy to the system all the time. It only gives support when the system needs it. Its job is to help the system deal with these changes, not to take the place of the hydraulic pump in the long term.
Main Functions of a Hydraulic Accumulator in a System
Supplying Extra Flow During Peak Demand
In a hydraulic system, when equipment suddenly starts moving or several actions happen at once, the system needs more hydraulic fluid. At this point, the hydraulic pump might not be able to supply enough fluid immediately. The accumulator releases the energy it has stored. This supplies the necessary fluid and helps the equipment work more smoothly.
Reducing Pressure Fluctuation and Hydraulic Shock
When a hydraulic system starts, stops, changes direction, or experiences load variations, the pressure in the pipelines can suddenly increase or decrease. This is often followed by loud noises and big shocks. An accumulator is a device that absorbs excess energy when the pressure suddenly rises and releases that energy when the pressure drops. This makes the system run more smoothly and reduces the impact on the equipment.
Protecting Pumps and Hydraulic Components
If the load changes a lot, hydraulic pumps and valves are put under more pressure, and pipelines are more likely to be damaged. An accumulator can absorb some of this pressure during these changes, so that the hydraulic pump doesn’t have to deal with the full load all the time. This reduces the impact on the valves and pipelines. This reduces wear and tear on the parts, making the whole hydraulic system more stable and durable.
Providing Temporary Hydraulic Support in Emergencies
When the hydraulic pump stops working or the equipment suddenly loses power, the system sometimes still needs to do some basic actions, such as putting components back in place. In this situation, the energy that was stored in the accumulator can be used to provide the necessary pressure to the system, helping to complete these actions.
When Is a Hydraulic Accumulator Especially Useful?
When you’re deciding whether you need a hydraulic accumulator, it’s more important to think about how the equipment works during its working cycle than to focus on choosing a specific component. The following system conditions usually need an accumulator:
The System Does Not Work All The Time
If the actuating elements only work sometimes, or the load often changes, the system will always need more fluid and pressure.
Systems with Fast Equipment Motion Switching
When the equipment starts, stops, or changes direction quickly, the system needs to keep up with these changes rapidly. Otherwise, the motion may be jerky or irregular.
Systems That Need Stable Pressure
Some equipment needs to be used in a certain way so that the pressure doesn’t change a lot while it’s switched on. If it does, it might not work as well as it should.
When an Accumulator May Not Be Necessary？
Not all hydraulic systems need an accumulator; it depends on how the system is actually used. In systems where the load stays about the same for a long time, the hydraulic pump usually works fine. In these conditions, the system can still work normally even without an accumulator. So, the decision to include an accumulator should be based on the system characteristics, but not on a fixed configuration.
Common Misunderstandings About Hydraulic Accumulator Function
Accumulators Are Not a Universal Fix
In actual use, hydraulic accumulators are sometimes used to solve various system problems. But it’s important to remember that accumulators can’t fix all problems. If the system has problems in circuit configuration, component matching, or control methods, adding an accumulator will usually not improve the system’s performance.
Accumulators Cannot Compensate for Poor System Design
In some systems, accumulators are used to reduce the effects of a hydraulic pump that is not strong enough or a circuit that is not designed well. In these cases, the accumulator only has a supporting role and cannot fix basic design problems in the system itself. It’s important to understand this so you don’t expect too much from the accumulator.
FAQ
Where are hydraulic accumulators usually put in a system?
Hydraulic accumulators are usually installed near the hydraulic pump outlet or close to the circuit location where stable pressure and flow are required. This makes them respond more directly to system changes.
Does the accumulator keep its pressure after the system is switched off?
Yes, after the system is switched off, the accumulator usually keeps a bit of pressure in it until it is released through the circuit or a specific pressure relief operation is done.
Do accumulators need to be checked or maintained while they are being used for a long time?
Accumulators should be checked regularly to make sure they are working properly and are safe. This includes checking the pressure and sealing condition when used over a long time.
What problems can arise if the accumulator is not set up properly?
If you don’t set it up properly, you might get unstable pressure, unusual system behaviour, and the hydraulic pump and valves might be put under more strain.
Do accumulators, hydraulic pumps, and relief valves affect each other?
Yes, how the accumulator is working will affect how the pump works and the relief valve opening. So, it’s important to consider how they interact with the system when you’re designing it.
Final Thoughts
Hydraulic accumulators are designed to help hydraulic systems deal with changes in pressure and oil flow. They help the system to work more smoothly during changes in movement and when the load changes. Target Hydraulics has been manufacturing hydraulic components for over ten years. We can give you advice on selecting the right parts, how to use them, and provide complete solutions related to accumulators. If you have any other needs while designing or improving your hydraulic system, please contact us.
