Hydraulic Accumulators
What is a diaphragm accumulator and for which hydraulic application do you need one?
Diaphragm accumulators have a rubber plate or diaphragm as the separating element. This element is either welded or screwed together between two spherical shells (or compartments). The compartment above the diaphragm is filled with nitrogen. The compartment below is directly connected to the hydraulic circuit. Diaphragm accumulators are the smaller of all hydraulic accumulator types and available at fluid storage capacities of 0.075 to 4 litres.
Diaphragm accumulators have low fluid storage capacity but can handle high gas compression ratios.
Thus diaphragm accumulators are useful if the required fluid storage capacity is low (i.e. 4 litres or less). Diaphragm accumulators have most of the advantages of bladder-type units, but can handle gas compression ratios of up to 8:1. However, they are limited to smaller volumes, and their performance can sometimes be affected by gas permeating across the diaphragm. The small size and numerous mounting options makes it very useful for mobile applications.
Types Of Diaphragm Accumulator:
- Welded type diaphragm accumulator
- Threaded type diaphragm accumulator

What is a piston accumulator and for which hydraulic application do you need one?
Piston accumulators use pistons as separating elements. They can handle much higher gas compression ratios (up to 10:1) and flow rates as high as 215 litres (57 gallons) per second. Therefore the maximum pressure of the hydraulic fluid stored in a piston accumulator and the velocity with which the hydraulic fluid is released to the hydraulic system can be much higher. However, the piston inside the accumulator causes internal friction that negatively affects reaction speed.
Piston accumulators store large amounts of fluid and benefit from high compression ratios and flow rates.
Compared with hydraulic accumulators that use a different separating element (i.e. bladder or diaphragm), piston accumulators require a higher level of fluid cleanliness. Piston accumulators are used in applications that demand very large fluid storage requirements of up to 2,500 litres in a single hydraulic accumulator at very high pressures (up to 1,000 bar). The flow rate of piston accumulators is second to none so even at smaller fluid storage requirements and lower pressures, you may find the piston accumulator the best available type of hydraulic accumulator.
Types Of Piston Accumulator:
- Piston accumulator spare parts
- Piston accumulator with position control
- High pressure piston accumulator

What are accumulator accessories and for which hydraulic applications do you need such parts?
Accumulators are pressure vessels and therefore must be handled with care. To mount the accumulator safely, special fixing elements are available. Moreover, an accumulator should never be installed without a safety and shut-off control block. Special testing devices are available to test pressure of the nitrogen gas. Testing should be carried out at least once a year. Mobile nitrogen charging devices are available to replenish the gas or change the prefilled pressure.
Hydraulic accumulators are pressure vessels and must be handled with great care to ensure safe usage.
You can contact DTA for all your accumulator accessory needs. We supply hydraulic accumulator mounting kits and fixing elements, charging and testing devices with adapters to all commonly used gas valves, fluid port connectors and adapters, safety and shut-off blocks and spare parts thereof, nitrogen bottles in various sizes and precharge pressures, and more. To ensure safe usage of hydraulic accumulators, use the manufacturer’s specification accessories only.
Types Of Accumulators Accessories:
- Charging and testing unit
- Gas pressure vessels
- Safety and shut-off blocks
- Accumulator mounting elements
