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Accumulators Tailored for Military Aircraft and Rotorcraft

By August 8, 2023 January 17th, 2024 No Comments

Positive displacement hydraulic accumulators serve as self-contained sources of hydraulic pressure. The gas-charged piston-based accumulators allow hydraulic systems to quickly respond to changes in pressure demand and can also smooth out pulsation from pumps and other cycling devices up and downstream. Using accumulators often allows for the use of smaller pumps, providing for a lower system weight and footprint. Valcor’s innovative design features a hydraulic reservoir made with a proprietary composite fiber wrapping over a thin metal sleeve. This provides for pressure ratings to 4000 PSIG, while saving up to 40% of the weight found in competitive products. Dual piston seals provide for positive separation of the charging gas from the process media. Valcor’s accumulators can be delivered with integrated valves, gauges, and other items, making this a compact unit with lots of features, simplifying the customer’s overall system.

Integrated accumulator and components save critical space and weight.

Positive displacement hydraulic accumulators are used in aircraft and rotorcraft applications, including emergency backup hydraulic power for landing gear and braking systems. They also provide the pressure required to drive the motor of auxiliary power units.

The majority of Valcor accumulators are piston type accumulators with the high pressure hydraulic fluid separated from the charge gas by a piston. We offer a wide range of sizes and fluid volumes. Our stable of accumulators include self-displacing and non-self-displacing designs. The self-displacing accumulator consists of high-pressure hydraulic fluid and dry nitrogen chambers separated by a piston, and a low-pressure hydraulic fluid chamber (reservoir) containing a second piston connected to the first piston. Valcor’s accumulator product line already designed and qualified can be found on our website at

Valcor also developed a highly customized accumulator that uses a bellow to separate the charge gas for the hydraulic fluid. This eliminates the need to periodically replace piston seals. The accumulator is “maintenance free” as it is installed in a location of the aircraft that is inaccessible by technicians. This robust design was successfully tested to 500,000 cycles and has been in continuous production and use for over 20 years.

Maintenance-free accumulators are a boon that enhance system architecture and minimize logistics requirements.

Valcor has also developed hydraulic subsystems including accumulators, valves, and sensors.

Key features of Valcor accumulators are:

  • Up to 40% lower weight than competitive products
  • Composite fiber wrapping over metal sleeve for high strength and low weight
  • Dual piston seals for positive gas/liquid separation
  • Self-displacing to achieve max pressure differential
  • Self-lubricating seals for exceptional cycle life
  • Maintenance free bellows construction
  • Integrated control valve module
  • Optional accessories include thermometer, pressure gauge, piston position indicator, and pressure switches
  • Fully customizable for your application
  • Passed military ballistics requirement

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