Energy for Hydraulic Applications

Accumulators from Freudenberg Sealing Technologies

With the acquisition of Tobul Accumulator Incorporated, Freudenberg Sealing Technologies (FST) now offers its customers a complete line of hydraulic accumulators which include piston, diaphragm and bladder. Whether your application is stationary or mobile, Freudenberg combines market knowledge, the latest in technology and global support for your next application. We achieve customer-specific solutions of less than one liter of storage volume, including special weight and space-saving, low-volume piston accumulators. Freudenberg Sealing Technologies is already a global market leader in automotive applications with its multifaceted piston and diaphragm accumulators and now we strive to be a leader in all markets.

General Industry Market

At the push of a button, our hydraulic accumulators get roller coasters moving and offer exceptional functional reliability. With a turn of a key, our accumulators decrease operational costs by assisting construction equipment with storing and reusing energy along with weight reduction. Freudenberg Sealing Technologies creates solutions for a wide spectrum of applications like steel presses, agriculture and wind turbines without compromising quality.

Oil and Gas Market


Accumulators manufactured by Freudenberg Sealing Technologies – Tobul Accumulator Incorporated enhance the safety of operations in this industry by incorporating the latest in technology in meeting or exceeding industry safety regulations. As an energy storage device, accumulators provide instantaneous hydraulic power for emergency safety functions, such as blowout preventers used on drilling rigs, and valve actuators in well control mechanisms. Accumulators also increase the efficiency of hydraulic systems and help to eliminate detrimental pulsations.

What are Accumulators and How Do They Work

A hydraulic accumulator (or hydro-pneumatic accumulator) is a pressure vessel that performs many tasks in a hydraulic system. They are used to maintain pressure, store and recapture energy, reduce pressure peaks, power chassis suspensions, and dampen shock, vibration and pulsations.
Under gas pressure, accumulators store a volume of fluid that can be re-fed into the hydraulic system when it is needed. Depending on the type of accumulator, a diaphragm, a piston or an elastomer bladder separates the hydraulic fluid from gas within a pressure shell. With a rise in pressure within the hydraulic system, the hydraulic accumulator collects the pressure fluid. The result: The gas is compressed. If the pressure falls, the compressed gas expands again and forces the stored fluid into the hydraulic circuit.

Both the elastomer and the sealing system play a crucial role in the performance of hydraulic accumulators. Freudenberg’s hydraulic accumulators achieve the maximum possible performance and service life due to the application specific elastomer compounds we develop as well as state-of-the-art diaphragms and sealing systems.

The Advantages

  • Complete product line from a single source for diverse applications
  • Long service life, less maintenance and outstanding performance with Freudenberg sealing solutions such as seals, diaphragms/membranes from FST provide advantages over the competition – all from one source, the leading global sealing and accumulator expert.
  • Reliability in broad temperature ranges and under high pressures up to 2750 bar (40,000psi).
  • Extreme burst strength and high allowable dynamic loads on the accumulator vessel due to application-specific materials
  • A variety of hydraulic and gas port connections for customer-specific solutions
  • A variety of global third party quality certifications available on request

Our Products in Detail

Hydraulic Accumulators

Freudenberg Sealing Technologies hydraulic accumulators can be “tailored” to meet customers’ design specifications which include size, fluid volume, pressure, corrosion resistance, materials and certification requirements. Based on decades of experience Freudenberg offers innovative solutions in materials, design and functionality in hydraulic accumulators.

Piston Accumulators

Our piston accumulators are multifaceted “all-around players”: In more than 90 percent of all potential applications, they offer a solution that works. Hydro-pneumatic piston accumulators meet extremely varied requirements in a range of different industrial sectors – with volumes ranging from a few cubic centimeters to over seven hundred liters and with pressure stages as high as 2750 bar (40,000psi). Their performance capacity and long lifespans are based on their extremely high quality. Other pluses are the comprehensive selection of oil and gas connections available for them as well as a broad portfolio of potential materials, types of seals and configurations.

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Diaphragm Accumulators

Our diaphragm accumulators are available with various configurations, materials, and oil and gas connections. They are designed for extremely demanding applications, which often require extraordinary load-carrying capacity and a low weight. Outstanding functional reliability and longevity in a wide range of different applications are typical of Freudenberg Sealing Technologies diaphragm accumulators: at operating pressures of up to 350 bar (5,000psi) and with extreme temperature requirements.

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Bladder Accumulators

With extreme durability and seamless housings, our bladder accumulators allow fast responses to the requirements of fluid systems while simultaneously standing up to extreme pressures. They are used in a wide variety of applications, cover wide temperature ranges, and provide long operation time. Freudenberg Sealing Technologies bladder accumulators are distinguished by their outstanding damping action and are available in a variety of standard volumes and pressure stages.

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