
Metal bellows accumulators
Hermetic separation for the strictest requirements
HYDAC metal bellows accumulators represent the high-end solution in hydraulic accumulator technology. Unlike conventional accumulators, these devices use metallic bellows as a separation element between the nitrogen and the hydraulic fluid. This design guarantees absolute gas leaktightness and makes the accumulator maintenance-free throughout its entire service life. They are the first choice when elastomers (diaphragms or bladders) reach their physical limits due to extreme temperatures or chemically aggressive media.
Performance profile and materials
| Feature | Technical advantage | Target application |
| Hermetic tightness | No gas loss over years, maintenance-free | Aviation, applications with high-cleanliness media, compression of precious gases and hydrogen, inaccessible systems |
| Temperature resistance | Application range from -65 to over 160 °C | Low-temperature technology, very high ambient temperatures |
| Chemical resistance | Stainless steel bellows for aggressive media | Chemical industry, medical technology, high-safety applications |
Reliability in critical environments
Metal bellows accumulators eliminate the risk of sudden diaphragm breakage or the stick-slip effect in piston accumulators. Since metal bellows are manufactured from stainless steel, unlike conventional separation elements, they are highly media-resistant and have a significantly higher resistance to deterioration. Thanks to their metallic properties, they are also not sensitive to extreme temperature ranges, making them the ideal solution for reliable long-term use in safety-critical applications. The precise production of the bellows geometry ensures defined response characteristics and enables precise pulse damping even for the smallest pressure differences.
Investment security thanks to total cost of ownership
Although metal bellows accumulator have higher initial costs than standard solutions, they pay off by eliminating regular testing and charging intervals and by reducing downtime. HYDAC supplies metal bellows accumulators with comprehensive certifications for highly regulated markets. The compact design allows them to be integrated directly into existing housing structures, making them a technically superior solution for OEM manufacturers who need to guarantee maximum reliability.