Precision Metal Bellows Accumulators (Low-Pressure & Extreme Media)
Unlike conventional polymer and elastomeric accumulators, Schwerll metal bellows accumulators incorporate a multi-convolution welded or hydroformed stainless steel bellows element. This all-metal internal barrier ensures 100% hermetic gas-to-fluid separation, completely eliminating the gas permeation, rubber degradation, and media contamination typical of polymer seals.
Key Engineering Specifications
- Design Working Pressure: Low-pressure to medium-pressure configurations from 10 bar up to 50 bar (Custom engineered up to 100 bar)
- Nominal Capacity: 0.1 L to 50 L
- Bellows Materials: Austenitic Stainless Steel (AISI 316L, 321), Inconel 718, or AM350 for exceptional fatigue resistance
- Extreme Temperature Envelope: Cryogenic -196°C up to high-temperature +200°C (+350°C available for specialized aerospace fluids)
- Gas Tightness: Helium leak rate less than 1×10⁻⁸ mbar·L/s (virtually zero gas charge loss over 10+ years service life)
Distinct Engineering Advantages
- Zero Elastomer Aging: Completely free of rubber bladders, O-rings, or dynamic elastomeric seals in the primary gas boundary, eliminating scheduled bladder replacement maintenance.
- Zero Fluid Permeation: Eliminates gas migration into hydraulic oil and fluid contamination across aerospace fuels, ultra-pure water, and corrosive chemicals.
- Extended Fatigue Life: Finite element analysis (FEA) optimized convolution geometry ensures over 1,000,000 full compression-expansion cycles without metal fatigue.
- Maintenance-Free Operation: Ideal for remote, sealed, or inaccessible installations such as subsea valves, aerospace flight control actuators, and nuclear valve dampening.
Primary Applications
- Aerospace & aviation auxiliary power unit (APU) and landing gear emergency extension
- Subsea actuator hydraulic volume and thermal expansion compensation
- Semiconductor and high-purity chemical fluid pulsation dampening
- Heavy-duty industrial thermal expansion compensation in sealed oil loops
