Product Overview
The Short Stroke Precision Edge Welded Bellows is engineered for applications where space is constrained but precision cannot be compromised. With a compact form factor and high-stiffness convolution geometry, this bellows delivers ±2–4mm of precise, repeatable axial motion ideal for vibration isolation mounts, thermal expansion compensators, and precision actuator seals in scientific instruments, optical systems, and semiconductor metrology equipment.
Unlike long-stroke bellows optimized for maximum travel, this design prioritizes high natural frequency, low hysteresis, and excellent vibration damping. The reduced convolution depth and optimized wall thickness produce a stiffer spring rate that resists unintended displacement — critical for maintaining optical alignment and sensor calibration in vibration-sensitive environments. For dimensional options, see the short-stroke range in our AT-Series Catalog.
Key Benefits
- Ultra-compact design minimizes installed length — ideal for tight instrument envelopes where every millimeter of space is budgeted
- High rigidity, high natural frequency — resists unintended displacement from ambient vibration, protecting optical alignment and sensor calibration in metrology and laser systems
- Superior vibration isolation — the all-metal edge welded structure provides effective damping without the creep and aging issues of elastomeric isolators
- Low hysteresis — near-linear force-displacement curve with minimal energy loss per cycle, enabling precise open-loop positioning without sensor feedback
- Extended life at high frequency — 1 million+ cycles even at elevated cycling rates; the short stroke reduces per-cycle stress amplitude, extending fatigue life
Technical Specifications
- Material: SS316L Stainless Steel — AM350 available for maximum high-frequency fatigue resistance (see Material Selection Guide)
- Vacuum Level: 10⁻⁸ mbar (standard); UHV 10⁻¹⁰ mbar with copper gasket sealing
- Operating Temperature: -196°C to +350°C (SS316L); Inconel 718 option to 700°C
- Axial Stroke: ±2–4mm (compression-dominant design)
- Spring Rate: High stiffness — typically 50–500+ N/mm range (application-specific; consult engineering)
- Cycle Life: 1,000,000+ cycles at rated stroke
- Natural Frequency: Optimized >100 Hz (application-dependent; contact engineering for FEA prediction under your mass loading)
- Hysteresis: <2% of full-scale stroke
Typical Applications
- Precision instrument vibration isolation — optical table mounts, laser interferometer supports, atomic force microscope (AFM) vibration decoupling
- Thermal expansion compensation devices — cryostat warm-bore connectors, optical bench thermal compensation joints
- Vacuum sensor protection — flexible isolation of vacuum gauges and residual gas analyzers (RGA) from mechanical vibration
- Precision valve actuators — high-cycle gate valve stem seals, proportional control valve bellows for semiconductor gas panels
- Optical system isolation — satellite telescope focus mechanism bellows, airborne laser system vibration decouplers
