Product Overview
The Long Travel Motion Control Edge Welded Bellows is purpose-engineered for precision motion applications in vacuum environments — where high stroke, low friction, and micron-level repeatability are simultaneously required. With an extended diaphragm count and optimized convolution geometry, this bellows delivers ±20–30mm of smooth, linear axial travel — the longest stroke in our standard product line — while maintaining the vacuum integrity and spring rate consistency that precision positioning demands.
This is the bellows of choice for vacuum-compatible motion systems: wafer probing stations, in-vacuum robots, beamline sample manipulators, and deposition chamber translation stages. The ultra-low friction of the all-metal edge welded design eliminates stick-slip, and the precisely controlled spring rate (±5%) ensures predictable actuation force throughout the stroke. For detailed dimensional data, see the long-travel range in our AT-Series Catalog.
Key Benefits
- Industry-leading stroke capability — ±20–30mm from a compact form factor, achieved through high diaphragm count and optimized convolution depth; up to 60% compression of free length
- Smooth, low-friction motion — all-metal edge welded construction with electropolished surfaces eliminates the stick-slip behavior of elastomer-sealed alternatives; no breakaway force spike
- Micron-level repeatability — ±0.01mm positioning repeatability when paired with closed-loop control, enabled by the bellows’ linear spring rate and zero backlash
- High cycle life for continuous operation — 1 million+ cycles at rated stroke; designed for 24/7 automated motion in semiconductor manufacturing environments
- Excellent lateral stability — reinforced end convolutions resist buckling and torsional deflection even under off-axis loading, maintaining straight-line motion without side contact
- Motion speed up to 100mm/s — suitable for high-throughput pick-and-place and rapid scanning applications
Technical Specifications
- Material: SS316L Stainless Steel — AM350 available for maximum fatigue life (see Material Selection Guide)
- Vacuum Level: 10⁻⁸ mbar (standard); UHV 10⁻¹⁰ mbar with copper gasket option
- Operating Temperature: -196°C to +300°C (SS316L)
- Axial Stroke: ±20–30mm (application-dependent; longer custom strokes available)
- Cycle Life: 1,000,000+ cycles at rated stroke
- Motion Speed: Up to 100mm/s (higher on request with specific cycle life trade-offs)
- Repeatability: ±0.01mm (when properly integrated with linear guidance)
- Spring Rate Tolerance: ±5% (factory-measured and reported per unit)
- Surface Finish: Electropolished (Ra ≤ 0.4μm) standard
Typical Applications
- Semiconductor wafer probe stations — precision Z-axis motion for electrical test probing under vacuum
- Vacuum manipulator joints — beamline sample transfer arms, wobble sticks, and precision goniometers
- In-vacuum robot systems — wafer handling robots, cluster tool transfer modules, OLED deposition automation
- Precision vacuum positioning devices — translation stages for in-situ thin-film measurement, laser alignment systems
- Vacuum translation stage drives — linear motion feedthroughs for deposition masks, shutter mechanisms, and beam stops
