Bellows with Internal Shafts
Design Features:
- Integrated precision-ground shaft running through bellows center
- Hermetic seal between shaft and end plates
- Anti-rotation keyways or splined shafts
- Custom shaft materials: hardened steel, stainless, or ceramic
Benefits:
- Eliminates external linkages
- Maintains alignment in rotary/linear systems
- Transmits torque through sealed environment
- Reduces system footprint
Typical Applications:
- Vacuum rotary feedthroughs
- Hermetic actuators
- Medical device drives
- Semiconductor wafer handling
Extended Length Bellows with Isolation Rings
Design Features:
- Modular construction with intermediate isolation rings
- Ring spacing every 5–15 convolutions
- Rings manufactured from compatible materials (stainless, Inconel)
- Optional cooling channels in rings
Benefits:
- Prevents column buckling in long strokes
- Maintains uniform compression
- Distributes stress evenly
- Allows thermal management
Technical Specifications:
| Max. unsupported length | 2 meters |
|---|---|
| Isolation ring spacing | 50–150 mm |
| Ring thickness | 1–5 mm |
| Max. compression ratio | 40% |
Bellows with Integrated Guide Rods
Design Features:
- Precision guide rods parallel to bellows axis
- Linear bearings integrated into end plates
- Adjustable preload mechanisms
- Corrosion-resistant rod materials
Benefits:
- Eliminates lateral deflection
- Maintains axial alignment
- Prevents torsion during operation
- Increases cycle life by 300%
Configuration Options:
- Single-rod center guide
- Dual-rod opposed configuration
- Quad-rod box guidance system
- Telescoping multi-stage guides
Material & Construction
Bellows Core: 316L, Inconel 718, Hastelloy C-276
Shafts: 17-4PH stainless, titanium
Guide rods: Hard-chromed steel, alumina ceramic
Isolation rings: Matching or dissimilar metals
Welding: EB/TIG welding under argon atmosphere
Finishing: Electropolishing, passivation, UHV cleaning
Custom Design Process
Application Analysis:
- Motion requirements (stroke, speed, cycles)
- Environmental conditions (temp, pressure, media)
- Space constraints and interface points
Engineering Solution:
- FEA analysis for stress distribution
- Buckling calculations for extended lengths
- Wear simulation for guide systems
Prototype Development:
- Functional prototype within 4 weeks
- Validation testing report included
Production:
- Dedicated tooling for custom components
- Lot traceability with material certifications
Technical Advantages
- Precision Alignment: ≤0.05mm runout in guided systems
- Extended Stroke: Up to 1.5m travel with isolation rings
- Load Capacity: Guide rods support up to 500kg axial load
- Vacuum Compatibility: ≤10⁻¹⁰ mbar·L/sec leak rate
- Temperature Range: -270°C to +800°C (material dependent)
How to Order Specialized Bellows
Provide these specifications:
- Primary function (motion transfer, isolation, guidance)
- Dimensional constraints (OD, ID, min/max length)
- Motion parameters (stroke, speed, cycles)
- Environmental conditions
- Special requirements:
- Shaft type (solid/hollow, connection method)
- Guide rod configuration
- Isolation ring spacing
- Surface finish requirements
Lead Times:
- Standard specialized designs: 6–8 weeks
- Fully custom solutions: 8–12 weeks
Volume Production:
- Dedicated production lines for OEM quantities
- Annual volume discounts available
For complex applications, request our engineering consultation service for system-integrated solutions.