Product Overview
The Medium Round Flange Edge Welded Bellows is our most versatile standard product — the workhorse of the Alpha Technology lineup. Striking an optimal balance between compact form factor and generous stroke capability, this bellows is specified by system integrators across semiconductor, vacuum coating, and industrial furnace applications. Its multi-diaphragm stack design provides exceptional axial, angular, and lateral compliance, making it the go-to solution for connecting rigid vacuum piping where thermal expansion, misalignment, and vibration must be absorbed.
Every unit is helium mass spectrometer leak tested to verify integrity before shipping. For this model’s exact OD/ID dimensions across multiple sizes, refer to the medium-range entries in our AT-Series Specification Catalog. Custom flange drilling patterns, non-standard bolt circles, and alternative materials are available on request — see Process & Design for our engineering workflow.
Key Benefits
- Best-selling standard configuration — proven in thousands of installations worldwide, with short lead times and competitive pricing
- Multi-diaphragm edge welded stack provides superior flexibility compared to single-convolution or hydroformed alternatives — up to 60% compression of free length
- All-metal, elastomer-free construction — fully bakeable to 350°C for UHV conditioning; no organic materials to outgas or degrade under radiation
- Excellent multi-axis motion compensation — ±12mm axial, ±8° angular, ±5mm lateral offset handled simultaneously without compromising leak integrity
- 1 million+ cycle fatigue life under rated stroke conditions — dramatically reduces maintenance intervals compared to elastomer-sealed alternatives
Technical Specifications
- Flange Type: Standard Round Flange (CF, ISO-K, ISO-F, and custom bolt patterns available)
- Material: SS316L Stainless Steel — AM350 and Inconel 718 options in Material Selection Guide
- Vacuum Level: 10⁻⁸ mbar (standard); UHV 10⁻¹⁰ mbar with copper gasket sealing
- Operating Temperature: -196°C to +350°C (standard); up to 700°C with Inconel 718
- Axial Stroke: ±8–12mm (compression-dominant; extension limited to ~25% of free length)
- Angular Deflection: ±8°
- Parallel Offset: ±5mm
- Cycle Life: 1,000,000+ cycles at rated stroke (application-validated; contact engineering for life prediction under your specific conditions)
Typical Applications
- Semiconductor process equipment — PVD/CVD chamber exhaust lines, wafer transfer module vacuum connections
- Vacuum coating and thin-film deposition — thermal evaporation, sputtering, and ion beam deposition systems
- Industrial vacuum furnaces — brazing, sintering, and heat treatment furnace vacuum piping
- Research laboratory installations — beamline vacuum transport, cryostat warm-bore connections
- Vacuum packaging machinery — food and pharmaceutical vacuum sealing equipment
