Our Products
Rectangular Bellows
Rectangular metallic bellows/expansion joints are engineered for ducts and non-circular sections handling thermal growth and vibration. Available with mitered or rounded corners and various profiles (U / V / Ω), they manage axial and lateral movement within space-constrained layouts. Designed and manufactured by Athulya Bellows per EJMA/ASME practices for reliable service.
Key Features
• Built to suit rectangular/oval ducts, hoppers, and equipment cases.
• Corner options: mitered (with corner reinforcement) or rounded (formed corners).
• Profiles: U / V / Ω corrugations; single or multi-ply bellows for fatigue life.
• End frames: angle or channel frames; flanged or weld-in construction.
• Optional internal liners for velocity/particulate; external covers/insulation.
• Can be supplied with tie/limit rods where thrust restraint is required.
Applications
• Air/gas ducts in power, steel & cement plants; fans, blowers, ID/FD ducts.
• Process & thermal ducts in refineries, petrochemical & chemical plants.
• Large HVAC/district heating/cooling rectangular mains and plenums.
Technical Data
| Parameter | Value / Range | Notes |
|---|---|---|
| Section Size (W × H) | Project-specific | Engineered to duct dimensions |
| Pressure Class | As per design/service | Low to moderate for ducts; thrust restraint if needed |
| Temperature | Material/service dependent | Grade & liner selection per medium & temp |
| Movement Capability | Axial / Lateral (project-specific) | Preset/cold-spring available |
| Corner Type | Mitered / Rounded | With corner reinforcement as required |
| Profile & Ply | U / V / Ω; single or multi-ply | Selected for flexibility & cycle life |
| Materials | SS 304 / 316 / 321 / 310; special alloys | Frames/hardware in CS/SS; coatings available |
| End Connections | Flanged / Welded (angle/channel frame) | Drilling to ANSI/EN/IS or client standard |
| Accessories | Internal liners, external covers, tie/limit rods | Shipping rods removed at install |
Design Options
• Multi-ply bellows for higher flexibility & fatigue life.
• Control units (tie/limit rods) with clevis/spherical ends.
• External covers and insulation jackets; surface protection for CS parts.
• Factory preset / cold-spring to optimize installed capability.
Quality & Testing
• Designed and manufactured per EJMA/ASME practices.
• Hydrostatic / pneumatic pressure testing as applicable to service.
• Optional NDT: dye-penetrant, helium leak, and cycle testing.
• Full material traceability with certificates on request.
Prefer a quick review? Email your specs to sales@athulyabellows.com.