Universal Expansion Joint -- Hinged / Gimbal SS321
Multi-Plane Angular Expansion Joint with Hinge or Gimbal Hardware for High-Temperature Piping
Document No.SV-DS-EXP-004
RevisionRev A
DateMay 2026
ManufacturerSupreme Valves India, Ahmedabad, Gujarat, India
This datasheet covers universal expansion joints with two SS321 bellows, centre pipe, and hinge or gimbal hardware for absorbing large angular movements in high-temperature steam, exhaust, and flue gas piping.
Technical Specifications
| Parameter | Specification |
|---|
| Size Range | DN100 to DN2000 (4" to 80") |
| Pressure Rating | PN10 / PN16 / PN25 / PN40 / Class 150 / Class 300 |
| Bellows Material | SS321 multi-ply hydroformed bellows, 2 to 6 plies |
| Hardware Material | Carbon steel or SS321 hinge pins, gimbal rings, and tie rods |
| Temperature Range | -200°C to +600°C (SS321 limit) |
| Movement Capability | Angular per bellows: up to 15° (hinge) or 10° (gimbal); combined angular: up to 30° |
| End Connections | Flanged ASME B16.5 / BS EN 1092-1 or butt weld ends |
| Hardware Type | Hinge (single-plane) or gimbal (multi-plane) with tie rods |
| Features | Multi-ply SS321, hinge or gimbal, tie rods absorb thrust, internal liner optional |
| Accessories | Internal liner, external shroud, pre-set tabs, insulation pillows |
Materials of Construction
| Component | Material |
|---|
| Bellows | SS321 multi-ply hydroformed bellows, 2 to 6 plies, solution annealed, dye-penetrant tested |
| Centre Pipe | SS321 or carbon steel centre spool piece connecting two bellows assemblies |
| End Pieces | Carbon steel or SS321 pipe sections with weld preparation or machined flange faces |
| Hinge Hardware | Carbon steel or SS321 hinge plates, pins, and bushings for single-plane angular movement |
| Gimbal Hardware | Carbon steel or SS321 gimbal rings and pins for multi-plane angular movement |
| Tie Rods | Carbon steel or SS321 threaded tie rods with double nuts and washers to absorb pressure thrust |
| Internal Liner | SS321 thin-wall liner with drain holes for high-velocity or particulate-laden gas streams |
| External Cover | SS304 or carbon steel protective shroud for personnel protection and insulation retention |
Testing & Inspection
| Test | Requirement |
|---|
| Test Standard | Hydrostatic 1.5x PN; helium leak test on bellows; angular movement witness test |
| Certification | CE, PED, ISO 9001 |
Applicable Standards
| Standard | Description |
|---|
| Design Standard | ISO 10628 / BS 6129 / EJMA Standards |
Notes
- Hinge expansion joints must be installed with hinge axis perpendicular to the plane of intended angular movement; gimbal joints allow any plane.
- Tie rods must be pre-tensioned during installation to absorb pressure thrust; do not loosen or remove tie rods during operation.
- For high-velocity steam or gas with particulate, specify internal liner to prevent bellows erosion and flow-induced vibration.
- Bellows fatigue life depends on angular movement per convolution; specify total expected angular movement and design temperature at order.
- Pre-set tabs may be used to position bellows at neutral angle during installation; remove after piping is complete and system is pressurised.
