DFS Type
expansion joints
DFS Type
expansion joints
DFS type with tie rods
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
| 3 | Reinforcement ring |
| 4 | Loose brackets |
| 5 | Tie rods |
| 6 | Nuts |
| 7 | Spherical washers |
DFS Type
expansion joints
Features
- Transportation or piping systems that carry fluids, slurries or gasses under pressure or vacuum at varying temperatures
- Reduction of vibration
- Dampen sound transmission
- Compensate movements due thermal changes, misalignments caused by wear, load stresses, settling of supporting foundations
- Molding and manual production.
- Standard measures (length)
Advantages
- Easy installation
- Flanges are not in contact with medium, which enables lower grade material
- Galvanic surfaces / coatings possible
- Gaskets can be eliminated
- Additional movement capabilities
- Special measures (length, diameter, flanges) → custom made
- Different models (hose, reduction, multiple arches, filled arch, spool, …)
- Higher design pressure
- Special designs (spring rates, different inner and outer layers)
Materials
- Bellows: Various elastomers such as EPDM, EPDM Food Grade, Neoprene, Nitrile, Hypalon, Butyl, Viton
- Flanges: carbon steel and stainless steel.
Other materials are available on request.
Standards and approvals
NDT and documentation: Can be provided per customer request e.g. Material Certificates and NDT test reports.
Recommended applications
- Air conditioning, heating and ventilating systems in industrial buildings and vessels
- Central and ancillary power generating stations in industrial buildings, factories, ships and offshore applications
- Sewage disposal and water treatment plant, pumps, etc.
- Process piping in pulp and paper plants
- Piping systems for chilled or hot water
- Cooling systems for power generation
- Feed water and draining lines for water works, sewage, sanitary piping systems etc.
- Oil lines for industrial plants, shipyards, phosphate plants etc.
Product variants
DFS type double/multiple arch
Higher maximum movements, lower spring rates.
DFS type PTFE liner
High temperatures or chemical attack. Not recommended for negative pressure.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
| 3 | Reinforcement ring |
| 4 | PTFE liner |
DFS type reduction (conical)
Connection between different DNs.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
| 3 | Reinforcement ring |
DFS type spool
Installation with clamping bands. Maximum pressure 1 -2 BarG.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Reinforcement ring |
DFS type filled arch
To avoid deposits in the arch area. Reduced movements and higher spring rates. Not recommended in case of negative pressure.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
| 3 | Reinforcement ring |
| 4 | Filler |
DFS type elbow
With or without arches.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
DFS type pressure balanced
In line or elbow construction. No transmission of pressure thrust with absorbtion of axial and lateral movements.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
| 3 | Reinforcement ring |
| 4 | Flanges |
| 5 | Nuts |
| 6 | Rubber bellows |
DFS type rectangular
Only for low pressure.
| Item | Designation |
| 1 | Rubber bellows |
| 2 | Flanges |
DFS type dog bone
On condensers in central power stations.
DFS type wall seal
For axial, angular and lateral movements. Pressures up to 2,5 BarG
DFS type diamantling joints
To allow dismantling of equipment for maintenence purposes.
Similar products
D Type expansion joints
- Transportation or piping systems that carry fluids, slurries or gasses under pressure or vacuum at varying temperatures
- Reduction of vibration
- Dampen sound transmission
- Compensate movements due thermal changes, misalignments caused by wear, load stresses, settling of supporting foundations
- Molding production with long radius arch
- Standard measures (length)
Rubber Hose Type expansion joints
- Transportation or piping systems that carry fluids, slurries or gasses under pressure or vacuum at varying temperatures.
- Reduction of vibration
- Dampen sound transmission