Lateral expansion joints
Lateral expansion joints absorb movements vertical to the bracing plane. The reaction forces caused by the internal pressure are absorbed by the joint mounting.
Under internal pressure expansion joints generated pressure reaction forces.
For a better understanding, the following considerations with different diamaters, pressures and resulting from it the forces:
- DN 150 -> 25 bar ~ 80 kN = 8 t
- DN 300 -> 10 bar ~ 100 kN = 10 t
- DN 1000 -> 1.5 bar ~ 130 kN = 13 t
Due to high forces, movements in pipelines of higher nominal size and higher pressure can only be absorbed with braced expansion joints. Applying braced expansion joints pressure stress can be absorbed, while fixed bearings can be dimensioned smaller. In case a 3-hinge-system cannot be applied due to missing space, special-purpose solutions like pressure-balanced expansion joints can be installed.
Types of design for lateral expansion joints:
- ball bearing types with tie rods for all-side movements
- cross hinged types for all-side movements and higher pressure