The following list shows some typical causes of Metallic Expansion Joint failure:
- Shipping and handling damage like denting or gouging of bellows from being struck by hard objects (tools, chain falls, forklifts, adjacent structures, etc.); improper stacking for shipping or storage; insufficient protection from weather or other adverse environmental conditions.
- Improper installation and insufficient protection.
- Expansion Joints with internal liners installed in the reverse direction with respect to flow.
- Installing an expansion joint in a location other than as prescribed by the installation drawings.
- Premature removal of shipping devices.
- Springing of bellows to make up for piping misalignment.
- Insufficient protection from mechanical damage due to work in the surrounding area.
- Insufficient protection of bellows during nearby welding operations.
- Failure to remove shipping devices before placing system in operation.
- Improper anchoring, guiding and supporting of the system.
- Anchor failure in service.
- Bellows corrosion, both internal and external.
- System over-pressure (in-service or hydrotest).
- Bellows vibration (mechanical or flow induced resulting in high cycle fatigue).
- Excessive bellows deflection (axial, lateral, angular deflections greater than design values).
- Torsion.
- Bellows erosion.
- Packing of particulate matter in the bellows convolutions which inhibit proper movement of the bellows.
