• Axial Deflection
  • Axial Movement Examples
• Lateral Deflection
  • Lateral Movement Examples
• Angular Deflection
  • Angular Movement Examples
• Combined Deflections
  • Combined Movement Examples
• Torsional Deflection
• Cyclic Deflections
• Pressure Balancing Examples
• Hinged or Gimbal Examples
•  

Axial refers to being parallel to the centerline of the expansion joint.  Compression is the axial deflection which will shorten the bellows length.  Often confusion occurs because thermal expansion in the piping will cause the expansion joint to be compressed.  The specification for an expansion joint should always state the movements as they affect the expansion joint, and not as they are produced by the system.

Extension is the axial deflection which stretches the expansion joints.  Piping which is operating at temperatures lower than ambient, such as in cryogenic systems, will contract causing the expansion joint to stretch or experience extension.