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An expansion joint is a device that allows movement in a piping system, while containing pressure and the medium running through it.

Besides acting as a section of a pipe, it is capable of withstanding the design temperatures, pressures, and media, also providing the flexibility that makes them necessary. That flexibility can be axial, lateral or angular. However, in many installations, some rigidity or structural strength is needed to support piping loads or control the motion of the bellows and the pipe. Thus, features, like pipe, flange, limit rods, tie rods, internal sleeve (liner), shroud (external cover), are then added to the expansion joint.

Various calculations are used to determine the theoretical life expectancy for a given design. EJMA (Expansion Joint Manufactures Association) is the predominant standard used. The expansion joint manufacturers who make up EJMA are today's leading authorities on expansion joint design.

Bellows: A bellow is a thin walled flexible element of the expansion joint. Each bellows has a unique working pressure, spring rate, and cycle life that are entirely dependent on its geometry and material. All customers should insist that their bellows be manufactured in accordance with these standards. The bellows has several corrugations called convolutions that allow movement in axial, lateral and angular directions.


  • Designed and manufactured as per E.J.M.A. and A.S.M.E. codes, section III & VIII
  • Computerized detail stress analysis with cycle life.
  • Single and multiply construction.
  • Single, Double, Universal, Gimbal, Hinged and Pressure balanced construction.
  • Specialized Instrumentation Bellows for highly flexible application.