AU Universal Expansion Joints

FIT, FORM and FUNCTION

Universal expansion joints are designed to accommodate large amounts of lateral movement in addition to axial displacement, making them particularly suitable for complex piping layouts where direction changes are frequent. Unlike standard expansion joints, universal types feature two bellows separated by a center pipe spool, allowing for greater flexibility in managing multidirectional movements.

AU – Universal Expansion Joint fit:

Bellows may be attached or linked to piping flanges, pipe, or other typical industrial connections.
End connections may conform to standards such as ASME B16.5, ASME B36.10, or customer designed.
Fittings generally not the same at all locations: interface connections may be as noted above. Connections within the assembly are typically to pipe.

AU – Universal Expansion Joint form:

Two circular metal bellows, each with 1 or more convolutions.
Typical dimensions of 1⁄2” ANSI NPS to 240” ID. Overall length may vary, typically within the range of 18” to 240”.
Bellows may include reinforcement or controlling members.
Convolutions may be U shaped or toroidal
Additional accessories may be incorporated such as load bearing restraints, movement limiters, protection on devices

AU – Universal Expansion Joint function:

Absorbs movement, primarily perpendicular to the complete assembly (lateral) but often includes axial and/or angular movements
Movement amplitude varies, typically within the range of 1/2” to 20”.
Movement frequency may be extreme low cycle (1 per year), or high cyclic (such as vibration at 60 Hz)

Metal Bellows Catalog

Catalog

This catalog contains excellent technical references to help you understand how expansion joints work, how to apply them, and how to select the expansion joint best suited for your application.

INDUSTRIAL APPLICATIONS

They are commonly used in district heating and cooling systems with intricate network configurations, as well as in power generation plants where thermal cycles induce both lateral and axial stresses. In chemical processing and petrochemical facilities, universal expansion joints excel in protecting piping systems that experience simultaneous pressure fluctuations and directional shifts. Marine applications also benefit from their ability to absorb vibrations and movements caused by both temperature changes and vessel motion, ensuring the reliability and safety of onboard systems. In pulp and paper mills, universal joints help maintain system integrity in areas with complex process routing and frequent temperature variation.