Universal expansion joint with short tie rods (HHXL)

Universal expansion joint with short tie rods is one consisting of two bellows connected(joined) by a common connector or centre piece for the purpose of absorbing any combination of the three basic movements: Axial compression and extension; Lateral movements; Angular deflection. Universal Expansion Joint are usually furnished with control rods to distribute the movement between the two bellows of the expansion joint and stabilize the common connector. The definition does not imply that only a universal expansion joint can absorb combined movement. Double expansion joint is different from Universal expansion joint.
 
A universal expansion joint can be designed to have a very low lateral spring force to minimize forces on adjacent equipment. A two tie rod design can also accept angular deflection in a single plane. The tie rods are usually at or near ambient temperatures and, therefore, do not expand and contract as a function of the temperature of the media within the pipe. As a result, the thermal expansion of the length of pipe between the tie rod end plates is forced into the bellows as an axial movement. The bellows design must accommodate this axial thermal expansion as well as the specified lateral movement. Sometimes a universal expansion joint has a very heavy centre spool that can exert excessive weight on the bellows elements. To protect the bellows elements from excessive lateral loads, a support system such as a slotted hinge can be installed across the individual bellows elements to support the dead weight of the centre spool.

Advantages:
1. Simple and robust construction.
2. Absorbs large amount of lateral, angular and axial movements...
3. Inexpensive.
4. Easy to install
5. Low maintenance
B) Disadvantage
-The changed flow direction