Hinged Bellows Expansion Joints
A hinged expansion joint is designed to permit angular rotation in only one plane by using a pair of pins through hinge plates attached to each end of the expansion joint. Hinge hardware and pins are designed to restrain pressure thrust of the bellows and any extraneous forces where applicable.
Hinged expansion joints must be used in sets of 2 or 3 to function properly and they do not need to be co-linear.
Advantages of Hinged Expansion Joints:
- Ability of hinged expansion joints to transmit loads helps to simplify supporting a hinged piping system. Such systems may be supported at virtually any point which does not interfere with the free movement of the system.
- Systems of hinged expansion joints may be used in other than 90 degree bends.
- A hinged expansion joint system may be used effectively in applications involving movement other than the pure thermal growth of piping.
- Hinged expansion joints are compact and they have high structural rigidity.
- It is usually possible to compensate for the thermal expansion of irregular and complex piping configurations which might preclude the use of other type of expansion joints.
- Since hinge structures have the ability to transmit loads, piping systems containing hinged expansion joints impose minimum forces on the pipe anchors.
- Hinge hardware can be designed to eliminate torsion or twisting about the expansion joint longitudinal axis.
Additional Types of Hinged Expansion Joints:
- Slotted Hinged Expansion Joint allows axial movement but it does not continuously restrain pressure thrust of bellows.
- Universal Hinge Expansion Joint.