This is the simplest and most common type of round metal expansion joint.
Pressure thrust must be contained by the piping system since the expansion
joint has no mechanism to contain it.
Single Tied Bellows
The addition of tie rods allows pressure thrust to be contained if the
piping system is relatively flexible. If the piping system is very
rigid, the tie rods do not contain pressure thrust but rather act as a
safety device in the event of failure of a system anchor.
Single Hinged Bellows
This type of expansion joint absorbs only angular movement in one plane.
Pressure thrust is completely contained.
Slotted Hinged Bellows
This type of expansion joint allows angular movement in one plane plus axial
compression. It does not contain pressure thrust.
Gimbaled Bellows
This type of expansion joint allows angular movement in two planes. It
cannot accommodate axial or lateral movement. Pressure thrust is
completely contained.
