There are certain applications where a huge amount of axial movement has to be compensated.

An internally pressurized Expansion Joints with more number of convolutions to compensate the required axial movement is totally unstable even under small pressure.

Externally Pressurized Expansion Joint, in which the flow medium pressure is guided external to the Bellows, is an ideal solution to compensate huge axial movement.

Since the Bellows inside is subjected to only atmospheric pressure, there is no instability or squirm.