Gas Spring Bellows
The figure shows the two designs of bellows, the Convoluted Tube Gas Spring Bellow and the Rolling Lobe Gas Spring Bellow or U Bellows. Similar to a tire, the gas spring bellow is composed of rubber material reinforced by textile fabric.
The cross-sectional area of the pneumatic spring exposed to the positive pressure, which produces a force on the vehicle structure, is called effective area of cross-section Aw. In contrast to the above mentioned hydropneumatic gas spring, the effective area of cross-section Aw of the gas spring bellow changes proportional to its travel.