They are manufactured by a single bellows with regulating and dismantling tie rods.

Usually, they do not absorb any expansions and are used to allow the dismantling of valves or other equipment installed on the pipeline near the joint itself.

They do not resist pressure thrust caused by internal pressure but can be supplied with bolt tie rods which dimension is designed to support the thrust caused by pressure clamping the joint in the absence of fixing points.

Moreover, they can also be manufactured with steel bellows or special alloys, according to their use, for example AISI 316Ti, AISI 310, HASTELLOY, INCONEL, AVESTA 904L, MONEL 400, INCOLOY, and with the ends in special materials like CORTEN, A335 P11, A333 Gr.6 and others upon request.