They are manufactured by two bellows linked together by an intermediate pipe and equipped with a tie rod that allows only the lateral movement, preventing the axial one.

They resist pressure thrust caused by internal pressure.

They are generally used to eliminate the thrust power due to the fixing points’ stress, and to compensate remarkable lateral movements.

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.