Abstract: A bellows for connecting hoses or apparatus operating in a partial vacuum including a corrugated tube reinforced on the outside by rings at the troughs of the corrugations. The tube further includes toric reinforcing rings on the inside of the crests of the corrugations, the length of the rings being adjustable so as to adapt to the deformation of the corrugations in service.

Abstract: A magnetically drive centrifugal pump comprises a fixed assembly formed by a pump barrel made of a carbonaceous material, rigid annular bearings and a non-magnetic, non-electrically conductive sealing shell, and a rotating assembly formed by an impeller made of a carbonaceous material, a cylindrical rotor made of a carbonaceous material and having sealed therein permanent tracking magnets. The rotor is fixed directly to the impeller to form an impeller-rotor assembly which rests on the annular bearings. The driver includes magnets which interact with the permanent tracking magnets of the rotor in order to drive the pump, the driver being isolated from the impeller-rotor assembly by the sealing shell. The impeller-rotor assembly includes a secondary circuit for circulation of transported fluid located between the impeller-rotor assembly and the sealing shell.