Abstract: The invention concerns the production of ceramic-metal multilayer components comrising effecting, after making up in the crude state, in particular by metallization and stacking of pre-cut raw ceramic bands, a simultaneous firing operation, termed cofiring, on the components under an atmosphere based on hydrogen or nitrogen or a mixture of hydrogen and nitrogen, having a regulated water vapor content at a temperature of first of all between 800.degree. C. and 1800.degree. C., and more precisely either at a moderately high temperature plateau between 800.degree. C. and 1300.degree. C. for certain ceramic materials such as codierite and metallic materials such as copper and nickel, or at a temperature plateau between about 1400.degree. C. and 1800.degree. C.

Abstract: The invention concerns glass-metal sealing comprising effecting on a metallic piece, in particular an alloy based on iron and nickel or iron, nickel and cobalt, first of all a decarburization under an atmosphere, at a temperature of between 950.degree. C. and 1,150.degree. C., formed by hydrogen (10 to 99%), water vapor (1 to 8%), with a ratio hydrogen/water vapor higher than five, the possible remainder being nitrogen, then an oxidation under an atmosphere formed by an inert vector gas such as nitrogen, either at a temperature of 600.degree. C. to 800.degree. C. and with a water vapor content of 8% to 2%; or at a temperature of 900.degree. C. to 1,100.degree. C. and with a water vapor content of 4% to 0.5%; then establishing the connection.

Abstract: A larger number of keys (L) are formed in the outer cylindrical surface of a rotor rim than is strictly necessary for fixing pole pieces (P) thereto. The keys are regularly spaced around the rim. This arrangement makes it possible to avoid having adjacent rim segments offset to each other by an angle which is equal to the pole pitch or at best to the half pole pitch as has previously been the case. The overlap between segments may now be at the pitch of the fixing keys. This can be used to increase the overlap factor, thereby increasing the mechanical strength of the rim against centrifugal forces.

Abstract: The front portion (116) of the immersed turbo-generator bulb houses the alternator (5, 19). The intermediate portion (114) houses the gear box (26), and the rear portion has the turbine (122 projecting therefrom. The intermediate portion is of greater diameter than the front portion and they are interconnected by a flange (2). The external cooling is by tubes (7) through which cooling air flows, and having one end connected to orifices through the flange (2).