Abstract: Recirculation-type steam generator ensuring heat transfer between a fluid circulating in a primary circuit and a fluid circulating in a secondary circuit, constituted by a pressure envelope containing a vaporization enclosure having a roof and covering a bundle of tubes traversed by the primary fluid. The generator receives the secondary fluid which circulates in the vaporization enclosure. The steam produced by the secondary fluid is extracted during this circulation and is dried by cyclone separators constituted by cyclones fixed to first ends of tubular columns whose ends are fixed to the vaporization enclosure roof communicating with the vaporization enclosure. The cyclone separators are detachably fixed to the vaporization enclosure roof.

Abstract: In a heat exchanger such as a steam generator equipping a nuclear power station the secondary fluid is injected into the upper part of an annular space (30) formed between an outer envelope (10) and a bundle or core envelope (26) having a common vertical axis. Injection takes place by means of a supply pipe (44), which issues into an overflow or weir (62). The latter has an upper horizontal edge (64) from which the secondary fluid is discharged onto a deflecting wall (54). The secondary fluid flows along this wall towards the bottom of the annular space (30). A device (60) for trapping migrating bodies can also be placed in the overflow (62) or between the latter and the deflecting wall (54).

Abstract: A device for trapping migrating bodies within the steam generator or secondary circuit of a nuclear installation is constituted by grids (6) placed between the upper part of the tube casing (8) and the pressure casing (7) of the steam generator. The meshes of the grids are so dimensioned as to prevent the passage of objects liable to jam between the tubes of the tube bundle of the primary circuit.