Abstract: A superheater bundle for a horizontal steam separator-superheater, the bundle comprising an array of parallel tubes disposed in a triangular pitch inside a frame (3, 4) which is polygonal in shape and symmetrical about its plane of symmetry, with the bottom of the frame delimiting an inlet orifice for steam to be superheatd and with the top of the frame delimiting an outlet orifice for superheated steam. At least two of the sloping sides (11, 13, 15, 15, 17; 12, 14, 16, 18) of th polygon-shaped frame (3, 4) are parallel to the sloping segments formed by the pitch of the tubes.

Abstract: A vertical heat exchanger adapted to be located between a primary liquid alkali metal circuit and a secondary liquid alkali metal circuit in a fast neutron nuclear reactor is disclosed. The exchanger includes an outer sleeve surrounding an annular tubular bundle on an axial conduit for introduction of the secondary liquid alkali metal in the tubes through a chamber provided in the bottom of the exchanger. The bottom of the exchanger is surrounded by an envelope defining a space in which the primary liquid alkali metal circulates between an annular opening provided at the periphery of the tubular plate carrying the tubular bundle and at least one output opening in the bottom of the envelope.