Patent ID: 7314024

Claim:
Steam generator comprising an outer jacket ( 2 ) of generally cylindrical shape arranged with its vertical axis having a lower cylindrical part ( 2 a ) containing a bundle ( 3 ) of heat exchange tubes connected to a primary fluid circuit and arranged in a bundle wrapper ( 4 ) which is substantially coaxial with the outer jacket ( 2 ), an upper cylindrical part ( 2 b ) having a diameter greater than the diameter of the lower part ( 2 a ) in particular containing separators and steam dryers ( 15 ) and a part ( 2 c ) with a frustoconical junction between the lower part ( 2 a ) and the upper part ( 2 b ) of the outer jacket ( 2 ), at least a first and a second device ( 8 , 16 ) for supplying feed water to an annular space ( 7 ) between the bundle wrapper ( 4 ) and one of a guide skirt ( 13 ) and the outer jacket ( 2 ), via the upper part of the annular space ( 7 ) which communicates with the inner space of the bundle wrapper ( 4 ) at its lower part, each one comprising a feed water distribution header ( 10 , 17 ) in the annular space ( 7 ) arranged inside the outer jacket ( 2 ) having a toroidal wall substantially coaxial with the outer jacket ( 2 ) and with the bundle wrapper ( 4 ), the toroidal wall being penetrated by a plurality of openings for the passage of water into its upper part and at least one feed water supply pipe ( 9 , 19 ) in a space inside the toroidal wall of the header ( 10 , 17 ) penetrating the outer wall ( 2 ) of the steam generator ( 1 ), the first feed device ( 8 ) being used during normal operation of the steam generator ( 1 ) and the second feed device ( 16 ) being used in order to feed the steam generator ( 1 ) with emergency water, characterized in that the second toroidal header ( 17 ) of the second emergency feed water device ( 16 ) placed inside the upper part ( 2 b ) of the outer jacket ( 2 ) comprises, fastened to each of its openings ( 21 ) for the passage of water from its toroidal wall, a tube ( 22 ) for injecting water having an open lower end part ( 22 a ) fastened to the opening ( 21 ) of the toroidal wall, a straight part ( 22 b ) which is inclined with respect to the vertical axial direction in the direction of a central part of the steam generator ( 1 ) and an upper end open at the end of the straight part ( 22 b ) of the tube ( 22 ) for injecting emergency water inside the steam generator ( 1 ).