Abstract: A nuclear power plant includes a concrete biological shield, a metallic reactor pressure vessel surrounded by the concrete biological shield, coolant connector pieces connected to the reactor pressure vessel, coolant lines connected to the coolant connector piece, and a support engaging the coolant connector pieces and holding the reactor pressure vessel. The support includes at least one supporting tube surrounding one of the coolant connector pieces, the supporting tube having an inner surface anchored on the one coolant connector piece and an outer surface anchored on the biological shield.

Abstract: A nuclear reactor with a cylindrical reactor pressure vessel disposed in a reactor cavity formed in a concrete biological shield surrounding and spaced from the pressure vessel includes means for suspending the reactor pressure vessel from the concrete biological shield, the suspending means being a plurality of tension bolts distributed about the periphery of the cylindrical reactor pressure vessel and secured to a corresponding plurality of brackets attached to the cylindrical reactor pressure vessel, the tension bolts extending from the brackets at an inclined angle through the biological shield.

Abstract: A coolant pump and a steam generator are formed together into a structural unit, the steam generator being a straight-tube steam generator having a central ascending pipe, a tube bundle having a central passageway through which the ascending pipe extends, an upper primary-side inlet, chamber communicating with the tube bundle at an upper end thereof, a lower primary chamber communicating with the tube bundle at a lower end thereof, the central ascending pipe communicating with the inlet chamber for feeding primary medium thereto from which the primary medium flows back through the tube bundle to the lower primary chamber, the ascending pipe having an axial elongation, the coolant pump having an impeller and a guidance device surrounding the impeller, the ascending pipe-elongation having a construction corresponding to that of the guidance device, partition means for dividing the lower primary chamber into a suction space and an outlet chamber space, the pump having a suction side connected through the suction

Abstract: In a nuclear reactor installation secured against rupture and having a pressurized water reactor, a straight-tube steam generator having a central ascending pipe, a coolant pump and lines connecting them in a primary circulatory loop, the coolant pump being installed in a primary chamber of the steam generator and forming with the latter a structural unit, the primary loop having hot and cold lines between a pressure vessel enclosing the reactor and the primary side of the steam generator, at least part of the hot and cold lines being united along the direction of their fluidic flow paths, the structural unit formed of the pump and the steam generator being upright with relatively short, straight and horizontal primary loop lines, and sheathing protective against rupture enclosing the pump, the steam generator and the lines of the primary loop, a tube bundle having a central passageway trough which the ascending pipe extends, an inlet chamber communicating with the top of the tube bundle, an outlet chamber co

Abstract: A pressurized-water coolant reactor installation includes a reactor pressure vessel, a steam generator containing a heat exchanger through which coolant from the vessel is circulated, and a single pipe interconnecting the vessel and generator and internally divided into two conduits for conducting the coolant to the steam generator and from the latter back to the vessel. This single pipe is divided into these two conduits by a partition wall extending longitudinally for the length of the pipe inside of the pipe. This horizontal partition is formed by at least two sections extending radially from the inside of the coolant pipe towards each other and having inner edges spaced from each other and interconnected by an expansion joint.

Abstract: A nuclear reactor pressure vessel is vertically positioned in a concrete reactor pit. The vessel thermally expands and contracts axially and radially. To reduce the possibility of a wall rupture caused by the radial expansion, the top and bottom of the vessel are restrained from movement by the axial expansion, thus placing the vessel's wall under compressive stress in the axial direction. At the top this is done in any prior art manner. At the bottom, the restraint is provided by a series of vertical leaf springs circumferentially interspaced around the vessel's bottom, the lower ends of the springs being fixed to the vessel and the springs extending upwardly therefrom to upper support arrangements. Thus, the bottom of the vessel is suspended by the springs working in tension, while the radial expansion and contraction movements are accommodated by flexure of the springs.

Abstract: A pressurized-water reactor installation comprises a metal pressure vessel surrounded by a concrete wall forming an annular space around the vessel so that the vessel's side wall can be inspected by instrumentation lowered within the space. To provide the vessel with rupture protection, its side wall is encircled by cylindrical segments of pressure-resistant, heat-insulating material, the segments being themselves encircled by high-tensile strength elements. These parts are proportioned so that when the reactor vessel thermally expands, the segments are placed in compression under the restraint of the high-tensile encircling elements which remain cooler than the vessel, and when the vessel is at room temperature, the segments are free from compression and can be removed to clear the annular space around the vessel's side wall and permit use of the instrumentation for the side wall inspection.

Abstract: A pressurized-water coolant reactor installation includes a reactor pressure vessel, a steam generator containing a heat exchanger through which coolant from the vessel is circulated, and a single pipe interconnecting the vessel and generator and internally divided into two conduits for conducting the coolant to the steam generator and from the latter back to the vessel. This single pipe is divided into these two conduits by a partition wall extending longitudinally for the length of the pipe inside of the pipe and having side edges joined with the inside of the pipe, and preferably has a transverse curvature making it laterally deformable when the pipe thermally changes in diameter. Other features are involved.

Abstract: A reactor pressure vessel is supported at its bottom end by an inverted frusto-conical surface concentric with the axis of the vessel and fixed to its bottom, this surface slidably resting on an upright frusto-conical surface which is also concentric with the vessel's axis. Radial thermal movements of the reactor's bottom results in diameter changes in the conical surface fixed to its bottom so that this surface by cam action moves up and down on the other surface, and with a properly defined angularity, compensates for the vertical thermal expansion of the vessel which occurs simultaneously with its radial expansion.

Abstract: A pressurized-water reactor steam generator has a preheater surrounding the cold leg of its U-tube bundle heat exchanger, the preheater discharging being separated by a horizontal partition into upper and lower sections which are each connected with its own feed-water inlet and which respectively discharge the preheated feed water upwardly and downwardly. When the generator is operated under low-load conditions, the feed water supplies are cut off from the two preheater sections, resulting in possible boiling of the water in the preheater because of the lack of circulation through the preheater.

Abstract: A nuclear power plant installation includes a concrete biological shield forming a pit in which a reactor pressure vessel is positioned. A steam generator on the outside of the shield is connected with the pressure vessel via coolant pipe lines which extend through the shield, the coolant circulation being provided by a coolant pump which is also on the outside of the shield. To protect these components on the outside of the shield and which are of mainly or substantially cylindrical shape, semicylindrical concrete segments are interfitted around them to form complete outer cylinders which are retained against outward separation radially from the components, by rings of high tensile steel which may be interspaced so closely that they provide, in effect, an outer steel cylinder. The invention is particularly applicable to pressurized-water coolant reactor installations.