Abstract: A supporting floor for the core of a nuclear reactor utilizes a plurality of independent support columns forming the floor of the reactor and resting on the bottom layers of the reactor. The support columns are surrounded by a side reflector which is in turn surrounded by a thermal side shield. Between the thermal side shield and the side reflector are disposed retaining means for maintaining the columns close together and preventing the formation of large gaps during operation.

Abstract: An inspection device for the inspection of internal spaces in nuclear reactor installations requires extremely small dimensions while being capable of use at high temperatures and exposures to radiation during shutdown periods of the reactor. The device is designed so that it is readily adapted to a particular inspection purpose. The particular device meeting these requirements comprises a camera arranged in a tube and cooled in such tube. The objective of the camera and/or a mirror are each connected with means for relative movement. A source light and the movement means are designed as separate structural elements which may be assembled in different combinations in a modular fashion.

Abstract: An apparatus for measuring the flow of gas in a blower of a gas cooled high temperature nuclear reactor comprising a blower, a blower shield communicating with the blower, an inlet conduit in the blower shield for conducting gas flow to the blower, an exit conduit in the blower shield for conducting gas flow from the blower and means for measuring the flow of gas in the exit conduit. The measuring means includes a venturi tube having a narrowed area in the exit conduit, a first measuring channel in communication with the gas flow in the narrowed area, a second measuring channel in communication with the gas flow in the exit conduit upstream from the narrowed area, and means for comparing the relative gas flow in the first and second measuring channels. A transducer connected to the first and second measuring channels performs the comparing and measuring steps.

Abstract: A mounting for power conductor and instrument lead penetrations in nuclear reactors provides a device that is simple, compact and at the same time easily installed, repaired or replaced. The mounting comprises a cylinder like, stepped housing which is to pass through the pressure vessel wall of the nuclear reactor and house at least one and preferably a plurality of electrical conductors.

Abstract: The invention concerns a vaulted cover to close a vertical recess in a pressure vessel with a plurality of fittings welded to the cover for the passage of steam pipes and with heat insulation applied to the inside of the cover consisting of a thermally insulating material and a plurality of rectangular cover plates arranged on the thermally insulating material, wherein the cover plates are fastened to the cover by means of holding bolts penetrating the entire insulation.

Abstract: The leakage of gases in gas cooled nuclear reactors is detected by an arrangement utilizing a flexible material to cover areas of potential leakage and create detection cavities inside the concrete vessel of a nuclear power plant. The detection cavities are connected to the gas collector housed within the concrete vessel by means of gas-tight connecting conduits or lines. A negative pressure is applied to the gas collection device connecting conduits and detection cavities to extract any gas leakage within the power plant. Gas measuring devices and display devices are included in the system to identify, quantify or locate gas leakage.

Abstract: A vaulted cover for an opening in a pressure vessel comprising a vaulted center piece and an annular rim surrounding thermal insulation material of a cover flange. The rim is assembled of two coaxially arranged cylindrical sections. Expansion gaps and sealing disks are provided about pipe fittings in said vaulted cover in a manner that permits release of pressure through gaps formed by said sealing disks.

Abstract: An improved design for shielding the component parts of a gas turbine power plant from radiation in a gas transport conduit is disclosed. The radiation shield and shielded gas conduit utilize a shielding arrangement comprising a displacement body arranged centrally within the conduit and a shielding annulus surrounding the displacement body. A shielding device provides for a first annular flow path for reactor cooling gas between the displacement body and shielding annulus and a second annular flow path for reactor cooling gas between the shielding annulus and the conduit housing. The shielding device provides protection against radiation without significantly disrupting the flow of the cooling gas in the conduits.

Abstract: Disclosed is an angled gas conduit for a gas flowing under high pressure and at an elevated temperature which comprises a first conduit part and second conduit part connected at an angle forming an area of deflection for gas flowing within said conduit parts, an apertured plate arranged at an oblique angle within said conduit in the area of deflection, the apertured plate having a plurality of circular passages for directing the flow of gas in the conduit. A mounting arrangement for the apertured plate is also disclosed.

Abstract: Disclosed is a closing arrangement for large passages in a prestressed pressure vessel comprising a cover means for covering the opening of a passage in the prestressed pressure vessel, an annular structural part having an inner boundary surface surrounding the covering means at a distance and defining a space therebetween, a means for securing the annular structural part to the prestressed pressure vessel and a plurality of connecting elements disposed in the space between the annular structural part and the covering means in abutting relationship with the inner boundary surface of the annular structural part and the covering means.

Abstract: The drive for an absorber rod for a nuclear reactor has a drive piston guided in a cylinder combined with the absorber rod forming an absorber unit. In order to compensate the forces exerted by the medium of the pressure vessel on the absorber unit and tending to pressure the absorber rod axially outward, an equalizing surface is arranged in the absorber unit. The equalizing surface is exposed on one side to the medium of the pressure vessel and/or the cooling medium of the absorber rod, so that an equalizing force is acting on the absorber unit. In the event of a failure of the drive medium acting on the drive piston of the absorber unit or during fluctuations and changes of the internal pressure in the pressure vessel, the absorber unit remains in its existing position, i.e. no unintentional withdrawal of the absorber rod from the pressure vessel takes place.

Abstract: A plurality of graphite blocks forms a side reflector with an area of each block that allows a certain amount of radiation induced wear in a predefined zone facing the core of the reactor and an area separate from the wear zone for carrying the load bearing function of the side reflector. Most critical is the area of the upper range of the reactor core where radiation induced wear is greatest. The wear is taken into consideration in the design layout of the side reflector in the form of an increment to the thickness of the wall. The load bearing areas of each block provide the load bearing area for the entire side reflector. The side reflector is particularly suitable for high temperature gas-cooled reactors of the pebble bed type.

Abstract: Disclosed is a pressure vessel of a nuclear power plant comprising a generally cylindrical shaped first partial section, a cavity for housing a high temperature reactor within the first partial section, a second partial section forming the lower part of the pressure vessel, a horizontal tunnel for housing a gas turbine assembly within the second partial section and a plurality of recesses for housing components of a heat exchanger apparatus, wherein the cavity for housing the high temperature reactor is eccentrically arranged in the first partial section of the pressure vessel with respect to the cylindrical shape.

Abstract: A gas-cooled high temperature reactor is equipped with a supporting structure for the reactor core having a gas conduit passing through the support structure from a hot gas collecting space beneath the supporting structure. The supporting structure itself rests on a floor plate in a columnar arrangement. The floor plate also rests on support columns and possesses a disk-like center portion indirectly supporting the reactor core and an outer annular portion supporting a lateral thermal shield around the reactor core.

Abstract: A driving apparatus for raising and lowering an absorber rod within a nuclear reactor pressure vessel. The apparatus comprises a driving system which includes a motor-driven flexible support member that is connected to the absorber rod through both a coupling element and a connecting element, and a storage means for storing any excess length of flexible support member. Both the driving system and the storage means are detachably enclosed within a desired gaseous environment that is isolated from the interior of the pressure vessel by a screening plug having a passageway therein through which the connecting element is disposed for movement between an upper end position and a lower end position.