Abstract: A method for producing a collecting line, and a collecting line produced according to the method is provided for detecting and locating an agent discharging into the environment of the collecting line in case of leakage. Such a collecting line has a carrier pipe, the wall of which is equipped with openings that are sealed by an elastic material that is permeable for the agent. Accordingly, a hose made of the permeable elastic material, the inside diameter of which is smaller than the outside diameter of the carrier pipe, is elastically expanded by creating a pressure difference between the interior and the exterior of the hose. The carrier pipe is inserted into the radially expanded hose, and the radially expanded hose is attached to the outside surface of the carrier pipe by reducing the pressure difference.

Abstract: Fuel rods of fuel assemblies of a boiling water reactor are tested for leaks. A plurality of fuel assemblies are each arranged adjacent to one another in a cell of the upper core grid of the boiling water reactor. A hood is placed above a plurality of cells A water sample is taken from each of the cells, and the water samples from a plurality of cells forming a group are combined and tested for the presence of radioactive fission products A plurality of groups are analyzed simultaneously in a number, which number corresponds to the number of groups, of measurement channels. Where a result of a group is positive, the cells of the group are tested separately by the measurement channels. Those fuel assemblies of a cell that is found positive are tested individually outside the hood.

Abstract: A collector line for leakage monitoring and leakage location at a plant includes a carrier tube having a wall with openings formed therein, which are sealed with silicone rubber. This makes it possible to use the collector line during low ambient temperatures. A device and a method for leakage monitoring and leakage location and a pipeline having a collector line, are also provided.

Abstract: A device is provided for repairing a damaged location in an underwater region of a wall of a vessel or pool, in particular in the region of a wall of a pool of a nuclear reactor plant. The device includes a guiding system, which can be attached along a side wall at a distance therefrom and can be fixed thereto, for guiding a carriage which can be made to move in a longitudinal direction of the guiding system. Arranged on the carriage is a displaceably mounted holder for a repair support, which can be placed with an adhesive surface against the wall region containing the damaged location. With such a device, wall regions that are at a great depth and can only be accessed through narrow gaps can be repaired quickly and reliably.

Abstract: A covering element for a reactor core of a nuclear installation provides a secure and tight closure of the reactor core in an operating state and at the same time being simple and cost effective to produce. The covering element is easily disassemblable during maintenance or loading processes and provides good possibilities for intervention in the reactor core. For this purpose, the covering element has a closure head and a separate support ring. The support ring is joined form-lockingly and/or force-lockingly to the closure head.

Abstract: In a method for detecting a leak in a double pipe, a medium located in an intermediate chamber between the interior and exterior pipe is moved toward a first end of the pipe, whereupon the medium flows in from the second end. On the first end the medium is examined for any leakage of a characteristic material, upon the detection of which a leakage signal is generated and a location of the leakage is calculated based on the transport time of the characteristic material from the leakage to the first end and on the mass flow of the medium. A corresponding device contains a conveyor unit for moving the medium through the intermediate chamber. A material sensor is disposed at the first end for examining the medium for the characteristic material. A control and analysis unit is provided for generating a leakage signal and calculating the location of the leakage.

Abstract: A method for decontaminating nuclear plant surfaces, which have been contaminated with alpha emitters, is carried out subsequently to a decontamination process which is aimed at the removal of oxide layers. The surfaces are treated with an aqueous solution which contains a cationic or zwitterionic surfactant and oxalic acid. At least a part of the solution, after having acted on a surface, is conducted across an ion exchanger.

Abstract: A method and a device for detecting a pulse-type mechanical effect at a system component, include continuously recording an operating noise in the system component with a sensor disposed at the system component and converting the operating noise with the sensor into a measured signal subjected to a mathematical transformation. A sliding mean is calculated by determining quantiles from determined transformations and an evaluation function, which displays an application of the pulse-type mechanical effect on the system component, is derived from the sliding mean.

Abstract: A containment vessel of a boiling-water nuclear power plant and a method of operating a condenser in a nuclear power plant, include a drain pipe which connects a top region of the containment vessel to a condensing chamber disposed in the containment vessel. The drain pipe draws off noncondensible gases from the surroundings of a building condenser in the containment vessel and thus maintains reliability of performance of the building condenser. The noncondensible gases flow automatically into the condensing chamber through the drain pipe. As a result, the building condenser may have a simple and cost-effective structure.

Abstract: A method enables dismantling of a control element of a boiling water reactor. Two control element leaves that are disposed opposite one another are separated by means of a roll-cutting method from the other two control element leaves, respectively along an intersection line extending in the longitudinal direction thereof and in the vicinity of the longitudinal center axis.

Abstract: A feeding system for an absorber liquid containing a neutron poison, in particular for a quick shut-down of a nuclear reactor, has a storage container for the absorber liquid and is configured for high operational reliability with simple construction. In particular, a chemical decomposition of the absorber liquid or corrosion of the container wall of the storage container is to be excluded. For this purpose, the storage container is connected to a pressure container via an overflow line, wherein the pressure container is filled with a motive fluid.

Abstract: The core of a pressurized water reactor is assembled in such a way that if the fuel elements on the edge of the core are bent, these fuel elements are oriented such that the bending of the fuel elements points outwards in a convex manner. When the reactor is in operation, forces arise which increase the size of small gaps between the fuel elements at the expense of greater gaps and counteract the bending effect of the fuel elements.

Abstract: A method to remove deposits containing magnetite and copper from a container, particularly from a steam generator of a nuclear power plant. In a first step, the container is treated using an alkaline cleaning solution containing a complexing agent forming a soluble complex with iron ions, a reducing agent, and an alkalizing agent. In a second step a further complexing agent forming a more stable complex with iron III ions than the complexing agent used in the first step and an oxidant are added to the cleaning solution of the first step present in the container.

Abstract: A method for treating or preparing a fuel rod cladding tube in such a way that an influence of iron oxide deposits on its surface can be studied and assessed precisely under virtually operational conditions with as little risk as possible, includes at least partially coating the fuel rod cladding tube with an iron oxide layer by immersing it in an aqueous electrolyte medium which contains iron oxide particles. The iron oxide particles are produced by anodic oxidation of an iron-containing working electrode. A test body and a device for pretreating a fuel rod cladding tube with an electrochemical three-electrode configuration, are also provided.

Abstract: A collecting line for leakage monitoring in an installation is permeable to a substance to be monitored in at least one subarea extending along the longitudinal direction. The collecting line is formed of at least two subsections that are spaced from a first end of the collecting line. The distance between the second subsection and the first end is larger than the distance between the first subsection and the first end. The permeability to the substance to be monitored is higher in the first subsection than in the second subsection. A device having the collecting line is also provided.

Abstract: An apparatus for measuring the filling level in a liquid vessel, in particular in a reactor vessel of a nuclear-engineering plant, with a plurality of elongate, spaced-apart measurement tubes. Each measurement tube has a number of thermocouples which are distributed in the longitudinal direction. A thermocouple, which acts as a primary signal transmitter, is heated by a heating element and is arranged on a first measurement tube, has assigned to it on the signal side an unheated thermocouple, which acts as a reference signal transmitter and is arranged on a measurement tube which is different from the first measurement tube.

Abstract: A nuclear-engineering installation has a pressurized-water reactor and a degasification system for reactor coolant. The degasification system has a degasification column which is coupled to the primary cooling circuit of the pressurized water reactor and further includes a coolant evaporator with a first heat exchanger and a stripping vapor condenser with a second heat exchanger, wherein a partial flow of the reactor coolant flows through the heat exchanger of the coolant evaporator on the secondary side, and wherein the heat exchanger of the stripping vapor condenser is connected, on the primary side, in a vapor and gas outlet line which is connected to the degasifier column.

Abstract: An apparatus for loading and unloading a core of a pressurized water reactor exerts a force acting transversely to an axial direction of a fuel assembly against an upper region of a fuel assembly adjacent a fuel assembly unloading or loading position of the core. The apparatus is an immersion vehicle being freely maneuverable under water and on which an extendable carrier arm is disposed and at least indirectly positioned against the fuel assembly.

Abstract: A containment of a nuclear power plant has a pressure chamber, a condensation chamber, and a substantially vertically running condensation tube. The upper end of the tube is connected to the pressure chamber and the lower end of the tube is immersed in a cooling liquid in the condensation chamber. The lower end of the condensation tube has an elbow and an outlet nozzle. The elbow has an elbow angle which is such that the lower end of the elbow is immersed obliquely in the cooling liquid in the condensation chamber, and the outlet nozzle has an outlet opening which is substantially shielded with respect to the base of the condensation chamber. This renders it possible to significantly reduce the pressure loads on the base and the walls of the condensation chamber in the event of an emergency.

Abstract: A fuel pellet for a nuclear reactor contains a matrix made of an oxidic nuclear fuel and a metallic phase that is deposited within or between the fuel grains and is preferably aligned in a radial direction relative to the coating surface of the pellet. A method for producing the fuel pellet includes forming slugs containing a precursor of the metallic phase, which has a melting point lying below the sintering temperature and can be transformed into the metallic phase in sintering conditions, in addition to the oxidic nuclear fuel and other optional additives. The slugs are then sintered. The slugs are heated up so quickly that at least one portion of the precursor is liquefied before being completely transformed into the metallic phase.