Abstract: A control rod for a pressurized-water nuclear reactor contains an absorber rod which is arranged in a casing tube. At least in a lower section, the absorber rod is provided with at least one recess which takes up at most a portion of the circumferential surface of this section. This reduces problems associated with an expansion in the volume of the absorber rod.

Abstract: The invention provides at least two electrochemical sensors positioned in a nuclear reactor or in a system adjacent to the nuclear reactor, wherein at least one of the at least two electrochemical sensors has a heated zirconium electrode, and the at least two electrochemical sensors produce voltages proportional to an electrochemical corrosion potential for a surface that each of the at least two electrochemical sensors are installed upon. The invention also provides an arrangement configured to accept the voltages produced by the at least two electrochemical sensors, wherein the arrangement is configured to determine an electrochemical corrosion potential of a zirconium fuel rod in the nuclear reactor based upon the voltages of the at least two electrochemical sensors.

Abstract: An end piece for a corrugated hose contains a bushing having a front region and a rear region opposite of a longitudinal direction. The rear region is located inside the hose in a mounted state of the bushing. The front region has a collar forming a groove for receiving the free end of the hose. The rear region has a plurality of flexible tongues, which have a relief direction that is oriented perpendicular to the longitudinal direction of the bushing and directed toward the outer chamber of the bushing. A portion of the flexible tongues contains a radially projecting detent protrusion for implementing an engagement active in the longitudinal direction of the bushing. A retaining sleeve, received by the bushing with precise fit and, in the mounted state of the end piece, extends in an inner chamber enclosed by the bushing, limits the radial play of the flexible tongue.

Abstract: A method for machining a sealing seat of a shut-off valve in a power generating or industrial plant. An upper valve part and the internal housing fittings are removed from the housing of the shut-off valve to thereby expose a housing opening. A clamping device with a counter-bearing is introduced through the housing opening into the connection pipe and fastened to its inner wall. A machine tool with a bearing is introduced through the housing opening and mounted with its bearing on the counter-bearing. A machining step is carried out with the machine tool on the sealing seat. Then the machine tool is detached and removed through the housing opening. The clamping device is detached from the connection pipe and removed through the housing opening. Then, the upper valve part and the internal fittings are reattached to the housing.

Abstract: A monitoring system for an inner area of a machine includes a radar source radiating or injecting radar radiation into the inner area and a radar receiver receiving radar radiation reflected in the inner area and emitting the reflected radar radiation as a received signal. A control and evaluation unit determines an actual signature from the received signal and compares the actual signature to a stored nominal signature representing a fault-free machine. An output unit outputs a fault error signal when a discrepancy between the actual signature and the nominal signature exceeds a tolerance value.

Abstract: A cyclone separator for phase separation of a fluid stream has a rotationally symmetrical housing with a hollow chamber. Feed lines feed the fluid stream into the housing substantially tangentially. At least one discharge line conducts the separated gaseous fraction. In order to ensure uniform and homogeneous flow distribution of the steam to be heated as it enters the heating phase, the hollow chamber, when viewed in the radial direction from the mid-axis, has an outflow chamber with a circular cross section and, in radial sequence, a heating chamber, an intermediate chamber, a dryer chamber and an inflow chamber. The inflow chamber is outwardly delimited by the housing. The heating chamber contains heating elements for heating the gaseous fraction. At least one fine separator and at least one associated condensate-collecting trough are arranged in the dryer chamber.

Abstract: A method and a device measure for a deformation of a fuel element of a pressurized water reactor having a plurality of control rod guide tubes. A probe displaceable in the direction of the longitudinal axis of the control rod guide tube is inserted in the interior of at least one control rod guide tube having at least one reference axis, and supported in at least one section of the control rod guide tube on the interior wall thereof, such that the orientation of the at least one reference axis is unambiguously a function of the orientation of the longitudinal axis of the control rod guide tube in the section. The orientation of the at least one reference axis in the section of the control rod guide tube is determined relative to the orientation of the or a further reference axis of the probe in a different section.

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 and an apparatus for test an annular weld at a main coolant line connected to a reactor pressure vessel in a nuclear power plant, include a self-propelled submersible vehicle which is introduced into an opened, flooded reactor pressure vessel. The submersible vehicle has at least one test device to be placed against an inner circumferential surface of the main coolant line and moved in circumferential direction of the main coolant line. The submersible vehicle is advanced into the main coolant line, which is also flooded, and is fixed in the region of the weld by radially deployable spreading or extension arms. The test device is then placed against the weld and is moved therealong in the circumferential direction.

Abstract: A method produces a welded connection between first and second components each having inner and outer sides interconnected by an end face. The first component has a ferritic basic body carrying a plating at the inside and having an end face with a buffer layer of Ni-based alloy. The second component is of austenitic material. The end faces of the components enclose a weld groove. An austenitic root, connecting the plating to the end face of the second component, is welded in the weld groove. An intermediate layer of a nickel alloy having at least 90% nickel is welded onto the root. The intermediate layer is connected to the end faces of the plating and the second component. A weld seam is then produced in the remaining weld groove using a nickel-based welding additive. A method for repairing a welded connection between first and second components is also provided.

Abstract: A nuclear installation has a reactor containment which is connected to a pressure relief line. A Venturi scrubber, which is arranged in a vessel containing a washing liquid, and a throttle device are connected in series in the pressure relief line. The novel system restrains, with particularly high reliability, fine air-transported activities or aerosols during decompression such that release thereof into the environment is practically impossible. The Venturi scrubber and the throttle device are dimensioned in such a way that, in the case of a critical drop in pressure of an air-vapor mixture flowing in the decompression line, a flow speed of said air-vapor mixture of more than 150 m/s, preferably more than 200 m/s, can be adjusted with respect to the throttle device in the Venturi scrubber.

Abstract: A method chemically decontaminates a surface of a metal component of a primary circuit of a pressurized-water reactor, the surface contains an oxide layer. In a first stage, an oxidation step, a reduction step, and a first decontamination step are performed. The component is treated in the oxidation step with an aqueous solution containing an oxidizing agent, which converts trivalent chrome present in the oxide layer into hexavalent chrome. The component is treated in the reduction step with an aqueous solution containing a reducing agent for reducing excess oxidation agent from the oxidation step. The component is treated in the first decontamination step with an aqueous solution containing a decontamination acid that forms no antisoluble deposits with metal ions in the solution. The solution is fed through an ion exchanger for removing metal ions. In a second stage, the component is treated with an aqueous solution containing an oxalic acid.

Abstract: A nuclear power plant is provided including a BWR, a reactor cooling system cooling the BWR, an HWC hydrogen injection system connected to the reactor cooling system and an alcohol injection system connected to the reactor cooling system. Methods for providing methanol and hydrogen are also provided.

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 nuclear engineering plant has a containment, whose interior chamber is subdivided by a wall into a systems chamber and an operating chamber which is accessible during normal operation. The containment ensures a particularly high operational reliability, in particular also in incident situations, in which hydrogen is released in the systems chamber. For this purpose, a number of overflow openings are provided in the partition wall, the respective overflow opening is closed by a closure element of a closure apparatus which opens automatically when a trigger condition associated with the respective overflow opening is reached. Closure apparatuses are provided which open both as a function of pressure and independently of pressure. The closure apparatus furthermore has a closure element containing a bursting film or a bursting diaphragm. The closure apparatus is configured such that it frees the overflow opening automatically when a predetermined environment-side trigger temperature is reached.

Abstract: A sealing device for a device for measuring a fill level in a fluid container, particularly in a pressure container of a nuclear facility, includes at least one thermocouple which is connected by a pressure pipe to the pressure container and a pipeline connected to the pressure pipe to an evaluation unit. The pressure pipe and the pipeline are connected to each other by a pipe screw connection including a central part having two threaded pieces. One threaded piece is connected by a screw connection to a pipe sleeve and the other threaded piece is connected by a further screw connection to the pressure pipe.

Abstract: A method and a corresponding device for the pressure relief of a nuclear power plant having an outlet for a relief flow. The relief flow is guided out of a containment into the atmosphere via a relief line provided with a filter system. The filter system has a filter chamber with a filter-chamber inlet and outlet and a sorbent filter arranged therebetween. The relief flow is guided in a high-pressure section of the relief line past the filter chamber, with the latter being heated, and the relief flow is expanded at the end of the high-pressure section and dried. In order for efficient retention of iodine-containing organic compounds, the relief flow is guided through a bed filter, guided in a superheating section past the high-pressure section of the relief line and in the process is heated, guided in this state directly thereafter through the filter chamber having the sorbent filter.

Abstract: A nuclear engineering plant has a containment, whose interior chamber is subdivided by a wall into a systems chamber and an operating chamber which is accessible during normal operation. The containment ensures a particularly high operational reliability, in particular also in incident situations, in which hydrogen is released in the systems chamber. For this purpose, a number of overflow openings are provided in the partition wall, the respective overflow opening is closed by a closure element of a closure apparatus which opens automatically when a trigger condition associated with the respective overflow opening is reached. Closure apparatuses are provided which open both as a function of pressure and independently of pressure. The closure apparatus furthermore has a closure element containing a bursting film or a bursting diaphragm. The closure apparatus is configured such that it frees the overflow opening automatically when a predetermined environment-side trigger temperature is reached.

Abstract: A device for phase separating a multi-phase fluid flow has a housing configured substantially rotationally symmetrically about a center axis and encloses a hollow space, at least one in-feed line for the fluid flow configured for inflow of the fluid flow directed substantially tangentially to an interior of the housing, and at least one outlet line for the separated gaseous portion of the fluid flow. The device heats the gaseous portion of the fluid flow, such as steam, and requires little material and space. To this end, heating elements configured for heating the gaseous portion are disposed in the hollow space in an annular chamber placed concentrically about the center axis.

Abstract: In a fuel element for a pressurized-water reactor, in addition to spacers, flow-guiding structural parts are arranged. The flow guiding parts include four outer webs which, in a plane oriented perpendicularly to the central longitudinal axis, surround a square inner region of which the center point lies on the central longitudinal axis. At their lower longitudinal side facing the flowing cooling water in the operating state, the outer webs are provided with deflection lugs pointing towards the inner region and are structurally identical, wherein mutually opposite outer webs are arranged mirror-symmetrically with respect to a center plane extending in the axial direction. Such a structural part forms, at most for a number of fuel rods which is smaller than their total number in the fuel element, cells through which a respective fuel rod is guided. The number of these cells, which are situated in a row or column, is smaller than the number of the fuel rods respectively situated in this row or column.