Abstract

A device for measuring bending of extended vertically directed channels, including nuclear reactor fuel channels of the high-power channel-type reactor (HPCR). The device comprises a flexible hollow carrier rod having at least one fibre-optic sensor equipped with a core closed by a sealed tubular casing. The upper part of the core comprises a mounting sleeve with a central cylindrical cavity. The lower part of the core is comprises a central cylindrical rod. Longitudinal sector cuts are made on the rod of the core, in which ferrules with longitudinal through channels are fixed, and a gravity pendulum is placed under the lower end of the rod. Through the through channels of the ferrules, fiber-optic lines are drawn, connecting each fibre-optic sensor with a tunable laser and a photoreceiver connected to a computer. The cavity of the sealed tubular casing of the fibre-optic sensor is filled with an inert gas.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations

Abstract

Method of measuring bending of a nuclear reactor fuel channel. A fiber-optic sensor comprises a gravity pendulum that is at the lower end of the fibre-optic sensor; a flexible hollow carrier rod with the fibre-optic sensor is passed along the central tube of a fuel assembly and detecting a gas gap with a photoreceiver, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed central tube of the fuel assembly. Profilograms of the variations of the gas gap for each fibre-optic line of each fibre-optic sensor are recorded; and the magnitude and direction of bending of the central tube of the fuel assembly from the vertical axis are calculated, according to which the presence and magnitude of bending of the nuclear reactor fuel channel are determined.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations

Abstract

A method for measuring bending of extended vertically directed channels. A fibre-optic sensor having a gravity pendulum fixed at the end of a flexible hollow carrier rod is placed inside the extended vertically directed channel. A light signal is supplied via fibre-optic lines connected to the sensor to record light signals. The flexible hollow carrier rod with the fibre-optic sensor is placed along the channel and detects interference in a gas gap with a photoreceiver, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed channel. Profilograms of the variations of the gas gap for each fibre-optic line are recorded; and the magnitude and direction of bending of the channel from the vertical axis are calculated to simplify measurements of bending of a vertically directed channel while maintaining measurement accuracy.

IPC Classes  ?

• G01B 11/24 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures
• G01B 9/02015 - Interferometers characterised by the beam path configuration

Abstract

A robotic monitoring, detection and fire extinction control system comprising a pumping station, a fire main and at least two robotized fire extinguishing units connected to the fire main comprising a fire monitor with drives for vertical and horizontal aiming and a head with a drive for adjusting the spray angle of the jet. A butterfly valve with a drive is mounted to an inlet of the fire monitor, and a pressure sensor and a portable control console are mounted to an outlet of the fire monitor. The pressure sensor and portable control console are connected to a switching unit at the inlet and, via a network controller, to a control device at the outlet. A fire detection and video surveillance device is connected via a receiving and control device to fire alarms. A foam generating unit is connected to the robotized fire extinguishing units by a foam conduit.

IPC Classes  ?

• A62C 3/02 - Fire prevention, containment or extinguishing specially adapted for particular objects or places for area conflagrations, e.g. forest fires, subterranean fires
• A62C 5/02 - Making of fire-extinguishing materials immediately before use of foam
• A62C 27/00 - Fire-fighting land vehicles
• A62C 31/12 - Nozzles specially adapted for fire-extinguishing for delivering foam or atomized foam
• A62C 35/68 - Details, e.g. of pipes or valve systems
• A62C 37/38 - Control of fire-fighting equipment an actuating signal being generated by a sensor separate from an outlet device by both sensor and actuator, e.g. valve, being in the danger zone

Abstract

A system for confining and cooling melt from the core of a nuclear reactor comprises a guide device, a cantilever truss, a filler for receiving and distributing melt. The filler being disposed in a housing having water supply valves mounted around its perimeter and having a flange with a thermal shield mounted thereon. A drum is mounted on the flange and comprises reinforcing ribs mounted around its perimeter on the inner side. The reinforcing ribs bear against a cover and a bottom. The drum comprises tensioning elements connecting the drum, via a support flange, to the flange of the housing, and spacing elements providing an adjustment gap between the drum and the flange of the housing. The drum comprises nozzles equipped with heat reflectors, cooling ribs, and water supply valves mounted for increasing the reliability of the system for confining and cooling melt from the core of a nuclear reactor.

IPC Classes  ?

• G21C 9/016 - Core catchers
• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

A water supply valve comprises an actuating sleeve inserted in an intermediate sleeve and bearing on said intermediate sleeve by means of flanged stops, an actuating rod with a piston, said actuating rod being mounted inside the actuating sleeve and the intermediate sleeve so that the actuating rod bears, via the piston, on a thermomechanical element which bears, via a pressure mechanism, on a protective membrane fastened in the end of the actuating sleeve, an actuating spring mounted on the actuating rod so that one end of the spring bears on the piston and the other end bears on the flanged stops of the actuating sleeve, a rolling bearing mounted on the end of the actuating rod which projects from the actuating sleeve, a flanged cylinder in which is inserted a flanged sleeve with a rod-type sleeve mounted therein, the latter receiving a stem with a thread and with a control valve, said stem being rollably mounted, and a thrust sleeve in which are mounted a flanged thrust rod and a working spring, one end of which bears on the flanges of the thrust rod and the other end of which bears on the thrust sleeve, wherein mounted between the control valve and the thrust rod is a ball bearing.

IPC Classes  ?

• F16K 17/38 - Safety valvesEqualising valves actuated in consequence of extraneous circumstances, e.g. shock, change of position of excessive temperature

Abstract

A system for confining and cooling melt from the core of a nuclear reactor comprises a guide device, a cantilever truss, a filler for receiving and distributing melt. The filler being disposed in a housing having water supply valves mounted around its perimeter and having a flange with a thermal shield mounted thereon. A drum is mounted on the flange and comprises reinforcing ribs mounted bearing against a cover and a bottom. The drum comprises tensioning elements connecting the drum, via a support flange, to the flange of the housing, and spacing elements. The drum comprises nozzles having water supply valves mounted therein with sealed covers, and hydraulic dampers connected to external sources of water and to the water supply valves by feed pipes, pressure pipes, compensating pipes and equalizing pipes, for increasing the reliability of the system for confining and cooling melt from the core of a nuclear reactor.

IPC Classes  ?

• G21C 9/016 - Core catchers
• G21C 13/10 - Means for preventing contamination in event of leakage

Abstract

Methods for cleaning a NPP steam generator tube bundle. The methods characterized in that a hydrodynamic manipulator connected to a hoist is inserted into a vertical corridor inside a heat exchanger. The methods include taking preliminary measurements of the dose rate inside the steam generator, measuring eddy current signals and analyzing the signals received to assess the condition of the walls of heat exchange tubes and deposit thickness. The methods further include determining the coordinates of a cleaning sector and calculating cleaning time and modes, ejecting a high-pressure jet of water using at least one nozzle configured to rotate around the swiveling axis, and moving the hydrodynamic manipulator according to the coordinates of the cleaning sector with the water jet set at a feed pressure of 1000 to 1500 bar and a flow rate of 100 to 150 l/min and a simultaneous video monitoring of the cleaning zone.

IPC Classes  ?

• F28G 1/16 - Non-rotary, e.g. reciprocated, appliances using jets of fluid for removing debris

Abstract

Systems and arrangements for detecting leans and repairing damaged lining of NPP spent fuel pools filled with water. The arrangements and systems include devices that are not submerged to the spent fuel pool, including welding equipment, and devices submerged to the spent fuel pool, including a submersible repair platform for the working mechanism installation. The working mechanism includes a device for cleaning of weld seams and the surface of the spent fuel pool, and a wire cutting device, comprising a container for collection of cuttings and a pump for particulate removal. The leak sealing device is arranged in the form of a small-scale welding assembly connected to the welding equipment, and the submersible repair platform is equipped with means for its attachment to the surface of the spent fuel pool. The arrangement for repairing the lining of a spent fuel pool includes a submersible repair robot having a working unit.

IPC Classes  ?

• B23K 9/00 - Arc welding or cutting
• B23K 37/02 - Carriages for supporting the welding or cutting element

Abstract

The invention relates to cleaning of tube bundle of NPP steam generator. The device for cleaning heat exchange tubes of NPP steam generator comprising a manipulator, which is installed to be moved and fixed in a vertical corridor between bundles of heat exchange tubes; a nozzle that is installed on the manipulator ad is in the form of a head of injectors connected to a pipeline for supplying high-pressure water jets; and means for remote control and video monitoring, wherein the manipulator is equipped with a body, which is installed on a guiding mounting frame and is connected to a base; a drive for main rotational movement located on the body; a post which is connected to the body and is in the form of a hollow column; a drive for auxiliary movement which is fixed on the post, an elbow which is connected to the post and is in the form of a tube having a gear rack, and an elbow of actuating units and a coordinate head. The technical result is a shorter cleaning time and more reliable removal of deposits.

IPC Classes  ?

• F28G 3/16 - Rotary appliances using jets of fluid for removing debris
• F28G 15/00 - CLEANING OF INTERNAL OR EXTERNAL SURFACES OF HEAT-EXCHANGE OR HEAT-TRANSFER CONDUITS, e.g. WATER TUBES OF BOILERS Details

Abstract

Methods for diagnostics of electrically driven equipment and monitoring of vibrations in rotating equipment at nuclear power plants. The methods include measuring and recording of diagnostic signals, dividing the recordings of a reference signal and the signal from the equipment under inspection into segments, converting each segment of the recordings of the reference and inspection signal into a spectrum which represents the distribution of amplitudes across frequencies, sampling amplitudes of the diagnostic signal spectra from the inspected and fault-free equipment at the frequencies where deviations appear between the inspection and reference signals, calculating absolute amplitude difference in the spectra, ranking of the absolute differences and summarizing the ranks. Comparing summarized ranks with the critical value to establish whether the rotating equipment is in excess of the prescribed vibration values and to establish the presence of fault if the sum of the resultant ranks exceeds the critical value.

IPC Classes  ?

• G01H 1/00 - Measuring vibrations in solids by using direct conduction to the detector
• G01M 13/045 - Acoustic or vibration analysis

Abstract

A method for measuring vibration acceleration in three mutually orthogonal planes via vibration sensors. Vibration accelerations are measured at the monitoring points on an operational and knowingly fault-free diesel generator, and then vibration accelerations are measured at the monitoring points of a diesel generator in the course of its operation with prescribed intervals. Temperature and intensity of an ultrasonic signal are additionally measured at the same monitoring points, and the root mean square values of the ultrasonic signal intensity, temperature and vibration acceleration are determined. The measured vibration acceleration values are used to calculate the root mean square values of vibration velocity and vibratory displacement, the distances between clusters of preceding measurements are determined, and a conclusion on the operating state of the diesel generator is made. The method promotes timely detection of any operating defects through periodic measurements and comparison of calculations.

IPC Classes  ?

• G01M 15/12 - Testing internal-combustion engines by monitoring vibrations

Abstract

Systems for ensuring safety of nuclear power plants (NPPs), and can be used in severe accidents resulting in destruction of the reactor pressure vessel and containment. The systems enhance reliability of the corium localizing and cooling system of a nuclear reactor. The technical result is achieved due to prevention of the corium localizing and cooling system destruction in the junction area between the vessel and the cantilever truss by use of a membrane with bandage plates installed on the drum within the system.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to a self-cleaning liquid purification system and is designed for the use in sump tank filters in nuclear power plants, as well as in any submersible filters used in any sectors of the economy. A self-cleaning liquid purification system comprises a filtration unit with filtering elements, a clean liquid discharge pipe, and an aerator. The aerator is designed as an intake device located on the liquid-gas boundary in a source of liquid to be purified, the aerator is capable of forming a liquid-gas mixture when it enters the intake device. The aerator is connected with a vertical downcomer to an accumulation chamber that is connected to the filtration unit by a hydraulic lock that is designed to be capable of pulse feed of liquid-gas mixture. The technical result is improved operation reliability of the liquid purification system through ensuring its capability of self-cleaning in the passive mode.

IPC Classes  ?

• G21D 1/02 - Arrangements of auxiliary equipment
• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

The invention relates to the field of chemical engineering, and more particularly to a device for combusting ammonia, which can be used in heating devices for producing heat and in devices for decomposing ammonia into a nitrogen-hydrogen mixture. A device for combusting ammonia comprises a cylindrical combustion chamber, a device for supplying an air-ammonia mixture, which includes at least one main supply channel having a tangential vortex generator mounted at the end thereof, a spark igniter mounted in the combustion chamber, and a channel for suppling a support fuel that has heightened combustibility. Further provided is a cylindrical housing, inside which the cylindrical combustion chamber is arranged in coaxial alignment and so that an annular additional channel for supplying and heating the air-ammonia mixture is formed between the housing and the combustion chamber by the inlet of the main supply channel and by the tangential vortex generator. The cylindrical side surfaces of the housing and the combustion chamber are provided with at least one through-opening for the spark igniter. Flame sensors, a device for supplying secondary air, and a flame stabilizer are provided, and the combustion chamber is designed to allow cooling and has a catalytic unit mounted at the outlet thereof. The technical result is an improvement in the environmental parameters of the burner, as well as the operating reliability and safety thereof.

IPC Classes  ?

• F23C 1/00 - Combustion apparatus specially adapted for combustion of two or more kinds of fuel simultaneously or alternately, at least one kind of fuel being either a fluid fuel or a solid fuel suspended in air
• F23C 13/08 - Apparatus in which combustion takes place in the presence of catalytic material characterised by the catalytic material
• F23L 9/00 - Passages or apertures for delivering secondary air for completing combustion of fuel
• F23N 5/10 - Systems for controlling combustion using devices responsive to thermal changes or to thermal expansion of a medium using thermocouples

Abstract

meltmelt for 10 hours, exhibits a loss in mass of not more than 2%.

IPC Classes  ?

• G21C 3/64 - Ceramic dispersion fuel, e.g. cermet
• C04B 35/565 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides based on carbides based on silicon carbide

Abstract

The group of inventions relates to nuclear fuel material, and more particularly to a high-temperature dense composite nuclear fuel material and a method for producing same. The high-temperature dense composite nuclear fuel material comprises a radiation-inert ceramic matrix in which particles of nuclear fuel are distributed. The matrix is formed from a powder material based on silicon carbide. The particles of nuclear fuel are particles of an oxygen-free nuclear fuel. The method for producing a high-temperature dense composite nuclear fuel material includes preparing a mixture of the nuclear fuel particles and the powder for the formation of a radiation-inert ceramic matrix, compression moulding said mixture and sintering the moulded mixture. The moulded mixture is sintered using the hot pressing method. The group of inventions makes it possible to produce a high-temperature dense composite nuclear fuel material which, after vacuum annealing at 0.63Tmelt for 10 hours, exhibits a loss in mass of not more than 2%.

IPC Classes  ?

• G21C 3/64 - Ceramic dispersion fuel, e.g. cermet

Abstract

The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of the nuclear reactor, increase of heat removal efficiency from corium of the nuclear reactor. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of the nuclear reactor, increase of heat removal efficiency from corium of the nuclear reactor. The technical result is achieved by using upper heat insulation in the corium localizing and cooling system of the nuclear reactor, installed in the area between the reactor pressure vessel and cantilever truss, and lower thermal protection installed inside the reactor pressure vessel on the filler upper cassette.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of a nuclear reactor, increase of heat removal efficiency from corium of a nuclear reactor. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of a nuclear reactor, increase of heat removal efficiency from corium of a nuclear reactor. The technical result is achieved through the use of the membrane and thermal shield installed in the area between the multilayer casing and the cantilever truss in the corium localizing and cooling system of a nuclear reactor.

IPC Classes  ?

• G21C 9/016 - Core catchers
• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

The invention relates to the production of carbon products, and more particularly to a technique for treating carbon products during calcination, and can be used in different technical fields for manufacturing electrodes, crucibles and heaters, as well as materials for nuclear engineering such as, for example, uranium-graphite fuel elements. In a method of producing carbon graphite products that includes placing workpieces in a container with a packing and calcining the workpieces in an air atmosphere, carbamide is used as the container packing in an amount of 5-10 wt% of the workpieces. The container is placed in a closed receptacle with a restricted air supply, which is filled with a carbon packing also containing carbamide in an amount of 5-10 wt% of the packing. The aim of the invention and the technical result achieved using the invention is that of simplifying the calcination process and improving the quality of carbon graphite products, particularly products with small dimensions, by preventing oxidation of said products and coking of the packing.

IPC Classes  ?

• C01B 32/21 - After-treatment
• C04B 35/532 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides based on carbon, e.g. graphite obtained from carbonaceous particles with or without other non-organic components containing a carbonisable binder

Abstract

The invention relates to the production of carbon products, and more particularly to a technique for treating carbon products during calcination, and can be used in different technical fields for manufacturing electrodes, crucibles and heaters, as well as materials for nuclear engineering such as, for example, uranium-graphite fuel elements. In a method of producing carbon graphite products that includes placing workpieces in a container with a packing and calcining the workpieces in an air atmosphere, carbamide is used as the container packing in an amount of 5-10 wt% of the workpieces. The container is placed in a closed receptacle with a restricted air supply, which is filled with a carbon packing also containing carbamide in an amount of 5-10 wt% of the packing. The aim of the invention and the technical result achieved using the invention is that of simplifying the calcination process and improving the quality of carbon graphite products, particularly products with small dimensions, by preventing oxidation of said products and coking of the packing.

IPC Classes  ?

• C01B 32/21 - After-treatment
• C04B 35/532 - Shaped ceramic products characterised by their compositionCeramic compositionsProcessing powders of inorganic compounds preparatory to the manufacturing of ceramic products based on non-oxides based on carbon, e.g. graphite obtained from carbonaceous particles with or without other non-organic components containing a carbonisable binder

Abstract

The invention relates to measuring technology, and more particularly to equipment for measuring bending of elongate vertically oriented channels, inter alia fuel channels in a high-power channel-type nuclear reactor (RBMK). The technical result is a device that can be manufactured more easily, without detriment to its accuracy in measuring bending of a channel, inter alia a nuclear reactor fuel channel. The device comprises a flexible hollow carrier rod equipped with at least one fibre-optic sensor having a core enclosed in a hermetic tubular casing. The upper part of said core is configured in the form of a positioning sleeve having a central cylindrical cavity. The lower part of the core is configured in the form of a central cylindrical stem. Configured on the central stem of the core are longitudinal sector-shaped cut-outs in which are fastened ferrules with longitudinal through-channels, and disposed below the lower end of the central stem of the core is a gravity pendulum. Passing through the through-channels of the ferrules are fibre-optic lines that connect each fibre-optic sensor to a tunable laser and a photoreceiver that are connected to a computer. The cavity of the hermetic tubular casing of the fibre-optic sensor is filled with an inert gas.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/24 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures

Abstract

The invention relates to measuring technology and can be used in the implementation of a method of measuring bending of elongate vertically oriented channels. A fibre-optic sensor fastened to the end of a flexible hollow carrier rod is placed inside a channel. A light signal is fed along fibre-optic lines connected to the sensor, and reflected light signals are recorded. The fibre-optic sensor is equipped with a gravity pendulum. The flexible hollow carrier rod with the fibre-optic sensor is passed along the channel and a photoreceiver and a computer are used to register the shift of an interference pattern of a reflected light signal in a gas gap between the upper end face of the gravity pendulum and the lower end face of fibre-optic lines connected to the photoreceiver and fastened to the sensor, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed channel. On the basis of the registered shifts, profilograms of the variations of the gas gap are recorded for each fibre-optic line, and on the basis of the obtained gas gap profilograms, the magnitude and direction of bending of the channel from the vertical axis are calculated, thereby simplifying the process of measuring bending of a vertically oriented channel while at the same time maintaining measuring accuracy.

IPC Classes  ?

• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations
• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/245 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using a plurality of fixed, simultaneously operating transducers

Abstract

Claimed is a method of measuring bending of a nuclear reactor fuel channel. The method includes equipping a fibre-optic sensor with a gravity pendulum that is suspended for angular motion at the lower end of the fibre-optic sensor; passing a flexible hollow carrier rod with the fibre-optic sensor along the central tube of a fuel assembly and using a photoreceiver and a computer to register the shift of an interference pattern of a reflected light signal in a gas gap between the upper end face of the gravity pendulum and the lower end face of fibre-optic lines connected to the photoreceiver and fastened to the sensor, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed central tube of the fuel assembly; recording, on the basis of the registered shifts of the interference pattern of the reflected light signal, profilograms of the variations of the gas gap for each fibre-optic line of each fibre-optic sensor; and calculating, on the basis of the obtained gas gap profilograms, the magnitude and direction of bending of the central tube of the fuel assembly from the vertical axis, according to which the presence and magnitude of bending of the nuclear reactor fuel channel are determined.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/245 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using a plurality of fixed, simultaneously operating transducers
• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations

Abstract

The invention relates to measuring technology and can be used in the implementation of a method of measuring bending of elongate vertically oriented channels. A fibre-optic sensor fastened to the end of a flexible hollow carrier rod is placed inside a channel. A light signal is fed along fibre-optic lines connected to the sensor, and reflected light signals are recorded. The fibre-optic sensor is equipped with a gravity pendulum. The flexible hollow carrier rod with the fibre-optic sensor is passed along the channel and a photoreceiver and a computer are used to register the shift of an interference pattern of a reflected light signal in a gas gap between the upper end face of the gravity pendulum and the lower end face of fibre-optic lines connected to the photoreceiver and fastened to the sensor, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed channel. On the basis of the registered shifts, profilograms of the variations of the gas gap are recorded for each fibre-optic line, and on the basis of the obtained gas gap profilograms, the magnitude and direction of bending of the channel from the vertical axis are calculated, thereby simplifying the process of measuring bending of a vertically oriented channel while at the same time maintaining measuring accuracy.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/245 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using a plurality of fixed, simultaneously operating transducers
• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations

Abstract

Claimed is a method of measuring bending of a nuclear reactor fuel channel. The method includes equipping a fibre-optic sensor with a gravity pendulum that is suspended for angular motion at the lower end of the fibre-optic sensor; passing a flexible hollow carrier rod with the fibre-optic sensor along the central tube of a fuel assembly and using a photoreceiver and a computer to register the shift of an interference pattern of a reflected light signal in a gas gap between the upper end face of the gravity pendulum and the lower end face of fibre-optic lines connected to the photoreceiver and fastened to the sensor, said gas gap varying during the passage of the fibre-optic sensor as a result of the angular motion of the gravity pendulum away from the axis of the bowed central tube of the fuel assembly; recording, on the basis of the registered shifts of the interference pattern of the reflected light signal, profilograms of the variations of the gas gap for each fibre-optic line of each fibre-optic sensor; and calculating, on the basis of the obtained gas gap profilograms, the magnitude and direction of bending of the central tube of the fuel assembly from the vertical axis, according to which the presence and magnitude of bending of the nuclear reactor fuel channel are determined.

IPC Classes  ?

• G21C 17/017 - Inspection or maintenance of pipe-lines or tubes in nuclear installations
• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/245 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures using a plurality of fixed, simultaneously operating transducers

Abstract

The invention relates to measuring technology, and more particularly to equipment for measuring bending of elongate vertically oriented channels, inter alia fuel channels in a high-power channel-type nuclear reactor (RBMK). The technical result is a device that can be manufactured more easily, without detriment to its accuracy in measuring bending of a channel, inter alia a nuclear reactor fuel channel. The device comprises a flexible hollow carrier rod equipped with at least one fibre-optic sensor having a core enclosed in a hermetic tubular casing. The upper part of said core is configured in the form of a positioning sleeve having a central cylindrical cavity. The lower part of the core is configured in the form of a central cylindrical stem. Configured on the central stem of the core are longitudinal sector-shaped cut-outs in which are fastened ferrules with longitudinal through-channels, and disposed below the lower end of the central stem of the core is a gravity pendulum. Passing through the through-channels of the ferrules are fibre-optic lines that connect each fibre-optic sensor to a tunable laser and a photoreceiver that are connected to a computer. The cavity of the hermetic tubular casing of the fibre-optic sensor is filled with an inert gas.

IPC Classes  ?

• G01B 11/16 - Measuring arrangements characterised by the use of optical techniques for measuring the deformation in a solid, e.g. optical strain gauge
• G01B 11/24 - Measuring arrangements characterised by the use of optical techniques for measuring contours or curvatures

Abstract

A robotic monitoring, detection and fire extinction control system comprises a pumping station, a fire main and at least two robotized fire extinguishing units connected to the fire main and comprising a nozzle with drives for vertical and horizontal aiming and a head with a drive for adjusting the spray angle of the jet. Mounted at an inlet upstream of the nozzle is a butterfly valve with a drive, and mounted at the outlet of the nozzle, upstream of the head, are a pressure sensor and a portable control console that are connected to a switching unit at the inlet and, via a network controller, to a control device at the outlet. Mounted on the nozzle is a fire detection and video surveillance device that is connected to a signal processing device that is connected to a video monitor device and to a process control system that are connected to a control device that is connected via a fire alarm control device to fire alarms. A foam generating unit is connected to the robotized fire extinguishing units by a foam conduit; additional reserve pipes, connected to the robotized fire extinguishing units, are provided for supplying water and compressed air foam; and an additional controllable butterfly valve, mounted on the foam conduit, is provided and has a drive connected to the switching unit. The head is designed to be capable of supplying water and compressed air foam at a controlled concentration and rate.

IPC Classes  ?

• A62C 37/00 - Control of fire-fighting equipment
• A62C 3/00 - Fire prevention, containment or extinguishing specially adapted for particular objects or places
• A62C 35/58 - Pipe-line systems
• A62C 99/00 - Subject matter not provided for in other groups of this subclass

Abstract

A robotic monitoring, detection and fire extinction control system comprises a pumping station, a fire main and at least two robotized fire extinguishing units connected to the fire main and comprising a nozzle with drives for vertical and horizontal aiming and a head with a drive for adjusting the spray angle of the jet. Mounted at an inlet upstream of the nozzle is a butterfly valve with a drive, and mounted at the outlet of the nozzle, upstream of the head, are a pressure sensor and a portable control console that are connected to a switching unit at the inlet and, via a network controller, to a control device at the outlet. Mounted on the nozzle is a fire detection and video surveillance device that is connected to a signal processing device that is connected to a video monitor device and to a process control system that are connected to a control device that is connected via a fire alarm control device to fire alarms. A foam generating unit is connected to the robotized fire extinguishing units by a foam conduit; additional reserve pipes, connected to the robotized fire extinguishing units, are provided for supplying water and compressed air foam; and an additional controllable butterfly valve, mounted on the foam conduit, is provided and has a drive connected to the switching unit. The head is designed to be capable of supplying water and compressed air foam at a controlled concentration and rate.

IPC Classes  ?

• A62C 3/00 - Fire prevention, containment or extinguishing specially adapted for particular objects or places
• A62C 99/00 - Subject matter not provided for in other groups of this subclass
• A62C 35/58 - Pipe-line systems
• A62C 37/00 - Control of fire-fighting equipment

Abstract

The present invention relates to the field of nuclear power engineering, and more particularly to the field of neutron flux monitoring to enable the monitoring, control and protection of pressure vessel reactors. The invention can be used for correcting errors in the power readings of a nuclear reactor and of a neutron flux monitoring apparatus on the basis of readings from self-powered detectors in an in-core monitoring system. The proposed invention solves the problem of determining with a high degree of accuracy a corrected reactor power value based on the correction of the power of a neutron flux monitoring apparatus according to readings from ex-core neutron flux sensors, taking into account their dependence on the shape of the energy distribution in the core, obtained from in-core detectors in the in-core monitoring system. The technical result of the present invention consists in making it possible to promptly and accurately determine the correction of errors in the power readings of a nuclear reactor in any of its operating modes and thus to provide for safe and reliable operation of the nuclear reactor.

IPC Classes  ?

• G21C 17/00 - MonitoringTesting
• G01T 3/00 - Measuring neutron radiation

Abstract

The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The goal of the invention is to eliminate the guide assembly failure due to the concentration of impact load in the conical part of the guide assembly and, therefore, the instantaneous penetration of the core, fragments of the reactor vessel internals and the reactor vessel head into the core catcher. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The goal of the invention is to eliminate the guide assembly failure due to the concentration of impact load in the conical part of the guide assembly and, therefore, the instantaneous penetration of the core, fragments of the reactor vessel internals and the reactor vessel head into the core catcher. In accordance with the invention, the guide assembly of the corium localizing and cooling system installed under the reactor pressure vessel and resting on the cantilever truss apart from the load-bearing frame contains the thermal elements that in the aggregate allows providing guaranteed entry of core, debris of the internals and the head of the reactor pressure vessel into the corium trap by excluding melt-through of the walls of conical and cylindrical parts and by redistributing the corium jet streams.

IPC Classes  ?

• G21C 13/10 - Means for preventing contamination in event of leakage
• G21C 9/016 - Core catchers

Abstract

The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The goal of the invention is to eliminate the guide assembly failure due to the concentration of impact load in the conical part of the guide assembly and, therefore, the instantaneous penetration of the core, fragments of the reactor vessel internals and the reactor vessel head into the core catcher. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The goal of the invention is to eliminate the guide assembly failure due to the concentration of impact load in the conical part of the guide assembly and, therefore, the instantaneous penetration of the core, fragments of the reactor vessel internals and the reactor vessel head into the core catcher. According to the claimed invention, the guide assembly of the nuclear reactor corium localizing and cooling system installed under the reactor vessel and supported on the cantilever truss contains a cylindrical part, a conical part with an opening made in it, with their walls covered with heat-resistant and fusible material and divided into sectors by bearing ribs arranged radially relative to the opening, and a bearing frame consisting of the outer upper bearing ring, the outer lower bearing ring, the inner bearing shell, the outer upper bearing shell, the middle bearing shell divided into sectors by bearing ribs, the outer lower bearing shell, support ribs, base, upper inclined plate connecting the conical head, bearing ribs and the middle bearing shell, lower inclined plate connecting the conical head, bearing ribs, the middle bearing shell and the outer upper bearing shell. The invention is applicable to the corium localizing and cooling systems of a nuclear reactor designed for localization of severe beyond design-basis accidents, in particular, to the devices for directing corium of a nuclear reactor to the corium trap. The technical result of the claimed invention is to increase the efficiency of localization and cooling of the nuclear reactor core melt. The goal of the invention is to eliminate the guide assembly failure due to the concentration of impact load in the conical part of the guide assembly and, therefore, the instantaneous penetration of the core, fragments of the reactor vessel internals and the reactor vessel head into the core catcher. According to the claimed invention, the guide assembly of the nuclear reactor corium localizing and cooling system installed under the reactor vessel and supported on the cantilever truss contains a cylindrical part, a conical part with an opening made in it, with their walls covered with heat-resistant and fusible material and divided into sectors by bearing ribs arranged radially relative to the opening, and a bearing frame consisting of the outer upper bearing ring, the outer lower bearing ring, the inner bearing shell, the outer upper bearing shell, the middle bearing shell divided into sectors by bearing ribs, the outer lower bearing shell, support ribs, base, upper inclined plate connecting the conical head, bearing ribs and the middle bearing shell, lower inclined plate connecting the conical head, bearing ribs, the middle bearing shell and the outer upper bearing shell. 3 claims, 4 figures of drawings

IPC Classes  ?

• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat
• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of mechanical engineering and transporting, and more particularly to crane runways for nuclear power plant containment vessels. A crane runway for a nuclear power plant containment vessel comprises cantilever supports uniformly mounted in a circle and fastened at the same height to the inner side of the containment vessel with clearance from one another, and, mounted on top of said cantilever supports, a track in the shape of a circle having the radius of the crane runway, the track being fastened to the cantilever supports by fastening members. Each cantilever support is comprised of an upper horizontal plate and a lower horizontal plate mounted parallel with one another and fastened to one another by vertical longitudinal and transverse ribs. The plates and the transverse ribs are fastened by one end in the reinforced concrete structure of the containment vessel. Both sides of the ends of the plates oriented toward the containment vessel have lateral cutouts, and the upper part of the end face of the cantilever support at the opposite end from the containment vessel has a protruding ledge. The invention makes it possible to increase the robustness of a crane runway for the containment vessel of a nuclear power plant.

IPC Classes  ?

• B66C 7/00 - Runways, tracks, or trackways for trolleys or cranes

Abstract

The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of a nuclear reactor, increase of heat removal efficiency from corium of a nuclear reactor. The invention relates to the field of nuclear energy, in particular, to systems that ensure the safety of nuclear power plants (NPP), and can be used in severe accidents that lead to reactor pressure vessel and its containment destruction. The technical result of the claimed invention consists in increasing the reliability of the corium localizing and cooling system of a nuclear reactor, increase of heat removal efficiency from corium of a nuclear reactor. The technical result is achieved by using the membraned, drum and thermal protection installed in the area between the layered vessel and cantilever truss in the corium localizing and cooling system of a nuclear reactor.

IPC Classes  ?

• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

The invention relates to the field of nuclear power engineering, and more particularly to systems which provide for the safety of nuclear power plants, and can be used in the event of accidents leading to the destruction of the pressure vessel and sealed containment structure of a reactor. A system for confining and cooling melt from the core of a nuclear reactor comprises a guide device, a cantilever truss, a filler for receiving and distributing melt, said filler being disposed in a housing having water supply valves mounted around its perimeter and having a flange with a thermal shield mounted thereon, a drum mounted on the flange of said housing and being configured in the form of a casing with reinforcing ribs mounted around its perimeter on the inner side, said reinforcing ribs bearing against a cover and a bottom, wherein said drum has tensioning elements connecting the drum, via a support flange welded thereto, to the flange of the housing, and spacing elements providing an adjustment gap between the drum and the flange of the housing. Provided in the drum are nozzles equipped with heat reflectors and cooling ribs and having water supply valves mounted therein, for increasing the reliability of the system for confining and cooling melt from the core of a nuclear reactor.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to systems which provide for the safety of nuclear power plants, and can be used in the event of accidents leading to the destruction of the pressure vessel and sealed containment structure of a reactor. A system for confining and cooling melt from the core of a nuclear reactor comprises a guide device, a cantilever truss, a filler for receiving and distributing melt, said filler being disposed in a housing having water supply valves mounted around its perimeter and having a flange with a thermal shield mounted thereon, a drum mounted on the flange of said housing and being configured in the form of a casing with reinforcing ribs mounted around its perimeter on the inner side, said reinforcing ribs bearing against a cover and a bottom, wherein said drum has tensioning elements connecting the drum, via a support flange welded thereto, to the flange of the housing, and spacing elements. Provided in the drum are nozzles having water supply valves mounted therein with sealed covers, and hydraulic dampers connected to external sources of water and to the water supply valves by feed pipes, pressure pipes, compensating pipes and equalizing pipes, for increasing the reliability of the system for confining and cooling melt from the core of a nuclear reactor.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of nuclear power engineering, and more particularly to systems which provide for the safety of nuclear power plants, and can be used in the event of serious accidents leading to the destruction of the pressure vessel and sealed containment structure of a reactor. The aim of the invention is to prevent a system for confining and cooling melt from being destroyed in the zone where a housing for receiving and distributing melt is connected to a cantilever truss in the event that melt escapes from the pressure vessel in an axially asymmetric fashion and fragments of the bottom of the pressure vessel fall into the multilayer housing in the initial stage of the water cooling of the melt, and thus to prevent cooling water intended for cooling the outside of the housing from entering same. This aim is achieved in that a system for confining and cooling melt from the core of a nuclear reactor additionally comprises a heat shield suspended from the cantilever truss, a membrane mounted between the cantilever truss and the housing, and banding plates mounted on the inner and outer sides of said membrane.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of nuclear power engineering, and more particularly to systems which provide for the safety of nuclear power plants, and can be used in the event of serious accidents leading to the destruction of the pressure vessel and sealed containment structure of a reactor. The technical result of the claimed invention is an increase in the reliability of a system for confining and cooling melt from the core of a nuclear reactor. This technical result is achieved in that a system for confining and cooling melt from the core of a nuclear reactor comprises a membrane installed between a cantilever truss and a housing, shroud plates installed on the outer and inner sides of the membrane, and a hydro- and gas dynamic damper installed on the inner side of the membrane, which makes it possible to prevent damage in the zone where the multilayer housing is connected to the cantilever truss in the event that melt escapes in an axially asymmetric fashion from the pressure vessel and fragments of the bottom of the pressure vessel fall into the housing in the initial stage of the water cooling of the melt.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of nuclear power engineering, and more particularly to systems which provide for the safety of nuclear power plants, and can be used in the event of serious accidents leading to the destruction of the pressure vessel and sealed containment structure of a reactor. The technical result of the claimed invention is an increase in the reliability of a system for confining and cooling melt from the core of a nuclear reactor. This technical result is achieved by preventing a system for confining and cooling melt from being destroyed in the zone where a housing and a cantilever truss are connected by using in said system a membrane with banding plates, which is mounted on a drum.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

The invention relates to the field of atomic engineering, and more particularly to equipment for detecting leaks in and repairing damage to the inner lining of a water-filled spent fuel pool in a nuclear power station. An arrangement and system for repairing the lining of a spent fuel pool, and more preferably the walls and bottom thereof, are additionally equipped with devices that are not immersible in the spent fuel pool, inter alia, welding equipment, and devices that are immersible in the spent fuel pool, including an immersible repair platform for holding a working mechanism. Said working mechanism is equipped with a device for removing contaminants from weld seams and the surface of the spent fuel pool, and a wire cutting device comprising a receptacle for collecting cuttings and a pump for removing particles. A device for sealing leaks is configured in the form of a small-scale welding assembly coupled to welding equipment, and the immersible repair platform is equipped with means for securing it to the surface of the spent fuel pool. An arrangement for repairing the lining of a spent fuel pool includes an immersible repair robot having a working unit arranged thereon. The invention provides better quality, more reliable repair.

IPC Classes  ?

• G21C 17/07 - Leak testing

Abstract

Device for holes and trepans cutting containing a movable platform, a mechanism of rotation and feeding of the cutting tool installed on the platform, a box-shaped repair cabin with a through hole in a vertical wall thereof and, accommodating a positioning sleeve with an inner flange facing the inside of the repair cabin and an outer flange fixed outside the repair cabin. A mounting fixture secured on the inner flange of the positioning sleeve comprises a mounting plate fixed on the inner flange of the positioning sleeve. A rotating positioning plate is pivotally installed on the mounting plate. The mounting plate and the rotating positioning plate are provided with a mechanism for fixing in the closed position. The movable platform is provided with height-adjustable rotatable wheel supports. A catcher is fixed on the outer flange of the positioning sleeve for primary storage of cut trepans and collection of chips.

IPC Classes  ?

• B23B 39/14 - General-purpose boring or drilling machines or devicesSets of boring or drilling machines with special provision to enable the machine or the drilling or boring head to be moved into any desired position, e.g. with respect to immovable work
• B23B 51/04 - Tools for drilling machines for trepanning
• G21C 21/00 - Apparatus or processes specially adapted to the manufacture of reactors or parts thereof

Abstract

The invention relates to the field of atomic engineering, and more particularly to equipment for detecting leaks in and repairing damage to the inner lining of a water-filled spent fuel pool in a nuclear power station. An arrangement and system for repairing the lining of a spent fuel pool, and more preferably the walls and bottom thereof, are additionally equipped with devices that are not immersible in the spent fuel pool, inter alia, welding equipment, and devices that are immersible in the spent fuel pool, including an immersible repair platform for holding a working mechanism. Said working mechanism is equipped with a device for removing contaminants from weld seams and the surface of the spent fuel pool, and a wire cutting device comprising a receptacle for collecting cuttings and a pump for removing particles. A device for sealing leaks is configured in the form of a small-scale welding assembly coupled to welding equipment, and the immersible repair platform is equipped with means for securing it to the surface of the spent fuel pool. An arrangement for repairing the lining of a spent fuel pool includes an immersible repair robot having a working unit arranged thereon. The invention provides better quality, more reliable repair.

IPC Classes  ?

• G21C 17/07 - Leak testing

Abstract

A method for manufacturing nuclear reactor fuel assembly. The method comprises applying a protective coating on fuel elements, wherein each fuel element is moved through a protective coating application device installed on an assembly stand. The protective coating comprises a water-soluble lubricant consisting of nonylphenol ethoxylate and monobasic unsaturated fatty acids. The method further comprises installing the coated fuel elements into grid cells of an assembly, wherein during the installing, each coated fuel element is moved on the assembly stand in a horizontal direction along its own axis into the grid cells. At least part of the steps of applying a protective coating and installing the coated fuel elements occur simultaneously. After installing the coating, top and bottom nozzles are attached to the assembly. After attaching the top and bottom nozzles, the fuel elements are washed to remove the protective coating from the fuel elements, which are subsequently dried.

IPC Classes  ?

• G21C 3/334 - Assembling the bundles
• G21C 3/20 - Details of the construction within the casing with coating on fuel or on inside of casingDetails of the construction within the casing with non-active interlayer between casing and active material
• G21C 21/02 - Manufacture of fuel elements or breeder elements contained in non-active casings
• G21C 3/07 - CasingsJackets characterised by their material, e.g. alloys

Abstract

The invention relates to cleaning tubes of a tube bundle of a steam generator of a nuclear power plant. A device for cleaning heat exchange tubes of a steam generator of a nuclear power plant comprises: a manipulator which is moveably and fixably mounted in a vertical corridor between bundles of heat exchange tubes; a nozzle that is rotatably mounted on the manipulator and is in the form of a head of injectors connected to a pipeline for supplying high-pressure water jets; and means for remote control and video monitoring, wherein the manipulator is equipped with: a housing which is mounted on a guiding mounting frame and is connected to a base, a drive for main rotational movement which is disposed on the housing, a post which is connected to the housing and is in the form of a hollow column, a drive for auxiliary movement which is fastened on the post, a joint which is connected to the post and is in the form of a tube having a gear rack, and a joint of working elements and a coordinating head. The technical result is a decrease in the cleaning time and reliability of removal of deposits.

IPC Classes  ?

• F28G 3/16 - Rotary appliances using jets of fluid for removing debris
• F28G 15/02 - Supports for cleaning appliances, e.g. frames

Abstract

The invention relates to cleaning tubes of a tube bundle of a steam generator of a nuclear power plant. A device for cleaning heat exchange tubes of a steam generator of a nuclear power plant comprises: a manipulator which is moveably and fixably mounted in a vertical corridor between bundles of heat exchange tubes; a nozzle that is rotatably mounted on the manipulator and is in the form of a head of injectors connected to a pipeline for supplying high-pressure water jets; and means for remote control and video monitoring, wherein the manipulator is equipped with: a housing which is mounted on a guiding mounting frame and is connected to a base, a drive for main rotational movement which is disposed on the housing, a post which is connected to the housing and is in the form of a hollow column, a drive for auxiliary movement which is fastened on the post, a joint which is connected to the post and is in the form of a tube having a gear rack, and a joint of working elements and a coordinating head. The technical result is a decrease in the cleaning time and reliability of removal of deposits.

IPC Classes  ?

• F28G 3/16 - Rotary appliances using jets of fluid for removing debris
• F28G 15/02 - Supports for cleaning appliances, e.g. frames
• B08B 3/02 - Cleaning by the force of jets or sprays

Abstract

The invention relates to technical diagnostics. The claimed method consists in measuring vibration acceleration in three mutually orthogonal planes using vibration sensors mounted at monitoring points on a diesel generator. Vibration accelerations are measured at monitoring points on an operational known good diesel generator, and then vibration accelerations are measured at prescribed intervals at said monitoring points on the diesel generator when the latter is in operation. Temperature and the intensity of an ultrasonic signal are also measured at the aforementioned monitoring points, and the root mean square values of the ultrasonic signal intensity, the temperature and the vibration acceleration are determined. On the basis of the vibration acceleration values measured, the root mean square values of vibration velocity and vibratory displacement are calculated, the distances between clusters of preceding measurements are determined and a conclusion is drawn about the operating state of the diesel generator. The technical result consists in allowing the timely detection of operating defects in a diesel generator by carrying out periodic measurements and comparing the calculation results obtained with one another, thus also providing for the safety of technical equipment in plants.

IPC Classes  ?

• G01M 15/04 - Testing internal-combustion engines
• G01M 15/12 - Testing internal-combustion engines by monitoring vibrations

Abstract

The invention relates to a method for cleaning the surfaces of the tubes of a steam generator tube bundle in a nuclear power station. The method for cleaning the heat exchange tubes of steam generators in a nuclear power station consists in introducing a hydrodynamic manipulator connected to a hoist into a vertical passage inside a heat exchanger, taking preliminary measurements of the dose rate inside the steam generator, measuring eddy current signals and analyzing the signals received in order to assess the condition of the walls of the heat exchange tubes and the thickness of the deposits thereon, determining the coordinates of a cleaning sector and calculating the time and cleaning modes, emitting a high-pressure jet of water using at least one nozzle mounted for rotation about an axis of rotation, and moving the hydrodynamic manipulator according to the coordinates of the cleaning sector, wherein the water jet is set at a feed pressure of from 1000 to 1500 bar and a flow rate of from 100 to 150 l/min and the cleaning zone is subject to video monitoring. The technical result is a shorter cleaning time and more reliable removal of deposits.

IPC Classes  ?

• F28G 3/16 - Rotary appliances using jets of fluid for removing debris

Abstract

The invention relates to technical diagnostics. The claimed method consists in measuring vibration acceleration in three mutually orthogonal planes using vibration sensors mounted at monitoring points on a diesel generator. Vibration accelerations are measured at monitoring points on an operational known good diesel generator, and then vibration accelerations are measured at prescribed intervals at said monitoring points on the diesel generator when the latter is in operation. Temperature and the intensity of an ultrasonic signal are also measured at the aforementioned monitoring points, and the root mean square values of the ultrasonic signal intensity, the temperature and the vibration acceleration are determined. On the basis of the vibration acceleration values measured, the root mean square values of vibration velocity and vibratory displacement are calculated, the distances between clusters of preceding measurements are determined and a conclusion is drawn about the operating state of the diesel generator. The technical result consists in allowing the timely detection of operating defects in a diesel generator by carrying out periodic measurements and comparing the calculation results obtained with one another, thus also providing for the safety of technical equipment in plants.

IPC Classes  ?

• G01M 15/04 - Testing internal-combustion engines
• G01M 15/12 - Testing internal-combustion engines by monitoring vibrations

Abstract

The invention relates to the field of technical diagnostics and can be used for investigating the fluid-tightness of pipes and detecting leaks in pipes in nuclear power stations. Acoustic signals are recorded at two points along the length of a pipe, and the received acoustic signals are subsequently processed. The acoustic signals are recorded in a broad ultrasonic range at two points along the length of the pipe, said points being situated on the pipe upstream and downstream of a valve. The ultrasonic signals recorded at the point on the pipe upstream of the valve and at the point downstream of the valve are then processed, and the values obtained are used to construct two signal spectra. Next, a range of from 15000 to 90000 Hz is isolated and, within this range, the highest amplitude value in each of the signal spectra is selected. Then, the amplitudes of the signal spectra in said frequency range are divided by the highest amplitude value and the difference between the signal spectra upstream and downstream of the valve is determined using a mathematical formula, thereby making it possible to determine the degree of fluid-tightness of the pipe in order to assess its fitness for further service, as well as allowing better quality, more efficient detection of leaks in the pipe.

IPC Classes  ?

• G01M 3/24 - Investigating fluid tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using infrasonic, sonic, or ultrasonic vibrations
• F17D 5/02 - Preventing, monitoring, or locating loss

Abstract

The invention relates to the field of technical diagnostics and can be used for investigating the fluid-tightness of pipes and detecting leaks in pipes in nuclear power stations. Acoustic signals are recorded at two points along the length of a pipe, and the received acoustic signals are subsequently processed. The acoustic signals are recorded in a broad ultrasonic range at two points along the length of the pipe, said points being situated on the pipe upstream and downstream of a valve. The ultrasonic signals recorded at the point on the pipe upstream of the valve and at the point downstream of the valve are then processed, and the values obtained are used to construct two signal spectra. Next, a range of from 15000 to 90000 Hz is isolated and, within this range, the highest amplitude value in each of the signal spectra is selected. Then, the amplitudes of the signal spectra in said frequency range are divided by the highest amplitude value and the difference between the signal spectra upstream and downstream of the valve is determined using a mathematical formula, thereby making it possible to determine the degree of fluid-tightness of the pipe in order to assess its fitness for further service, as well as allowing better quality, more efficient detection of leaks in the pipe.

IPC Classes  ?

• F17D 5/02 - Preventing, monitoring, or locating loss
• G01M 3/24 - Investigating fluid tightness of structures by using fluid or vacuum by detecting the presence of fluid at the leakage point using infrasonic, sonic, or ultrasonic vibrations

Abstract

The invention relates to methods for diagnosing the technical condition of electrically driven equipment and can be used for monitoring vibrations in rotating equipment in nuclear power stations. The claimed method includes measuring and recording diagnostic signals in a test period while the equipment under inspection is in operation, dividing the recordings of a reference signal and a signal from the equipment under inspection into five segments of not less than two seconds in length, converting each segment of the recordings of the reference and inspection signals into a spectrum that represents the distribution of amplitudes across frequencies, sampling amplitudes of the spectra of the diagnostic signals of the inspected and fault-free equipment at the frequencies at which deviations appear between the inspection and reference signals, calculating the absolute differences of the amplitudes of the spectra of the inspected and fault-free equipment, ranking the absolute differences and summing the resultant ranks. The sum of the resultant ranks is compared with a critical value to establish whether the rotating equipment is in excess of prescribed vibration values, and to establish the presence of a fault if the sum of the resultant ranks exceeds the critical value.

IPC Classes  ?

• G01M 13/045 - Acoustic or vibration analysis

Abstract

The invention relates to methods for diagnosing the technical condition of electrically driven equipment and can be used for monitoring vibrations in rotating equipment in nuclear power stations. The claimed method includes measuring and recording diagnostic signals in a test period while the equipment under inspection is in operation, dividing the recordings of a reference signal and a signal from the equipment under inspection into five segments of not less than two seconds in length, converting each segment of the recordings of the reference and inspection signals into a spectrum that represents the distribution of amplitudes across frequencies, sampling amplitudes of the spectra of the diagnostic signals of the inspected and fault-free equipment at the frequencies at which deviations appear between the inspection and reference signals, calculating the absolute differences of the amplitudes of the spectra of the inspected and fault-free equipment, ranking the absolute differences and summing the resultant ranks. The sum of the resultant ranks is compared with a critical value to establish whether the rotating equipment is in excess of prescribed vibration values, and to establish the presence of a fault if the sum of the resultant ranks exceeds the critical value.

IPC Classes  ?

• G01M 13/045 - Acoustic or vibration analysis

Abstract

The invention relates to a method for cleaning the surfaces of the tubes of a steam generator tube bundle in a nuclear power station. The method for cleaning the heat exchange tubes of steam generators in a nuclear power station consists in introducing a hydrodynamic manipulator connected to a hoist into a vertical passage inside a heat exchanger, taking preliminary measurements of the dose rate inside the steam generator, measuring eddy current signals and analyzing the signals received in order to assess the condition of the walls of the heat exchange tubes and the thickness of the deposits thereon, determining the coordinates of a cleaning sector and calculating the time and cleaning modes, emitting a high-pressure jet of water using at least one nozzle mounted for rotation about an axis of rotation, and moving the hydrodynamic manipulator according to the coordinates of the cleaning sector, wherein the water jet is set at a feed pressure of from 1000 to 1500 bar and a flow rate of from 100 to 150 l/min and the cleaning zone is subject to video monitoring. The technical result is a shorter cleaning time and more reliable removal of deposits.

IPC Classes  ?

• F28G 3/16 - Rotary appliances using jets of fluid for removing debris
• B08B 3/02 - Cleaning by the force of jets or sprays

Abstract

Methods for non-destructive testing of engineering materials. In one aspect, a method can be used to calculate residual longitudinal and annular welding stresses in welded joints and can be used to assess the quality of pipeline welds according to the criterion of the level of residual stresses and to determine the initial parameters for the pipeline strength calculation. In some aspects, the method enables independent calculation of the longitudinal and hoop residual stresses. Thus, the stresses can be calculated in the seam metal of the pipelines welds, where they reach their maximum values. The method can be used to test a pipeline section using an ultrasonic echo method to measure the propagation time for longitudinal waves and transverse waves polarized along and across the pipe axis. The measurement results define the distinguishing features of the stress state of a welded joint for a specific type of pipe by numerical modeling.

IPC Classes  ?

• G01N 29/07 - Analysing solids by measuring propagation velocity or propagation time of acoustic waves

Abstract

Seal between mutually fixed surfaces comprises a metal ring, placed between graphite layers, where sections of the metal ring to be coated with graphite have a jagged profile. Both sides of the metal ring are coated with graphite in such a way that graphite layers and the metal ring form a seamless whole. Recesses are made in the seal on both sides between graphite rings, a hole is placed in their centre.

IPC Classes  ?

• F16J 15/08 - Sealings between relatively-stationary surfaces with solid packing compressed between sealing surfaces with exclusively metal packing

Abstract

Method for long-term dry storage of spent nuclear fuel includes injecting the inert gas into a cavity formed in a cask between inner and outer lids under pressure greater than the pressure of the inert gas in the inner cavity of the cask in which the spent nuclear fuel is located. The cask contains a body with a spent nuclear fuel container placed in it, tight inner and outer lids forming a cavity into which the inert gas is pumped under pressure greater than the pressure in the inner cavity of the cask. The outer lid comprises a labyrinth hole closed with a flange and sealed with a gasket. The flange comprises an angle valve, to which at least two pressure sensors are connected. The angle valve and sensors are covered with a protective cover during long-term storage. The gasket is installed in an annular groove of the lower flange.

IPC Classes  ?

• G21F 5/12 - Closures for containersSealing arrangements
• G21F 5/02 - Transportable or portable shielded containers with provision for restricted exposure of a radiation source within the container
• G21F 5/005 - Containers for solid radioactive wastes, e.g. for ultimate disposal
• G21F 5/008 - Containers for fuel elements
• G21C 17/07 - Leak testing

Abstract

This invention involves systems which provide for the safety of nuclear power plants that can be used in the event of serious accidents leading to the destruction of the housing and sealed containment structure of a reactor. In one aspect, the system can increase nuclear power plant safety by preventing the escape of liquid and solid radioactive materials (corium) from a melt confinement device in the event of a serious accident involving the escape of core melt from a nuclear reactor. The invention addresses the problem of increasing the efficiency and reliability of a melt confinement device by improving the conditions for cooling corium. The problem is solved by the use of a filler formed in upper cassettes and in a lower cassette. Said cassettes are configured with vertical and horizontal channels which provide for the uniform distribution of melt in the housing undergoing cooling.

IPC Classes  ?

• G21C 9/016 - Core catchers
• G21C 13/10 - Means for preventing contamination in event of leakage
• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

Steels and alloys for use in the nuclear power engineering industry during the manufacture of equipment, including manufacturing an in-vessel baffle of pressurized water power reactors (VVER) with a life less than 60 years. In one aspect, an austenite chromium-nickel steel is provided with increased resistance to swelling on impact of neutron flows at doses up to 150 dpa. In some aspects, the result is accomplished by adding molybdenum, calcium and rare earth metals (REM) lanthanum and cerium to steel containing carbon, silicon, manganese, chromium, nickel, titanium and iron at specified mass ratios.

IPC Classes  ?

• C22C 38/60 - Ferrous alloys, e.g. steel alloys containing lead, selenium, tellurium or antimony, or more than 0.04% by weight of sulfur
• C22C 38/58 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
• C22C 38/52 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with cobalt
• C22C 38/50 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
• C22C 38/44 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
• C22C 38/42 - Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
• C22C 38/02 - Ferrous alloys, e.g. steel alloys containing silicon
• C22C 38/00 - Ferrous alloys, e.g. steel alloys

Abstract

Apparatus for drying Spent Ion-Exchange Resins (SIER), which can intensify the SIER drying process, reduce power consumption, and accelerate discharge of SIER when the drying process is completed. The apparatus comprises a sealed cylindrical body, and a blow-down choke installed in an upper part of the sealed cylindrical body and a nozzle to feed the spent ion-exchange resins is installed inside the body, and a nozzle to retrieve dried ion-exchange resins is installed in its bottom part and equipped with a locking device. An external heater is provided for the body, and a drive shaft that is installed in alignment inside the body, capable of rotation, and equipped with a stirrer. A lower part of the drive shaft with lower screw winding is installed in alignment inside the nozzle to retrieve dried ion-exchange resins. The nozzle to retrieve dried ion-exchange resins is equipped with a water draining device.

IPC Classes  ?

• F26B 9/08 - Machines or apparatus for drying solid materials or objects at rest or with only local agitationDomestic airing cupboards in stationary drums or chambers including agitating devices
• G21F 9/16 - Processing by fixation in stable solid media
• F26B 25/04 - Agitating, stirring, or scraping devices
• G21F 9/28 - Treating solids

Abstract

Method and device for the preparation of monophasic powders of actinide salts which are precursors in the production of fuel pellets. In one aspect, a compact and simple device is provided to obtain dry monophasic powders of actinide salts in one stage, while increasing the productivity, chemical and nuclear safety of the process. In a second aspect, the method comprises feeding of nitric actinides-containing solution and formic acid to a cylindrical heated reactor, grinding the resulting powder, and discharging the powder. The nitric actinides-containing solution and formic acid are continuously metered to the upper zone of the reactor so that the reactive chemicals are mixed in a thin film on the heat-exchange surface, where the reaction mixture is continuously stirred by rotor blades. Also occurring are the processes of denitration, formation of the relevant compounds, their drying and grinding and collecting dry salts of actinides in a hopper by gravity.

IPC Classes  ?

• C07C 51/41 - Preparation of salts of carboxylic acids by conversion of the acids or their salts into salts with the same carboxylic acid part
• B01D 1/06 - Evaporators with vertical tubes
• B01D 1/22 - Evaporating by bringing a thin layer of the liquid into contact with a heated surface
• B01J 19/18 - Stationary reactors having moving elements inside
• G21C 3/62 - Ceramic fuel

Abstract

A device for confining nuclear reactor core melt comprising a melt trap and provided with a multilayer vessel containment, a filler, an upper support, and a bottom support comprising a horizontal embedded plate mounted in the concrete of a reactor pit. The plate comprises radial supports, the melt trap comprising radial supports, based on the radial support of the plate. The plate radial supports and the melt trap radial supports are connected with fasteners having holes in the form of hyperbolic surfaces. The radial supports and the clamps have oval holes. The upper support comprises turnbuckles, mounted in pairs on the upper part of the melt trap body so that the longitudinal axis of each radial support of the melt trap bottom support passes in projection at an equispaced distance from the fitting location of the paired turnbuckles and connecting the melt trap body with the reactor pit vertical wall.

IPC Classes  ?

• G21C 9/016 - Core catchers

Abstract

System for confining and cooling melt from the core of a water-moderated nuclear reactor comprising a melt trap. The melt trap is installed in the reactor vessel bottom and provided with a cooled containment, consisting of outer and inner housings between which there is a sealant, and the filler for the melt dilution placed in the melt trap inner body. The melt trap inner body has a damper consisting of a central mantle, bearing ribs connected with the central mantle, titled plates, placed between the bearing ribs, the stops providing fastening of the damper to the melt trap body.

IPC Classes  ?

• G21C 9/016 - Core catchers
• G21C 15/18 - Emergency cooling arrangementsRemoving shut-down heat

Abstract

The invention can be used for cutting out holes and cylindrical through samples from the housing of a nuclear reactor. The present device comprises a mechanism for rotating and feeding a cutting tool, and a movable platform. A vertical wall of a maintenance cabin is provided with a through-hole for a positioning bushing that has a mounting assembly fastened to an inside flange thereof, said mounting assembly comprising a mounting plate and, hingedly mounted thereto, a pivotable positioning plate. Said plates are provided with a mechanism for fixing the plates in an interlocked position. The movable platform is equipped with height-adjustable pivotable wheeled supports, is mounted inside the maintenance cabin on the floor thereof, is rigidly fastened to a gusset plate of the pivotable positioning plate, and comprises a mechanism for rotating and feeding a cutting tool. Fastened to an outside flange of the positioning bushing is a catching member for catching trepanned samples and collecting shavings. The invention allows operations to be performed easily and safely.

IPC Classes  ?

• B23B 35/00 - Methods for boring or drilling, or for working essentially requiring the use of boring or drilling machinesUse of auxiliary equipment in connection with such methods
• G21C 19/00 - Arrangements for treating, for handling, or for facilitating the handling of, fuel or other materials which are used within the reactor, e.g. within its pressure vessel

Abstract

The invention relates to the field of mechanical engineering, namely to process equipment for nuclear power industry. The objective of the present invention is to ensure the convenience and safety of work when performing process operations for cutting trepans at one workplace in a limited space of the repair cabin. The technical result achieved by the proposed invention is to ensure the accuracy of the alignment of the cutting tool and reduce the cutting tool installation time and, as a result, reduce the radiation exposure loads on the service personnel. This technical result is achieved due to the fact that the device for holes and trepans cutting containing a mechanism of rotation and feeding of the cutting tool and a movable platform is, according to the present invention, further provided with a box-shaped repair cabin performing the role of a device body, with a through hole made in a vertical wall of the repair cabin, the said hole accommodating a positioning sleeve mounted with an inner flange facing the inside of the repair cabin and an outer flange fixed outside the repair cabin, with a mounting fixture secured on the inner flange of the positioning sleeve, where the said mounting fixture comprises a mounting plate fixed on the inner flange of the positioning sleeve and a rotating positioning plate pivotally installed on the mounting plate with a possibility of rotating around the vertical axis, where the mounting plate and the rotating positioning plate are provided with a mechanism for fixing in the closed position, the movable platform is provided with height- adjustable rotatable wheel supports installed inside on the bottom of the repair cab and rigidly attached to the gusset of the rotating positioning plate, the mechanism of rotation and feeding of the cutting tool is installed on the movable platform with the mounting and rotating positioning plates being in the closed position coaxially with the positioning sleeve, and a catcher is fixed on the outer flange of the positioning sleeve for primary storage of cut trepans and collection of chips. Preferably, the movable platform of the device for holes and trepans cutting is a spatial truss with height-adjustable rotatable wheel supports. The device for holes and trepans cutting may be provided with a fixture for branding trepans before cutting the same, including a hollow cylindrical body, end covers installed at the ends of the cylindrical body having groove holes made on them along the diameter line, connected to each other in pairs on different end covers by through guide tubes placed inside the cylindrical body, a rod for branding trepans placed in one of the guide tubes, with a removable striker at one end and a digital stamp on the other, and removable plugs installed in the other guide tubes, where the outer surface of the cylindrical body is made according to the running fit for installation inside the positioning sleeve, and the space inside the cylindrical body between the guide tubes is filled with lead shot to a part of the length of the cylindrical body. The device for holes and trepans cutting is preferably provided with a lead safety plug installed in the positioning sleeve from the end facing the inside of the repair cabin. The mechanism of rotation and feeding of the cutting tool of the device for holes and trepans cutting may be implemented in the form of a drilling machine, preferably pneumatic, and the cutting tool is implemented in the form of a core drill. A drilling fixture of the device for holes and trepans cutting may be made in the form of a hollow cylinder provided with end caps installed at its ends, with central holes made in them, interconnected by a hollow tube configured to accommodate an ejector and to supply a cooling fluid to the cutting tool, where one of the end caps has a mounting bore for installing the cutting tool, and the other end cap is configured to be installed and fixed in the chuck of the drilling machine.

IPC Classes  ?

• B23B 41/00 - Boring or drilling machines or devices specially adapted for particular workAccessories specially adapted therefor
• B23B 47/00 - Constructional features of components specially designed for boring or drilling machinesAccessories therefor

Abstract

The invention relates to nuclear engineering, and more particu- larly to the drying of spent ion-exchange resins. An apparatus for drying spent ion-exchange resins comprises: a hermetically sealed cylindrical housing hav- ing in the top part thereof a bleed nozzle and a pipe for feeding spent ion-ex- change resins into the housing, and having in its bottom part a pipe for remov- ing dried spent ion-exchange resins which is provided with a closing device; an external heater for heating the housing; and also a drive shaft coaxially and ro- tatably mounted inside the housing and equipped with an agitator. Said agitator is configured in the form of an anchor impeller, the blades of which are shaped to be conformal with the inside surface of the bottom and side parts of the hous- ing, and codirectional upper and lower screw flights arranged on the drive shaft above and below the point of attachment of said anchor impeller. The lower part of the drive shaft with the lower screw flight is arranged coaxially inside the pipe for removing dried spent ion-exchange resins. The pipe for removing dried spent ion-exchange resins is provided with a means for draining water. The invention makes it possible to reduce the time and energy intensiveness of the process of drying spent ion-exchange resins.

IPC Classes  ?

• G21F 9/28 - Treating solids

Abstract

The invention relates to metallurgy of alloyed steels and alloys that are intended for use in nuclear power engineering in the production of main equipment for nuclear power plants, namely for the manufacture of an internal baffle for pressurized water reactors (PWR) with a service life of at least 60 years. The technical result of the present invention is the creation of an austenitic nickel-chromium steel that has increased swelling resistance when exposed to neutron fluxes at doses of up to 150 dpa. The technical result is achieved in that molybdenum, calcium and the rare-earth metals (REM) lanthanum and cerium are additionally introduced into the composition of a known steel containing carbon, silicon, manganese, chromium, nickel, titanium, and iron with the ratio of elements as follows: 0.06-0.10 wt% carbon, 0.40-0.60 wt% silicon, 1.50-2.00 wt% manganese, 15.0-16.0 wt% chromium, 24.00-26.00 wt% nickel, 0.70-1.40 wt% molybdenum, (5 * carbon content + 0.10) - 0.80 wt% titanium, 0.001-0.003 wt% calcium, 0.001-0.005 wt% lanthanum and cerium, < 0.035 wt% phosphorus, < 0.008 wt% sulfur, < 0.020 wt% nitrogen, < 0.025 wt% cobalt, < 0.3 wt% copper, < 0.001 wt% tin, < 0.001 wt% antimony, < 0.001 wt% arsenic, < 0.001 wt% bismuth, < 0.001 wt% lead, and the remainder being iron. Moreover, in order to most fully achieve the technical result, the following ratios should simultaneously be used: The chromium equivalent, calculated according to the formula CCr eq=CCr+CMo+1.5*CSi+0.5*CTi, should not exceed the value Ceq/Cr<18.0, where CCr is the chromium content, wt%; CMo is the molybdenum content, wt%; CSi is the silicon content, wt%; and CTi is the titanium content, wt%. The nickel equivalent, calculated according to the formula CNi eq=CNi+30*CC+0.5*CMn+30*CN, should not be below the value of Ceq/Ni<27?5, where CNi is the nickel content, wt%; CC is the carbon content, wt%; CMn is the manganese content, wt%; and CN is the nitrogen content, wt%. The proposed austenitic nickel-chromium steel with a nickel content of 25% makes it possible to achieve the indicated technical result (increased resistance to swelling while maintaining the required mechanical properties).

Abstract

The group of inventions relates to non-destructive testing of engineering materials. It can be used for the calculation of residual longitudinal and annular welding stresses in welded joints and can be used to assess the quality of the pipelines welds according to the criterion of the level of residual stresses and to determine the initial parameters for the pipeline strength calculation. The technical result of the claimed group of inventions is to provide the possibility of independent calculation of the longitudinal and hoop residual stresses. Thus, the stresses are calculated in the seam metal of the pipelines welds, where they reach their maximum values. The technical result of the invention according to the first embodiment is provided in that in the method of the calculation of residual stresses in the weld metal of pipelines welds, consisting in that on the pipeline section under tests the propagation time for longitudinal waves and transverse waves polarized along and across the pipe axis are measured with the ultrasonic echo method, and the measurement results define the distinguishing features of the stress state of a welded joint according to the claimed solution for a specific type of pipe by numerical modeling to pre-define the position of the cross-sections balancing, which balancing the hoop stresses in the base metal reaches the minimum value, and the balancing coefficient value, equal to the ratio of the maximum membrane residual tensile hoop stresses in the seam metal to the value of the minimum residual compressive membrane hoop stresses in the base metal. Further, prior to the welded joints completion, measurements of the initial values of the propagation time of the longitudinal wave and transverse waves polarized along and across the pipe axis are performed in the balancing sections are performed; after the welded joints completion at the same measurement points, measurements of the performance values of the propagation time of the same types of waves are performed, according to the results of measurements applying the acoustoelasticity equations for a biaxial stress state: where tol, t02, t03 are the initial and ti, t2, t3 are the performance values of the propagation times of the transverse waves polarized along and across the generating line of a tube and longitudinal wave, respectively, K1 and K2 are the coefficients of the acoustic- elastic linkage, for each section of measurements, the values of membrane longitudinal and hoop stresses are calculated, as well as bending moments, using which, based on the principle of balancing membrane stresses and taking into account the balancing coefficient, the maximum values of residual longitudinal and hoop local stresses in the seam metal are calculated. The technical result of the invention according to the second embodiment is provided in that in the method of the calculation of residual stresses in the weld metal of pipelines welds made of the acoustically isotropic metal, consisting in that on the pipeline section under tests the propagation time for the bulk waves are measured with the ultrasonic echo method, and the measurement results define the distinguishing features of the stress state of a welded joint according to the claimed solution for a specific type of pipe by numerical modeling to pre-define the position of the cross-sections balancing, which balancing the hoop stresses in the base metal reaches the minimum value, and the balancing coefficient value, equal to the ratio of the maximum membrane tensile hoop stresses in the seam metal to the value of the minimum compressive membrane hoop stresses in the base metal and also the value of the intrinsic acoustic anisotropy of the base metal. After the welded joint completion, in the balancing sections, measurements of the performance values of the propagation time of transverse waves polarized along and across the pipe axis are performed, according to the results of measurements using the acoustoelasticity equation for the difference between the longitudinal and hoop membrane stresses the specified difference for each measuring point is calculated: where, ao is the intrinsic acoustic anisotropy of the base metal, D is the elastic-acoustic coupling coefficient, the separation of longitudinal and hoop membrane stresses is performed using the results of defining the longitudinal stresses in the additional section, then for each measurement section, the values of membrane longitudinal and hoop stresses are calculated, as well as bending moments, using which, based on the principle of balancing membrane stresses and taking into account the balancing coefficient, the maximum values of residual longitudinal and hoop local stresses in the seam metal are calculated. 21

IPC Classes  ?

• G01N 29/07 - Analysing solids by measuring propagation velocity or propagation time of acoustic waves