The automatic production line of fuel elements and their grading

 

(57) Abstract:

Usage: the invention relates to nuclear power and may find application in the manufacture of fuel elements. The inventive automatic production line of rods and their grading device prepare membranes for equipment with welding stub to one end of the shell, the device equipment column of fuel pellets in the open end of the shell, the device mounting clamps into the open end of the filled shell, the control device and sorting in the presence of internal defects and the length of the compensation gap method gamma scanning device sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under the shell, the control device and formation pressure within the shell of a fuel rod placed after the sealing device, the device surface chemical treatment of shell fuel with oxidation and device control and grading curb fuel rods in diameter, length and curvature. The control unit diameter is made in the form of a first optical system including spaced with one hand Proc. of the axes of the fiber optic bundles with regular styling and rectangular ends, placed on the borders of light and shade provided with the radiation detector. The control unit curvature is made in the form of a second optical system with an intermediate optical system performed similarly to the first optical system and second optical system together with the interim is located on the base a distance from the first optical system and the intermediate optical system is located equidistant from the first and second optical systems. The control unit of length is made in the form of the third optical system is similar to the first and hosted from a stop at a distance equal to the maximum length of a fuel rod, and the outputs of all detectors are outputs of all control units. 5 Il.

The invention relates to nuclear power and may find application in the manufacture of fuel elements (cartridges), mainly for nuclear power reactor VVER.

In the nuclear power industry is known for the automatic production line of fuel rods containing preparation device of the membranes to the equipment with welding stub to one end of the shell, the device equipment column of fuel pellets in the open end of the shell, the device mounting tabs opened in Ansalonga gap method gamma scan, the device is sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under the shell, the control device and formation pressure within the shell of a fuel rod placed after the sealing device, the device surface chemical treatment of shell fuel with oxidation, the control device and formation of a loaded fuel rods in diameter, length and curvature, are placed in a single process stream with a cut off piece of issuance, tilt tables, sensors, control system, automatic lines, vehicles wiring device-to-device and device to output the defective fuel rods [1].

In the process of manufacturing fuel rods may vary in diameter, the length of a fuel rod and defects in the curvature, which does not allow to deliver high-quality Assembly of fuel rods in the fuel assemblies.

The use of defective shells curvature for equipment fuel rods will cause seal failure thereof during operation of the fuel assemblies in a nuclear reactor due to the touch of the fuel rods each other violations of heat removal and burn fuel in place of touch.

In addition, the control and rysbrack the AMI with the measurement error of 12% - 15% and is not precluded by the misalignment and jamming of the rollers, causing damage to the zirconium sheath of the fuel element. Mechanical damage to the zirconium sheath of a fuel rod (sdiri, scratches and other) lead to pitting corrosion in places damage during operation in a nuclear reactor and is not excluded them depressurization.

An object of the invention is to improve the quality of fabrication of fuel elements. The solution to this problem is achieved in that in the automatic production of fuel rods and their grading containing preparation device of the membranes to the equipment with welding stub to one end of the shell, the device equipment column of fuel pellets in the open end of the shell, the device mounting clamps into the open end of the filled shell, the control device and sorting in the presence of internal defects and the length of the compensation gap method gamma scanning device sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under the shell, the control device and formation pressure within the shell of a fuel rod, posted by after sealing device, the device surface chemical treatment of obvezna, housed in the same process stream with a cut off piece of issuance, tilt tables, sensors, control system, automatic lines, vehicles wiring device-to-device and device to output the defective fuel rods, according to the invention the control unit diameter is made in the form of a first optical system including spaced from one side of the vehicle two fiber and two lenses, and on the other hand perpendicular to the optical axes of the fiber optic bundles with regular styling and rectangular ends, placed on the borders of light and shade provided with the radiation detector, the control unit curvature is made in the form of a second optical system with an intermediate optical system, performed similarly to the first optical system and second optical system together with the interim is located on the base a distance from the first optical system and the intermediate optical system is located equidistant from the first and second optical systems, the control unit of length is made in the form of the third optical system is similar to the first and hosted from a stop at a distance equal to the maximum length of a fuel rod, and the control and inspection of the fuel rods in diameter, the curvature and length will help to improve the quality control due to non-contact measurement and inspection of the fuel rod length, diameter, curvature, to avoid damage to the fuel elements and to improve the quality of fabrication of fuel elements.

In Fig. 1 shows the automatic production line of rods and their formation; Fig. 2 - tilt table inspection of a fuel rod of Fig. 3 is a diagram of the device control and inspection of a fuel rod according to the pressure of the inert gas inside; Fig. 4 is a diagram of the optical system control units; Fig. 5 - scheme of the combined control units for internal defects and gaps.

The automatic production line of rods and their grading device 1 preparation of membranes to the gear unit 2 gear rods, device 3 sealing of the fuel rods, the device 4 surface treatment of the fuel rods, the device 5 grading of the fuel rods (shown by the dashed line in Fig.1).

The device 1 preparation of membranes to the outfit includes inclined at an angle of 3 to 5-rack and pinion table 6, along which technological sequence posted by: moving in the axial direction mechanisms 7 pieces of tubing in size; the mechanism 8 control the length of the tube 9, the mechanism 10 calibration one end of the tube 9.

nna surfaces of the tubes of shell 9 with the movement mechanisms of the bath in the tub (not shown).

For tubs placed second rack and pinion tilt table 12, along which in the process sequence includes: a pressing mechanism 13 of the stub 14 in the calibrated end of the tube-shell 9(later shell), the mechanism 15 weighing, electron beam 16 for welding stub 14 to the shell 9, the Stripping mechanism 17 of the weld and the mechanism 18 ultrasonic testing of the weld. For filing shell 9 on the unit 2 equipment designed roller 19.

The unit 2 equipment includes vibrating table 20 supply column of fuel pellets 21 at the open end of the shell 9, the inclined rack and pinion table 22, along which technological sequence posted by: mechanism 23 mounting clamps 24 and the mechanism 25 cleaning the open end of a filled shell 9 from the dust.

For submission of filled shell 9 with pressed therein by latches 24 for further operations designed roller 26. The roller 26 is mounted device 27 of the combined control unit and grading of the fuel rod internal defects and the length of the compensation gap method gamma scan, kickers 28 fit curb shells 9 (hereafter Fe) on the vehicle - roller conveyors 29 and 30 and in the collection of marriage 35.

The sealing device 3 includes two units 36 and 37 contact-butt welding stub 38 to the shell 9 (hereafter Fe) under the pressure of the inert gas under the wrapper, mechanism 39 and 40 supply plugs into the welding zone.

Coaxially to the axis of movement of the fuel rod 9 and the roller 29 and 30 mounted devices 41 and 42 of the control and inspection pressure within the shell of a fuel rod 9 and the mechanisms 43 and 44 of the ultrasonic weld inspection.

For supply of a fuel rod 9 to the device 4 surface treatment with an oxidizing the surface of the zirconium sheath of a fuel rod used roller conveyors 29 and 30 with reversing engines.

The automatic production line of a fuel rod is further provided with a vehicle: roller 45 and 46 of the wiring of the fuel rod 9 to the device 5 grading of the fuel rod 9 in diameter, curvature and length of the fuel element.

Each of the two devices 41 and 42 of the control and inspection pressure within the shell of a fuel rod 9 (Fig. 2) includes a tilt table 47 lessors-off valves 48 of a fuel rod 9 on the roller 29 and 30. In Fig. 2 shows the roller 29 with the kickers-raspakovyvaya 49.

Each of the two devices 41 and 42 of the control and inspection pressure within the shell of a fuel rod (Fig. 3) contains the photosensor 5 is m and the pressure roller 51 to the input of a fuel rod 9 and output control, the block 52 of the heat expansion clearance of a fuel rod 9 in the form of an inductor with a high frequency generator 53, a power source 54 and the stabilizer 55, the unit of measurement of temperature of 56 item 57 of rotation of the fuel rod 9, the photosensor 58 stop of a fuel rod 9, the two semiconductor thermistors 59 included in the bridge circuit 60, two voltmeters 61 measuring signals of the bridge circuit block 62 computer-based microelectronic computing machines, automatic block 63, the printing device 64.

The device 5 grading of the fuel rod (Fig.1 in the plan) may be made in the form of two process streams grading of the fuel rod 9 (the drawing shows two threads).

Each of the flow control and inspection of the fuel rod 9 includes placed along the vehicle (table 45 and 46) control units and grading of the fuel rod 9 to a diameter of 65, the curvature 66, length 67, raspakovyvat 68 supply of defective fuel rods on the tilt table 69 in the cartridge 70, kickers 71 of suitable rods on sloping desks 72 tapes 73 and the sensor 74.

In the device 5 grading of the fuel rods (Fig.1) in the scheme (Fig.4) optical systems control units control unit diameter 65 of the fuel rod is made in the form of the first optical system, including raspologen, but on the other hand mutually perpendicular optical axes of the fiber optic bundles 79 - 82 regular styling and rectangular ends, placed on the borders of the shadows, communicated with the receiver 83 radiation, the preprocessing block 84 and the microcomputer 85.

Unit 66 controls the curvature of a fuel rod is made in the form of a second optical system with intermediate optical components, performed similarly to the first optical system and second optical system together with the interim is located on the base length L1"equal to 250 mm from the first optical system, the intermediate optical system is located between the first and second optical systems at an equal distance.

Unit 67 controls the length of the fuel rod 9 is made in the form of the third optical system is similar to the first and hosted from a stop 86 on the distance L equal to the maximum allowable length of a fuel rod 9, and the outputs of all detectors are outputs of all control units. The control unit 27 (Fig.1) internal defects, combined with a device for measuring clearances (Fig.5) based on the gamma scan, contains a detection unit 87 and block gamma radiation 88 and second detection units 89 and gamma radiation 90, Mimi channels 92, the pulse generator is controlled frequency 93, the first valve device 94, the registration unit 95, 96 move the controlled fuel rod 9, the display device measurement results 97, the sensor 98 start and end sensor 99 to the base segment, the second valve device 100. the comparator 101, the arithmetic unit 102, the eddy-current sensor 103, a digital display 104 and tsifropechatayuschee device 105.

The automatic production line of fuel elements and their grading is as follows.

Device 1 is the preparation of membranes to the equipment. On the inclined table 6 billet tube enters the mechanisms 7 a section of tubing in the size of the shell, control 8 the length of the tube-shell 9, calibration 10 one end of the tube shell. Further, the tube-shell 9 passes baths 11 degreasing, rinsing, and drying of the inner and outer surfaces. On the inclined rack table 12 tube-shell 9 is fed to the pressing mechanism 13 of the stub 14 in the calibrated end of the tube-shell 9 (hereinafter shell 9), on the mechanism 15 weighing on electron-beam installation 16 for welding stub 14 to the shell 9, the Stripping mechanism 17 of the weld and the mechanism 18 ultrase on the vibrator 20 is formed pillar 21 fuel pellets of uranium dioxide, enriched uranium 235, and is loaded into the shell 9. On the inclined rack table 22 curb shell 9 is supplied to the mechanism 23 mounting clamps 24 and the mechanism 25 cleaning the open end of a filled shell of dust.

With pressed detents 24 curb shell 9 (hereafter Fe) of the roller 26 is supplied to the device 27 of the combined control unit and inspection of fuel elements by the method of gamma scanning for internal defects and gaps.

Due to the perpendicular placement (Fig. 5) detection units 87 and 89 and block gamma radiation 88 and 90 in a protective screens 91 roaming TVEL 9 illuminated by the collimated beam of gamma rays from all sides through collimation channels 92.

When moving a controlled fuel rod acts on the control input of the pulse generator, for example a roller 96, the speed of which is proportional to the speed of movement of the controlled fuel element.

The speed of rotation of the roller 96 determines the frequency of the pulses at the output of the generator 93, which is also proportional to the speed of movement of the controlled fuel rod. At that moment, when on the path of gamma rays is the gap (i.e., the attenuation of the beam sharply Menolly with generator arrives at the recording unit 95.

At the end of the gap signal at the output of detection units 87 and 89 decreases dramatically increases the attenuation of a beam of gamma rays) and the first valve device 94 is closed, stopping the flow of pulses from the generator to the recording unit 95. The amount registered in the registration unit of the pulses determines the magnitude of the gap. Simultaneously with the measurement gap, with the passage of the controlled fuel rod 9 through the sensor 98 start basic plot of the signal from the sensor opens the second valve device 100 and the pulses from the pulse generator is controlled frequency 93 come to the comparator 101.

With the passage of the controlled fuel rod 9 through the sensor end 99 of the basic plot of the signal from the sensor closes the second valve device 100, stopping the flow of pulses from the generator to the comparator 101. Thus, the comparator will register the number of pulses, which in the case of the health of the generator and the video will be proportional to the length of the base segment. When the wear of the roller or the failure of the generator is the number of pulses will change. In the comparator registered number of pulses is compared to a reference num is edelstam about the health of the roller, and if different from unity, it shows its wear and requires correction in the measurement gaps. The measurement of clearances from the registration unit 95 and the result from the comparator 101 is output to the arithmetic unit 102, where are multiplied by a factor equal to the ratio registered in the device for comparing the number of pulses from the generator and the control number.

Of the arithmetic unit 102, the corrected measurements and the ratio of the unit of comparison is coming to the display device 97. To increase the likelihood of detecting chips and gaps of fuel pellets, partially filled with crumbs, TVEL illuminated two streams of gamma-quanta in two mutually perpendicular directions. In this case, signal the beginning of the gap, Scola is speeding account with at least one detection unit, and signal the end of the gap - reducing the count rate below the threshold release with both detection units.

When the signal from the eddy-current sensor 103 on the display device measurement results 97 the values of the clearances between the holder and the tablet, the distance from the edge of the latch d is 104 and tsifropechatayuschee device 105, where prints the sequence number of a fuel rod, the number of crumbs, the compensation gap, maximum gap between the holder and the tablet, the gap between the bottom cover and the tablet, the distance from the edge of the latch until the tablet, the sum of the clearances, control the length and number of tabs.

When the detected deviations from the requirements TVEL 99 roller 26 is directed to the rejection with the help of raspakovyvaya 33 (Fig. 1), which shed defective fuel rod 9 on the tilt table 34 and the collector 35, and suitable cartridges 9 the same roller 26 are directed to further operations, where the kickers 28 are discharged on to the conveyor 29 or by an inclined table 32 on the conveyor 30. The roller 29 and 30 provided with a reversible motors 31 and the rods 9 are directed to the sealing device 3.

Using reversible motors 31 to the roller 29 and 30 sets the right-hand or left-hand rotation. The signal sensors (not shown) during rotation of the motors 31 kerb shell 9 (Fe) is an open end in the installation of the contact-butt welding 36 or 37, there are served stub 38 through mechanisms 39 and 40 and the welding stub 38 to curb the shell is carried out under pressure of inert gas, for example helium. Th is th 31 is output from the welding zone and is directed by-vehicles roller 29 and 30 in the devices 41 and 42 of the control and inspection pressure within the shell of a fuel rod 9. The device 41 and 42 of the control and inspection TVEL consistently included in the element 57 (Fig. 3) rotation of the fuel rod 9 around its axis, in block 52 of the heat compensation gap (gap without pills uranium dioxide), rests on the cutter sensor 48 and presses the pressure roller 51. The photosensor 50 gives the command "TVEL on the control, and the photosensor 58 - "stop TVEL". Using a high-frequency generator 53, a power source 54 and stabilizer included 55 block 52 of the heat expansion clearance of a fuel rod 9 and this area of the fuel rod is heated.

The principle is based on excitation of the test fuel rod convective motion of the gas and measuring the increment of the temperature at the points of the shell of a fuel rod 9 caused by the convective component of heat transfer using block 56 measurement temperatures.

The increment of the cladding of a fuel rod 9 is controlled by two semiconductor thermistors 59 included in the bridge circuit 60 and two voltmeters 61 measuring signals of the bridge circuit. The first voltmeter measures the temperature difference between the sensors corresponding to the convective component of heat transfer. The second voltmeter is the sum of the temperature sensors.

Information with voltmeters 61 enters nl 64, transforming information in the gas pressure in atmospheres with ranges: lower limit of - 1.0 MPa (10 ATM); the upper limit is 3.0 MPa (30 ATM).

The performance of a single thread - 90 PCs/h, and two 80 PCs/h In the cases when the gas pressure in the fuel rod 9 below, it follows that the shell of a fuel rod 9 will not be sealed. This TVEL 9 dumper-raspokovyvaem 49 (Fig. 2) is reset to an inclined rack and pinion table 47 and into the collection.

Fit the fuel rods 9 and the roller 29 or 30 act on the mechanisms 43 and 44 of ultrasonic testing of the weld (Fig. 1) and these roller conveyors are fed to the device 4 surface treatment with the oxidation of a fuel rod 9.

The roller 45 and 46 of the rods 9 are fed to the control device 5 and grading of the fuel rod 9, which are sequentially controlled by the diameter of the blocks 65 of the control and inspection of the fuel rod 9 in diameter by creating mutually perpendicular light beams from the LEDs 75 and 76 (Fig. 4) through the lenses 77 and 78 on the edge of a fuel rod 9 and the fiber optic bundles 79 - 82, providing input on the ends withing the boundaries of light and shade from the edges of the irradiated fuel elements 9. Light fluxes with the boundaries of light and shade on fiber optic bundles are transferred to the radiation detector 83, block provisional obrai TVEL 9 is discharged from the conveyor 45 or with the roller 46 on the tilt table 69 and into the cassette 70 for defective fuel rods.

In blocks 65 and 66 on the base length L1(Fig. 1) through the intermediate optical system is defined by analogy with the block 65 border of light and shade that fiber optic bundles are transferred to the radiation detector 83, the preprocessing block 84 and the microcomputer 85, where in the case of deviations in the curvature TVEL 9 raspokovyvaem 68 is reset with the roller 45 or 46 on the tilt table 69 and into the cassette 70.

In block 67 (Fig.1) control the length of the fuel rod 9, is placed against the stop 86 (Fig. 4) at a distance L equal to the maximum allowable length of a fuel rod with an optical system that transmits the border of light and shade on fiber optic harness, control the length of each fuel rod 9.

By fiber optic bundles border of light transmitted to the light receiver 83, the preprocessing block 84 and the microcomputer 85.

In case of rejection of the length of a fuel rod 9 from the set, TVEL 9 raspokovyvaem 68 is reset to the tilt table 69 and into the cassette 70. Fit the fuel rods 9 and the roller 45 and 56 are fed into the lock to sensors 74 and with kickers 71 is discharged at the inclined tables 72 and in the transport cassette 73.

The automatic production line of fuel elements and their grading containing device prepare what's tablets in the open end of the shell, the device mounting clamps into the open end of the filled shell, the control device and sorting in the presence of internal defects and the length of the compensation gap method gamma scanning device sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under the shell, the control device and formation pressure within the fuel cladding placed after the sealing device, the device surface chemical processing of the fuel cladding by oxidation, the control device and grading curb fuel elements according to the diameter, length and curvature, are placed in a single process stream with a cut off piece of issuance, tilt tables, sensors, control system, automatic lines, vehicles wiring device-to-device and device for output of defective fuel elements, characterized in that the control unit diameter is made in the form of a first optical system including spaced from one side of the vehicle two fiber and two lenses, and with the other hand on vseyslishanie on the borders of light and shade, communicated with the radiation detector, the control unit curvature is made in the form of a second optical system with an intermediate optical system performed similarly to the first optical system and second optical system together with the interim is located on the base a distance from the first optical system and the intermediate optical system is located equidistant from the first and second optical systems, the control unit of length is made in the form of the third optical system is similar to the first and hosted from a stop at a distance equal to the maximum length of the fuel element, and the outputs of all detectors are outputs of all control units.

 

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