Process line for manufacturing fuel elements

FIELD: nuclear power engineering; manufacture of fuel elements for fuel assemblies of power reactors.

SUBSTANCE: proposed process line has mechanism for weighing can charged with fuel pellets installed past retainer press-fitting mechanism; can is coupled through computer with mentioned weighing mechanism for outputting data on pure mass of pellets in can; γ-quanta detecting units and pellet enrichment automatic control installations are mounted on charged can guiding facility in the form of rolling train between its rollers throughout length of charged pellet stack; detecting units are disposed around pellet stack charged in can with collimation channels shifted throughout length of charged pellet stack; detecting units are provided with photoelectronic multipliers, spectrometers, and data acquisition, processing and outputting computer. Each detecting unit is provided with through hole passing can-displacement tungsten tube; shifted collimation channels are provided in top and bottom parts of tungsten tube; photoelectronic multipliers are disposed on butt-ends of detecting unit.

EFFECT: enhanced quality of fuel element manufacture.

3 cl, 3 dwg

 

The invention relates to the nuclear industry and can find application in the manufacturing of fuel elements for nuclear reactors.

Known for the automatic production line of fuel elements (FE)containing devices:

- preparation of the membrane to the equipment by welding plugs to one end of the shell, vibrating equipment column of fuel pellets in the open end of the shell, comprising a vibratory feeder feed fuel pellets on a horizontal cradle for the formation of the pillars of fuel pellets, the selectors - stops beginning of the pillars, the selectors - clamps the ends of the pillars fuel pellets, a Desk with a cradle for laying them in the shells open ends toward and aligned with the pillars of fuel pellets with the mechanisms of installation and removal of loaded shells,

- Stripping of the open end of the filled shell, measuring the length of a column of fuel pellets,

- mounting clamps into the open end of the filled shell,

- sealing by welding the caps to the open end of the filled shell under the pressure of the inert gas under the shell,

control and inspection pressure within the shell (hereafter FE) and by the presence of internal components

- surface treatment of TVEL, vehicle wiring of a fuel rod from device to device, you the ode defective TVEL and automation system (see the patent of Russian Federation №2070740, IPC G 21 C 21/02 from 17.05.94,, publ. 20.12.1996,

On the well-known lines may produce either Fuel for WWER-1000, or the Fuel of VVER-440, as they are different lengths (3837 mm and 2500 mm), and the line provides for the production of fuel Rods of the same size.

The line provides for the weighing of the shell, but does not weigh loaded shell, i.e. does not determine the weight of the column of fuel pellets in the shell.

In addition, the control and classification of the internal components in the famous lines is performed after the sealing of a fuel rod, i.e. if the control fuel element mismatch is detected by the presence of internal components, you will need rasteklovki of a fuel rod and remove fuel pellets with the conclusion in the marriage of the shell.

According to the requirements of the Fuel elements for the normal operation of a nuclear reactor, avoid distortions in the neutron and temperature fields in each fuel rod must be strictly specified number of nuclear fuel (fissile isotope) and uniform distribution along the length of the fuel element.

The equipment of the fuel Rods must do fuel pellets from a strictly specified enriched in U235strictly defined length of the column of fuel pellets, a given density and a given weight of fuel in a fuel rod (see Development, production and operation of fuel elements ene is power reactors. Book 2. Edited Fgurative. - M.: Energoatomizdat, 1995, s).

These requirements known to the automatic production line of the fuel element does not match, because not determined the enrichment of U235fuel pellets loaded shell and it was hit in the equipment TVEL one type of enrichment tablets tablets different enrichment for mass production.

The closest in technical essence and the achieved effect is the automatic production line of the fuel rod containing devices:

- preparation of the membrane to the equipment with its weighing and welding stub to one end of the shell,

- vibration equipment column of fuel pellets in the open end of the shell, comprising a vibratory feeder feed fuel pellets on a horizontal cradle countertops with clipper-emphasis of the beginning of the pillars and the cutter-clamp the end of the pillars of fuel pellets adjacent to the table top Desk with a cradle styling shells open ends of the aligned columns of fuel pellets with the mechanisms of laying, feeding on the equipment and removing the filled shells, cleaning, pressing, clamps, control and inspection on the internal components and the means of posting on the seal,

- sealing by welding the caps to the open end of the filled shell under pressure and artego gas under the shell, control and inspection pressure within the shell of a fuel rod, ultrasonic testing of the weld seam

- surface treatment of the Fuel rod is provided with a detachable extension tubes for fuel Rods of a nuclear reactor VVER-440, tools, wiring device-to-device output defective TVEL and automation system (see Russian Federation Patent CC IPC 7 G 21 21/02 from 17.02.1999,, publ. 27 August 2000) - the prototype.

Automatic line-prototype eliminates the disadvantages of the known line in terms of expanding the technological capabilities of manufacturing a Fuel of VVER-1000 and VVER fuel Rods-440 on one line, control and sorting by the presence of internal components to seal the filled shell that allows you to take prompt action without moving the sheath in a marriage that took place in the famous line.

However, the direct weighing of the loaded fuel rod to determine the mass of fuel in the fuel rod line-prototype does not. There are control and detection of fuel pellets with the other enriched in U235in the column of fuel pellets, which differs from the fuel pellets with a specific enrichment in U235.

The technical challenge is to improve the quality of manufacturing of the fuel rod with the definition of the mass and length of a column of fuel pellets in a fuel rod and control enrichment in U235preserving the rhythm of release of the fuel elements.

This technical problem is solved in that in the automatic lines for manufacturing fuel elements containing devices:

- preparation of the membrane to the equipment with its weighing and welding stub to one end of the shell with a removable extension tubes for fuel Rods of a nuclear reactor VVER-440;

- vibration equipment column of fuel pellets in the open end of the shell, machinery cleaning, pressing, clamps, control and inspection on the internal components and the means posting on a seal in the form of a roller,

- sealing by welding the caps to the open end of the filled shell under the pressure of the inert gas under the shell, control and sorting in the pressure inside the shell of a fuel rod, ultrasonic testing of the weld seam

- surface treatment of Fe,

- funds transaction device-to-device output defective fuel elements and system automation

according to the invention, after the pressing mechanism latches in the open end of the filled fuel tablets shell established a mechanism for weighing loaded fuel tablets membranes interacting via computer with the weighing mechanism of the shell with the issuance of data on the net weight of the fuel pellets in the shell, the means of the posting curb fuel tablets shell in the form of a roller conveyor between its rollers along a length of the e loaded into the shell of the column of fuel pellets installed detection units γ quanta emitted by U235fuel pellets, install automatic monitoring of enrichment in U235in the fuel pellets fuel elements for light water power reactors VVER-1000 and VVER-440, the detection units are placed around the curb into the shell of the column of fuel pellets offset collimation channels along the length of the curb into the shell of the column of fuel pellets, the number of detection units along the length of the column of fuel pellets in the shell installed sufficient to ensure the travel speed unladen fuel tablets sheath according to the rhythm of the production of fuel elements and the detection units are equipped with photoelectron multipliers, spectrometers and computer collection, processing and outputting data to identify fuel pellets deviation of enrichment in U235and their location in the column of fuel pellets.

Another difference is that each detection unit on the basis of the scintillator sodium iodide activated with thallium NaJ(Tl)with orifice - tungsten tube moving through it filled with fuel tablets shell, offset collimation channels made in tungsten tube at the top and the bottom, and photomultipliers featu the wife on the ends of the detecting unit. Installation of automatic control automatic line is equipped with a drive of marriage and the kickers with the roller loaded shells with identified disabilities by mass, enrichment U235the length of the column of fuel pellets to the drive of marriage.

The proposed automatic production line of fuel elements can improve the quality of manufacturing of the fuel element by determining the mass and length of a column of fuel pellets in a fuel rod, enrichment U235to isolate the curb shell deviation mentioned above and to keep the rhythm of release of the fuel element.

The drawings show the automatic production line of fuel elements, where

in Fig. 1 - General view of the automatic lines for manufacturing fuel elements,

in Fig. 2 - installation of automatic control,

in Fig. 3 - installation diagram of automatic control.

The automatic production line of fuel elements contains:

device 1 preparation of the shell 2 to the equipment with its weighing 3 and welding 4 stub 5 to one end of the shell 2 with a removable extension 6 for fuel Rods of a nuclear reactor VVER-440,

device 7 vibrating equipment fuel pellets 8 in the open end of the shell 2, the clearance mechanisms 9, the fitting 10 clamps 11, control and inspection 12 on the internal components and environments is the primary objective in posting to seal in the form of a roller conveyor 13,

device 14 of the sealing weld stub 15 to the open end of the filled shell 2 under the pressure of the inert gas under the shell, the control device 16 and formation pressure within the shell 2 (hereafter Fe), ultrasonic testing 17 weld

device 18 surface treatment of the fuel Rods,

- funds transaction device-to-device output defective TVEL and automation system (not shown).

After pressing mechanism 10 of the latches 11 to the open end of the filled fuel tablets 8 shell 2 has a mechanism 19 weighing loaded shell 2, interacting through the computer 20 with the weighing mechanism 3 of the shell 2 with the issuance of data on the pure mass of fuel pellets 8 in Fe. The means of the posting - table 13 curb fuel tablets 8 shell 2 between the rollers along the length of the curb to the shell 2 of a column of fuel pellets 8 are installed detection units 21 γ-quanta emitted by U235, fuel pellets, 8, install automatic monitoring of enrichment in U235in the fuel tablets 8 fuel elements for light water power reactors VVER-1000 and VVER-440. Detection units 21 are placed around the curb to the shell 2 of a column of fuel pellets 8 offset collimation channel 22 along the length of the ammunition is tion in the casing 2 of a column of fuel pellets 8.

The number of detection units 21 along the length of the column of fuel pellets 8 in the shell 2 is sufficient to ensure the travel speed unladen fuel tablets 8 shell 2 according to the rhythm of release of the fuel Rods and the detection units 21 provided with a photoelectron multipliers 23, spectrometers 24 and the computer 25 of the collection, processing and outputting data to identify fuel pellets 8 deviation of enrichment in U235and their location in the column of fuel pellets 8.

Each detection unit 21 on the basis of the scintillator sodium iodide activated with thallium NaJ(Tl)with bushing holes - tungsten tube 26 move through it filled with fuel tablets 8 of the shell 2. Offset collimation channels 22 in the top and bottom parts of the tungsten tube 26. Photomultipliers 23 placed on the ends of the detecting unit 21.

Installation of automatic control automatic line is equipped with a drive of marriage 27 and kickers 28 with the roller 13 filled shells 2 with the identified deviations in weight, enriched in U235the length of the column of fuel pellets 8 to the drive of marriage 27. The roller 13 is also placed kickers 29 Postings filled shells 2 for further operations.

Automatic line made what I TVEL works as follows.

Installation 1 preparation of the casing 2 after welding 4 stub 5 to one end of the shell 2 and weighing 3 data weighting are transmitted to the computer 20.

For shells TVEL nuclear reactor VVER-440, having a length of ~ 2.5 m, apply the removable extension 6, to compensate for the length of a fuel rod and use automatic line for production of TVEL VVER-1000 without its changeover to release TVEL VVER-440, i.e. on the automated line, it becomes possible to release the fuel rod with a length of 2.5 m and 4 m.

The use of vibrating equipment 7 the column of fuel pellets 8 equip in the open end of the shell 2.

After cleaning, 9, fitting 10 clamps 11 curb fuel tablets 8 shell 2 is subjected to testing and grading 12 to the internal components and the roller 13 is directed to the seal 14. On the roller 13 during the movement of loaded fuel tablets 8 shell 2 is subjected to testing and grading along the length of the column of fuel pellets 8, enrichment U235and the identification of fuel pellets deviation of enrichment in U235and their location in the column of fuel pellets 8. Thus curb fuel tablets 8 shell 2 passes successively through the through holes tungsten tube 26 with offset holes collimation channels 22 detection units 21, and γ-quanta, ispos aimie U 235are perceived by the detection units, photoelectron multipliers 23, spectrometers 24 and fed to the computer 25, where the information is processed and issued data or for rejection or subsequent operation, i.e kickers 28 marriage to the drive 27 or resetter 29 valid.

Mass U235in running casing 2 is determined by direct weighing 19, the results of which are transmitted to the computer 20, where there is already evidence the weight of the empty shell 2 and exactly what was the second weigh-in.

The device 14 of the sealing carry out welding stub 15 to the open end of the filled fuel tablets 8 shell 2 under the pressure of the inert gas under the shell. On devices 16 they control the pressure inside the fuel rod, and the device 17 ultrasonic testing of the weld.

Controlled by the fuel Rods received by the device 18 surface treatment - washing, oxidation of the membrane, washing and drying of the Fuel elements.

1. The automatic production line of fuel elements containing preparation device shell to the equipment with its weighing and welding stub to one end of the shell with removable extension tube for fuel elements of nuclear reactors VVER-1000 and VVER-440, vibrating equipment column of fuel pellets in the open end of the shell, m is the cleaning mechanisms, mounting clamps, control and inspection on the internal components and the means posting on a seal in the form of a roller, seal welding the caps to the open end of the filled shell under the pressure of the inert gas under the shell, control and inspection pressure within the fuel cladding, ultrasonic weld inspection, surface treatment of fuel elements, tools, wiring device-to-device output defective fuel elements and the automation system, wherein after the pressing mechanism latches in the open end of the filled fuel tablets shell established a mechanism for weighing loaded fuel tablets membranes interacting via computer with the weighing mechanism of the shell with the issuance data on net weight of fuel pellets in the shell, the means of the posting curb fuel tablets shell in the form of a roller conveyor between its rollers along the length of the curb into the shell of the column of fuel pellets installed detection units γ-quanta emitted by U235fuel pellets, install automatic monitoring of enrichment in U235in the fuel pellets fuel elements for light water power reactors VVER-1000 and VVER-440 units detective the Oia placed around the curb into the shell of the column of fuel pellets offset collimation channels along the length of the curb into the shell of the column of fuel pellets, the number of detection units along the length of the column of fuel pellets in the shell installed sufficient to ensure the travel speed unladen fuel tablets sheath according to the rhythm of the production of fuel elements and the detection units are equipped with photoelectron multipliers, spectrometers and computer collection, processing and outputting data to identify fuel pellets deviation of enrichment in U235and their location in the column of fuel pellets.

2. Line according to claim 1, wherein each detection unit on the basis of the scintillator sodium iodide activated with thallium NaJ(T1)with orifice - tungsten tube moving through it filled with fuel tablets shell, offset collimation channels made in tungsten tube at the top and the bottom, and photomultipliers are located on the ends of the detecting unit.

3. Line according to claim 1, characterized in that the installation of an automatic control automatic line is equipped with a drive of marriage and dumper with the roller equipped the shells with the identified deviations in weight, enriched in U235the length of the column of fuel pellets to the drive of marriage.



 

Same patents:

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EFFECT: enlarged functional capabilities of process line for manufacturing fuel-element cans of different sizes.

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SUBSTANCE: proposed process line has mechanism for weighing can charged with fuel pellets installed past retainer press-fitting mechanism; can is coupled through computer with mentioned weighing mechanism for outputting data on pure mass of pellets in can; γ-quanta detecting units and pellet enrichment automatic control installations are mounted on charged can guiding facility in the form of rolling train between its rollers throughout length of charged pellet stack; detecting units are disposed around pellet stack charged in can with collimation channels shifted throughout length of charged pellet stack; detecting units are provided with photoelectronic multipliers, spectrometers, and data acquisition, processing and outputting computer. Each detecting unit is provided with through hole passing can-displacement tungsten tube; shifted collimation channels are provided in top and bottom parts of tungsten tube; photoelectronic multipliers are disposed on butt-ends of detecting unit.

EFFECT: enhanced quality of fuel element manufacture.

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EFFECT: enhanced reliability of fuel assembly, reduced manufacturing cost and structural material input.

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