The automatic production line of fuel elements

 

The invention relates to the nuclear industry and can find application in the manufacturing of fuel elements for nuclear reactors. Technical result: automation control and grading curb membranes by weight of the fuel column, the exception oscillations of the mass of fuel and invalid local bursts of energy release in the core during operation of a nuclear reactor, reducing labor costs for maintenance of electron beam welding installations stub to the shell. In automatic lines before installing the sealing mechanism installed weighing curb fuel cladding with uniform weights and a single weighing device with vertical racks for stacking them curb the fuel cladding. Between the posts posted by the rotary feeders filled shells on the vertical posts of the weighing device and removal of them when the rotation of the rotary mechanisms. The weighing mechanism is equipped with a computer and a programmable controller. Programmable controller carries out the stop line when the discrepancy between the weight set weight with sorting as shell and equipped to find application in the manufacturing of fuel elements (Fe), for nuclear pressurized water reactors (VVER).

Known for the automatic production line of fuel rods containing devices: - preparation of membranes to the equipment with welding stub to one end of the shell; - equipment of the column of fuel pellets in the open end of the shell; - mounting clamps into the open end of the filled shell; - sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under cover; control and inspection pressure inside of the fuel cladding, placed after the sealing device; monitoring and inspection by the presence of internal components; - surface treatment placed in a single stream, equipped with a vehicle wiring device-to-device and device to output the defective fuel rods (see Patent EP 0192137, IPC G 21 C 21/02, 1986. ).

Known for the automatic production line of rods does not provide for a single process flow, the placement of the Stripping mechanism of the weld after welding stub to one end of the tube shell in preparation device shell to the equipment, resulting in concealment of possible defects in the weld, i.e. lastly the VVER-440, i.e. they have different lengths (3837 mm and 2500 mm), and the line provides for the production of fuel rods of the same size.

Known for the automatic production line of fuel elements (see Russian Federation Patent 2070740, IPC G 21 C 21/02 from 17.05.1994, publ. 20.12.1996) containing: - installation preparation of membranes to the equipment of the fuel rods, comprising an inclined rack table, along which technological sequence posted by mechanisms pieces of tubing with two parties in the amount of membrane for a fuel rod, a mechanism to control the length of the tube-shell, the calibration mechanism one end of the tube-shell adjacent to the inclined table adjacent bath degreasing and drying of the inner and outer surfaces of the tube-shell adjacent to the baths inclined rack table, along which technological sequence posted mechanism mounting bracket into the grooved end of the tube wrapper, mechanism for weighting shell the installation of electron-beam welding the caps to the shell, the Stripping mechanism of the weld, the mechanism of ultrasonic weld inspection; - the installation of wyposarzenia column of fuel pellets in the open end of the shell with a mechanism for stacking and feeding shells on equipment and removal saraganatam into the open end of the filled shell;
- installation of sealing the open end of a filled shell feeder stub and weld it to the shell under the pressure of the inert gas under cover;
- control mechanism and formation pressure within the shell of a fuel rod, the presence of internal components;
- installation surface treatment with the oxidizing surface of the membrane of a fuel element embodying the wiring device-to-device output defective fuel rods and system automation.

Automatic line eliminates the disadvantages of the known lines in parts cleaning welds on the shell after electron-beam welding the caps to the shell, but cannot be used for the manufacture of fuel rods of two modifications for nuclear reactor VVER-1000 and VVER-440 because of the different lengths of the rods.

In the famous line capacity of the weighing mechanism of the tube-shell before the electron-beam welding the caps to the shell, but not provided for weighing loaded shell, i.e. accounting loaded nuclear fuel is carried out only by the length of the curb of the column of fuel pellets, but not his weight that does not eliminate fluctuations in the mass of fuel in the fuel elements and invalid local bursts of energy release in reticency reactors". Book 1 edited by F. G. Reshetnikov. M.: Energoatomizdat, 1995. S. 213).

In the technical solutions according to the patent EP 0192137 and patent RU 2070740 control is provided and the sorting by the presence of internal components that is carried out after the sealing of a fuel rod, i.e., if the control will be identified marriage of the integrity of the fuel column, the total and single gap between the fuel pellets, chips, crumb fuel pellets, clamps and so on, you will need rasteklovki of a fuel rod with the destruction of the shell and possible partial destruction of fuel pellets at rasteklovki of a fuel rod.

In addition, due to the large length of the tube-shell - 3837 mm and low axial stiffness, is practically zero, when the weighting was used two scales with two coaxial with the cradle to prevent bending and deformation of the tube-shell, which created the well-known problems when you perform this operation because the required approval of two weights one weight - tube-shell, i.e., it was required to constantly observe the alignment of scales, finding the lifting devices on the same line perpendicular to the axis scales, and at the same height.

Permissible height difference should not exceed 1 mm When determining the weight of the shell must b the deposits may display a large number of shells in marriage by weight and disrupt the production rhythm, or Vice versa, throw in the annual shell rejected by weight of the shell.

In the process of mass production of fuel elements inevitably the use of multiple units of electron-beam welding the caps to the shell, each of which is equipped with a computer system to support the process with high accuracy (on beam current, accelerating voltage, the speed of rotation of the product, and so on (see "Development, production and operation of power reactors". Book 1 edited by F. G. Reshetnikov. M.: Energoatomizdat, 1995. S. 208...212).

The presence of the operator on each setting under computer control system necessarily requires a correspondingly increased labor costs.

Closest to the technical essence and the achieved effect is the automatic production line of fuel elements (see Russian Federation patent RU 2155395, MPK7 G 21 21/02 from 17.02.1999, publ. August 27, 2000), contains:
- installation preparation of membranes to the equipment which includes an inclined rack table, along which technological sequence posted by mechanisms pieces of tubing in the size of the shell, control the length of the tube-shell adjacent to the inclined table bath degreasing, rinsing, and drying, premika the m mounting bracket into the grooved end of the tube-shell (later shell), the weighing mechanism of the shell, the e-beam stubs to the shell, the Stripping mechanism of the weld, the mechanism of ultrasonic weld inspection and money transactions from mechanism to mechanism with automatic system;
- installation of wyposarzenia column of fuel pellets in the open end of the shell with the mechanisms stacking and feeding shells on the equipment and removing the filled shells;
device Stripping of the open end of the filled shell;
device mounting clamps into the open end of the filled shell;
- the mechanism of control and inspection on the internal components;
- installation sealing contact butt welding stub to curb the shell under the pressure of the inert gas helium under cover;
- control mechanism and formation pressure within the fuel element;
the mechanism of ultrasonic testing of the weld;
- installation surface treatment membrane of a fuel rod;
vehicles posted from mechanism to mechanism suitable cladding, outputs the defective fuel rods and automation system.

Automatic line - prototype eliminates the disadvantages of the known lines in the part placement mechanism counter the case of detection of defects and deviations from normal values is not difficult for operator intervention on the elimination of deviations without destroying the shell, because at the moment the shell has an open end, for the production of fuel rods of the two versions of the VVER-1000 and VVER-440 by using extension cords for fuel of VVER-440 and displacement sensors, however, suffer from lack of mechanism after weighing equipment, the use of two scales for weighing shell and servicing of electron-beam installations remain.

Technical challenge is the automation of the control and grading curb membranes by weight of the fuel column, the exclusion of oscillations of the mass of fuel and invalid local bursts of energy when operating in the active zone of the nuclear reactor, and reduced labor costs for maintenance of electron beam welding installations stub to the shell.

This technical problem is solved in that in the automatic production of fuel elements containing:
- installation preparation of membranes to the equipment which includes an inclined rack table, along which technological sequence posted by mechanisms pieces of tubing in the size of the shell, length control, calibration one end of the tube-shell adjacent to the inclined table bath degreasing, rinsing, and drying, adjacent to the baths naklonnyi in the grooved end of the tube-shell (later shell), the weighing mechanism of the shell, install the e-beam welding the caps to the shell with computer control systems electron beam welding, the Stripping mechanism of the weld, the mechanism of ultrasonic weld inspection and money transactions from mechanism to mechanism with automatic system;
- installation of wyposarzenia column of fuel pellets in the open end of the shell with the mechanisms stacking and feeding shells on the equipment and removing the filled shells;
device Stripping of the open end of the filled shell;
device mounting clamps into the open end of the filled shell;
- the mechanism of control and inspection on the internal components;
- installation sealing contact butt welding stub to curb the shell under the pressure of the inert gas helium under cover;
- control mechanism and formation pressure within the shell of a fuel rod;
the mechanism of ultrasonic testing of the weld;
- installation surface treatment membrane of a fuel rod;
vehicles posted from mechanism to mechanism suitable cladding, outputs the defective fuel rods and automation system;
according to the invention before installation of hermeti what trojstva with vertical racks for stacking them filled shell of a fuel rod, between which is placed a rotary feeders filled shell of a fuel rod to the upright support of the weighing device and removal of them when the rotation of the rotary mechanisms, the weighing mechanism is equipped with a computer and a programmable controller which carries out the stop line when the discrepancy between the weight set weight with sorting as shell and filled shell, computer systems control units of electron-beam welding stub to the membranes provided by the findings of the control parameters on beam current, accelerating voltage, the speed of rotation of the fuel rod at the joint panel screen display of all parameters and control modes of welding, United into a single system of automatic control of technological processes with the ability to analyze and diagnose component parts of the electron beam installations.

Other differences is that the distance between the posts of the weighing device, eliminating the deflection and deformation of the shell of a fuel rod is not more than 250 mm

Accommodation mechanism immediately after weighing equipment column of fuel pellets in the open end of the shell allows you to determine the weight of the column of fuel pellets in each of the th column with the specified, take appropriate measures to generatenew or removal of tablets from the fuel column to the level specified without destroying the membranes, since the operation of the equipment shell has an open end.

Computer relationship between mechanisms weighing shell and filled shell allows you to determine the net weight of the column of fuel pellets in each filled shell that prevents the extradition to fit rods with overweight or underrun of the fuel material fuel pellets and eliminate invalid local bursts of energy when operating in the active zone of the nuclear reactor.

The use of a single scale with a single weighing device for weighing operations shell instead of two scales with two weighing devices each weighing transaction will exclude adjust the alignment of scales, alignment of the weighing device, to reduce labour costs for adjustment, to halve the error of weighing and release equipment weighing.

Execution of a load device with vertical posts with the distance between the posts not more than 250 mm would eliminate deflection and deformation as shells and filled the shell size is Volochek and removal of the latter from the weighing mechanisms will allow you to automate this process.

Supply mechanisms weighing shell and filled the shell of the computer, programmable controller with electric connection will allow you to automate this process and to take into account the weight of each shell and stop the line when the mismatch weight.

The integration of computer control systems all installations electron beam welding output control settings on the integrated remote with a screen displaying all parameters and control modes of welding will allow the process from one operator for all installations of electron beam welding and diagnose component parts of the electron beam installations that will reduce labor costs.

The drawings show:
- Fig.1 - the automatic production line of fuel rods;
- Fig.2 is a block diagram of the weighing mechanism;
- Fig.3 - the weighing mechanism.

The automatic production line of fuel elements containing a plant for the preparation of membranes 1 to the equipment which includes an inclined rack and pinion table 2, along which technological sequence posted by mechanisms segments 3 tubes in the size of the shell 1, control 4, length calibration 5 one end of the tube-shell 1, primol 7, along which technological sequence posted by the pressing mechanism 8 plugs 9 in the calibration end of the tube-shell 1 (hereinafter shell 1), the weighing mechanism 10 of the shell 1, the installation of 11 e-beam welding stub 9 to the shell 1 with computer systems 12 control of electron-beam welding, the Stripping mechanism 13 of the weld, the mechanism of ultrasonic inspection 14 weld and means posting from mechanism to mechanism with automatic system (not shown);
- installation 15 wyposarzenia column of fuel pellets 16 in the open end of the shell 1 with the mechanisms stacking and feeding shells on the equipment and removing the filled shells 1;
the Stripping device 17 of the open end of the filled shell 1;
- pressing device 18 of the tabs 19 in the open end of the filled shell 1;
mechanism 20 of the control and inspection on the internal components;
- installation 21 sealing contact butt welding stub 22 to curb the casing 1 under the pressure of the inert gas helium under cover;
- mechanism 23 of the control and inspection pressure within the fuel element;
the mechanism 24 ultrasonic testing of the weld;
- installation surface 25 is shells and rods, outputs of defective fuel rods and automation system (not shown).

Before installing the seal 21 is mounted the mechanism for weighing loaded shell 1 of a fuel rod with uniform weights 26 and a single weighing device 27 with vertical posts 28 to 29 laying them filled shell 1 of a fuel rod with the distance between the posts 28, excluding the deflection and deformation of the loaded shell 1 of a fuel rod, which is placed between the rotary mechanisms 30 places 31 submission of filled shell 1 of the fuel rods in the space 29 to the fuel intake device 27 in axial coincidence of the axes of the seats 29, 31 to the fuel rods during rotation of the rotary mechanism 30 and removal of the shell 1 when the coincidence of the axes of the seats 29, 32, the weighing mechanism is equipped with a computer 33 and the programmable controller 34.

On the mechanism of the weighing carried out data output on the net weight of the pillars of fuel pellets 16 without shell 1 of each fuel element to the stop line when the discrepancy between the weight set weight with sorting as the shell 1, and loaded shell.

The computer control system 12 units 11 electron beam welding stub 9 to the shell 1 is combined with the output of the control current of the beam, accelerating e.g. welding, United into a single system of automatic control of technological process with the ability to analyze and diagnose component parts of the electron beam installations.

The distance between the vertical posts 28 of the weighing device 27, excluding the deflection and deformation of the shell 1 of a fuel rod is not more than 250 mm

Rotary mechanisms 30 are made in the form of nozzles on the shaft with some of the fuel rods 31, the orbit of rotation which passes through the axis of the seat rods 29 of the weighing device 27 and the axis of the reception and removal of the shell 1 with the weighing device.

The automatic production line of fuel elements is as follows.

On the inclined rack and pinion table 2, the tube is fed to the mechanism 3 pieces of tubing in the size of the shell 1, the control mechanism 4 of a length and on the mechanism 5 calibration at one end. After calibration tube-shell 1 in baths 6 passes degreasing, rinsing and drying, and is supplied to a rack and pinion tilt table 7, where the calibrated end of the pressing mechanism 8 zapressovyvajutsja cap 9.

The shell 1 is pressed by the cap 9 on the mechanism 10 is weighed and installation 11 electron beam welding stub 9 is welded to the shell 1.

Compact 1 is equipped with the conclusions of the parameters of the control current of the beam, the accelerating voltage, the speed of rotation of the fuel rod at the joint panel 35 with the screen display of all parameters and control modes welding, United into a single system of automatic control of technological process with the ability to analyze and diagnose component parts of the electron beam installations 11.

On the mechanism 13 Stripping is Stripping the weld, and the mechanism 14 check the quality of the weld by ultrasonic method.

Vehicle shell 1 serves for the installation of 15 wyposarzenia pillars of fuel pellets 16 simultaneously six shells at their open ends, and then to the device 17 Stripping of the open end of the filled shell from the dust of the fuel material, the device 18 mounting tabs 19 in the open end of the shell and on the mechanism 20 of the control and inspection on the inside, where the discrepancy between the specified components loaded sheath is withdrawn from the process for the adoption of measures aimed at integrating components, and suitable equipped shell 1 is directed to a mechanism for weighing scales 26, where the swivel mechanism 30 through 31 places to fuel rods loaded shell 1 is placed in the space 29 for the TVEL verteilter 33 and a programmable controller 34, where there are already data on the weight of the weighed shell weighing mechanism 10 empty shell 1.

When the net weight of the column of fuel pellets 16 specified curb shell 1 is directed to the seal, and in case of discrepancy between the curb weight of the shell 1 is output from the stream for the adoption of measures to bring the weight in accordance with the set.

The second rotary mechanism 30 through 32 places for fuel rods loaded shell 1 is removed from the field 29 for fuel rods and 21 by contact-butt welding stub 22 to the casing 1 under the pressure of helium under the shell.

After controlling gas pressure under the membrane on the mechanism 23 is suitable sealed curb shell 1 of a fuel rod is directed to ultrasonic control mechanism 24, and the marriage with mechanism mechanism 23 and 24 is withdrawn from the process.

After oxidation of the surface membrane of a fuel rod on the installation surface 25 of the processing cartridges are forwarded to the Assembly of fuel assemblies.


Claims

1. The automatic production line of fuel elements containing the installation of the preparation of the membranes to the equipment, including inclined rechniewski, length control, calibration one end of the tube-shell adjacent to the inclined table bath degreasing, rinsing, and drying, adjacent to the baths inclined rack table, along which technological sequence posted mechanism mounting bracket into the grooved end of the tube wrapper, mechanism for weighting shell, install the e-beam welding the caps to the shell with computer control systems electron beam welding, the Stripping mechanism of the weld, the mechanism of ultrasonic weld inspection and money transactions from mechanism to mechanism with automatic system, installation wyposarzenia column of fuel pellets in the open end of the shell with the mechanisms stacking and feeding shells on the equipment and removing the filled shells, the Stripping device of the open end of the filled shell, the device mounting clamps into the open end of the filled casing, a control mechanism and sorting in the internal components, installation of sealing contact butt welding stub to curb the shell under the pressure of the inert gas helium under the shell, the control mechanism and formation pressure within the fuel cladding, megaproviders element, vehicle wiring from mechanism to mechanism suitable fuel element cladding, outputs defective fuel elements and automation system, characterized in that before installing the sealing mechanism installed weighing curb fuel cladding with uniform weights and a single weighing device with vertical racks for stacking them curb the fuel cladding, which is placed between the rotary feeders filled membrane fuel cells on the vertical posts of the weighing device and removal of them when the rotation of the rotary mechanisms, the weighing mechanism is equipped with a computer and a programmable controller which carries out the stop line when the discrepancy between the weight set weight with sorting as shell, and curb shell, computer systems control units of electron-beam welding stub to the membranes provided by the findings of the control parameters on beam current, accelerating voltage, the rotation speed of the fuel element on the integrated remote with a screen displaying all parameters and control modes of welding, United into a single system and the parts of the electron beam installations.

2. The automatic production line of fuel elements under item 1, characterized in that the distance between the posts of the weighing device, eliminating the deflection and deformation of the fuel cladding is not more than 250 mm

 

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