Fuel element can process line

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

SUBSTANCE: proposed process line has mechanism for press-fitting bottom plug in calibrated end of can provided with cutoff gear for piece-by-piece feeding of bottom plugs of different types that incorporates bottom plug passage duct accommodating C-shaped member with reciprocating horizontal-motion actuator whose top flap has slot engageable with upper cylindrical part of bottom plug; bottom flap is longer than top one and is provided with bottom plug passage hole shifted toward edge of bottom flap; flaps are spaced apart through distance slightly longer than maximal length of thick end of bottom plug; rod designed for press-fitting bottom plug in calibrated end of can has bed with seat to receive bottom plug, maximal-size portion of seat following shape of bottom plug.

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

1 cl 7 dwg

 

The invention relates to nuclear power and may find application in the manufacture of membranes for fuel elements (FE) for a nuclear reactor. It is known that the shells TVEL imposed the most stringent requirements on their geometrical dimensions, in particular the curvature as curb fuel material and sealed fuel Rods subjected to the Assembly in the fuel Assembly (FA), and the Fuel elements with a curvature to collect in the fuel assemblies is impossible without further destruction due to the failure placed coaxially cells of the spacer grids on the length of the fuel assemblies.

Known automatic line for the production of membranes for the fuel rod containing the tilt table, along which technological sequence posted by mechanisms pieces of tubing in the size of the shell, control the length of the membrane in the form of rolling in the axial direction and fixed stops, calibration of end of the shell, baths, degreasing, rinsing, and drying of the outer and inner surfaces of the shells with the mechanisms of the rotary lever move the shells from the bath into the tub, set after the first inclined table of the second tilt table, along which technological sequence posted by mechanisms pressing the calibrated plugs in the end of the shell, weighing, installation of electron-beam welding stub to oblock is, kickers shell with each mechanism and sensors interlocked with these mechanisms (see patent 2084026 on the application 94037637/25 from 06.10.94,, publ. 10.07.97,, MKI G 21 21/02).

Automatic position line segments of the tube in the size of the shell has mechanisms for clamping the tube in the lodgement of an inclined table aligned holes in the cutting machines, however, when the sliding tube by an inclined table on the position of the pieces of tubing in the size of the shell is not excluded skewed when rolling on an inclined table tube and its placement relative to the lodgement crooked, which can lead to misalignment of the tube with the holes in the cutting machine, and moving the latter toward each other, the tube rests in the body of this or that machine and deformed, and the variances of the shell curvature for fuel element is not valid.

Automatic line for the position calibration one end of the shell also has a clamp mechanism of the shell in the lodgement coaxially from one side of the fence, and the other hole of the calibration mechanism, which when moved to calibrate the end of the shell does not preclude the timely release of the calibrated end of the shell of the clamp mechanism calibration, which can lead to deformation of the shell kickers when non-exempt end of the shell from the sizing mechanism. Deformed about the points when this goes into a fatal marriage.

Standard sensors on the line, including in the positions indicated, where uncontrolled marriage caused by actuators do not control and do not respond to axial, not provided, the movement of the tubes at the position of the segments in the shell size and position calibration. The axial displacement that occurs when hitting the body of the cutting machine at one end of the shell or the failure unclamping mechanism calibration during the return movement to the initial position, an indication that the shell is deformed and go into a marriage.

Closest to the technical essence and the achieved effect is the automatic production line of membranes for fuel cells, mainly for nuclear pressurized water reactor, containing the first tilt table, along which technological sequence posted by mechanisms pieces of tubing in the size of the shell, control the length of the membrane in the form of rolling in the axial direction and fixed stops, calibration of end of the shell, baths, degreasing, rinsing, and drying of the outer and inner surfaces of the shells with the mechanisms of the rotary lever move the shells from the bath into the tub adjacent to the baths of the second tilt table, along which technological sequence posted by mechanisms Zap is associ plugs in the calibrated end of the shell, weighing the installation of electron-beam welding the caps to the shell, kickers shell of each mechanism on the tilt table and sensors interlocked with these mechanisms, where between the sensors on the position of the pieces of tubing in the size of the shell and between the sensors on the position of the calibration one end of the shell horizontally placed sensors that interact with balances vertically mounted support rollers with grooves for forming interacting with the shell, where each counterweight is made of metal equal to the diameter of the horizontal sensor, body support roller is made of a polymeric material, and each horizontal sensor is electrically connected to an electric circuit disconnect mechanisms pieces of tubing in the size of the shell and calibration one end of the shell off at offset around the axis of the support roller and the deviation of the counterweight support roller from the axis of the horizontal sensor (see Russian Federation patent RU 2170463 from 29.06.1999,, publ. 20.07.2001, IPC 7 G 21 C 21/02 “the Automatic production line of fuel cladding”).

This embodiment of the sensor will allow axial displacement of the shell, and even with a slight rotation of the support roller and a slight shift of the counterweight support roller relative to the horizontal sensor immediately about the involved installation of tube lengths in the size of the shell and a calibration mechanism, thus preventing bending (deformation) of the shell, and return with the counterweight support roller to its original position.

Automatic line-similar to a patent 2084026 and automatic line-a prototype for the patent 2170463 provides for the manufacture of membranes for fuel rod the same size. However, there is an operational need production on one line shell for the fuel elements of different sizes, VVER-1000 model 0401, VVER-1000 model 493, VVER-440, which differ from each other (VVER 440 from VVER-1000) in length, and the length of the bottom plugs. If the length of the lower plug for TVEL VVER-440 is 32 mm-039the length of the lower plugs for Fuel of VVER-1000 ranges from 40±0.3 mm to 45±0,3 mm Naturally need to change devices on automatic line feeding the bottom plugs in accordance with the size of the pressing them into the shell before the electron-beam welding to each other.

An object of the invention is the expansion of technological capabilities of automatic lines and jackets TVEL different sizes on the same line.

This technical problem is solved in that in the automatic production of membranes for fuel elements containing mechanisms pieces of tubing in the size of the shell, control the length of the shell, the calibration end of the shell, baths, degreasing,rinsing, and drying shell, mechanisms pressing the bottom of the calibrated plugs in the end of the shell, weighing and installation of electron-beam welding the lower plug to the shell, according to the invention the mechanism for pressing the bottom of the calibrated plugs in the end of the shell is equipped with a shut-off valve single-piece feed of the bottom plugs of different sizes on the injection in the calibrated end of the shell made of the wiring channel of the lower plugs and placed in it-shaped element with the drive of a reciprocating horizontal movement, in which the upper flap provided with a groove communicating with the cylindrical upper part of the lower plug, the bottom flap is made with a length greater than the length of the top flap, and has shifted to the edge of the bottom valve hole wiring lower plug, damper placed apart at a distance slightly greater maximum length of the thickened portion of the lower bracket, and the rod pressing the bottom of the calibrated plugs in the end of the shell is made with lodgement laying lower plug with the socket, repeating the bottom cap on the maximum size.

This embodiment of the mechanism pulling the plugs in the calibrated end of the shell will allow you to solve the technical problem and to produce casings for different sizes of theprovides the operating elements with plugs of different sizes without having to reconfigure the pressing mechanism.

The drawings show:

Figure 1 - the automatic production line of fuel cladding;

Figure 2 - mechanism of pressing the lower plug into the shell;

Figure 3 - the mechanism of pressing the bottom of the insert membrane (cut);

Figure 4 - stock;

5 is a-shaped element;

6 is a support roller with a sensor;

Fig.7 - support roller.

The automatic production line of membranes for fuel cells primarily for nuclear reactor VVER-type contains the first tilt table 1, along which technological sequence posted by mechanisms 2 pieces of tubing in the size of the shell 3, control the length of the shell 3 in the form of rolling 4 in the axial direction and fixed 5 stops, calibration 6 one end of the shell 3, 7 baths degreasing, rinsing, and drying of the inner and outer surfaces of the shell 3 with the mechanisms of the rotary lever move the shells from the bath into the tub (not shown), the second adjoining baths 7, the tilt table 8, along which technological sequence posted by mechanisms pressing 9 stub 10 in the calibrated end of the shell 3, weighing 11, 12 installation electron beam welding stub 10 to the shell 3, kickers 13 shell 3 with each mechanism on the tilt table and the sensors 14 interlocked with these mechanisms is AMI.

Mechanisms 2 are made with the possibility of axial movement towards each other, and axial rotation.

Mechanism 6 calibration performed with move-hitting at the end of the shell 3.

Between the sensors 14 to position the segments of the tube in the size of the shell 3 and between the sensors 14 at the position calibration 6 one end of the shell 3 horizontally placed sensors 15, interacting with a counterweight 16 is vertically installed the support roller 17 with the groove for forming interacting with the shell 3, where the counterweight 16 is made of metal equal to the diameter of the horizontal sensor 15 and the body support roller 17 is made of polymeric material. Horizontal sensor 15 is electrically connected with an electric circuit disconnect mechanisms 2 pieces of tubing in the size of the shell and calibration 6 one end of the shell 3, interruptible at offset around the axis of the support roller 17 from the horizontal axis of the sensor 15. On the positions of the segments 2, 6 calibration, pressing 9 automatic mounting shell 3 to the inclined tables (not shown).

The pressing mechanism 9 lower plug 10 in the calibrated end of the shell 3 is equipped with a shut-off valve 18 single-piece feed of the lower plugs 10 different sizes for pressing the calibrated end of the shell 3 made of channel 19 wiring the bottom of the plugs 10 and placed in it -shaped element 20 with the actuator 21 of the reciprocating horizontal movement, in which the upper flap 22 is provided with a groove 23 that communicates with a cylindrical upper part 24 of the lower stub 10. The bottom flap 25 is made with a length greater than the length of the top flap 22 and is provided with offset to the edge of the bottom valve hole 25 26 wiring the lower plug 10. Valves 22, 25 are placed apart at a distance “L” several large maximum length L1” thickened portion of the lower stub 10 L>L1. The stem fitting 27 of the pressing mechanism 9 lower plug 10 in the calibrated end of the shell 3 is made with the lodgement 28 laying lower plug 10 with the socket 29, repeating the bottom plug on its maximum size.

The automatic production line of fuel cladding works as follows.

On the first inclined table 1, the tube is rolled to the position of the pieces of tubing in the size of the shell 3, where with the help of mechanisms 2 segments, moving towards each other, staying at a specified distance, and the tube is cut in the size of the shell 3.

The kickers 13 by the signal of the sensor 14, the shell 3 is discharged from the cutting position on the tilt table 1, which rolls on the testing length, where with the help of a rolling stop 4 and the fixed stop 5 is smiryaetsya length sheath 3.

The kickers 13 by the signal of the sensor casing 3 is discharged from the position monitoring length on the tilt table, which is rolled to a position 6 calibration one end of the shell 3, which uses the mechanism 6, which is moved to calibrate the end of the shell 3, and calibrate one end of the shell 3.

The signal sensors 14 kickers 13 shell 3 is discharged onto an inclined table 1, which moves in the bath 7, where the inner and outer surfaces of the membrane are subjected to degreasing, washing and drying.

From baths 7 shell 3 is supplied to the second tilt table 8, moves it to the position of the pressing 9 stub 10 in the calibrated end of the shell 3. The kickers 13 shell with the cap is reset to the second tilt table 8, is fed to the position of the weighing 11 and the welding stub 10 to the shell 3 by electron-beam installation 12.

On the position of the segments 2 of the tubes 3 in the shell size and position calibration 6 provides automatic shutdown of the installations with horizontal sensor 15 that interacts with the counterweight 16 and the support roller 17.

In the case when the actuators fail in the work, for example the tube at the position of the segments formed by warp and one end abutted against the housing netaudio body of the cutting machine 2, then at the slightest shift around its the th axis of the support roller 17 as a result of movement of the tube, lying in the groove of the support roller 17, and the displacement of the counterweight 16 relative to the horizontal sensor 15 last gives the signal to shut off mechanism 2 segments. Similarly, the horizontal sensor 15 on the position of the calibration in the absence of the calibrated end of the shell 3 of the mechanism 6 calibration gives a signal to disable the calibration mechanism.

Thus, even when the deviation in the Executive machinery of the line translation in marriage shells excluded.

Automatic line production of membranes with 3 plugs of different sizes for VVER-440, VVER-1000 models 493 and 401 without reconfiguration of the pressing mechanism 9 of the lower plugs 10 in the shell 3.

When the lower plug 10 through the wiring channel 19 are received in the clipper 18 piece filing the bottom of the plugs 10 for pressing them into the shell 3.

-shaped element 20 of the cutter 18 is in constant reciprocating horizontal movement with the actuator 21.

The lower cover 10 located on the bottom of the valve 25, the motion-shaped element 20 is left of its cylindrical upper part 24 in the groove 23 of the upper flap 22, and the lower thickened portion of the lower plug 10 when matching hole 26 falls and the wiring channel enters the lodgement 28 of the rod 27, with DV the position which the bottom cover its cylindrical upper part 24 is in the slot 29 and zapressovyvajutsja thickened part of the shell 3. The wiring channel 19 of the next lower cap 10 receives the thickened part of the upper flap 22-shaped element 20, the motion which the right bottom cap 10 falls vertically on the bottom of the valve 25. As the movement-shaped element 20 with matching holes 26 with the lower cover 10 of the latter is fed to the injection into the shell 3 and the cycle repeats. Due to the fact that the flap 22, 25 are placed apart at a distance “L”, which is somewhat greater than the length “L1” of the thickened portion of the lower stub 10, single-piece flow for pressing the bottom of the plugs 10, you can make any size regardless of the length of the cylindrical upper portion 24. Tests confirmed the positive characteristics of the line.

The automatic production line of membranes for fuel elements containing mechanisms pieces of tubing in the size of the shell, control the length of the shell, the calibration end of the shell, baths, degreasing, rinsing, and drying of the membranes, mechanisms of pressing the bottom of the calibrated plugs in the end of the shell, weighing, installation of electron-beam welding the lower plug to the shell, characterized in that the mechanism for pressing the bottom of the calibrated plugs in the end of the shell is equipped with a shut-off valve single-piece feed the bottom for the of losec different sizes for pressing the calibrated end of the shell, made of the wiring channel of the lower plugs and placed in it a C-shaped element with the drive of a reciprocating horizontal movement, in which the upper flap provided with a groove communicating with the cylindrical upper part of the lower plug, the bottom flap is made longer than the length of the top flap and provided with offset to the edge of the bottom valve hole wiring lower plug, damper placed apart at a distance slightly greater maximum length of the thickened portion of the lower bracket, and the rod pressing the bottom of the calibrated plugs in the end of the shell is made with lodgement laying lower plug with the socket, repeating the bottom cap on the maximum size.



 

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