JPH0120719Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a cleaning device for fuel rods for a nuclear reactor.

For example, a nuclear reactor is loaded with fuel assemblies. As shown in Fig. 1, this fuel assembly consists of an upper nozzle 1 and a lower nozzle 2 which are vertically spaced apart and arranged in parallel, and a lattice-shaped nozzle arranged at a predetermined interval between them. A plurality of support grids 3 are inserted and supported at predetermined intervals in the grid spaces of the support grids 3, and the upper and lower ends are connected to the upper nozzle 1 and the lower nozzle 2, respectively, thereby forming the framework of the fuel assembly. a control rod guide tube 4, which is inserted into a predetermined lattice space of the support lattice 3, is elastically supported, and a plurality of fuel rods in which a large number of fuel pellets 6 and springs 7 are hermetically sealed in a cladding tube 5; It consists of 8.

By the way, a traceability label 9 is attached to this fuel rod 8 as shown in FIG.
A unique number for each fuel rod 8 is written on the traceability label 9 so that the production and inspection history of the fuel rod 8 can be traced. Therefore, when a fuel rod 8 that has passed inspection is inserted into the lattice space of the support lattice 3 to assemble a fuel assembly, the traceability label 9 remains attached to the surface of the fuel rod 8 after being peeled off. To remove the glue,
Not only the parts to which this glue has adhered, but also the entire fuel rod 8 must be cleaned one by one using acetone and gauze.

However, in the past, this cleaning work was done manually, which resulted in workers harming their health by inhaling acetone gas, and requiring a lot of manpower.
Furthermore, since acetone is easily flammable, it has been necessary to take fire prevention measures, so there has been a desire for a significant improvement in this process.

This idea was made in view of the above circumstances,
The upper and lower pads, which are vertically movable and facing each other inside the case, are impregnated with cleaning liquid from a liquid supply tank, and the fuel is inserted between the upper and lower pads via the rod guide drive roller and driven roller. By holding the rod between the upper and lower pads, rotating it using a driving roller and a driven roller, and discharging it out of the case, the glue adhering to the fuel rod after the traceability label has been removed is automatically removed. This allows for significant labor savings and cost reductions, protects the health of workers, and prevents uneven work, improving the quality of fuel rods. The purpose is to provide a fuel rod cleaning device that can measure the

An embodiment of this invention will be described below with reference to FIGS. 3 to 6. 11 in the figure is a case,
This case 11 includes a bottom plate 12, a top plate 13, and a side plate 1.
4, 14, 15, and 15 are formed into a box shape. The top plate 13 extends outward from the side plates 14, 14, and the side plates 15, 15 are transparent plates.

Above the top plate 13 is a column 1 as shown in FIG.
A liquid supply tank 18 is provided via 6, 16 and a support plate 17.

A bearing 19 is fitted and attached to the center portion of the top plate 13 in the left-right direction in FIG. 4, and a shaft 20 is fitted into the bearing 19 so as to be vertically slidable. Also, on the top plate 13, there is a bearing 1 as shown in FIG.
Bearing 2
1 and 22 are fitted and attached. Shafts 23 and 24 are fitted into these bearings 21 and 22 so as to be vertically slidable. A support plate 25 is horizontally attached to the upper ends of the shafts 23 and 24. A cylinder mechanism 26 is attached to the center of the support plate 25, and its piston rod 27 passes through the support plate 25 and is vertically movable. The upper end of the shaft 20 is connected to the tip of the piston rod 27.

Also, inside the case 11 is a rectangular upper pad 2.
8. The lower pads 29 are arranged horizontally and facing each other. The upper pad 28 is attached at its center to the shaft 20 and is movable up and down. The upper pad 28 also has a recess 3 formed on its lower surface.
It has a felt (liquid-containing member) 31 that is fitted and attached to the 0. Further, a communication hole 32 that opens into the recess 30 is formed in the upper pad 28 . This communication hole 32 is communicated with the inside of the liquid supply tank 18 via a vinyl conduit 33 and a pipe 34. Through holes are formed at two corners of the upper pad 28, and the lower ends of the shafts 23, 24 are loosely inserted into these through holes.

The lower pad 29 has its two corners attached to the axes 23 and 24.
It is attached to the lower end of the pad and can be moved toward and away from the upper pad 28 by actuation of the cylinder mechanism 26. The lower pad 29 has a felt (liquid-containing member) 31 fitted into a recess 35 formed on its upper surface. Further, a communication hole 36 that opens into the recess 35 is formed in the lower pad 29 . This communication hole 36 is made of vinyl conduit 3.
7. Communicates with the inside of the liquid supply tank 18 via the tank 38. Then, the cylinder mechanism 26, the shaft 2
0, 23, 24, vertical movement mechanism 3 by support plate 25
9 are configured.

Further, as shown in FIG. 5, case 1 is located on one side of upper pad 28 and lower pad 29, respectively.
1 is provided with brackets 40 and 41. These brackets 40 and 41 have shafts 42 and 41, respectively.
43 is rotatably attached, and cotton bands 44, 45 are removably wound around the shafts 42, 43, respectively, forming cotton band wrapping rolls 44a, 45a.

A bracket 46 is provided within the case 11 on the other side of the upper pad 28 and the lower pad 29. Winding rollers 47, 48, 49, and 50 are rotatably attached to the bracket 46 and are placed close to each other. Further, above the bracket 46, there is a bracket 5 attached to the case 11.
A tension roller 52 is rotatably attached to 1. The cotton bands 44 and 45 pulled out from the cotton band winding rolls 44a and 45a are respectively attached to the upper pad 2.
8. Attach these felts 31, 3 to the lower pad 29.
1, the cotton belt 44 is wound around the tension roller 52, and the cotton belt 44 is wound around the tension roller 52,
48, and these winding rollers 47, 48
is held by. The cotton strip 45 is passed between winding rollers 49 and 50.
9,50. Note that 53 is a holding member. Winding rollers 47, 48, 49,
A winding handle is attached to each of the winding handles 50.

Further, as shown in FIG. 4, a hole is formed in the approximate center of each of the side plates 14, 14, and flanged cylindrical rod guides 54, 54 are fitted into the holes and attached. In addition, the side plates 14, 14
Frame-shaped brackets 55, 55 are provided in a state that protrudes outward from the case 11 and is open at the bottom. Drop plate 5 of brackets 55, 55
Rod guides 57 and 57 having the same shape and size as the rod guide 54 are fitted and attached to the rods 6 and 56, respectively. Rod guide 54, 54, 5
7 and 57 are located on the same horizontal axis. The inner diameter of the rod guides 54, 54, 57, 57 is slightly larger than the outer diameter of the fuel rod.

Further, U-shaped stoppers (control mechanisms) 58, 58, 7 are provided on the inner surfaces of the side plates 14, 14 of the case 11.
7,77 is attached. Stoppa 58,
The upper surface of the rod guide 58 is substantially aligned with the top of the inner peripheral surface of the rod guides 54 and 57.

Drive motors 60, 60 are horizontally attached to both ends of the top plate 13 of the case 11 in the left and right direction in FIG. 4 via brackets 59, 59. The drive motors 60, 60 are provided so that their rotating shaft directions coincide with a center line R forming a predetermined angle θ with a reference line S shown in FIG. Pulleys 61, 6 are provided at the ends of the rotating shafts of the drive motors 60, 60.
1 is attached.

On the other hand, brackets 62, 62 are attached to the lower surfaces of the upper plates of the brackets 55, 55, as shown in FIG. 4, and drive rollers 63, 63 are rotatably attached to these brackets 62, 62. Rotating shafts 65, 6 of drive rollers 63, 63
5 passes through brackets 62, 62, and pulleys 6 are provided at the ends of these rotating shafts 65, 65, respectively.
belts 64, 6 are attached to these pulleys 65a and the pulleys 61, 61, respectively.
4 is wound. The drive rollers 63, 63 connect their rotating shafts 65, 65 to drive motors 60, 60.
The rod guides 54 and 57 are oriented in the same direction as the rotation axis of the rod guides 54 and 57, and are located directly above the center axes of the rod guides 54 and 57. Further, the lowermost ends of the outer peripheral surfaces of the drive rollers 63, 63 are aligned with the uppermost ends of the inner peripheral surfaces of the rod guides 54, 54, 57, 57. The left and right drive rollers 63, 63 in FIG. 4 are configured to rotate and stop synchronously at the same rotation speed by drive motors 60, 60 that rotate synchronously. In addition, 62a in FIG. 6 is a cover.

Also, the hanging plates 66, 66 of the brackets 55, 55
Support plates 67, 67 are attached to the brackets 55, 55 via bolts 68 screwed into them so as to be vertically movable by a predetermined amount. A groove 70 having tapered side wall surfaces 69, 69 is formed in the support plate 67, as shown in FIG. Brackets 71, 71 are attached to the side wall surfaces 69, 69, respectively. Driven rollers (pressing members) 72, 72 are connected to shafts 73, 73 on the brackets 71, 71, respectively.
It is rotatably attached via the Rotating shaft 65 of drive roller 63 and driven rollers 72, 72
As shown in FIG.
5 is oriented in the same direction as the center line R, and the axis 7
3 and 73, the cylinder mechanism 75 is arranged at an angle θ inclined with respect to the axial direction of the cylinder mechanism 75 as shown in FIG. ing.

Also, as shown in FIG. 4, a side plate 1 is attached to the case 11.
L-shaped members 74, 74 are attached to the lower portions of 4, 14, and cylinder mechanisms 75, 75 are attached vertically to these L-shaped members 74, 74, respectively. The support plates 67 are attached to the tips of the piston rods of the cylinder mechanisms 75, 75, and the support plates 67, 67 move up and down due to the operation of the cylinder mechanisms 75, 75.
2, 72 are designed to move up and down. As a result, the driven rollers 72, 72 are driven by the driving roller 6.
3. The fuel rod 8 inserted between the driven rollers 72 and 72 can be pressed against the outer peripheral surface of the drive roller 63. In addition, Figures 3 to 5
In the figure, 76 is an exhaust port.

Next, the operation of the fuel rod cleaning device configured as described above will be explained.

Before starting cleaning, the cylinder mechanism 26 is contracted and the upper and lower pads 28, 29 are in a state where they are spaced apart from each other. The vertical movement mechanism 39 and the vertical pads 28 and 29 are moving downward under their own weight, and the lower surface of the lower pad 29 comes into contact with the stopper 77 and stops, and the entire body is supported by the stopper 77. It has become a state. In addition, the cylinder mechanisms 75, 75 are also reduced in size, and the driven rollers 72,
72 is in a lowered state. Furthermore, the liquid supply tank 18 is filled with acetone (cleaning liquid), and the tanks 34 and 38 are closed.

(1) When the pots 34 and 38 are opened, acetone flows from the liquid supply tank 18 to the conduits 33 and 37 and the communication holes 32 and 3.
6 to the felt 31 of the upper pad 28 and lower pad 29 and impregnated therewith.

(2) When the take-up handle is turned, the take-up roller 47,
48 and between the winding rollers 49 and 50.
4, 45 are sandwiched, so these cotton belts 4
4 and 45 are pulled out from the cotton band winding rolls 44a and 45a and wound up, and the cotton band 4 is wrapped around the felt 31.
New unused parts 4 and 45 come into contact, and these parts are impregnated with acetone from the felt 31.

(3) The fuel rod 8 to be cleaned, with the traceability label removed and the glue still attached, is removed from the right side of the rightmost rod guide 57 in FIG.
4, and the tip of the fuel rod is positioned between the edges of cotton bands 44 and 45 wrapped around the upper pad 28 and lower pad 29.

(4) The cylinder mechanism 26 is extended. Then, the upper and lower pads 28, 29 connected to the shafts 20, 23, 24 approach each other, but in this case,
Since a downward force is applied to the shafts 23 and 24 due to the weight of the vertical movement mechanism 39 and the vertical pads 28 and 29, the shaft 20 is lowered while the shafts 23 and 24 remain in the same position. As a result, the upper pad 28 descends and comes into contact with the stopper 58,
A cotton band 44 under the upper pad 28 abuts the upper surface of the fuel rod 8. As a result, the entire vertical movement mechanism 39, vertical pads 28, 29, etc. are moved to the stopper 5.
8 is in a state where it is supported. Since the cylinder mechanism 26 continues to extend in this state, the support plate 25 rises, and the lower pad 29 rises via the shafts 23 and 24, and the felt 3
The cotton band 45 on the fuel rod 1 comes into contact with the lower surface of the fuel rod and stops.

(5) After operating the drive motors 60, 60, extend the cylinder mechanisms 75, 75. Then, the drive rollers 63, 63 rotate, and the support plate 6
7, the driven rollers 72, 72, 72, 72 rise together with the driven rollers 72, 72, 72, 72 (when the driven roller 72 reaches a predetermined position, the cylinder mechanisms 75, 75 stop). 4, the fuel rod is held between the drive roller 63 on the right side in FIG. 4 and the driven rollers 72, 72, and the drive roller 6
3, the fuel rod is rotated and transferred in the direction of arrow A in FIG. As a result, the fuel rods are rotated between the upper pad 28 and the lower pad 2.
9 acetone impregnated felt 31, 31
It passes between the upper pad 28 and the lower pad 29 while its outer circumferential surface is cleaned between the pad and the cotton bands 44 and 45.

(6) When the tip of the fuel rod reaches between the driving roller 63 and the driven rollers 72 and 72 on the left side in Fig. 4,
The fuel rod is rotated by the drive roller 63 on the left side as before and is still moved in the direction of arrow A in FIG. 4, so that it is inserted into the rod guide 57 on the left side in FIG.

(7) When the rear end of the fuel rod passes under the drive roller 63 on the right side in FIG. Once the fuel rod passes under the drive roller 63, the rotational transfer of the fuel rod ceases, so the fuel rod is manually taken out from the rod guide 57.

(8) Stop the rotation of the drive motors 60, 60, and reduce the cylinder mechanisms 75, 75. Then, the driven rollers 72, 7 pass through the support plates 67, 67.
2, 72, 72 descends. Further, the cylinder mechanism 26 is operated to contract. Then, the upper and lower pads 28 and 29 try to separate from each other, but in this case as well, the vertical movement mechanism 39 and the upper and lower pads 28 and
Since a downward force is acting due to the weight of the shaft 29, etc., the shaft 23,
24 descends. As a result, the lower pad 29 descends and its lower surface abuts against the stopper 77.
As a result, the vertical movement mechanism 39, the vertical pads 28, 29, etc. are all supported by the stopper 77. Since the cylinder mechanism 26 continues to contract in this state, the upper pad 28
rises, stops at a predetermined position, and returns to the initial state.

(9) Thereafter, the operations described in (2) to (8) above are repeated to clean a plurality of fuel rods, and after completing this operation, the pots 34 and 38 are closed to stop the supply of acetone.

In the above embodiment, the fuel rods were pressed against the drive roller 63 via the driven roller 72 during rotational transfer of the fuel rod, but the invention is not limited to this. For example, a ball may be provided in place of the driven roller 72. , the fuel rod may be configured to be pressed against the drive roller 63 via this ball.

As explained above, according to this invention, the upper and lower pads, which are vertically movable and facing each other in the case, are impregnated with cleaning liquid from the liquid supply tank, and the cleaning liquid is applied via the rod guide, drive roller, and driven roller. The fuel rod inserted between the upper and lower pads is then held between the upper and lower pads, and the traceability label is removed by transporting the fuel rod while rotating it using a driving roller and a driven roller and ejecting it from the case. Glue adhering to the fuel rods is automatically cleaned, which saves labor, resulting in significant cost reductions, and prevents workers from inhaling acetone. This has effects such as being able to protect the health of workers, preventing uneven work, and improving the quality of fuel rods.

[Brief explanation of drawings]

Fig. 1 is a partially cutaway side view of the fuel assembly, Fig. 2 is an external view of the fuel rod, Fig. 3 is a partially omitted plan view showing an embodiment of this invention, and Fig. 4 is partially omitted. 5 is a partially cutaway sectional view thereof, and FIG. 6 is a partially omitted sectional view taken along the line - in FIG. 3. 11... Case, 18... Liquid supply tank, 28...
...Upper pad, 29...Lower pad, 31...Felt (liquid-containing member), 39...Vertical movement mechanism, 44, 4
5... Cotton obi, 44a, 45a... Cotton obi winding roll,
47, 48, 49, 50... Winding roller, 5
4, 57... Rod guide, 58, 77... Stopper (control mechanism), 60... Drive motor, 63...
...Drive roller, 72...Followed roller (pressing member).

Claims (1)

[Scope of utility model registration request] a case, an upper pad and a lower pad each having a flexible liquid-containing member on opposing surfaces and vertically opposing and movably provided in the case;
A vertical movement mechanism provided in the case and for vertically moving the upper pad and the lower pad, respectively; a control mechanism provided in the case for stopping the upper pad at a predetermined position; and a control mechanism provided in the case and penetrating the case. a rod guide that guides a fuel rod between the upper pad and the lower pad, and guides the fuel rod through the case and out of the case; , a liquid supply tank that supplies liquid to both liquid-containing members of the lower pad, and a liquid supply tank located near both side walls of the case that intersect with the axis of the fuel rod, so that the upper pad is at a lowering limit position. The upper pad is rotatably attached to the case so that the lowest part of the outer peripheral surface thereof is located at approximately the same height as the lower surface of the liquid-containing member of the upper pad, and the axis of the upper pad is inclined with respect to the axis of the fuel rod. an attached drive roller; a drive motor connected to these drive rollers and provided in the case; and a drive motor provided below both of the drive rollers at the same height, and between itself and the drive roller. A fuel rod cleaning device comprising a plurality of pressing members that press the fuel rods against the drive roller by allowing rotation and movement of the fuel rods inserted into the drive roller.