JP4373760B2 - Goods collection tool - Google Patents

Description

  The present invention relates to an article recovery tool that is used in a facility under the surface of water that stores or uses nuclear fuel, and that collects articles on the bottom surface of the facility by sticking them to a weight and recovering them upward. In particular, the present invention relates to an article collection tool suitable for collecting an article on the bottom surface of a spent fuel pit of nuclear fuel from an opening above the pit.

  In an underwater facility where nuclear fuel is stored or used, when an article is dropped from the upper part of the facility, it may be necessary to remotely operate the upper part to collect the article on the bottom surface.

As an example of such a facility, a spent fuel pit that is a facility related to nuclear power generation will be described.
FIG. 1 is a perspective view of a spent fuel pit, and FIG. 2 is an explanatory side view of the spent fuel pit.

  The spent fuel pit 51 includes a pool 57, a crane 54, and the like. The pool 57 is divided into a section in which the fuel rack assembly 52 is stored and an inspection pit 53. The pool 57 is filled with water for cooling the nuclear fuel assembly and the water is constantly circulated. The depth of the pool 57 extends over a dozen meters. The spent nuclear fuel assembly 56 is stored in the fuel rack, and when there is a need for inspection or other needs, the crane 54 is used to lift the nuclear fuel assembly 56 from the rack and move it to the inspection pit. Do the work. FIG. 1A shows a state where the crane 54 is located on a section in which the fuel rack assembly 52 is housed, and FIG. 1B shows a state where the crane 54 is located on the inspection pit 53. In the figure, reference numeral 55 denotes a walkway which is a human work place for operating the crane 54 and the like.

  The spent fuel pit 51 may be used for temporary storage of new or reprocessed nuclear fuel assemblies in addition to storing spent nuclear fuel assemblies after burning in a nuclear reactor.

  When a person rides on the corridor 54 and suspends the nuclear fuel assembly, bolts, nuts, plates, wires, and the like may be dropped into the pool.

  When an article is dropped into a spent fuel pit of a nuclear power plant, it must be collected at the spent fuel pit. This is to prevent foreign substances from entering the core accompanying the subsequent movement of the nuclear fuel assembly to the core.

  It is not easy to collect this article. This must capture articles that are stationary in running water. Water also enters the article collection tool. Furthermore, since water is contaminated with radioactivity and foreign substances are also contaminated with radioactivity, it cannot be easily approached by humans. Also, the bottom of the spent fuel pit is due to a long distance from the water surface.

  The conventional methods for collecting articles can be broadly divided into a method of separating with a filter using water with a pump and separating / collecting it with a filter, and a weight with an adhesive material such as bird's rice cake or double-sided tape on the bottom. There are two types of methods of sticking and collecting.

  Since a method using a pump requires a lot of preparation, a method using a weight with an adhesive is often employed.

FIG. 3 is an explanatory diagram of a conventional article collection method.
With reference to (a), the conventional weight-type article | item collection | recovery tool 101 suspends the weight 111 which attached adhesive materials 116, such as a double-sided tape, to the bottom face with the cotton rope 131. FIG. Referring to (b), the weight 111 is lowered onto the dropped article 102 and the article is adhered with the adhesive 111. Next, as shown in (c), the article 102 is lifted together with the weight.

  In the conventional weight-type article collection tool, when the article sticks out of the bottom surface of the weight, for example, a part of the article may come into contact with the surrounding wall, and the article may fall while lifting the weight.

  Next, it is difficult to position the weight and collect it more difficult to stick / capture articles that have fallen under the rack from the outlet of the spent fuel rack (especially, articles that have fallen outside the opening of the outlet). It is.

  FIG. 4 is a diagram for explaining a method of collecting an article seated under the rack assembly with a conventional weight-type article collection tool. Each arrow in (b) to (g) indicates the moving direction of the weight.

  Referring to (a), 141 is a part of the fuel rack cell, and 142 is a water outlet provided on the bottom plate of the rack cell 141. The article 102 is seated outside the outer edge of the water outlet 142.

  In such a case, the weight 111 is first lowered until it passes through the water outlet 142 as shown in (b), and then the weight 111 is moved horizontally as shown in (c) to Position. Next, the weight 111 is lowered again as shown in (d), the article is adhered to the bottom surface thereof, and is raised as shown in (e). Furthermore, as shown in (f), the weight 111 is moved horizontally to a position where the weight 111 can pass through the flowing water port 142. Then, the weight 111 is lifted as shown in (g).

  The above operations are performed from a distance of about a dozen meters above, and in a state where the weight and the rope receive the force of running water.

  Then, this invention makes it a subject to obtain the article | item collection | recovery tool which the article | item which once adhered is hard to fall in the middle of lifting. Another object of the present invention is to obtain an article recovery tool that can easily adhere and capture articles located outside the outer edge of the through hole. Furthermore, this invention makes it a subject to obtain a goods collection tool suitable when collect | recovering the articles | goods in the bottom face of the spent fuel pit of nuclear fuel from an upper opening part.

In order to solve the above-mentioned problems, an article recovery tool according to the present invention is an article recovery tool for recovering the article by adhering the article to the bottom surface of a weight, which is used in a facility under the surface where nuclear fuel is stored or used. A weight having an adhesive surface on a bottom surface, an anti-contact member engaging with the weight and having an overhang, and a penetrating portion attached to the weight and provided in the anti-contact member. When the weight is suspended by the suspension member, the weight and the anti-contact member are engaged and integrated, and the integrated weight and the anti-contact When the member is projected onto a horizontal plane, the orthographic contour line of the weight is an article collection tool located inside a line segment connecting the orthographic projections at the tip of the overhang portion , and the article collection tool is a part of the bottom plate An article located below the bottom plate of the cylindrical body having a through hole in An article recovery tool for passing through and recovering the cylindrical body, wherein the bottom of the anti-corrosion member is convex downward and engages with a through hole in the cylindrical body bottom plate. An article collection tool characterized by the above.

  In this article collection tool, even if the weight swings during lifting, the overhanging portion of the anti-corrosion member comes into contact with a nearby wall, etc., so the outer periphery of the bottom surface of the weight inside the overhanging portion is in contact with the wall, etc. Hard to do. Therefore, it is possible to suppress a situation in which an article that adheres to the bottom end and a part of which sticks out of the bottom falls during the lifting.

  In the present invention, the protruding portion of the anti-corrosion member can be formed in a wire shape, a rod shape, a flat plate shape, or the like. Moreover, the front-end | tip part may spread. Furthermore, a plate-like member extending in a planar shape from the anti-corrosion member can be used as the anti-corrosion member. The orthographic projection onto the horizontal plane at the tip of the overhanging portion may be a point or a line. Furthermore, the overhanging portion may be attached at any position in the vertical direction of the anti-corrosion member.

  Engagement between the weight and the anti-corrosion member is such that the engaging portions of both are made substantially the same size, and one and / or both of the engaging surfaces are tapered, a sawtooth shape that engages both surfaces, It can carry out by well-known methods, such as making it uneven shape.

As the material of the weight and the anti-corrosion member, a material having a specific gravity heavier than that of water is selected. For example, iron or stainless steel can be used. The hanging member can be a rope, a wire, or the like. A well-known material can be used for an adhesive. For example, it can be realized by sticking a double-sided tape on the bottom surface of the weight, or applying a gum-like substance such as a bird rice cake. In particular, the latter is suitable for capturing a three-dimensional article .

And if it is made like this invention , the probability that the center of a touch-proof member will seat according to the center of a flowing water port will become high.

  The bottom convex shape means a shape in which the area of the imaginary plane surrounded by a cutting line cut by a plane parallel to the horizontal plane decreases toward the bottom, for example, the bottom is tapered. It means being. Accordingly, it includes a cone, a quadrangular pyramid, a polygonal pyramid, a shape obtained by removing these tip portions, and the like. Further, the inclination of the taper may be equal or different at any point on the bottom side surface. Usually, since the through-hole on the bottom surface of the cylindrical body is a flat columnar shape, it is preferable that the bottom portion is formed by removing the tip portion from the cone.

  As for the engagement state between the bottom and the through hole of the bottom plate, both may be in contact with each other, may be in contact with each other, or may be in contact with each other by discontinuous surfaces, lines, or points. For example, if the through hole has a cylindrical shape and the bottom is a shape of a part of a polygonal cone, the two come into contact at discontinuous points. If the through hole is cylindrical, it often comes in contact with a line, and if the through hole side surface is tapered, it often comes in contact with a surface or line.

  In the present embodiment, the overhanging portion also serves as a guide when the weight moves up and down inside the cylindrical body.

In one embodiment of the present invention, the article collecting device, said the anti-corrosion member engaged with said integral mass is, when leaving the top of each other, the relative horizontal position of the weight and the anti-corrosion member moves shift A moving means may be provided. According to the present embodiment, the bottom surface of the weight easily reaches the outside of the opening contour line of the cylindrical body bottom plate, and the collection of articles in such a place is facilitated.

In another embodiment of the present invention, the article recovery tool further includes the anti-contact means and the vertical movement guide means of the weight provided on the shift movement means, and the shift movement by the shift movement means. The vertical movement by the vertical movement guide means may be started from the end point.

  According to this embodiment, since the weight moves vertically from immediately before the pressure-sensitive adhesive surface of the weight contacts the article to the point of contact, the article is more reliably adhered and captured.

  In still another embodiment of the present invention, the shift moving means is attached to the anti-contact member, and the side plate located on the side surface of the weight in a state where the weight and the anti-contact member are integrated. The guide plate may be formed of a guide groove disposed on the side plate and a protrusion disposed on a side surface of the weight and engaged with the guide groove.

In this embodiment, it becomes easy to process and manufacture the displacement moving means.
In the present embodiment, the guide groove may be a guide hole penetrating the side plate or a non-penetrating groove.

  However, in the present invention, a guide groove may be provided on the weight side and a protrusion may be provided on the side plate side.

  Further, in another embodiment of the present invention, the article recovery tool is a used fuel rack in which the cylindrical body is provided in a spent fuel pit for nuclear fuel, and the article recovery tool is used for using nuclear fuel. It may be an article collection tool used for collecting foreign matter existing on the bottom surface of the spent fuel pit.

  In the present invention, the above embodiments can be combined as much as possible.

  In the article recovery tool of the present invention, a situation in which an article once adhered to the bottom surface of the weight falls while being pulled up is suppressed.

  Further, in the article recovery tool of the present invention, the anti-contact member is seated in accordance with the water outlet on the bottom surface of the cylindrical body, so that the weight can easily pass through the water outlet. Furthermore, the article recovery tool of the present invention can easily adhere and capture articles located outside the outer edge of the through hole in the cylindrical body bottom plate.

  Further, the article recovery tool of the present invention is a jig suitable for recovering an article on the bottom surface of a spent fuel pit of nuclear fuel from an upper opening.

  The article recovery tool according to the present invention will be further described below with reference to examples. The dimensions, materials, shapes, relative positions, etc. of the members and parts described in the embodiments of the present invention are not intended to limit the scope of the present invention to those unless otherwise specified. It is merely an illustrative example.

  FIG. 5 is a diagram showing the article collection tool 1. (A) is a top view, (b) front view, (c) is a side view. The article recovery tool 1 of this embodiment is used in a spent fuel pit.

  The article recovery tool 1 includes a weight 11, a touch-proof member 21, and a wire 31. In the figure, reference numeral 41 denotes a part of the fuel rack cell, which is indicated by a one-dot chain line.

  At the upper part of the anti-corrosion member 21, there is an overhanging portion 23 protruding in all directions. The tip 26 of the overhang 23 extends to the inner surface of the fuel rack cell 41 just before the position where it contacts. Further, a through portion 22 is formed in the upper central portion of the anti-corrosion member 21.

  The central portion of the anti-corrosion member 21 is cylindrical, the bottom portion 24 is processed into a taper shape, and the side surface 25 is a part of a downwardly convex cone. The side surface 25 has such a size as to be brought into surface contact with and engage with the inner surface taper processing portion 43 of the water flow port 42 formed in the bottom surface of the fuel rack cell.

  Two side plates 27 are erected on the lower part of the anti-corrosion member 21. That is, the upper portion of the side plate 27 is positioned in the through portion 22 and both are fastened with mounting bolts, whereby the anti-contact member 21 and the side plate 27 are fixed. Mounting bolts are not shown. The orthographic contour line on the horizontal plane of the side plate 27 is inside the contour line obtained by orthographically projecting the bottom 24 of the anti-corrosion member 21 on the horizontal plane.

  Two pairs of guide grooves 28 are formed in the two side plates 27. The guide groove 28 includes an oblique portion and a vertical portion 29 at the tip thereof. The guide groove 28 is a hole that penetrates the side plate 27.

  The weight 11 is a substantially rectangular parallelepiped, and its bottom surface 15 is a substantially flat surface. Double-sided tape 16 is affixed to the bottom surface 15. An eyebolt 12 is attached to the center of the upper surface of the weight 11. One end of the wire 31 is coupled to the eyebolt 12 through the through-hole 22 of the touch-proof member 21.

  Two guide pins 14 are attached to each of the two surfaces facing the side plate 27 among the four side surfaces of the weight 11. Each of the guide pins 14 is engaged with the guide groove 28. Therefore, when the weight 11 is suspended by the wire 31, the anti-corrosion member 21 is placed on the weight 11 via the protrusion 14 and the guide groove 28.

  With reference to the plan view (a), when the weight 11 and the overhanging portion 23 are orthographically projected onto a horizontal plane, the contour line of the weight 11 is inside the line segment connecting the orthographic projection of the tip 26 of the overhanging portion 23.

  FIG. 6 is an explanatory diagram for explaining a method of collecting an article located below the fuel rack cell using the article collection tool 1.

  In the figure, 2 is an article to be collected. Further, members and portions in the drawing are denoted by the same reference numerals as those described in FIG. (A)-(j) are arranged according to the time series of article collection.

  First, (a) shows the suspended state of the article recovery tool. The article collection tool 1 descends in the fuel rack cell 41. At this time, the overhang portion 26 descends while contacting or sliding with the inner surface of the fuel rack cell 41. Therefore, the weight 11 descends while passing through the approximate center of the fuel rack cell.

  (B) shows the state in which the anti-corrosion member 21 is seated on the flowing water port 42 on the bottom surface of the fuel rack cell. Since the taper shape of the side surface 25 of the anti-corrosion member 21 guides and the anti-corrosion member descends while passing through the approximate center of the fuel rack cell, as described in FIG. Positioning is performed automatically, and the seating operation is performed smoothly.

  (C) shows a state in which the weight 11 descends away from the anti-contact member 21. At this time, the weight 11 descends while the protrusion 14 slides on the oblique portion of the guide groove 28, so that the horizontal position of the weight 11 shifts. That is, the weight 11 is pushed outward from the contour line of the water flow port 42 of the fuel rack cell 41.

  (D) has shown the state which the weight 11 leaves | separates from the anti-contact member 21, and falls further. At this time, since the projection 14 is lowered by the protrusion 14 being restricted by the vertical portion 29 of the guide groove 28, the horizontal position of the weight 11 does not shift and only the vertical position changes.

  (E) shows a state where the article 2 is adhered and captured. The article 2 is adhered to and captured by the double-sided tape 16 on the bottom surface of the weight 11. As described in (d), during adhesion, the weight 11 moves vertically and approaches and contacts the article 2 from above. For this reason, the adhesion of the article 2 to the double-sided tape 16 is more reliably performed.

  (F) shows the upward movement state of the weight. Guided by the vertical portion 29 of the guide groove 28, the weight 11 moves upward.

  (G) shows the shift movement state of the weight. The weight 11 moves upward and also in the horizontal direction.

  (H) shows a state in which the weight and the anti-corrosion member are integrated. The weight 11 and the touch-proof member 21 are integrated.

  (I) shows the lifting state of the article recovery tool. The article recovery tool 1 in which the weight and the touch-proof member are integrated is lifted upward. At this time, since the weight 11 passes through the center of the inner surface of the fuel rack cell 41, even if a part of the article 2 protrudes from the bottom surface of the weight 11, the situation of falling in contact with the inner surface of the fuel rack cell is reduced. An example of the weight 11 has an outer shape of 9 cm × 5 cm × 10 cm, made of stainless steel, and has a weight of about 3 kg.

  As described above, according to the article collection tool 1, the bottom surface of the weight can easily reach the outside of the line projected on the bottom surface of the pool. Therefore, in the case of a fuel rack cell having a square cross section, if the direction is changed by 90 degrees and the operation is performed four times, the four-side bottom surface of a single fuel rack cell can be substantially scanned. For this reason, if a mark is given by means such as coloring one of the four overhang portions, the article recovery tool is more convenient to use.

  The use place of the article recovery tool is not limited to the spent fuel pit, but is suitable for a subsurface facility where nuclear fuel is stored or used.

It is a perspective view of a spent fuel pit. It is side surface explanatory drawing of a spent fuel pit. It is explanatory drawing of the conventional goods collection | recovery method. It is a figure explaining the method of collect | recovering the articles | seats sat under the rack aggregate | assembly with the conventional weight-type article | item collection | recovery tool. It is a figure of an article collection tool. It is explanatory drawing explaining the method of collect | recovering articles | goods using an article collection tool.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Goods collection | recovery tool 2 Goods 11 Weight 14 Guide pin 16 which protrudes Adhesive surface Double-sided tape 21 Anti-contact member 23 Overhang part 24 Bottom part 27 Side plate 28 Guide groove 31 Wire 41 which is a suspension member Fuel rack cell 42 which is a cylindrical body Through-hole Running water outlet

Claims (5)

An article recovery tool for collecting the article by adhering the article to the bottom surface of the weight, used in a facility under the surface of the water where nuclear fuel is stored or used,
A weight having an adhesive surface on the bottom surface;
An anti-contact member that engages with the weight and has an overhang;
A suspension member attached to the weight and extending upward through a penetrating portion provided in the anti-contact member,
When the weight is suspended by the suspension member, the weight and the anti-contact member are engaged and integrated,
When the integrated weight and the anti-corrosion member are projected onto a horizontal plane, the normal projection contour line of the weight is an article collection tool that is inside a line segment connecting the normal projection of the tip of the overhang portion ,
Furthermore, the article collection tool is an article collection tool for collecting an article positioned below the bottom plate of a cylindrical body having a through hole in a part of the bottom plate through the cylindrical body. ,
The article recovery tool , wherein a bottom portion of the anti-corrosion member is convex downward and engages with a through hole of the cylindrical body bottom plate . Wherein the anti-corrosion member engaged with said integral mass is, when leaving the top of each other, according to claim 1 Symbol the relative horizontal position of the said anti-corrosion member weight is characterized in that a shift movement means for moving Article collection tool listed. The shift movement means is further provided with the anti-contact means and the vertical movement guide means of the weight, and the vertical movement by the vertical movement guide means starts from the end point of the shift movement by the shift movement means. The article recovery tool according to claim 2 . The displacement moving means is attached to the anti-contact member, and a side plate located on a side surface of the weight in a state where the weight and the anti-contact member are integrated with each other, and a guide groove disposed on the side plate. , claim 2 or claim 3 article collecting device according to, characterized in that comprises a projection that engages the guide groove is disposed on a side surface of the weight. The cylindrical body is a spent fuel rack provided in a spent fuel pit for nuclear fuel,
The article recovery tool according to any one of claims 1 to 4 , wherein the article recovery tool is an article recovery tool used for recovering foreign matter existing on a bottom surface of a spent fuel pit of nuclear fuel.

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