JPH08129096A - Tool for handling the upper nozzle of a fuel assembly for a pressurized water reactor - Google Patents

Abstract

(57) [Summary] [Purpose] A handling tool that lifts and conveys the upper nozzle in water, and can be used even in deep water, facilitating in-air operation by the operator, and reducing the weight to eliminate the use of a crane. [Structure] A pair of positioning pins 10a suspended from a pair of holding body suspension ropes 10b and projecting downward from the holding body 10 are fitted into S holes of an upper nozzle. At this time, the rotating shaft 11a fitted to the vertical sleeve 10e of the holding body 10 is lowered by its own weight,
The pivoting upper pin 11c slides down on the upper taper sliding portion 10h of the vertical sleeve 10e and is locked by the lower end cut locking portion 10i. At this time, the rotary latch 11b fixed to the rotary shaft 11a. Are housed in the central opening of the upper nozzle. When the rotation locking body suspension rope 11g is lifted up, the lower pivot pin 11d slides up to the lower taper sliding portion 10j and is locked to the upper cut-in locking portion 10k.
When the 1b rotates by about 45 °, it engages with the downward locking step of the upper nozzle, and the upper nozzle can be lifted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a handling tool for submerging the upper nozzle of a spent pressurized water reactor fuel assembly in water in a pool by remote operation and transporting it to a predetermined location. Regarding improvement.

[0002]

2. Description of the Related Art Fuel assembly A for a known pressurized water reactor
Is between the upper nozzle a and the lower nozzle b as shown in FIG. 5, and the required number of control rod guide tubes (thimble tubes) c
And a large number of fuel rods d are vertically mounted in an aligned state, and a required plurality of spacers e are arranged at predetermined intervals in the longitudinal direction so that this state is maintained. It is something that is done.

However, in such a pressurized water reactor fuel assembly A, the spent fuel assembly A is used in the pool water when it is to be pulled up to a desired location and conveyed. A so-called spent fuel tool has been used as an upper nozzle handling tool, but the tool has the following problems.

That is, this is a metal long pipe provided with a fitting portion, which is a kind of tool, attached to the end of the pipe.
For this reason, not only can it be handled only when the water depth is within a certain range, but the operation of latching and locking the fitting part of the tool with respect to the upper nozzle is the metal long pipe. The upper part of the fuel tank is operated in the air, and in order to perform such an operation, since the handling tool is as heavy as 200 kg, the SFP "Spent Fuel Pit (Sent Fuel) is used.
Pit) ”cranes must be used in a suspended state, and because it is a long metal pipe as described above,
Its handling and storage will also be inconvenient. Incidentally, the above-mentioned handling tool has a complicated structure because the hooks in four directions are to be lifted after being latched and locked in the stepped cavity formed in the upper nozzle a. Even if the above is operated in the air as described above, a laborious manual operation is required.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks of the prior art, the present invention firstly discloses a known S-hole that opens upward and a central opening in the upper nozzle of a fuel assembly for a pressurized water reactor. And a stepped cavity communicating with this,
The downward locking step portion is being used effectively.
For this reason, in the handling device of the present invention, the pair of positioning pins are fitted into the S hole by being suspended by the pair of holding body suspension ropes using the wire or the like.
A rotary latch fixed to the rotary shaft is automatically housed in the central opening of the upper nozzle by its own weight.
Further, in this state, by pulling up the rotary shaft by the rotary locking body suspension rope, the rotary latch automatically and automatically rotates by 45 ° due to its own weight, and The upper nozzle can be transported by engaging with the stepped cavity of the nozzle and pressing it against the downward locking step, and lifting the rotating locking body suspension rope in this state. There is.

According to the present invention, based on the above idea and configuration, a wire or the like can be used, so that even when the upper nozzle is transported in deep water, it can be handled easily without any trouble, and the constituent members Utilizing the dead weight of
By making it possible to perform the turning operation automatically, the operator is not required to perform a troublesome operation, and the structure thereof can be simplified, and the whole is finished to be relatively lightweight. Therefore, the purpose is to be able to handle it manually without using a crane or the like.

[0007]

In order to achieve the above-mentioned object, the present invention is provided with positioning pins protruding downward and holding body suspension ropes extending upward at the left and right ends. And, a holding body having a vertical sleeve penetratingly provided in the central portion, and a rotary shaft fitted to the vertical sleeve so as to be able to move up and down and a rotary locking body suspending rope extending downward. A rotation latching body composed of a rotation latch fixed to the lower end in an orthogonal shape, and the pair of positioning pins are provided by suspending the holding body by the pair of holding body suspension ropes. The sizing holes are set so that they can be fitted into the respective S holes that are provided opposite to the diagonal corners of the upper nozzle of the pressurized water nuclear reactor fuel assembly, and the upper protrusion of the vertical sleeve is provided. Guides the turning upper pin of the rotating shaft, which descends by its own weight, to the lower end notch And an upper taper slide for rotationally displacing the rotary latch of the rotary shaft so that the rotary latch can be housed in the central opening of the upper nozzle under the state where the positioning pins are fitted in the pair of S holes. The moving part is absent, and the lower part of the vertical sleeve for turning is rotated by pulling up the turning locking body suspension rope provided on the turning shaft. The pin is guided to the upper cut-out locking portion, and the rotary latch of the rotary shaft is rotated about 45 ° from the state of being housed in the central opening, so that it is formed on the outer peripheral four sides of the upper nozzle. In the stepped hollow portion, a fuel for a pressurized water nuclear reactor is characterized in that a lower taper sliding portion that pivotally displaces so as to be freely engageable with the downward locking step portion is absent. Attempting to provide an assembly upper nozzle handling tool.

[0008]

When the handling tool according to the present invention is used, the entire handling tool is hung by the pair of holding body suspending ropes, and the pair of positioning pins of the holding body is placed on the upper nozzle in water. , The pair of S holes opened upward, and the holder is placed on the upper nozzle. At this time, since the rotary shaft fitted to the vertical sleeve that is provided through the center of the holding body is in a free state, it descends due to its own weight. The upper pin slides down while coming into contact with the upper taper sliding portion formed on the upper protruding portion of the vertical sleeve, so that the rotary shaft rotates and locks on the lower end cut locking portion. It will descend to.

Therefore, in the above-mentioned locked state, the rotation shaft does not rotate unintentionally, and moreover, the rotation latch fixed to the lower end portion of the rotation shaft at a right angle is fixed. It is preliminarily positioned to be housed in the central opening which is the axial center of the upper nozzle. Next, if the operator operates the swing locking body suspension rope to lift up the swing locking body composed of the swing shaft and the swing latch, the swinging lower body protruding from the swing shaft is used. The side pin is guided by the lower taper sliding portion formed on the lower protruding portion of the vertical sleeve and rotates about 45 °, and then, the side pin is engaged and stopped at the upper end cut locking portion.

Therefore, as described above, the rotation latch is rotated by about 45 ° and enters the stepped opening of the upper nozzle from the state of being housed in the central opening, and the rotation latch is locked. By pulling up the body suspension rope, the rotation latch presses against the downward locking stepped portion in the stepped opening, and in this state, the rotation shaft has the upper end notch engaging member of the lower pivoting pin. Since it is in a non-rotating state by locking to the stopper,
The upper nozzle can be safely lifted and the fuel assembly can be transported to the proper place.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the present invention in detail with reference to the illustrated embodiments, first, the upper nozzle a in the fuel assembly A for a pressurized water reactor will be explained. As clearly shown in FIGS. 3 and 4, the diagonal line L of the nozzle body 1 which is a quadrangular disk-shaped body.
As is known, the S holes 1b and 1b are vertically provided in the upper portions of the corners 1a and 1a, respectively, and the square-shaped central opening 1c is provided at the center of the concave and convex portions. It is recessed inside the outer peripheral portion 1d formed in a shape.

Further, in the upper nozzle a, a stepped cavity portion 1e is provided directly below the outer peripheral portion 1d so as to communicate with the central opening portion 1c, and therefore, the stepped cavity portion 1e is provided. Is provided with a downward locking step portion 1f. In the same figure, as is known, 1g indicates a water flow hole, 1h indicates a thimble hole, and 1i indicates a leaf spring.

As shown in FIG. 1, the handling tool according to the present invention comprises a holding body 10 arranged laterally and a rotation locking body 11 which is orthogonal to the holding body 10 and is rotatable by up and down movement. It is composed of two members. The holding body 10 shown in the figure is formed in an elongated rectangular plate shape, and the left and right ends thereof have
This is a positioning pin 10a, 1 which projects downwards in an orthogonal shape.
0a and holding body suspension ropes 10b and 10b formed of wires or the like and extending upward. At this time, the holding body suspension ropes 10b and 10b and the positioning pin 10
In the illustrated example, the base ends 10c and 10c of the positioning pins 10a and 10a are penetrated into the holding body 10 and the base ends 10c and 10c are not necessarily aligned with the axes of the bases 10a and 10a.
The connecting rings 10d and 10d are attached to the shaft center portions of the above, and the holding body suspension ropes 10b and 10b are connected to the connecting rings.

Further, a vertical sleeve 10e is fixedly inserted through the central portion of the holding body 10 in the longitudinal direction, so that the upper protruding portion 10f is provided on the upper side of the holding body 10 and the lower side is provided on the lower side thereof. The projecting portions 10g are respectively projected.
Then, by cutting out the upper end opening portion of the upper protruding portion 10f, the upper taper sliding portion 10h is formed so that the vertical sleeve 1
0e, which is formed so as to intersect with the axis line of 0e, is continuous with the lower end of the upper taper sliding portion 10h, opens upward, and has a lower end cut locking portion formed in the axial direction of the upper taper sliding portion 10h. 10i is formed.

The lower projecting portion 10g has a lower end opening cut symmetrically through the holding body 10 corresponding to the upper taper sliding portion 10h and the lower end cut engaging portion 10i. Thus, the lower taper sliding portion 10j and the upper end notch locking portion 10k are formed, respectively. That is, the lower taper sliding portion 10j is formed so as to intersect the axis of the vertical sleeve 10e, and is opened downward continuously from the end of the lower taper sliding portion 10j. Same as above, an upper cut-out locking portion 10k provided in the axial direction is provided. In the illustrated example, both the upper taper sliding portion 10h and the lower taper sliding portion 10j described above are formed by cutting out the V-shaped facing portions at the upper end opening and the lower end opening, respectively. Although formed, the upper and lower taper sliding portions 10h and 10j can be formed by cutting a single groove instead of the V shape.

Further, the positioning pins 10a, 10a described above are used.
Is composed of a large-diameter fitting portion 10m extending downward from the base end portion 10c, which is thin, and a small-diameter guide portion 10n protruding downward from the fitting portion 10n. Has a tapered introduction taper portion 10p.

Next, the above-mentioned rotary locking body 11 will be described in detail. As described above, the rotary shaft 11a fitted to the vertical sleeve 10e so as to be able to move up and down and the lower end of the rotary shaft 11a are orthogonal to each other. The rotary latch 11b has a flat plate shape and is fixed. An upper turning pin 11c and a lower turning pin 11d project from the rotary shaft 11a in the radial direction. In the illustrated example, each pin 1 is provided.
1c and 11d are approximately 45 to each other in the rotating direction of the rotating shaft 11a.
They are provided with a phase difference of only °, while the lower end cut engaging portion 10i and the upper end cut engaging portion 1 are provided.
0k is provided on the rotary shaft 11a at a position directly above and below. However, as will be apparent from the details described later, unlike the embodiment, the turning upper pin 11c is different.
And the lower pivot pin 11d are provided so as to project on the rotary shaft 11a so as to be positioned directly above and directly below, and the lower end cut engaging portion 1
0i and the upper end notch locking portion 10k are connected to each other by the rotary shaft 1
The holes may be drilled by being shifted by about 45 ° in the rotation direction of 1a.

Further, the above-mentioned rotary latch 11b includes:
Although it is possible to use a rectangular plate-shaped body, in the illustrated example,
From the substrate portion 11e pivotally attached to the rotating shaft 11a to the rotating shaft 11a
4 support arm portions 11 separated by about 90 ° in the radial direction
f is extended, and a rotary locking body suspension rope 11g for vertically moving the rotary shaft 11a with respect to the vertical sleeve 10e is extended upward. In the illustrated example, a rotary shaft connecting ring 11h is fixedly provided on the upper end portion of the rotary shaft 11a, and the rotary locking body suspension rope 11g is connected thereto.

Therefore, the above-mentioned handling tool can be hung by the holding body suspending ropes 10b, 10b and the rotation locking body suspending rope 11g by the above-mentioned wires or the like. At this time, the two holding body suspension ropes 10b and 10b are used to suspend the rotating shaft 11a in the central portion of the holding body 10 due to the weight of the rotation locking body 11 and the vertical sleeve. It descends within 10e.
At this time, the turning upper pin 11c of the turning shaft 11a is slidably guided by the upper taper sliding portion 10h to be locked to the lower end cut locking portion 10i. As the shaft 11a descends, it automatically rotates, and the rotation latch 11b stops at a predetermined relative position with respect to the holding body 10 and is held at that position as shown in FIG. 2 (A). Become.

The positioning pins 10a and 10a of the handling apparatus suspended as described above are fitted into the pair of S holes 1b and 1b in the upper nozzle a, and the fitting portions 10m and 1m thereof are fitted.
The holder 10 is mounted on the corners 1a, 1a of the upper nozzle a by fitting up to 0 m. At this time, the rotation latch 11b is just fitted into the central opening 1c of the upper nozzle a as described above. They will go together and be stored here.

Next, by loosening the holding body suspension cords 10b and 10b and slowly pulling up the rotation locking body suspension cord 11g, the lower pivot pin 11d of the rotary shaft 11a is lowered. Since it moves upward while slidingly contacting the taper sliding portion 10j and is locked by the upper end notch locking portion 10k, this allows the rotary shaft 1 to move.
The rotation latch 11b connected to 1a rotates about 45 ° and is stopped at the position shown in FIG. 2B.

Therefore, the four formed on the rotary latch 11b.
The individual support arm portion 11f enters the continuous stepped cavity portion 1e from the central opening portion 1c. At this time,
Further, by pulling up the rotation locking body suspension rope 11g, the support arm portion 11f engages with the downward locking step portion 1f. Since the lower pin 11d for turning is locked to the upper cut-out locking portion 10k of the dynamic latch 11b, there is no unintentional rotation, so that the upper nozzle a can be safely lifted and conveyed.

Further, when the upper nozzle a is to be unlatched, the fuel assembly A hung by the upper nozzle is placed at a predetermined position and the rotation locking body is placed. If the hanging rope 11g is loosened, the rotation locking body 1
1 descends in the vertical sleeve 10e due to its own weight. As a result, as described above, the rotating shaft 11a rotates about 45 ° and the upper turning pin 11c is locked in the lower end cut locking portion 10i. Therefore, the rotating latch 11b is provided in the stepped cavity of the upper nozzle a. 1d is removed from the central opening 1d
Returning to this position, in this state, as described above, the holding body hanging rope 10
If the holding body 10 is lifted by b and 10b, the positioning pins 10a and 10a can be pulled out from the S hole 1b of the upper nozzle a and removed from the upper nozzle a.

[0024]

Since the present invention is configured as described above, the upper nozzle can be hung by using a wire or the like, so that the upper nozzle can be handled regardless of the water depth, and the operator is troublesome with hand. It is possible to automatically perform latching, locking, and unlatching by utilizing the self-weight of the member by a simple operation such as lifting the wire and releasing the wire without performing any other operation. Further, since the structure can be simplified, the weight can be reduced, and the handling tool itself can be handled without using a crane or the like.

[Brief description of drawings]

1 shows an upper nozzle handling tool according to the present invention,
(A) is a perspective view of an unlatched state, and (B) is an inclined view of a latched state.

[Fig. 2] Same as above, showing the relative relationship between the handling tool and the upper nozzle,
(A) is an explanatory plan view of the unlatched state, and (B) is an explanatory plan view of the latched state.

FIG. 3 is a perspective view of an upper nozzle suspended by the above handling tool.

4A is a side view in which an S hole portion of the upper nozzle in FIG. 3 is cut away, and FIG. 4B is a vertical sectional front view of an outer peripheral portion of the upper nozzle.

FIG. 5 is a front view of a fuel assembly for a pressurized water reactor equipped with the upper nozzle.

[Explanation of symbols]

 A Fuel assembly for pressurized water reactor L Diagonal line a Upper nozzle 1a Corner 1b S hole 1c Central opening 1e Stepped cavity 1f Downward locking step 10 Holding body 10a Positioning pin 10b Holding body hanging rope 10e Vertical sleeve 10f Upper protruding portion 10g Lower protruding portion 10h Upper taper sliding portion 10i Lower end cut locking portion 10j Lower taper sliding portion 10k Upper end cut locking portion 11 Rotation locking body 11a Rotation shaft 11b Rotation Latch 11c Revolving upper pin 11d Revolving lower pin 11g Rotating locking body Suspended rope

Claims (1)

[Claims] 1. Right and left end portions are provided with respective positioning pins protruding downward and holding body suspension ropes extending upward, and a holding sleeve in which a vertical sleeve is penetrated is provided in a central portion. Body, a rotary shaft fitted to the vertical sleeve so as to be able to move up and down, and a rotary locking body suspending rope extending upward, and a rotary latch fixed to the lower end portion thereof in an orthogonal shape. And a pair of locating pins, wherein the pair of positioning pins are diagonal lines in the upper nozzle of the fuel assembly for a pressurized water reactor when the holder is suspended by the pair of holder suspension ropes. The S-holes, which are provided opposite to the upper corners, are set so that they can be fitted in the S-holes.
Guide the upper pin for swiveling of the rotary shaft that descends by its own weight to the lower end notch locking portion, and rotate the rotary latch of the rotary shaft,
An upper taper sliding portion that is rotationally displaced so as to be housed in the central opening of the upper nozzle is provided under the state where the positioning pins are fitted in the pair of S holes, and The lower pin for turning of the rotary shaft is guided to the upper end cut lock part by pulling up the rotary lock body suspension rope provided on the rotary shaft to the lower protruding part of the mounting sleeve. In the stepped cavity formed on the four outer peripheral sides of the upper nozzle, the rotation latch of the rotation shaft is rotated about 45 ° from the state of being housed in the central opening. A tool for handling an upper nozzle of a fuel assembly for a pressurized water reactor, characterized in that a lower taper sliding portion for rotatably displacing the downward locking step portion is absent.