JP2563427B2 - Channel fastener desorption device and channel fastener storage container - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a channel for attaching and detaching a channel fastener that connects a fuel assembly and a channel box that covers the fuel assembly in a boiling water nuclear power plant. The present invention relates to a fastener attaching / detaching device and a channel fastener storage container.

(Prior Art) A fuel assembly of a reactor of a boiling water nuclear power plant is covered with a channel box from above. The channel box is fastened and fixed to the fuel assembly by the channel fastener.

Generally, at the time of periodic inspection, inspection of irradiated fuel assembly, or reprocessing of spent fuel assembly, work for removing the channel box from the fuel assembly is performed.

Next, an operation for removing the channel box will be described with reference to FIGS.

First, as shown in FIGS. 6 and 7, the fuel assembly 2 with the channel box is fed from the inside of the reactor 40 to the fuel storage rack 5 in the fuel pool 41 adjacent to the reactor 40 via the reactor well 39. Move inside. Next, the fuel assembly 2 with the channel box is set in the channel box remover 42 provided on the wall surface of the fuel storage pool 41. In this channel box remover 42, a worker 43 loosens and removes the channel fastener using a bolt wrench 44. Next, the channel box 4 is removed from the fuel assembly 2. The movement of these fuel assemblies 2 is performed by the fuel pool 41.
This is done by the refueling machine 38 located above.

FIG. 8 shows the fuel assembly 2 and the channel box 4 covering the fuel assembly 2. As shown in FIG. 8, the fuel assembly 2 is configured by arranging a large number of fuel rods 2a, and the fuel handle 3 and four studs 8 are attached to the upper end portion of the fuel assembly 2. The fuel assembly 2 is covered with a channel box 4 from above, and is fastened and fixed by a channel fastener 6. That is, the channel fastener 6 is provided with a bolt 7, and by mounting the bolt 7 on the stud 8 of the fuel assembly 2, the channel fastener 6 fixes the channel box 4 from the outside.

(Problems to be Solved by the Invention) As described above, the fuel assembly 2 with the channel box is provided.
Are stored in the one-side fuel storage rack 5, and then the channel fasteners 6 are removed by a worker in the channel box remover 42. Then, the channel box 4 is removed from the fuel assembly 2, and these are replaced by the fuel exchanger 38.
Are separately returned to the fuel storage rack 5 and stored in separate predetermined locations.

This removal work is performed by the worker for each fuel assembly 2. Also, for example, in a new boiling water nuclear power plant, about 200 fuel assemblies 2
I am doing about. Therefore, there is a problem that it takes a long time to remove the channel box.

In such a case, if the channel fastener 6 can be removed in the storage rack 5 independently of the operator, the channel box can be easily removed from the fuel assembly, which is convenient.

The present invention has been made in view of the above points, and an object thereof is to provide a channel fastener attaching / detaching device and a channel fastener accommodating container capable of easily and easily removing the channel box from the fuel assembly with the channel box. And

[Structure of Invention]

(Means for Solving the Problem) The present invention relates to a device main body in which a lower end portion is attached to a fuel handle of a fuel assembly, a vertical drive mechanism provided on a side of the device main body, and a vertical drive mechanism of the vertical drive mechanism. A fastener holding mechanism provided at a lower end and having a rotatable bolt engaging portion that engages a bolt of a channel fastener at a lower end thereof, and the vertical drive mechanism is provided on the main body of the apparatus through a pivot shaft and is attached to the pivot shaft. The fastener holding mechanism has a drive cylinder that is rotated by a fixed rotation motor, and a shaft that extends downward from the drive cylinder, and the fastener holding mechanism has a protrusion that slides outward along a groove of the apparatus main body. A holding body connected to a shaft, a rotation motor for rotating the engaging portion, and a holding body provided in the holding body connected to the rotation motor for loosening or tightening rotation of a bolt. A channel fastener attaching / detaching device having an absorption cylinder that absorbs the stroke of a bolt that moves in the vertical direction with the above, a container main body that houses the channel fastener, and a fuel provided on the upper end of the container main body. A channel fastener storage container comprising a fixing jig engaged with an upper end of a storage rack, and a guide formed in a pyramid shape at a lower end portion of the container body.

(Operation) By driving the turning motor, the drive cylinder can be turned about the turning axis, and by driving the drive cylinder, the shaft can be moved up and down. The fastener holding mechanism can be lowered by swinging the drive cylinder around the swing axis by the swing motor and lowering the shaft by the drive cylinder. In this case, by engaging the protrusion provided on the holding body of the fastener holding mechanism with the groove portion of the main body of the apparatus whose lower end portion engages with the fuel handle, the fastener holding mechanism can be guided to just above the desired bolt. Therefore, the bolt engaging portion can be easily engaged with a desired bolt. In addition, the rotation motor of the fastener holding mechanism can be driven to loosen or tighten the bolts with the bolt engagement parts, and the stroke of the bolts that move vertically due to loosening or tightening rotation of the bolts can be absorbed by the absorption cylinder. You can

After loosening the bolts with the bolt engaging parts, remove the channel fasteners. The removed channel fastener is put into the inside from above the container body of the channel fastener storage container.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a view showing an embodiment of a channel fastener attaching / detaching device according to the present invention, FIG. 2 is a detailed view thereof, and FIG. 3 is a view showing its operation.

In FIG. 1, the channel fastener attaching / detaching device includes a device body 10 suspended from a hoist 9 of a fuel exchanger 38. A guide for engaging the fuel handle 3 of the fuel assembly 2 in the fuel storage rack 5 is provided at the lower end of the device body 10.
10a is formed.

The fuel assembly 2 is covered with a channel box 4, and the channel box 4 is fastened and fixed by attaching a bolt 7 of a channel fastener 6 to a stud 8 of the fuel assembly 2.

An air cylinder (driving cylinder) 14 constituting a vertical drive mechanism is rotatably provided on the side of the apparatus body 10 via a turning shaft 11 provided in the apparatus body 10. The turning shaft 11 is rotationally driven by a turning motor 13 via a torque guard 12. The torque guard 12 protects the turning motor 13 from overload.

A fastener holding mechanism 22 is provided below the air cylinder 14 via a shaft 15 so as to be vertically movable. The fastener holding mechanism 22 includes a holding body 23 and an air cylinder (absorption cylinder) 24 provided in the holding pair 23.

Next, the details of the fastener holding mechanism 22 will be described with reference to FIG.

A cylinder 29 is vertically movably attached to an air cylinder 24 in the holding body 23 via a shaft 24a. Further, in the holding body 23, a rotary motor 25 is attached independently of the cylindrical body 29. Further, a bolt engagement portion 27 having a steel ball 28 is attached to the rotary motor 25 via a trick guard 26. The steel ball 28 comes into contact with a cylindrical body 29 that descends by the air cylinder 24, is drawn inward in the radial direction, and is fitted into the neck portion of the bolt 7 to clamp the bolt 7. Further, the torque guard 26 protects the rotary motor 25 from overload.

Further, on the outer surface of the holding body 23, a protrusion 23a extending in the longitudinal direction is formed.
On the other hand, the device body 10 is provided with a groove portion 16 that engages with the protrusion 23a. A guide device is constituted by the groove portion 16 and the protrusion 23a, and the fastener holding mechanism 22 is guided right above the channel fastener 6 by this guide device. Further, taper is formed at both upper and lower end portions of the groove portion 16 and the protruding portion 23a so that they can be smoothly engaged with each other.

In addition, each air cylinder 14, 24 and motor 13,
The driving of 25 is performed by the air supplied from the refueling machine 38 and a dedicated power source. In addition, an electromagnetic valve (not shown) is installed inside the apparatus body 10, and the electromagnetic valve is switched by a control signal from the control box of the fuel exchanger 38 to drive the air cylinder 14 and the air cylinder 24. Also, it is possible to make three selections of disconnection of supply of the air cylinder 24.

The supply of the air cylinder 24 is cut off because the stroke of the bolt 7 which moves vertically in accordance with the loosening or tightening rotation of the bolt 7 is absorbed by the air cylinder 24. Further, the respective motors 13 and 25 are switched and driven to rotate by a control box provided on the fuel exchanger 38.

Next, the operation of this embodiment having such a configuration will be described.

First, as shown in FIG. 3, the fuel assembly 2 with the channel box is moved from the inside of the reactor 40 into the fuel storage rack 5 through the reactor well 39.

Next, the hoist 9 of the refueling machine 38 is used to mount the channel fastener device of the present invention directly above the fuel assembly 2 with the channel box. The mounting operation of the channel fastener device is performed by engaging the guide 10a of the device body 10 with the fuel handle 3.

Next, the motor 13 is driven to swivel the swivel shaft 11 to bring the air cylinder 14 directly above the channel fastener 6 of the fuel assembly 2. In this case, the air cylinder 14
The fastener holding mechanism 22 is lifted upward by the air cylinder 24, and the cylinder 29 is lifted upward by the air cylinder 24.

Next, the air cylinder 14 is driven to drive the fastener holding mechanism 22.
While the projection 23a is engaged with the groove 16 of the apparatus main body 10 and lowered, the bolt engaging portion 27 of the fastener holding mechanism 22 is seated and engaged with the bolt 7 of the channel fastener 6. This seated state is detected by the control box of the fuel exchanger 38.

Next, the air cylinder 24 is driven to lower the cylindrical body 29, and the neck portion of the bolt 7 is clamped by the steel ball 28. Subsequently, the air cylinder 24 is set to a state where the air supply is cut off, the motor 15 is driven to rotate the bolt engaging portion 27, and the bolt 7 is removed from the stud 8 of the fuel assembly 2. Then the air cylinder 14
Is driven to raise the fastener holding mechanism 22 to lift the channel fastener 6 and the bolt 7 as a unit. Subsequently, the motor 13 is driven to rotate the air cylinder 14,
Bring the channel fastener 6 to just above the channel fastener receiver 30 provided below the device body 10. Then, the air cylinder 24 is driven to lift the cylindrical body 29, and the state in which the neck portion of the bolt 7 is clamped by the steel ball 28 is released,
The channel fastener 6 and the bolt 7 are dropped and stored in the channel fastener receiver 30.

Thus, the channel fastener 6 is removed from the fuel assembly 2 by the channel fastener desorption device, and the channel fastener desorption device is attached to the next fuel assembly 2.

Next, another embodiment of the channel fastener attaching / detaching device of the present invention will be described with reference to FIGS. 4 and 5.

As shown in FIG. 4, an air cylinder 14 is fixed to one side of the device body 10 and the device body is attached to the other side of the device body 10.
A balance adjuster 31 for keeping the balance of 10 is fixed.

On the other hand, the fuel storage rack 5 is equipped with a channel fastener storage container 32 independently of the channel fastener attaching / detaching device. The channel fastener storage container 32 is composed of a container body 34 having a fixing jig 36 attached to the upper end. The fixing jig 36 is engaged with the upper end of the fuel storage rack 5. Also, hold the container handle at one side of the upper end of the container body 34.
33 is attached, and on the other hand, a counterweight 37 is attached to the other side of the upper end of the container body 34 in order to maintain the balance when the channel fastener storage container 32 is hung.
The container handle 33 has the same shape as the fuel handle 3 so that it can be gripped by the fuel exchanger 38. Further container body 34
A guide 35 is provided at the lower end portion of the device for smoothly mounting the channel fastener storage container 32 in the fuel storage rack 5. The container body 34 is slightly smaller than the fuel storage rack 5, and the fuel storage rack 5 can be smoothly
It can be installed inside.

 Next, the operation of this embodiment will be described.

The channel fastener storage container 32 is mounted in the fuel storage rack 5 by holding the container handle 33 by the fuel exchanger 38 and lifting it. Next, the fuel exchanger 38 lifts and moves the channel fastener attaching / detaching device, and brings the channel fastener attaching / detaching device to directly above the predetermined fuel assembly 2 with the channel box. With this channel fastener attaching / detaching device, the channel fastener 6 is removed in the same manner as described above. Then, the removed channel fastener 6 is carried directly above the channel fastener storage container 32 by moving the refueling machine 38, and then drops into the channel fastener storage container 32 and is stored therein.

In each of the above embodiments, the channel fastener attaching / detaching device is mounted on the fuel assembly 2 with a channel box arranged in the fuel storage rack 5 and the channel fastener 6 is removed. Machine 42
The fuel assembly 2 with the channel box may be arranged on the top, and the channel fastener attaching / detaching device may be mounted on the fuel assembly 2 with the channel box.

〔The invention's effect〕

According to the present invention, the drive motor rotates the drive cylinder about the rotation axis, the drive cylinder lowers the shaft, and the protrusion provided on the holding body of the fastener holding mechanism engages with the groove of the apparatus main body. As a result, the fastener holding mechanism can be guided right above the desired bolt, and the bolt engaging portion can be easily engaged with the desired bolt. When the rotary motor is driven to loosen or tighten the bolt by the bolt engaging portion, the stroke of the vertically moving bolt can be absorbed by the absorbing cylinder. In this way, the channel fastener can be easily and easily removed from the fuel assembly with the channel box. Further, the removed channel box can be easily and easily put into the container body from above, and the removed channel box can be easily stored.

[Brief description of drawings]

FIG. 1 is a side view showing an embodiment of a channel fastener attaching / detaching device according to the present invention, FIG. 2 is an enlarged detailed view showing a fastener pinching mechanism, FIG. 3 is a view showing an operation of the present invention, and FIG. FIG. 5 is a side view showing another embodiment according to the invention, FIG. 5 is a side view showing a channel fastener storage container, FIG. 6 and FIG.
FIG. 8 is a view showing a conventional channel box removing work, and FIG. 8 is a perspective view showing a fuel assembly and a channel box. 2 ... Fuel assembly, 3 ... Fuel handle, 4 ... Channel box, 5 ... Fuel storage rack, 6 ... Channel fastener, 7 ... Bolt, 10 ... Device body, 14 ... Air cylinder, 22 ...... Fastener clamping mechanism, 24 …… Air cylinder, 27 …… Bolt engaging part, 28 …… Steel ball, 29 …… Cylinder body,
30 …… Channel fastener receiver, 32 …… Channel fastener storage container, 34 …… Container body, 35 …… Guide, 36 …… Fixing jig.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References 60-156497 (JP, U) actual 60-148994 (JP, U) actual 60-127597 (JP, U) actual

Claims (3)

(57) [Claims] 1. A device main body having a lower end attached to a fuel handle of a fuel assembly, a vertical drive mechanism provided on a side of the device main body, and a channel provided at a lower end of the vertical drive mechanism. A fastener holding mechanism having a rotatable bolt engaging portion that engages with a bolt of the fastener, and the vertical drive mechanism is provided in the main body of the apparatus via a turning shaft and is turned by a turning motor fixed to the turning shaft. A fastener having a drive cylinder and a shaft extending downward from the drive cylinder; and the fastener holding mechanism having a protrusion outwardly slid along a groove of the apparatus body and connected to the shaft. A rotation motor that rotates the engagement portion and a rotation motor that is provided in the holding body so as to be connected to the rotation motor, and moves in the vertical direction as the bolt loosens or is tightened and rotated. A channel fastener attaching / detaching device, comprising: an absorption cylinder that absorbs a stroke of a bolt. 2. The channel fastener attaching / detaching device according to claim 1, wherein the device main body has a balance adjuster on a side opposite to a side where the vertical drive mechanism is provided. 3. A container body for accommodating a channel fastener, a fixing jig provided at an upper end portion of the container body and engaged with an upper end of a fuel storage rack, and a conical shape formed at a lower end portion of the container body. A channel fastener storage container, characterized in that it has a guide.