JPS5828556B2 - Furnace equipment drawer removal device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for pulling out and carrying out in-core equipment, for example, for pulling out and carrying out a used in-core neutron detector or the like from inside a reactor.

In a nuclear reactor such as a BWR reactor, when recovering an in-core neutron detector, it is rolled up and recovered in a pedestal below the reactor vessel, and the rolled up and recovered detector is placed in a cask. The radioactivity is prevented from dispersing by storing it in a container, transporting it to a pool, and storing it there for a predetermined period of time.

However, conventionally, this type of collection work has relied on manual labor for transportation, and the detectors mentioned above are highly radioactive.
The above recovery work had disadvantages such as a high risk of radiation exposure.

In view of these points, the present invention provides an in-core neutron detector, etc., in which the extraction and cutting of the detector, the storage in the cask, and the transfer of the cask can be carried out consistently and easily within the pedestal. The purpose of the present invention is to provide a device for extracting and carrying out equipment in a furnace.

Hereinafter, one embodiment of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 denotes a running underframe which has a medium shape, has running wheels 11 at its lower part, and can run on the pedestal floor surface. A main plate 12 made of a plate is erected.

On one side of the main plate 12, there is a pair of IJs 14 and 15 that sandwich and guide an in-reactor neutron detector 13 in the form of a cable with a circular cross section, which is pulled out from the reactor vessel (not shown).
A removal tool 17 that can grasp and lower the in-reactor neutron detector 13 is disposed below the boos 1.1-14, 15, and further below the removal tool 17. A cutter 18 is provided to cut the detector 13 into a predetermined length.

By the way, the lower pulley 14 of the pair of boots IJ 14 and 15 is rotatably mounted on a shaft 19 that projects forward from the main plate 12.
On the other hand, the other pulley 15 is rotatably attached to a shaft 21 attached to the tip of an arm 20 that is pivotably attached to the shaft 19, and rotates at a predetermined angle along the upper outer periphery of the pulley 14. It is possible to swing around the center.

That is, as shown in FIG. 2, the main plate 12 has a pulley mounting seat 22, a washer 23, and a locking nut 2.
4, a shaft 19 is implanted so as to protrude from one side of the shaft 19, and a pulley 14 having a circumferential groove 14a on the outer periphery is attached to the shaft 19 via a metal 25. The base end of the arm 20 is loosely fitted into the free end.

In addition, the symbol 26at26b in the figure is a disc-shaped sliding collar,
27 is a locking nut.

A shaft 21 for mounting the other pulley 15 is inserted through the free end of the arm 20, and the pulley 15 is rotatably mounted on the shaft 21 via a metal 28. .

The thickness of the pulley 15 is determined by the circumferential groove 1 of the pulley 14.
The width of the pulley 15 is the same as the width of the pulley 14, and the outer circumferential portion of the pulley 15 is partially fitted into the circumferential groove 14a, so that the outer circumferential surface of the pulley 15 and the circumferential groove 14 of the pulley 14 are
The in-core neutron detector 13 can be held between the bottom surface of

Further, a guide member 29 having an arc-shaped guide groove 29a is fixed to the main plate 12 via a mounting seat 30, and a cylinder into which one end of the shaft 21 can be inserted is provided at both ends of the guide groove 29a. A locking member 31 having a shape of 31 is inserted through the main plate 12 so as to protrude on the side opposite to the guide member 29, and the shaft 21 is guided and engaged with the guide groove 29a.

On the other hand, a collar 32 is fixed to the shaft 21 on the side opposite to the pulley 15 with respect to the arm 19, and a collar 32 is fixed to the arm 19 and is connected to a spring cap 33 disposed so as to surround the shaft 21. A coil spring 34 is interposed between them, and a bundle 35 is disposed at the other end of the shaft 21.
is the installation.

When the bundle 35 is held and the shaft 21 is pulled out from the locking tool 31, the shaft 21 is moved along the guide groove 29a to the two boobies IJ 14 ,
15 can move on an arcuate line while maintaining the engaged state, and when the hand is released at the end of the guide groove 29a, the tip of the shaft 21 is moved into the corresponding locking tool 31 by the action of the coil spring 24. is inserted and fixed.

A pneumatic cylinder device 36 is provided on one side of the traveling frame 10.
is arranged upright, and its piston rod 37 is configured to move up and down by supplying and discharging compressed air, and the removal tool 17 is attached to the piston rod 37 via an inverted-shaped connecting member 38. There is.

That is, the casing 39 of the removal tool 17
As shown in FIGS. 1 and 3, the pneumatic cylinder device 36 is slidably disposed along the pneumatic cylinder device 36, and is connected to the pneumatic cylinder device 36 via a connecting member 38 depending on the up and down of the piston rod 37. can be moved up and down along the

Furthermore, a pneumatic cylinder device 40 having a piston rod 40a that can move forward and backward in a direction orthogonal to the axis of the air cylinder device 36 is installed in the casing 39, and supplies pressurized air through an air supply hole 41. When the air is supplied, the piston rod 40a retreats and the air supply hole 4
1 is connected to the exhaust side, the piston rod 40a is caused to protrude by a spring 42.

Further, at the distal end of the casing 39, a guide portion 44a that guides one side of the movable press contact piece 43 provided at the distal end of the piston rod 40a and the movable press contact piece 43 are provided.
An L-shaped member 44 (FIG. 4) having a fixed pressure contact piece 44b protruding so as to face the front surface of the removable tool 17 is provided at the tip of the L-shaped member 44 (FIG. 4). A switch roller 47 is mounted which comes into contact with a microswitch 45 that detects its upper limit position and a microswitch 46 that detects its lower limit position in accordance with the above.

Further, a cutter 18 for cutting the detector 13 is provided at the lower part of the removal tool 17 as described above.

That is, the cylinder 48 of the cutter 18 is fixed on the top plate 10a of the traveling frame 10, and the cylinder 48 is moved in the operating direction by the supply of compressed air, and is moved back by the spring 49 when the cylinder 48 is discharged. A ram 50 is built in, and a cutting blade 51 is provided at the tip of the ram 50, protruding from the tip surface of the cylinder 48 (FIG. 5).

On the other hand, at a position facing the cutting blade 51, a stand 52 is erected from the top plate 10a of the traveling underframe 10, and a blade receiver 53 that cooperates with the cutting blade 51 is attached to the front surface of the stand 52. has been done.

Further, the top plate 10a of the traveling frame 10 is provided with an opening 54 for dropping the detector, which is cut at a position directly below the tip of the cutting blade 51, and the detector 13 is guided through the opening 54. A cutter holder 55 is attached to support the cutter 18.

By the way, a cask 57 mounted on a cask transfer trolley 56 can be moved in and out of the inside of the traveling frame 10.

The main body of the cask 57 has a cubic shape, and a sheathing material such as lead is layered on the inner surface of an outer wall made of stainless steel, and a central opening 58a is formed at the upper opening by the sheathing material as well. A first lid 58 is attached thereto, and a second lid 59 is further attached to the central opening 58a.

Both sides of the second lid 59 are formed with tapered parts that gradually become narrower toward the bottom, and the central opening 58 of the first lid 58
The inner lids 58 and 59 are provided with handles 60 and 60 respectively on the upper surfaces of the inner lids 58 and 59.
61 is attached and can be removed by hand.

A clamp device 62 is also provided at the top end of the main body of the cask 57.
is provided, and when the lid is closed, the lid is fixed by the clamp device 62 using a wing nut 63 or the like.

Further, the main body of the cask 57 is provided with hanging ears 64, and the cask 57 can be lifted from the cask transfer cart 56 using a wire rope 65 or the like as appropriate.

In FIG. 1, reference numeral 66 is a drain port for draining water when the cask 57 is lifted out of the water of the pool, and 67 is a stopper thereof.

Next, its effect will be explained.

First, when pulling out the in-core neutron detector 13 from the reactor vessel, pull the handle 35 toward you and move the boot 915 to the first
Swing it to the left from the position shown in the figure and fix it in that position.
In-core neutron detector 13 protruding below the reactor vessel
is covered with a transparent synthetic resin tube such as vinyl or polyethylene, and the in-furnace neutron detector 13 is inserted between both pulleys 14 and 15, and further pulled down along the fixed side pressure contact piece 44b of the removal tool 17, It is made to look over an opening 54 provided in the top plate 10a of the traveling frame 10 along the cutter receiving blade 53.

Therefore, the pulley 15 is moved to the position shown in FIG. 1 using the handle 35, the in-reactor neutron detector 13 is sandwiched between the two boos IJ14 and 15, and the cask 57 from which the second lid 59 has been removed is transferred to the cask. The lid 5 of the suspension 1 of the cask 57 is inserted into the traveling underframe 10 together with the trolley 56.
8 is positioned directly below the opening 54 provided in the top plate 10a of the traveling underframe 10.

Therefore, when the pneumatic cylinder device 36 is driven and its piston rod 37 is moved upward, the removal tool 17 is also moved upward accordingly.

In this way, the removal tool 11 moves upward by a predetermined amount,
When the switch roller 47 comes into contact with the microswitch 45 that detects the upper limit position of the removal tool 17, the operation of the pneumatic cylinder device 36 is stopped, and the air supply hole 41 of the pneumatic cylinder device 40 of the removal tool 17 is moved to the exhaust side. will be communicated to.

Therefore, the piston rod 40a is moved forward by the spring 43, and the in-furnace neutron detector 13 is clamped between the movable side pressure contact piece 43 and the fixed side pressure contact piece 44b provided at the tip thereof.

When the in-core neutron detector 13 is clamped by the removal tool 17 in this way, the pneumatic cylinder device 36
is activated, and the removal tool 17 is lowered via the piston rod 47 and the connecting member 38.

Therefore, as it descends, the in-core neutron detector 13
is pulled out of the reactor vessel while being guided by both pulleys 14,15.

As the removal tool/I/11 descends, the S.1' roller 47 provided at its tip comes into contact with the micro switch 46 that detects the lower limit position, and the operation of the pneumatic cylinder device 36 is stopped, and at the same time the cutter 18 Pressurized air is supplied into the cylinder 48 of.

The ram 50 moves forward, and the in-core neutron detector 13 is cut by the action of the cutting blade 51 and the blade receiver 53 provided at its tip, and the in-core neutron detector 1 is cut off.
3 is dropped and stored in the cask 57 through the opening 54.

When the in-core neutron detector 13 is cut by the cutting blade 51, the pneumatic cylinder device 4 of the removal tool 17
0 is supplied with pressurized air.

Therefore, the piston rod 40a is moved backward against the elastic force of the spring 42, the movable side pressure contact piece 43 separates from the fixed side pressure contact piece 44b, and the clamping state of the in-core neutron detector 13 is released.

Then, the pneumatic cylinder device 36 is operated again to move the remover tool 17 upward, and the in-core neutron detector 13 is gripped at its upper limit position, and the same operation as described above is repeated thereafter.

Therefore, the in-core neutron detector 13 is pulled out and cut into predetermined lengths, and sequentially stored in the cask 57.

When the predetermined amount of in-core neutron detectors 13 have been pulled out and recovered, the pulley 15 is returned to the left position in FIG.
5 etc., and move the traveling trolley 10 from the fixed position.
After moving, the second lid 59 is attached to the cask 57 and sealed, the lid 59 etc. are fixed with a clamp 62, and the cask 57 is manually pushed together with the cask transfer trolley 56 to the stairwell leading to the upper floor. etc. to move it,
Therefore, hook the hanging ear 64 and use the wire rope 65 as appropriate.
The cask 51 is lifted up to the pool installation location on the floor, where the lids 58 and 59 of the cask 57 are removed and immersed in the pool water, and the cut in-core neutron detector 13 housed in the cask 57 is removed. The inner box made of wire mesh or the like is taken out from the cask and stored in the pool water.

As explained above, in the present invention, a pulley, a removal tool, and a cutter are provided in the traveling frame to sandwich and guide the detector, and the cask can be moved in and out of the traveling frame, and the operation of the removal tool and cutter is controlled by pneumatic pressure. Since this is carried out using a cylinder device, the removal and recovery of in-core neutron detectors, etc. can be mostly automated, and these operations can therefore be performed by remote control, which can greatly reduce the number of personnel required for this work. The risk of radiation exposure to workers can be prevented.

Moreover, the pulley is rotatably mounted on the horizontal axis,
Another pulley is pivotably attached to the tip of an arm swingably attached to the horizontal shaft, is swingable at a predetermined angle along the upper outer periphery of the pulley, and is fixed in position at both ends of the swing. Since the in-reactor neutron detector, etc. is sandwiched and guided by a pair of guide pulleys, when inserting the neutron detector, etc. between the guide pulleys, the upper pulley must be moved to the left position in Fig. 1. By moving it, a neutron detector or the like can be inserted between the two pulleys in a substantially straight line, and the insertion can be easily performed.

On the other hand, when pulling out an in-reactor neutron detector etc. from the inside of the reactor, the above-mentioned detector etc. can be bent and held in an S-shape by swinging the upper pulley to the position shown in FIG. Even when the grip by the removal tool is released, the in-reactor neutron detector, etc. is reliably held between the guide pulleys, and the in-reactor neutron detector, etc. can be reliably held in a predetermined position after the removal tool is moved upward. This allows the detector, etc. to be pulled out reliably.

Further, the device itself can be made compact, and it is possible to work in a narrow space with great ease.

[Brief explanation of drawings]

Fig. 1 is a partially sectional front view schematically showing the device of the present invention;
The figures are a longitudinal side view of the guide pulley, Fig. 3 is a longitudinal side view of the removal tool, Fig. 4 is a plan sectional view taken along the line N-■ in Fig. 1, and Fig. 5 is a longitudinal side view of the cutter. Figure 6 is a plan view of the cask. 10... Travel underframe, 10a... Top plate,
12... Main plate, 13... In-reactor neutron detector, 14°15...7'-IJ,
17... Removal tool, 18...
Cutter, 36, 40... pneumatic cylinder device,
43...Movable side pressure contact piece, 51...Cutting blade, 56...Cask transfer trolley, 51...
...Cask.

Claims (1)

[Claims] 1 A pulley is attached to a traveling frame that is movably disposed on the pedestal floor so that it can rotate about a horizontal axis, and a shaft is attached to the tip of an arm that is attached so that it can swing about the horizontal axis. and another pulley that can swing at a predetermined angle along the upper outer periphery of the pulley and can be fixed in position at both swinging ends, and a pair of guides for pinching and guiding the furnace equipment by both pulleys. A pulley and a guide pulley disposed below the in-furnace equipment grip the in-furnace equipment and lower the in-furnace equipment by a predetermined distance using a pneumatic cylinder device to pull out the in-furnace equipment a predetermined length. A cutter disposed below the tool for cutting the furnace equipment pulled out by the removal tool is installed, and the furnace equipment pulled out by the removal tool LK and cut by the cutter is stored. A cask that can be sealed with a lid can be moved in and out of the traveling platform frame,
Furnace equipment drawer removal device.