JPS63127805A - Cutting device for long workpiece - Google Patents

Abstract

PURPOSE:To improve cutting capacity by fixing a long workpiece with a clamping cylinder mechanism to crush a cut portion with a pushing cutter and a cutter receiver while the fixed portion is moved toward a piston to bent and cut off the workpiece by a bending cylinder mechanism about the fulcrum of cut portion. CONSTITUTION:A measuring pipe P for neutron to be scrapped is applied to respective receiving portions 44, 45 of upper and lower portions gripping cylinder mechanisms 2, 3 and a blade receiving portion 69 of a cutting cylinder mechanism 4. Then, pressurized water is supplied to press cylinder mechanisms 12, 13 to push out press portions 28, 29 to clamp the pipe P between the receiving portions 44, 45. Further, pressurized water is supplied to the cylinder mechanism 4 to push out a pushing blade 68 and crush the pipe P between the pushing edge 68 and the edge receiving portion 69, and further supplied to bending cylinders 5, 6 and the cylinder mechanisms 12, 13 as the pipe P is crushed. Thus, the pipe P is bent about the fulcrum of blade receiving portion 69 to be easily cut off so that the sharpness of cutting edge is not needed and the cutting capacity is improved to shorten a time taken for exchanging the cutting edge.

Description

Detailed Description of the Invention (Objective of the Invention) (Industrial Application Field) The present invention relates to a cutting device for long objects such as disposal neutron measuring tubes in boiling water nuclear reactors, and in particular, The present invention relates to a long object cutting device having a bending cylinder mechanism capable of bending the long object using the cutting point as a fulcrum.

(Prior technology) Generally, the neutron measurement tubes installed in the core of a boiling water reactor are replaced with new tubes several times at each periodic inspection, and the neutron measurement tubes for disposal after use are placed in the spent fuel storage pool. will be stored for a certain period of time. There is no dedicated storage space for the disposal neutron measurement tubes in this spent fuel storage pool, so the disposal neutron measurement tubes are hung in bundles of several dozen on the wall of the spent fuel storage pool. Fuel is stored horizontally in the narrow gap between the wall of the spent fuel storage pool and the spent fuel storage rack.

Disposable neutron measuring tubes whose radioactivity has decreased after being stored for a certain period of time are grasped by a grasping device suspended from an auxiliary hoist or the like on the refueling platform, and removed from the bundle of discarded neutron measuring tubes. The removed neutron measurement tube for disposal is moved to an underwater cutting machine suspended from an overhead crane or auxiliary hoist via a wire rope.

Since the neutron measuring tube for disposal has a length of about 13 m, its upper part is grasped and suspended by a grasping device, and the cut point is applied to an underwater cutter. Since the underwater cutter has a cutting tool at the upper part and a gripping tool at the lower part, the upper part of the cutting part of the disposal neutron measurement tube is fixed by the gripping device, and the lower part is fixed by the gripping tool of the underwater cutting machine. Then, the cutting portion of the disposal neutron measurement tube is pressed between the push blade and the blade receiver of the cutting tool of the underwater cutting machine.

Since the neutron measurement tube for disposal has a pipe structure, the pipe structure is cut in a collapsed state and the cut opening is sealed. Therefore, the contents of the disposal neutron measurement tube do not leak to the outside, so the pool water will not be contaminated. Since the neutron measuring tube for disposal is usually divided into three equal parts, after the above-mentioned cutting, the lower piece is allowed to fall naturally by opening the grip, and after the upper piece is further cut, it is allowed to fall naturally as well.

The cut neutron measuring tube for disposal fell naturally into a container called a can, which was a war item on the spent fuel storage rack at the bottom, and the cut neutron measuring tube for disposal stored in the can was placed in the container. i? It is packed into tanks, transported to rad tanks, and stored.

(Problems to be Solved by the Invention) In one periodic inspection, about 10 neutron measuring tubes for disposal are cut. Normally, one neutron measurement tube for disposal is divided into three equal parts, so the number of cuts is about 20. Conventionally, the push blades of underwater cutting machines used for cutting had sharp edges and good cutting ability.

However, because discarded neutron measurement tubes are generally highly radioactive and have a hardened surface, the cutting edge of the push blade often breaks or peels off from the tip if the tube is cut many times. If the pushing blade loses its sharpness and the neutron measurement tube for disposal cannot be cut by pressing alone, the cutting operation will stall and the pushing blade will need to be replaced. however,
Since it takes a considerable amount of time to replace the pusher blades, it is desirable from the economic point of view of the pusher blades to have as few replacements as possible.

In order to prevent the cutting edge of the pressing blade from chipping or peeling off, the cutting edge of the pressing blade may be made obtuse, but this causes the problem that the cutting edge of the pressing blade deteriorates and the cutting operation cannot proceed smoothly.

The present invention was made in consideration of the above circumstances, and it is possible to improve the cutting ability without requiring a push blade with a sharp cutting edge, thus reducing the number of replacements of the push blade,
It is an object of the present invention to provide a long object cutting device capable of shortening working time and improving cutting performance.

[Structure of the invention]

(Means for Solving the Problems) A long object cutting device according to the present invention includes a gripping cylinder freezing structure for fixing a long object to a main body frame that can be suspended from a wire rope, etc. A g'J cutting cylinder mechanism is provided for pressing and cutting an object, and the gripping cylinder mechanism moves a fixed part of the long object in the direction of the piston axis and bends the long object using the pressing cutting part as a fulcrum. It has a bending cylinder mechanism that can be bent.

(Operation) A long object cutting device is suspended from a wire rope or the like, and the long object suspended by a gripping device or the like is applied to the long object cutting device. After this elongated object is fixed by the gripping cylinder mechanism, the push blade of the cutting cylinder mechanism is pressed against the elongated object.

For long objects, the cut portion is crushed between the push blade and the blade receiver. At this time, when the bending cylinder mechanism included in the grasping cylinder mechanism is activated to move the fixed portion of the elongated object in the direction of the piston axis, the elongated object is bent using the cut portion as a fulcrum.

A long object can be easily cut by both the pressing force and the bending force. Therefore, a sharp pushing blade is not required, and the cutting edge of the pushing blade is less likely to chip or peel off, which extends the life of the pushing blade and reduces the number of replacements of the pushing blade.

(Example) A long object cutting device according to the present invention will be described with reference to the drawings.

As shown in Fig. 1, the long object cutting device has an upper gripping cylinder mechanism 2 and a lower gripping cylinder mechanism 3 arranged side by side on a main body frame 1 that can be suspended from a wire rope. A cutting cylinder mechanism 4 is provided. Both gripping cylinder mechanisms 2゜3 each have a bending cylinder of 1gl.
It has 5 and 6.

As shown in FIG. 2, the main frame 1 includes side plates 9 and 10 fixed to both sides of an upper frame 8 with mounting bolts 11. A lifting rod 8a to which a wire rope connection fitting can be connected is provided at the center of the upper frame 8.

The lower gripping cylinder mechanism 2 is the lower gripping cylinder mechanism 3.
Since the lower gripping cylinder mechanism 3 has the same structure as the lower gripping cylinder mechanism 3, the explanation will be given by taking the lower gripping cylinder mechanism 3 as an example. The lower gripping cylinder machine @3 is composed of a pressing cylinder mechanism 13 fixed to the right side plate 10 in FIG. 1, and a bending cylinder mechanism 6 opposite to this pressing cylinder mechanism 13 and fixed to the left side plate 9. be done.

In the suppression cylinder mechanism 13, a piston 17 is slidably housed in a cylinder 15.
Cylinder '119a isolated in chamber.

19b is provided. Each cylinder chamber 19a, 19b has a watertight structure.

A penstock pipe 218.21b is provided for supplying and discharging pressurized water to and from the pipe 19b.

A piston rod 23 extends from the piston 17, and a bearing metal 27 is attached to the cylinder 15 and cylinder cover 25.
A pressing portion 29 is provided at the tip of the piston rod 23 .

On the other hand, in the bending cylinder mechanism 6, a cylinder 31 and a housing 33 are screwed together to form a cylinder chamber 35, and the housing 33 is fixed to the side plate 9.

A piston 37 is slidably housed in the cylinder v35, and a penstock pipe 39 for supplying and discharging pressure water is provided in the cylinder chamber 35.

A piston rod 41 extends from the piston 37, and the piston rod 41 is supported by the cylinder 31 and the side plate 9 via a metal 43.

A receiving portion 45 is provided at the tip of the piston rod 41. The receiving portion 45 and the pressing portion 29 each have a recess that fits the shape of a long object such as a neutron measuring tube P for disposal, and the long object is gripped between the receiving portion 45 and the pressing portion 29. It is supposed to be done.

The cutting cylinder mechanism 4 is bolted to the main body frame 1 as shown in FIGS. 1 and 3.

This cutting cylinder mechanism 4 has a substantially cylindrical or prismatic block shape, and the cutting portion is formed in a U-shape so that a long object such as a neutron measurement tube P can be applied thereto.

The cutting cylinder mechanism 4 is composed of a front cylinder 50 and a rear cylinder 51. In the rear cylinder 51, the inside of the cylinder block 52 is isolated by a piston 53 into two cylinder chambers 54a, 54b, and both cylinder chambers 54a,
Hydraulic pipes 55a and 55b are provided to supply pressurized water to 54b. A piston rod 56 extending rearward from the piston 53 is supported by a cylinder cover 57 fixed to the cylinder block 52 via a metal support 58, and its tip end is protected by a guard 59.

The rear cylinder 51 is flange-fixed to the side plate 10 via a blanket 60, as shown in FIG.

In the other front cylinder 50, the cylinder block 52 of the rear cylinder 51 is fixed to a cylinder block 62 to form one cylinder chamber 63.

Pressure water is also supplied to this cylinder chamber 63 from the water penstock 55a. A piston 64 is slidably accommodated in the cylinder chamber 63, and the piston 64 is fixed to a piston rod 65 extending from the piston 53 of the rear cylinder 51.

Piston rod 66 further forward from the piston 64
extends, and a push blade 68 is replaceably attached to its tip. A blade holder 69 is provided opposite the push blade 68, and the tip of this blade holder 69 is formed in a chevron shape. A long object is pressed and cut between this blade receiver 69 and the pushing blade 68.

FIG. 4 shows each hydraulic pipe 20a of the long object cutting device.

20b, 21a, 21b, 38.39.55a.

A water pressure pump 70 that supplies and drains pressure water to 55b and a water supply and drainage system are shown.

In the water pressure pump 70, an air piping 72 from a service air 71 is branched into two systems and connected to water tanks 73 and 74, respectively.

Since each system has the same configuration, only one will be explained. The branched wiring @72a is connected to a pump 79, with a filter 75, a regulator 76, an oiler 77, and a valve 78 interposed in this order.

A discharge pipe 80 extends from the pump 79, and a water supply joint 81 is provided at the tip thereof. The discharge pipe 80 is provided with a discharge branch pipe 82 , which opens into the water tank 73 via a valve 83 . In addition, the discharge pipe 8
0 is provided with a water pressure gauge 84. The water tank 73 is further provided with a drainage joint 85 for a return grove.

On the other hand, on the long object cutting device side, there are press cylinder joints 90a, 90b that can be easily attached to and detached from the above-mentioned respective joints 81 and 85.
Cutting cylinder joints 91a, 91b.

A bending cylinder joint 92 is provided. The pressure cylinder joint 90a is connected to the hydraulic pipes 20a, 21a of both pressure cylinders 12.13 via flexible water supply and drainage hoses. Further, the press cylinder joint 90b is similarly connected to the penstock pipes 20b and 21b. Furthermore, a cutting cylinder joint 91a.

911) are connected to each penstock 55a, 55b, and a bending cylinder coupling 92 is also connected to each penstock 38, 39.

Next, an explanation will be given of the operation when the long object cutting device configured as described above is applied to an underwater cutting machine for disposal neutron measurement tubes used during periodic inspections of boiling water nuclear reactors.

In a boiling water reactor, a neutron measuring tube P for disposal is stored in the pool water of the spent fuel storage pool at the top of the reactor.
A refueling platform and overhead crane are installed above the spent fuel storage pool.

First, a wire rope from an overhead crane or an auxiliary hoist is connected to the lifting rod 8a of the long object cutting device via a connecting fitting, and the long object cutting device is suspended from above the fuel exchange platform into the pool water.

A water pressure pump 70 is installed on the fuel exchange platform, and a pressure cylinder fitting 90b from a long object cutting device is connected to a water supply joint 81 of this water pressure pump 70.
When pressure water is supplied, the pressure water passes through the penstock pipes 20b and 21b and enters the cylinder chamber 18 of the double press cylinder mechanism 12.13.
b, 19b are simultaneously supplied with water and the piston rod 22.2
3 retreats, and the space between the pressing part 28.29 and the receiving part 44.45 opens. After the pressing parts 28 and 29 open, the water supply joint 81
Remove the pressure cylinder joint 90b.

Since the pressure water does not escape when the suppression cylinder joint 90b is removed, the pressing portions 28 and 29 remain retracted.

Similarly, when the cutting cylinder joint 91b is connected to the water supply joint 81 and pressurized water is supplied, the pressure water is supplied to the cylinder chamber 54b of the cutting cylinder mechanism 4, and the push blade 68 retreats. Furthermore, when the bending cylinder joint 91b is connected to the water supply joint 81 and pressure water is supplied, the pressure water is supplied to the cylinder chamber 34.35 of each bending cylinder mechanism 5.6, and the receiving portions 44 and 45 move forward. It will be in the most protruding state. At this most protruding state, the upper gripping cylinder mechanism 2
The receiving portion 44 of the cutting cylinder mechanism 4, the six blade holders of the cutting cylinder mechanism 4, and the receiving portion 45 of the lower gripping cylinder mechanism 2 are aligned in a straight line, and the neutron measuring tube P for disposal can be applied.

Then, using a gripping device suspended from a wire rope etc. from an auxiliary hoist, the disposal neutron measurement tube P in the pool water is removed.
, and move it in the pool water, and apply the disposal neutron measuring tube P to the suspended long object cutting device.

After applying the disposal neutron measuring tube P, connect the suppression cylinder joint 90a to the water supply joint 81 to supply pressure water, and connect the pressure cylinder joint 90b to the drain joint 85, each suppression cylinder line groove 12 .13 is the pressing part 28.2
9 and firmly grasp the disposal neutron measuring tube P between it and the receiving parts 44 and 45. The gripped state is shown in FIG. Even after gripping, each joint 90a, 90b remains connected.

Then, when the cutting cylinder joint 91a is connected to the water supply joint 81 to supply pressure water, and the cutting cylinder joint 91b is connected to the drain joint 85, both the front cylinder 50 and the rear cylinder 51 of the cutting cylinder mechanism 4 are connected. Cylinder empty 54a
, 63 are supplied with pressure water, and the cutting cylinder mechanism 4 powerfully pushes out the push blade 68. Pushed out push blade 68
presses the disposal neutron measuring tube P between the blade receiver 69 and crushes the pipe structure. And this push blade 68
While pressing with
Pressure water is further supplied to the cylinder chambers 18a and 19a of No.3.

By this operation, both receiving portions 44 and 45 are inserted into the cylinder chamber 34.
．． 35, and is pushed backward by the opposing pressing parts 28 and 29. For this reason, the neutron measurement tube P for disposal can be bent using the six blade holders as fulcrums, and the neutron measuring tube P for disposal can be
4.45 and the pressing part 28.29 are the neutron measurement tube P for disposal.
Since the object is moved while being held tightly, a tensile force is also generated. The neutron measurement tube P for disposal is pressed by the push blade 68,
Since cracks are formed on both sides of the abutting part, bending and tensile forces are applied to the cracks, and the parts are easily cut.

After cutting, pull back the pushing blade 68 and the pushing part 28.29 to open the disposal neutron measuring tube P, and then push the receiving part 45 again.
Prepare for cutting by pushing out the blade, and continue cutting using the same procedure. After the cutting operation is completed, the equipment for cutting long objects is lifted onto the refueling platform, inspected, and then stored.

As explained above, the long object cutting device according to the present invention can be easily cut by the interaction between the pressing force of the pushing blade 68 by the cutting cylinder mechanism 4 and the bending force and tensile force by the gripping cylinder mechanism 2.3. Since a neutron measurement qp for disposal can be installed, there is no need for a push blade 68 with a sharp cutting edge as in the conventional case. Therefore, chipping or peeling of the cutting edge does not occur, and the life of the pushing blade 68 is extended, so the number of replacements of the pushing blade 68 is reduced, the working time is shortened, and the economical efficiency of the pushing blade 68 is also improved. Another effect is that workers can be protected from radiation exposure by shortening work time.

Although the above embodiment mainly describes the case where the present invention is applied to underwater cutting of a neutron A1 pipe for disposal, the present invention is not limited to this, and can be widely applied as a cutting device for cutting long objects underwater. It is possible.

〔Effect of the invention〕

The long object cutting device according to the present invention includes a gripping cylinder mechanism for fixing the long object to a main body frame that can be suspended from a wire rope or the like, and a cutting cylinder mechanism for pressing and cutting the long object. The gripping cylinder mechanism has a bending cylinder mechanism capable of moving the fixing point of the long object in the direction of the piston axis and bending the long object using the pressing cutting point as a fulcrum. The cutting ability can be improved without the need for a sharp push blade, thus extending the life of the push blade.In addition, the number of replacements of the push blade can be reduced, reducing work time and improving economic efficiency. There is an effect.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing an embodiment of a long object cutting device according to the present invention, FIG. 2 is a view taken along the line ■-■ in FIG. 1, and FIG.
FIG. 4, which is a view taken along the line ■-■ in the figure, shows a water pressure pump and a water supply and drainage system for supplying and discharging pressurized water to the above-mentioned long object cutting device. DESCRIPTION OF SYMBOLS 1... Main body frame, 2... Cylinder mechanism for upper grip, 3... Cylinder mechanism for lower grip, 4... Cylinder mechanism for cutting, 5.6... Cylinder for bending, 12°1
3...Press cylinder mechanism, 14.15...Cylinder, 18a, 18b, 19a, 19b->! Janda 9
．． 20a, 20b, 21 a, 21 b--... water penstock,
22゜23... Piston rod, 28.29... Pressing part, 30.31... Cylinder, 34.35... Cylinder chamber, 38.39... Water penstock, 40.41...
Piston rod, 44.45...Receiving part, 50...
Front cylinder, 51... Rear cylinder, 54a, 54
b, 63... Cylinder chamber, 55a, 55b... Hydraulic pipe, 56, 65° 66... Piston rod, 68...
・Push blade, 69... Blade holder, 70... Water pressure pump. Figure 3

Claims (1)

[Claims] 1. A main body frame that can be suspended from a wire rope or the like is provided with a gripping cylinder mechanism for fixing a long object and a cutting cylinder mechanism for pressing and cutting the long object; A long object characterized in that the bending cylinder mechanism has a bending cylinder mechanism capable of moving a fixed point of the long object in the direction of the piston axis and bending the long object using the press cutting point as a fulcrum. cutting equipment. 2. The long object cutting device according to claim 1, wherein the grasping cylinder mechanism is arranged in parallel above and below the cutting cylinder mechanism, and each has a pressing cylinder mechanism and a bending cylinder mechanism. . 3. The pressing cylinder mechanism has a pressing part that presses a long object by supplying pressure water to the cylinder chamber, and the bending cylinder mechanism grips the long object between it and the pressing part. 3. The long object cutting device according to claim 2, further comprising a receiving portion movable in the axial direction of the piston during cutting. 4. The cutting cylinder mechanism has a push blade that presses a long object by supplying pressure water to the cylinder chamber, and a blade receiver that cuts the long object between this push blade. A long object cutting device according to scope 1.