JPH02224912A - Cable cutter - Google Patents

Abstract

PURPOSE:To enable cutting in a short time and surely without accompanying any danger by feeding a high pressure work fluid to a driving cylinder and moving the push blade fixed to a driven piston in the cable direction, in case of cable cutting of the instrumentation guide pipe, etc., of an atomic furnace at emergency time. CONSTITUTION:In cutting a cable for instrumentation inside a furnace center urgently by the abnormality of an atomic furnace, a high pressure water is fed to the upper part space of a piston 4 via a water feeding pipe 18 by remote control. A push blade 3 becoming integral via a piston 4 and square shaft 14 is subjected to dividing to cut a cable 1 and a compensation cable 7 thereof by squashing them simultaneously. The cut piece and push blade 3 are received by a seat plate 10 and the heldup water is discharged from a drain pipe 19. The complete cutting of the cable 1 is detected and confirmed automatically by the cut of the compensation cable 7. In case of a high pressure water feeding system being out of order, the push blade 3 can be subjected to diving similarly to the above by the operation of a manual device 6, namely turning a handle bar 24 manually.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a cable cutter for cutting a couple such as an instrumentation guide pipe in an emergency in a boiling water nuclear reactor, and particularly for cutting a couple such as an instrumentation guide pipe in an emergency. This invention relates to a cable cutter that can reliably perform a cutting operation without using it, is easy to handle, and can be constructed in a small size.

(Prior art) Generally, in boiling water reactors, mobile in-core instrumentation (
It is an abbreviation for TIP, and is hereinafter referred to as TIP. ) is provided. This TIP is provided to detect gamma rays in the reactor for controlling the nuclear reaction within the reactor core, and to incorporate the detection signal into the main control circuit to perform automatic control of the reactor.

The TIP is installed in a TIP cable from the core to the central control room, and is supported by a TIP guide pipe from the exit of the reactor containment vessel to the medium-heat control room. The TIP guide tube is a steel tube with a diameter of about 10 mm and a wall thickness of about 1 thick.

The TIP cable inside the VIP guide tube is guarded with a spring wire and coated with a rough coating.

The TIP guide tube 13 and the TIP cable are replaced one after another after a predetermined period of time due to deterioration or life of the internal detection element. During this replacement work, a winding device is separately prepared and an operation for winding up the couple is performed. However, in the event that this winding device malfunctions or a sudden accident occurs within the reactor containment vessel, cables containing highly radioactive detection elements cannot be left unattended. Cables, etc. are urgently cut, the opening of the TIP guide pipe outlet of the reactor containment vessel is blocked, and the couple is isolated.

Conventionally, as a device for cutting cables, etc., an explosion valve filled with explosives for cutting the IP guide tube was installed at the exit of the TJ l) guide tube in the reactor containment vessel in advance to reduce the drying force of the explosive in an emergency. The TIP guide tube and the TIP couple were cut by pressing the pushing blade with a single-edged chevron that serves as a driving force, and the 17i10 end of the cable on the reactor containment vessel side was closed with the side surface of the pushing blade.

(Problems to be Solved by the Invention) Conventionally, in order to cut cables, etc., explosive valves have been used which use explosives as driving force to instantly cut the cables. Explosion valves require the use of explosives, and procedures such as acceptance of explosives, maintenance, qualifications for handling supervisors, and handling procedures are complicated, requiring a great deal of effort during installation, regular maintenance, and inspection. Especially in the event of an emergency, the Ministry of Works does not have enough time to select a person in charge of handling explosives, which may make it difficult to respond quickly. Also,
Since gunpowder is an explosive, it was necessary to take precautions against danger, such as taking measures to prevent the sanbatsuha from scattering into the surrounding area.

Therefore, we have proposed a motor-driven cable cutter that can be used to issue remote disconnection instructions using electrical signals in emergencies and is easy to maintain and inspect. In this case, the emergence of a cutting device that can select an appropriate motor from among various motors, secure the necessary torque and power, and complete the cutting in a relatively short period of time, such as one minute. It was desired. However, motor-driven cable cutters require a high-altitude horn motor as the drive source, and have the drawbacks of a larger transmission mechanism, cumbersome operation, and poor start-up performance.

The present invention has been made in consideration of the above-mentioned circumstances, and anyone can operate it without using explosives such as gunpowder in an emergency, and it can be used in a short time and reliably as a guide tube such as a TIP. To provide a cable cutter capable of cutting cables with four or more cables, small in size, easy to maintain and inspect, and non-hazardous.

[Structure of the invention]

(Means for Solving the Problems) The cable cutter according to the present invention includes a base that holds a cable to be cut, a pusher blade arranged to face the cable, and a piston to which the pusher blade is fixed in the direction of the cable. It is characterized by being equipped with a drive cylinder which is housed so as to be movable forwards and backwards and drives the piston with high-pressure working fluid, and also equipped with a manual pushing device which manually moves the piston to which the pusher blade is fixed to move forward and backward in the direction of the cable. -Zuru.

Also, when cutting the cable, the same 11. It is preferable to use one in which the couple is cut in the Y direction and a compensating wire is continuously inserted in the axial direction of the couple to detect when the cutting operation is completed.

(Function) According to the cable cutter having the above configuration, in an emergency, a working fluid such as high pressure water is supplied to the drive cylinder to drive the piston, and the push blade fixed to the piston moves in the direction of the cable. , the cable can be cut instantly.

Furthermore, even if the system for supplying high-pressure working fluid fails and the drive cylinder does not operate, the cable can be reliably cut by manually operating the manual pressing device.

Furthermore, if a cable in which a compensating wire is inserted continuously in the axial direction is used, the compensating wire will be cut at the same time when the cable is cut, and the completion of the cutting operation will be detected by cutting the compensating wire. This makes it easier to check and ensure reliable cutting operations. .

According to the couple cutter of the present invention, the sea urchin
- When cutting the pull, unlike in the past, explosives are not used as a driving force source, so even workers who are not qualified to handle explosives can quickly perform the cutting process.

In addition, since a high-pressure working fluid is used as the driving force source and there is no need for a person like the conventional cutter, the structure of the cutter is simple and handling is very easy.

(Embodiment) Next, an embodiment of the present invention will be described with reference to the accompanying drawings 1 to 5. FIG. 1 is a sectional view showing an embodiment of a cable cutter according to the present invention.

In other words, the cable cutter according to this embodiment includes a base 2 that holds the goople 1 to be cut, a pusher blade 3 arranged to face the cable 1, and a piston 4 with the pusher blade 3 hardened in the direction of the cable 1. A manual suppressing device 6 is provided with a drive cylinder 5 which is housed in a movable direction and moved back and forth, and which drives the piston 4 with high-pressure working fluid, and a manual suppression device 6 which manually moves the piston 4 to which the pusher blade 3 is fixed to move back and forth in the direction of the cable 1. Established (consisted of).

The cable 1 is cut in parallel with the cut #I of the cable 1, and a compensating wire 7 is continuously inserted in the axial direction on the lower surface of the cable to detect the completion of the cutting operation. The compensation wire 7 forms a loop-shaped detection circuit in which a display lamp (not shown) is provided, for example, and when the compensation wire 7 is cut together with the cable 1, the display lamp lights up to indicate that the cutting work has been completely completed. configured to do so.

Further, the cable 1 is inserted through the base 2 through the sleeve 8. A square hole 9 is formed in the center of the base 2, through which the straightening blade 3 moves up and down, and the opening at the lower end of this square hole 9 receives the pushing blade 3, as shown in FIGS. 1 and 3. A seat plate 10 ( ) is fastened and fixed by poles 1-11. Furthermore, as shown in FIG. It is fixed by doing this.

Further, the pusher blade 3 is fixed to the lower surface of the piston 4 disposed in the drive cylinder 5 via a square shaft 74, and...
The square shaft 14 and the pusher blade 3 are configured to move up and down within the square hole 9 of the base 2.

The drive cylinder 5 is fitted onto the upper part of the base 2 and tightened with a tightening pole]・
J at 15 is fixed to the base 2.

In addition, a water supply port 16 and a drain port 17 are provided in the space on the upper and lower surfaces of the piston 4, respectively.
A water supply pipe 18 and a drain pipe 19 for supplying and discharging high-pressure water as a high-pressure working fluid are connected to the drain port 17, respectively. The water supply pipe 18 is connected to a discharge port of a high-pressure water pump that sucks water from a water tank (not shown), and the drain pipe 19 is connected to the water tank. As the high-pressure water pump, it is recommended to use a proportional pump that pressurizes a large diameter diaphragm with air and pushes water out of a narrow discharge port.

The water supply pipes 18 and υ1 water pipes 19 are constructed so that high-pressure water flows in the opposite direction when the switching valve is operated. Further, in order to prevent high pressure water from leaking from the fitting surface between the base 2 and the drive cylinder 5 and the sliding surface between the drive cylinder 5 and the piston 4, an O-ring 20a is provided.

20b is attached.

On the other hand, as shown in FIGS. 1 and 2, the manual suppression device 6 includes a spindle 21 that is slidably inserted in the upper part of the drive cylinder 5 in the axial direction, and is fixed to the upper end of the spindle 21 with a tightening nut 22. boss 23 and boss 2
3 on the side of boss 23 so that they are facing each other.
(It consists of a pair of handle rods 24 that are pulled together.) An O-ring 20c is attached to the sliding surface between the spindle 21 and the drive cylinder 5 to prevent leakage of high-pressure water.

An increased diameter portion 25 is formed in the intermediate portion of the spindle 21, and this I11 diameter portion 25 comes into contact with the upper surface of the inner wall of the drive cylinder 5, thereby defining the upper limit of the rise of the spindle 21.

A male thread 26 is formed at the lower end of the spindle 21, and this male thread 26 is screwed into a female thread 27 formed at the center of the piston 4 and the square shaft 14, as shown in FIG.

Further, as shown in FIG. 4, circumferential grooves 28a and 28b are formed on the outer peripheries of the piston 4 and the square shaft 14, into which sealing materials such as O-rings are fitted.

Further, as shown in FIG. 5, the outer peripheries of the pusher blade 3 and the square shaft 14 are formed into a prismatic shape, and are accommodated in a square hole 9 formed in the base 2 in a sliding manner. Therefore, even when the handle bar 24 is rotated, rotation of the push blade 3 and the square shaft 14 around the central axis of the spindle 21 is restricted.

Next, the functions and effects of the cable cutter according to this embodiment will be explained.

If an abnormality occurs in the reactor or the winding device that winds up the TIP breaks down during cable replacement, the detector at the tip of the TIP may get inside the TIP drive device, so the TIP cable should be removed immediately. It will be necessary to cut it off and close the ends. This cutter supplies high-pressure water to the upper space of the piston 4 via the water supply pipe 18 of the cable cutter by remote control. Then, the pushing blade 3 integrated with the piston 4 via the square shaft 14 suddenly descends, crushing the cable 1 and the compensation wire 7 interposed on the lower surface of the couple 1 almost simultaneously, and in the crushed state, the cable 1 and the The compensation wire 7 is further cut by the push blade 3. The cut piece and the cutting edge of the pushing blade 3 are received and held by the seat plate 10.

The complete disconnection of the cable 1 is automatically detected by the disconnection of the compensation wire 7 cut in step 11), and the indicator lamp provided in the detection circuit is lit.

The water remaining in the space below the piston 4 is returned to the water tank through one drain pipe.

On the other hand, if a failure occurs in the high-pressure water supply system and high-pressure water cannot be supplied to the upper surface of the piston 4, the attached manual suppression device 6 can be operated to quickly disconnect the cable 1 manually. . That is, by manually rotating the handle bar 24, the push blade 3 is moved in the direction of the cable 1 by the screw action of the piston 4 screwed into the male thread 26 of the spindle 21 and the female thread 27 of the square shaft 14. However, it is also possible to cut the cable 1 and the compensation wire 7 at the same time in a push-cut manner. Therefore, reliability of the cutting operation can be increased.

According to the cable cutter of this embodiment, the driving force for cutting is provided by a driving cylinder 5 driven by high-pressure water.
Third, it is not as large as a conventional horn pull cutter that uses a drive motor, and is compact and easy to handle. Especially since it does not use explosives such as gunpowder,
Not only the person in charge of handling explosives but also all workers can quickly perform the cutting process, and delays in the cutting process can be prevented.

Furthermore, even if an abnormality occurs in the high-pressure water supply system that drives the drive cylinder 5 and the pusher blade 3 cannot be driven remotely, the pusher blade 3 can be moved by manually operating the manual pusher 6.
can be moved in one direction of the cable, and the cable 1 can be cut easily, quickly and reliably.

Furthermore, if a cable 1 in which a compensating wire 7 is continuously interposed in the axial direction is used as the cable 1, the compensating wire will be cut at the same time when the cable 1 is cut, and the cutting operation will be completed by cutting the compensating wire. Since it is detected, it is easy to check the cutting status.

After cutting cable 1, inspection and maintenance of the winding device will begin, but at this point, the highly activated TIP detector part has not accumulated in the device, so the restoration work can be carried out safely. ′? I- can do it.

In addition, when using the manual pressing device 6, the handle bar 2
4 in the opposite direction to return the push blade 3 to its initial position. Further, when the manual pressing device 6 is not used, the return operation of the pusher blade 3 is performed by gradually supplying high-pressure water to the drain pipe 19 and adjusting the raised position of the pusher blade 3.

〔Effect of the invention〕

As explained above, according to the cable cutter according to the present invention, in an emergency, by supplying working fluid such as high-pressure water to the drive cylinder and driving the piston, the push blade fixed to the piston moves in the direction of the cable, can be cut instantly.

Furthermore, even if the system for supplying high-pressure working fluid fails and the drive cylinder does not operate, the cable can be reliably cut and covered by manually operating the manual pressing device.

Furthermore, if a cable in which a compensating wire is inserted continuously in the axial direction is used, the compensating wire will be cut at the same time when the cable is cut, and it will be detected that the cutting operation has been completed. This makes it easier to check the cutting status, allowing for more reliable cutting operations.

As described above, according to the present invention, it is no longer possible to use explosives as a driving force source when cutting cables, as in the past.
In addition, even workers who do not have the qualifications of being in charge of handling explosives can quickly take amputation measures.

In addition, high-pressure working fluid is used as the driving force source, and conventionally 1J,
Since the cutter does not use a large motor or the like, the cutter is composed of parts and is very easy to handle and operate.

Figure M1 is a cross-sectional view showing an embodiment of the cable cutter according to the present invention, Figure 2 is a plan view as viewed from the ■■ arrow in Figure 1, and Figure 3 is a bottom view as viewed from the ■-■ line in Figure 1. 4 is an enlarged front view of the push blade and the piston, and FIG. 5 is a bottom view taken along arrow V-■ in FIG. 4.

1... Cable, 2... Base, 3... Push blade, 4
... Piston, 5... Drive cylinder, 6... Manual pressing device, 7... Compensation wire, 8... Sleeve, 9...
...Square hole, 10... Seat plate, 11... Bolt, 12.
...Mounting flange, 13...Mounting hole, 14...Square shaft, 15...Tightening bolt, 16...Water inlet, 17...
・Drain port, 18... Water supply pipe, 19... Drain pipe, 20
a, 20 b, 20 c-0-IJ>g,
21...Spindle, 22...Tightening nut, 23.
...Boss, 24...Handle bar, 25...Increased diameter part,
26...Male thread, 27.I thread, 28a, 28b...
・ZhoufM.

[Brief explanation of the drawing]

Claims (1)

[Claims] 1. A base that holds the cable to be cut, a pusher blade arranged to face the cable, and a piston to which the pusher blade is fixed are housed so as to be movable in the direction of the cable, and are cut by high-pressure working fluid. A cable cutter comprising: a drive cylinder for driving a piston; and a manual pressing device for manually moving the piston to which the pushing blade is fixed forward and backward in the direction of the cable. 2. The cable cutter according to claim 1, further comprising a compensating wire that is continuously inserted in the axial direction of the cable to be cut at the same time as the cable is cut and to detect the completion of the cutting operation.