JPS6384812A - Portable cutting device - Google Patents

Abstract

PURPOSE:To enable cutting with remote operation by providing a hold casing having a built-in clamp device, a rotary casing connected thereto, a means for turning the casing and the like, and mounting a disc cutter in the rotary casing. CONSTITUTION:A portable cutting device 6 is hung down, coupled to a workpiece 4 and secured thereto with a clamp device 8 built into a hold casing 7. Thereafter, a rotary casing 9 is turned and a disc cutter 13 is operated. In this case, the disc cutter 13 turns round the workpiece 4, rotating along a portion to be cut, and carries out a cutting process. Then, the securing of the cutting device 6 is released and this device 6 is lifted. The aforesaid operation is done under monitoring by a fiberscope 15 and chips generated during the cutting process are discharged outside via a chip aspirator 16. The titled device is capable of cutting a portion to be cut via remote operation.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cutting device, in particular for the replacement of internal parts of a control rod drive, e.g. This invention relates to a portable cutting device used at various times.

BACKGROUND OF THE INVENTION] As shown in FIG. 4, a control rod drive device 1 for a nuclear reactor protrudes above a cover body 2a of a reactor vessel 2, and a drive unit 3
This is to operate the i control rod (not shown) inside the reactor vessel 2 to control the output of the reactor. This aw rod drive device is W! At the lower part of the housing 4 which is closed and inside the drive part 3, a seal weld or canopy seal 5 is welded as shown in FIG. Therefore, when replacing the internal parts of the control rod drive bag W1 or repairing the seal weld, it is necessary to cut the seal weld.

However, this cutting has conventionally relied on manual work on site, and no equipment has been provided to perform the cutting mechanically. Therefore, since the work is performed in a radioactive environment, there is a need for a cutting device that can mechanically cut the seal weld by remote control.

In addition, when cutting the seal weld with a cutting device, the drive section 3 is removed from the control rod drive device 1, and the cutting bag ff (generally indicated by reference numeral 6 in FIG. 4) is inserted from the upper part of the control rod drive bag Wt1 into the housing 4. It is necessary to adopt a method of lowering the seal (as shown) and setting it at the position of the seal weld.

[Object of the Invention/Invention] Therefore, the object of the present invention is to make it possible to suspend and lower the control rod drive device from the upper part of the control rod drive device from which the drive part is removed to the position of the seal welding part, that is, to be able to transport it to the workpiece, It is an object of the present invention to provide a portable cutting device capable of cutting a seal weld or a part to be cut at a location by remote control.

[Means for Achieving the Object] For this purpose, the present invention includes a holding casing that is removably fitted to a workpiece and includes a gripping device, and a holding casing that is coaxially and rotatably attached to one end of the holding casing. The present invention provides a portable cutting device having a connected rotary casing, a rotating means mounted on the holding gauging for rotating the rotary casing, and a disc cutter mounted within the rotary casing.

[Operation: First, the portable cutting device of the present invention is suspended and fitted onto the workpiece, and the zero-order rotary gauging fixed to the workpiece is rotated using the gripping device built into the holding casing. When the disc cutter attached to the rotary casing is operated, the disc cutter rotates around the workpiece along the part to be cut and cuts the part to be cut.

After cutting, the cutting device is released from being fixed to the workpiece by the gripping device, and then the cutting device is lifted up.

[Embodiments] Next, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, in which the same reference numerals indicate the same or corresponding parts. Although the present invention will be described with reference to the case of cutting a canopy seal in the housing of a control rod drive device, it is applicable to other applications and is not limited to the embodiments.

FIG. 1 shows a partially cutaway view of the portable cutting device 6 according to the present invention.
) is suspended from the upper part of the control rod drive device 1 from which it has been removed onto the outer periphery of the housing (workpiece) 4, and is stopped at a predetermined position.

The cutting device 6 includes an upper holding casing 7 that is removably fitted into the housing 4 and contains a gripping device 8, and a lower rotating casing 9 that is coaxially and rotatably connected to one end of the holding casing 7. , a rotating means 14 mounted on the holding casing 7 for rotating the rotating casing 9 , and a disc cutter 13 mounted inside the rotating casing 9 .

The gripping devices 8 are provided at three locations so as to be able to come into contact with the circumferential surface of the housing 4, and grooves 8a are cut in the upper surface thereof.

Further, a housing 4 is provided near the lower end of the holding casing 7.
An annular gear 10 is provided to surround the gear 10, and a spiral protrusion 10a cut on the lower surface of the gear 10 fits into the groove 8a described above.

A drive motor 11 is mounted on the flange portion 7a of the holding cushion.
is installed, and a gear 11a provided at one end of its output shaft meshes with the gear 10 described above.

Therefore, by driving the drive motor 11, the gripping device 8 is moved radially inward along a guide (not shown) into engagement with the circumferential surface of the housing 4, and the cutting device 6 is moved into engagement with the circumferential surface of the housing 4. is fixed at a predetermined position where it hits the stepped portion 4a of the housing 4.

An annular sleeve 7b hangs down from the flange portion 7a of the holding casing 7 so as to surround the aforementioned gripping device 8, and the rotary gauging 9 is rotatably supported with respect to the annular sleeve 7b. In order to perform the rotation, a gear (
The rotation means) 14 is turned off, and the drive motor 1 described above
1, a drive motor (not shown) having an output shaft with a gear is attached to the rotating casing 9, and the gear (not shown) meshes with the gear 14. Therefore, by operating a drive motor (not shown), the rotating casing 9 can be rotated in a predetermined direction.

Inside the rotating casing 9, a disc cutter 13 and various related devices are installed. That is, since the mechanism itself of each device may be well-known, to briefly explain, in FIGS. 1 and 3, 15
16 is a fiber scope for monitoring the operating state of the disc cutter 13, one end of which extends to the vicinity of the disc cutter 13, and the other end extending to a remote position (not shown). A chip suction device has one end extending close to the disc cutter 13 and the other end connected to a suction device (not shown) to suck up chips generated by the cutting surface. An angle adjustment shaft for adjusting the inclination angle of the rotating plane of the disc cutter 13 so that A radial feeding device for the disc cutter 13, which includes a plate 19c that is threaded onto the screw shaft 19b and cooperates with the aforementioned plate 17a. 20 is connected to the drive system of the disc cutter 13, which includes a telescoping joint 21, and is connected to the drive system of the disc cutter 13, which is connected to the drive system of the disc cutter 13, which includes a telescopic joint 21, and is connected to the drive system of the disc cutter 13, which includes a telescopic joint 21. It is a cutting motor that operates the cutter 13, and 22 is a fine movement feeder that is attached to the plate 17a and finely adjusts the disc cutter 13 in the radial direction. In addition, the above-mentioned devices 15 to 17 and 19 to 22 are equipped with a motor 18m.
, gears 18b, 18c, screw shaft 18d and plate 18
It is movable in the vertical direction by a vertical feeding device 18 including e.

Next, to explain the actual operation of the above-mentioned portable cutting device 6, first, the cutting device 6 is suspended from the upper part of the control rod drive device 1 from which the drive section 3 (FIG. 4) has been removed, and the cutting device 6 is held therein. After the casing 7 is brought into contact with the stepped portion 4a of the housing 4, the gripping device 8 is activated to fix the cutting device 6 to the housing 4. In order to cut the canopy seal 5, before suspending the cutting device 6, as shown in FIG. After the cutting device 6 is fixed at a predetermined position in this way, the disk cutter 13 is moved from the initial position A to the position raB suitable for cutting by the vertical feed device 18 while observing with the fiberscope 15.
and then moved by the radial feed device 19 to position T1. Move to C. Then, while similarly observing with the fiberscope 15, the cutting motor 20 rotates the disc cutter 13, and the fine movement feeder 22 moves the disc cutter 13 in the cutter diameter direction to start cutting the seal weld 5. Ru.

When the cutting operation starts, a drive motor (not shown) attached to the rotary casing 9 is activated, and a gear (not shown) attached to the output shaft of the drive motor is connected to a gear 14 attached to the holding casing 7 (fixed side). Because of the meshing, the rotary casing 9 is rotated in a predetermined direction, the disc cutter 13 rotates together with the rotary casing 9 around the seal welded portion 5, and when the cutting operation is completed, the rotation is stopped.

After the cutting operation is completed, the disk cutter 13 is returned to the old position A by performing the reverse operation described in connection with FIG. 2, and the gripping device 8 shown in FIG. can be extracted upward from the control rod drive device 1.

Each of the above operations is carried out while being monitored by the fiber scope 15 shown in FIG. 1, and chips during cutting are discharged outside the machine by a chip suction device 16.

[Effects of the Invention] As described above, according to the present invention, from the upper part of the workpiece (in the embodiment, the housing of the control rod drive device from which the drive part has been removed) to the position of the seal welding part, which is the part to be cut, A completely new portable cutting device is provided that can be suspended and lowered and can cut a part to be cut at that position by remote control.

In a preferred embodiment, the cutting device is generally cylindrical to avoid interference with adjacent control rod drives during lowering.

In addition, in a cutting device with a fiber scope,
A series of cutting operations can be performed remotely while being monitored, and if the machine is equipped with a chip suction device, chips generated during the cutting operation can be discharged to the outside of the machine.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of a portable cutting device according to the present invention, FIG. 2 is a diagram illustrating the position adjustment operation of the disc cutter with respect to the seal weld, and FIG.
A perspective view illustrating various drive systems of the disk cutter in the cutting device shown in FIG. 1, and FIG. FIG. 5, a perspective view showing the portable cutting device, is an enlarged view of region V in FIG. 4. 4... Workpiece (housing) 6... Portable cutting device 7... Holding casing 8
...Gripping device 9...Rotating casing 13
... Disc cutter 14 ... Rotating means (gear)
Figure 1

Claims (1)

[Claims] A holding casing that is removably fitted to a workpiece and has a built-in gripping device; a rotating casing that is coaxially and rotatably connected to one end of the holding casing; and a rotating casing that is attached to the holding casing and that supports the rotating casing. A portable cutting device comprising a rotating means for rotating and a disc cutter mounted within the rotating casing.