JPS61286796A - Exchanger for driving mechanism of control rod - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a control rod layer A machine replacement device for a nuclear reactor, and in particular to a control rod that enables reliable positioning of the device during replacement by remote control. The present invention relates to a drive mechanism exchange device.

[Technical background of the invention]

In general, during periodic plant inspections of nuclear power plants, approximately 20% of the control rod section 1 [structure (hereinafter referred to as
(abbreviated as CRD) is replaced.

Conventionally, this CRD replacement work has been carried out inside a pedestal where radiation m is relatively high, so in order to reduce the exposure, it has been mechanized as much as possible to enable remote control.

Conventionally, as such a CRD replacement neck, figures 8 to 1 have been used.
There is one with the configuration shown in Figure 1. That is, in J5, a rail 3 is laid in a ring shape along the inner wall surface of the pedestal 2 below the reactor pressure vessel (hereinafter abbreviated as RPV) 1, and a platform 4 is rotatably placed on this rail 3. ing.

A traveling carriage 6 that can travel in the radial direction is mounted on a rail 5 provided on the platform 4. An arm 8 that can swing around a horizontal bin 7 as a fulcrum is attached to the traveling trolley 6. This arm 8 is equipped with an elevating support table 10 that can be moved by a chain 9. The lifting support table 10 has mounting bolts 1 for mounting the CRD 13 in the CRD housing 12 provided at the bottom 11 of the RPVI.
The structure is such that a bolt [[16] with a built-in wrench 15 for tightening, loosening, etc. 4 can be mounted. That is, the bolt detacher 16 is transferred from the bolt detacher stand m17, which is freely movable below the traveling carriage 6, to the elevating support stand 10. In addition, the platform 4, the traveling platform I! 6. Position detectors (not shown) are provided to detect the movement m of each lifting support table 10.

For example, CRD1 to be installed or removed.
3 position coordinates (θnibrat home 4 rotation direction, R:
The traveling direction of the traveling trolley 6 (Z: the vertical direction of the vertical support platform 10) is stored in a computer (not shown), and the current position (θ', R', Z') detected by the position detector is stored.
Positioning to match the stored coordinates (θ R22) is performed by remote control.

[Problems with background technology]

In actual alignment to the CRD 13, it is necessary to align the multiple wrenches 15 of the bolt detacher 16 and the mounting bolts 14 of the CRD housing 12.

However, in the conventional CRD exchange device, the detector cannot directly detect alignment between objects. In other words, the alignment to the CRD plane coordinates (θ, R> is performed by the traveling cart 6 and the platform 4, and the alignment between the target CRD 13 and the elevating support base 10 is performed indirectly. Vibrations occur during the lifting and lowering operations of the support platform 10, making remote control cumbersome and making accurate positioning difficult.For this reason, final positioning must rely on visual confirmation by a worker on the platform 4. There are cases.

For example, when removing the CRD 13, it may be necessary to visually check the final alignment of the wrench 15 of the bolt detacher 16 and the mounting bolt 14 of the CRD housing 12 as shown in FIG.

Further, when installing the CRD 13, it may be necessary to visually check the final alignment of the mounting bolt 14 as shown in FIG. 10 and the bolt hole 19 of the seven flange portions 18 of the CRD housing 12. Furthermore, as shown in FIG. 11, when inserting the CRD 13 into the CRD housing 12, it may be necessary to visually check the final alignment between the CRD 13 and the CRD housing 12.

Such visual inspection by a worker inside the pedestal 2 reduces work efficiency due to the lack of accuracy. Also, platform 4
The height from the top to the flange portion 18 of the CRD housing 12 is large, for example, about 2.5 m, and the work is difficult because a large number of CRDs 13 are arranged closely together.

(Object of the invention) The present invention has been made in view of the above circumstances.
It is an object of the present invention to provide a control rod drive mechanism replacement device that can easily and reliably perform final alignment to the CRD or CHD housing during D replacement work, and can effectively improve work efficiency.

(Summary of the Invention) In order to achieve the above object, the present invention includes a platform rotatably installed in a pedestal below a reactor pressure vessel, a traveling carriage mounted on the platform in a freely movable manner, and a An arm swingably attached to the traveling truck, and an elevating support provided on this arm so as to be able to rise and fall to support the control rod layer 17+ mechanism and the 1.lJ m rod drive mechanism mounting bolt removal machine. In the control rod drive mechanism exchange device equipped with a control rod drive mechanism, a laser oscillator is attached to the lifting support and the bolt removal machine as a means for positioning the lifting support and the bolt removal machine during replacement, and a laser oscillator is attached to the arm. Attach a laser receiver to detect the laser emitted from the control rod layer fL.
The present invention is characterized in that the l1 mechanism housing is provided with a mirror atR that reflects the laser emitted from the laser oscillator toward the laser receiver.

(Embodiment of the Invention) Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 to 7.

n F pressure vessel (RPV) 20 (7) bottom 21 tlJ
A large number of CRD housings 23 to which rod drive mechanisms (CRD) 22 are attached are arranged at equal pitches. CRD22 is
The lower end 7 flange portion 24 is fixed to the flange portion 25 of the CRD housing 23 by a plurality of mounting bolts 26.

A ring-shaped rail 29 is installed along the inner wall surface of the pedestal 27 below the RPV 20 using a support member 28. A traveling cart 32 that can run in the radial direction is mounted on the upper part of a platform 30 that is rotatably installed on the rail 29 via a rail 31. This running trolley 32
An arm 34 is attached to the arm 34, which can swing between a vertical position and a horizontal position using a horizontal bin 33 as a fulcrum. An elevating support base 36 is attached to the arm 34 via a chain 35 and is movable up and down along the arm 34.

This elevating support table 36 has a substantially U-shaped frame shape, and can support the CRD 22 therein, and can also mount a bolt attachment/detachment machine 38 for tightening and loosening the mounting bolts 26 on its upper part.

Note that a clamp 37 is attached to the arm 34 so as to be able to grasp the middle portion of the CRD 22. In addition, bolt attachment/removal machine 3
8 has a plurality of wrenches 39 at its upper end, and in order to align the wrenches 39 with the mounting bolts 26, the upper end of the bolt detacher 38 is rotatable.

In addition, as shown in FIG. 1, a bogie rail 40 is horizontally suspended from the lower part of the platform 30 by a support beam 41,
A bolt attachment/detachment machine 38 is placed on this truck rail 40 via a bolt attachment/detachment truck 42. By moving the porto l112 landing cart 42 towards and away from the arm 34,
The bolt attachment/detachment device 38 is attached to and detached from the elevating support base 36.

Although not shown, the platform 30 and the traveling trolley 3
2. A detector is provided for each of the lifting support tables 36 to detect the movement of the lifting support table 36. This position detector enables alignment to pre-stored coordinates (rotational direction of the platform 30, running direction of the traveling carriage 32, and lifting direction of the lifting support base 36). 'By the way, laser oscillators 43 and 44 are attached to the lifting support table 36 and the bolt removing machine 38, respectively, facing upward. The arm 34 also includes each laser oscillator 43.
a laser receiver 46 that receives the laser emitted from 44;
is attached via a bracket 47. This laser receiver 46 has a laser receiving section 45 at its upper end. In the flange portion 25 of the rough CRD housing 23,
A mirror mechanism 49 is provided via a support ring 48. This mirror mechanism 49 reflects the laser emitted from the laser oscillators 43 and 44 to the laser receiver 46. As shown in FIG. 177, the position where the laser receiver 46 senses the laser from the laser oscillator 43, 44 reflected by the mirror machine W149 is determined in advance at the position where the mounting bolt 26 and the wrench 39 match and the position where the lifting support The stand 36 and the CRD housing 32 are set in a matching position.

Next, the positioning action of the CRD exchange device will be explained.

First, the alignment of the wrench 39 of the bolt JB2W338 and the mounting bolt 26 when removing the CRD 22 will be described with reference to FIGS. 2 and 3.

Initially, without the bolt attachment/detachment device 38 being mounted on the lifting/lowering support base 36, the traveling carriage 22 and the platform 30 are aligned with respect to the memorized coordinates using a position detector (not shown). Next, the POL-1 detacher 1138 is mounted from the bolt detacher truck 42 onto the lifting support stand 36, raised along the arm 34, and stopped at a predetermined position. In this state, from the laser oscillator 43 attached to the lifting support 36,
- oscillates. The laser is reflected by the mirror mechanism 49,
When detected by the laser receiver 46 of the arm 34, the alignment between the 4111m support base 36 and the CRD 22 is completed. Note that if the laser receiver 46 does not detect the laser, the traveling carriage 32 and platform 30 may be inched (
(fine movement) and move it until it is detected.

Next, the wrench 39 of the bolt I112 and the mounting pin 38 are aligned with the mounting pole I.26. In this case, while emitting a laser from a laser oscillator 44 attached to the bolt detacher 38, a remote control room performs rotation inching of the bolt detacher 38.Laser receiver 46
When the radar reflected by the mirror mechanism 49 is detected, the turning inching operation of the bolt detacher 38 is stopped. When the alignment between the wrench 39 of the bolt detacher 38 and the mounting bolt 26 is completed through the above operations, the bolt detacher 38 is raised via the elevating support base 36, and the CR
After the D22 is brought into close contact with the flange portion 24, the process moves to a step of loosening the mounting bolts 26.

Further, in the case of mounting the CRD 22, the mounting bolts 26 and the bolt holes of the flange portion 25 of the CRD housing 23 are aligned, and this operation is the same as described above.

Next, the alignment of the CRD 22 and the CRD housing 23 when installing the CRD 22 will be explained with reference to FIGS. 4 and 5.

First, the platform 30 for the memory coordinates (θ, R)
After aligning the traveling trolley 32 with the arm 34
The elevating support table 36 on which the CRD 22 is mounted is raised along the line and stopped at a predetermined position.

In this state, the laser oscillator 43 of the elevating support table 36 emits a laser beam. When the laser receiver 46 attached to the arm 34 detects the laser reflected by the mirror mechanism 49, the alignment between the elevating support base 36 and the CRD housing 23 is completed. In addition, laser reception! If the fi 46 does not detect the laser, it performs an inching operation on the traveling trolley 32 and platform 30 while monitoring the monitor in the remote control room, and moves to the position where the laser is detected.

After the alignment is completed, the elevating support table 36 is raised and the CRD 22 is inserted into the CRD housing 23.

〔Effect of the invention〕

As described above, according to the present invention, laser oscillators are attached to the 4-drop support stand and the bolt l112 landing machine, and the lasers emitted from these laser oscillators are attached to the arm. By sensing through the reflection effect of the mirror device in the rod drive mechanism housing, it is now possible to directly align the objects, so there is no need to rely on visual confirmation by the operator, and the final alignment work can be done remotely. It can be operated accurately and easily.

Furthermore, since the laser receiver is attached to the arm and the mirror mechanism is provided in the CRD housing, the overall configuration is compact, and since a laser is used, reliability is high.

[Brief explanation of drawings]

Figures 1 to 7 show one embodiment of the present invention, with Figure 1 being a schematic front view and Figure 2 showing the control rod drive mechanism in a removed state.
Figure 3 is a front view of the main part, Figure 3 is a side view of Figure 2, Figure 4 is a front view of the main part showing the installation status of the υ control rod eta structure, Figure 5 is a side view of the main part of Figure 4, and Figure 5 is a side view of the main part of Figure 4. Figure 6 is an enlarged sectional view taken along the line Vl-Vl in Figure 4, and Figure 7 is a schematic diagram showing the laser propagation path.
Fig. 8 to Fig. 11 show a conventional example, Fig. 8 is a schematic front view, Fig. 9 is a front view of main parts, Fig. 10 is a front view showing a state in which the mounting is removed, and Fig. 11 is a state in which the CRD is replaced. FIG. 22... Control rod drive machine HA (CRD), 23...
Control rod drive mechanism housing, 26...Mounting bolt, 27...Pedestal, 29...Rail, 3
0...Platform, 32...Traveling trolley, 34.
... Arm, 36... Lifting support base, 39... Wrench, 43, 44... Laser oscillator, 46... Laser receiver, 49... Mirror i structure. Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 Figure 9 Figure 10

Claims (1)

[Claims] A platform is rotatably installed in the pedestal below the reactor pressure vessel, a traveling trolley is mounted on the platform to be able to travel freely, an arm is swingably attached to the traveling trolley, and a platform is attached to the arm that can be raised and lowered. In the control rod drive mechanism replacement device, the control rod drive mechanism is equipped with an elevating support base that supports the control rod drive mechanism and supports a bolt attachment/detachment device for attaching the control rod drive mechanism. As a means for positioning the machine, a laser oscillator is attached to the lifting support stand and bolt attachment/removal machine, a laser receiver that detects the laser emitted from the laser oscillator is attached to the arm, and a laser receiver that detects the laser emitted from the laser oscillator is attached to the control rod drive mechanism housing. 1. A control rod drive mechanism exchange device comprising: a mirror mechanism for reflecting the laser beam toward the laser receiver.