JPS5942839B2 - control rod drive exchanger - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a control rod drive unit exchanger for a boiling type nuclear reactor, and to a protection device for preventing collisions during replacement work in this exchanger.

Conventionally, in a boiling type nuclear reactor, the control rods that control the reactor's output and the power distribution within the reactor core are operated by a hydraulic control rod drive device (C, R, D) installed outside the reactor pressure vessel.
(!: is also abbreviated), and during periodic inspections, the control rod drive device that caused the problem was detected by the control rod, C,
Separate the R and D housings, transport them outside the containment vessel, and repair them.

Alternatively, a new control rod drive device is carried into the lower part of the reactor pressure vessel inside the containment vessel and reinstalled.

As described above, since a large number of workers are involved in the work of replacing control rod drive devices, there is a strong demand for remote control and automation from the standpoint of reducing radiation exposure and expediting replacement work. There is.

On the other hand, the lower part 5 of the reactor pressure vessel. In other words, in addition to about 190 control rod drive devices, the pedestal has about 60 neutral source area monitors (S).

R, M) The guide tubes of the intermediate region monitors (LR, M), the guide tubes of the local output monitors (L, P, R, M), and various neutron instrumentation devices are arranged in a complicated manner. R
,M,1. Each of the R and M guide pipes hangs long from the pressure vessel mentioned above, and a large amount of these cables hangs low.

Therefore, conventionally, when replacing the control rod drive device using a replacement machine, the control rod drive device was replaced by avoiding the low parts that held the S, R, and M guide tubes and the L-P, R, and M cable guide tubes. The device is moved horizontally while being held vertically, then rotated within the pedestal, held horizontally, and transferred to a trolley to be transported outside.

However, in the replacement work using the above-mentioned exchanger, if there are misoperations or various cables or equipment hanging down in unexpected places, the guide tubes of control rods etc. may collide with them and be damaged, or the periodic inspection period may be extended. This causes a decrease in the operating efficiency of nuclear power plants.

In view of the above-mentioned points, the present invention provides an exchanger for suspending a control rod drive device on a platform (turntable) carriage, and provides a detector using a charging conversion element in this exchanger.
This allows the equipment and various cables inside the pedestal to be detected during replacement work, preventing damage to the control rod drive system, and also shortening the period of periodic inspections and improving the operating efficiency of the nuclear power plant. The purpose of this invention is to provide a control rod drive exchanger.

Hereinafter, the present invention will be described with reference to an illustrated embodiment.

In FIGS. 1 to 3, reference numeral 1 indicates the control rod drive device 2.
This pedestal has an entrance 3 through which materials are brought in using a trolley (not shown). Inside the pedestal 1, a ring plate-shaped rail 4 is installed horizontally, and on this rail 4 is a platform. (Turntable) 5 is provided so as to be rotatable.

Further, a cart 6 is provided on the platform 5 so as to be movable in the horizontal direction, and a lifting device (also referred to as a rotating device) 7 is provided on the cart 6 so as to be rotatable around a support shaft 8. It is being

Furthermore, a pair of gripping rods 9 are provided in a part of this lifting device I, and the control rod driving device 2 extracted from the control rod driving device housing 10 can be freely attached to and detached from each of the gripping rods 9. It is designed so that it can be held easily.

On the other hand, at one end 7-ai of the lifting device T, a pair of arm rods 11 are rotatably mounted around a support shaft 12, and at the free end 11a of the arm rod 11, for example, An elastic disk 13 made of a soft synthetic resin material is provided so as to surround the upper part 2a of the control rod drive device 2 from the outside.

Further, a plurality of light emitters 14 are disposed in a ring shape on the lower surface of the elastic disk 13, and each of the light emitters 14 is an independent light emitting lamp 14 a = 14 b t
14c...14n (see Figure 3).

Further, a holding body 15 divided into two parts is provided directly below the light emitting device 14 and in a part of the raising/lowering device 7 so that it can be opened and separated from the control rod driving device 2. A plurality of light receivers 1 are provided on the upper surface of this holder 15.
6 is attached.

The light receiver 16 is provided facing the light emitter 14, and as shown in FIG. , 17c...17n select whether or not the light flux can be received, and each light receiving element 18a, 18b, 18c...18n converts the light flux into an electrical signal, Furthermore, each electric signal is judged by a judgment device 19a, 19b, 19c...19n.
and determines each received light, and this determination device 1
If 9a, 19b, 19c""19n is not receiving light, the determination device 19a.

The output signals of the trip devices 19b, 19C, . . . , 19n are transmitted to the trip device 20 to issue an alarm, and at the same time, the operation of the raising device 7, etc. is stopped.

Incidentally, in order to prevent malfunction, the trip device 20 can also be combined with an adjacent signal, and can start operating again when the light emitter 14 and light receiving plate 15 return to their normal positions. I'm starting to get it.

On the other hand, an electric motor 21 is provided near the support shaft 12 of the arm rod 11, and a worm wheel 22 is mounted on the output shaft of the electric motor 21.

Furthermore, this white ohm wheel 22 has a worm 23.
are in mesh with each other, and the worm 23 is mounted on the base 15a of the holder 15.

Therefore, as shown in FIG. 1, the control rod drive device 2 pulled out from the control rod drive device housing 10 is gripped by each gripping rod 9 of the lifting device 7, and the trolley 6 is moved to a predetermined position. In this process, when the elastic disk 13 collides with various cables or equipment hanging below the pedestal 1, it is distorted and deformed, and the light emitted from the light emitting lamp 14a of the light emitter 14 of the elastic disk 13 is Since the light beam comes off the filter 17a of the light receiver 16 and is not received, the trip device 20 is activated via the light receiving element 18a and the judgment device 19a to issue an alarm, as described above, and at the same time, the trip device 20 The operation is now stopped.

In this way, the replacement work can be safely performed using the exchanger without damaging the various cables, equipment, control rod drive device 2, etc. mentioned above.

On the other hand, when the trolley 6 moves to a predetermined position on the platform 5, the raising/lowering device 7 rotates about 90 degrees to the left around the support shaft 8 to hold the control rod drive device 2 horizontally.

By driving the electric motor 21, the arm rod 11 integrated with the elastic disc 13 is moved to the support shaft 12.
while rotating to the right around the worm wheel 22.
By slowly rotating the worm 23 that engages with the worm 23, the holder 15 is opened and separated from the drive rod drive device 2.

Next, each of the gripping rods 9 is released, and the control rods and drive device 2 are transferred to another truck (not shown) waiting at the entrance 3.
It is designed to be moved and carried out.

As described above, according to the present invention, the lifting device 7 of the control rod drive device 2 is provided on the trolley 6 of the platform 5, and the arm rod 11 is rotatably attached to one end of the lifting device 2. An elastic disc 13 formed to surround the upper part 2a of the control rod drive device 2 from the outside is provided on the arm rod 11, and a plurality of light emitters 14 are arranged around the elastic disc 13 facing downward. A holding body 15 located directly below the light emitting device 14 is provided so as to be opened from the arm rod drive device 2 in conjunction with the rotational movement of the arm rod 11. Since each light receiver 16 is attached to the body 15 so as to be located directly below each of the light emitters 14, there is no risk of collision with various cables and equipment hanging down when the trolley 6 and the lifting device I are moved. This eliminates the risk, not only shortens the period of periodic checkups, but also reduces the amount of radiation exposure and has a simple configuration.Furthermore, the light emitting device that is no longer needed can be incinerated, so it is possible to dispose of radioactive waste. Processing is also easy.

[Brief explanation of drawings]

FIG. 1 is a side view of a control rod drive exchanger according to the present invention, FIG. 2 is a perspective view showing only the essential parts of the present invention, and FIG. 3 is a diagram for explaining the operation of a detector incorporated in the present invention. It is a diagram. 1... petestal, 2... control rod drive device, 5...
・Platform, 6... Trolley, 7... Lifting device,
9... Grip rod, 11... Arm rod, 13... Elastic disk, 14... Light emitter, 15... Holder, 16... Light receiver, 21... Electric motor, 22... ...worm wheel, 2
3...Warm.

Claims (1)

[Claims] 1. A lifting device for the control rod drive device is provided on the platform trolley, an arm rod is rotatably provided at one end of the lifting device, and the upper part of the control rod driving device is enclosed in the arm rod from the outside. A plurality of light emitters are arranged facing downward around the elastic disc, and a holder positioned directly below each of the light emitters is linked to the rotational movement of the arm rod. 1. A control rod drive device exchanger, characterized in that the control rod drive device is provided with legs extending from the control rod drive device, and each light receiver is attached to the holder so as to be located directly below each of the light emitters.