JPH0213759B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention remotely automates the disassembly and cleaning work of the control rod drive mechanism (hereinafter simply referred to as CRD).
This invention relates to a grapple device as a disassembly mechanism of a CRD disassembly and cleaning device.

Conventional CRD disassembly and cleaning work is carried out manually by workers in the atmosphere, which has the disadvantage of exposing workers to extremely high doses of radiation.
In particular, the CRD disassembly and cleaning work related to the present invention was carried out manually using a simple lift, which should definitely be improved from the standpoint of radiation exposure and work safety.

An object of the present invention is to provide a CRD disassembly and cleaning device that remotely and automatically disassembles and cleans a CRD.
It is an object of the present invention to provide a grapple device equipped with a holding mechanism and a lifting mechanism for sequentially handling a long cylindrical part according to each step of disassembly and cleaning.

The present invention will be explained below with reference to one embodiment of the present invention.

Figures 1 and 2 show the configuration of the CRD disassembly and cleaning equipment. The CRD decomposition and cleaning equipment consists of a decomposition and cleaning tank 1,
It is composed of a moving cart 2, a grapple device 3, a pulling clamp unit 4, a roller chain 5, and a drive motor 6. The decomposition and cleaning tank 1 is filled with water and is constantly mounted on a moving trolley 2.
CRD7 is submerged in water. The movable cart 2 is moved via a roller chain 5 by a drive motor 6.

The disassembly of CRD7 is carried out using the movable trolley 2 as described below.
This is done by moving the CRD 7 placed on the tube and grabbing it with the pulling clamp unit 4, and moving the moving cart 2, and the pulled out CRD tube is gripped by the grappling device 3 of the present invention.

Figure 3 shows the configuration of CRD7.

The CRD 7 is mainly composed of an outer tube 8, a cylinder tube 9, an index tube 10, and a piston tube 11.

CRD7 is disassembled by sequentially pulling out these tubes according to the following procedure.

By driving the roller chain 5, the movable cart 2 on which the CRD 7 is placed is moved to the side where the pull-out clamp unit 4 of FIG. 1 is disposed.

The index tube 10 containing the piston tube 11 of the CRD 7 is exposed from the end of the outer tube 8, and the exposed end is gripped by the pull-out clamp 4.

Next, the moving cart 2 is moved to its original position. As a result, the index tube 10 containing the piston tube 11 is pulled out from the outer tube 8.

The pulled out index tube 10
is gripped by the grapple device of the present invention.

The operation of pulling out the piston tube 11 from the index tube 10 is also carried out by the same operation steps as described in .

Next, FIG. 4 shows details of the grapple device.

The grapple device 3 includes an elevating drive mechanism 12, an opening/closing drive mechanism 13, a set of grapple arms 14, a screw mechanism 17, and a ball screw 20.

When disassembling the CRD 16, since the CRD 16 is a long cylindrical part, a plurality of grapple devices 3 (grapple units) are arranged in the axial direction, and each grapple unit is disassembled according to the disassembly procedure for long cylindrical parts. The grapple unit at the position is independently CRD
16. At this time, CRD1
There are several types of long cylindrical parts 6 with different diameters, but this is a type of grapple arm 1.
4, it can be gripped in a concentric state. One set of grapple arms 14 can be synchronized by being driven by an opening/closing mechanism 13, such as an air cylinder, via a rack pin-on, and will always grip the CRD 16 at its center position. Further, during the step of the disassembly procedure, the long cylindrical part of the CRD 16 grasped by the grapple arm 14 needs to be stored in an upward direction for the sake of the next disassembly procedure. At this time, the grapple arm 14 gripping the long cylindrical part of the CRD 16 is moved by the lifting mechanism via the screw mechanism 17 and the ball screw 20.
Move upward while holding CRD16. At this time, one of the conditions for the upper limit position of CRD 16 is that it should always be located below the water surface because CRD 16 is a highly radioactive substance, and furthermore, since the long cylindrical parts of CRD 16 are precision machined parts, bending deformation and damage may occur. It is also an important condition to handle the product in a way that does not cause damage.
For this reason, in particular, the plurality of lifting drive mechanisms must be operated at synchronous speeds, and it is also necessary that the plurality of grapple units always move up and down while holding the CRD 16 in a horizontal state. As an example of satisfying these conditions, a synchronous motor is adopted as the lift drive mechanism 12, and a rise/fall drive mechanism composed of a ball screw 20 and a screw mechanism 17 is used.

By adopting the present invention, it is possible to easily remotely automate the gripping, releasing, and lifting/lowering operations of various tubes with different diameters that make up the CRD using a single grapple arm, which saves labor in CRD maintenance and inspection work.
This has the effect of shortening work time and reducing radiation exposure for workers.

[Brief explanation of drawings]

Figure 1 is a front view of the CRD disassembly and cleaning equipment, Figure 2 is a side view of Figure 1, Figure 3 is a structural diagram of the CRD,
FIG. 4 is an overall view of the grapple device. 1...Disassembly and cleaning tank, 2...Moving trolley, 3...Grappling device, 4...Pull-out clamp unit,
5...Roller chain, 6...Drive motor, 7...
...CRD, 8...After tube, 9...Cylinder tube, 10...Index tube,
11...Viston tube, 12...Elevating drive mechanism, 13...Opening/closing drive mechanism, 14...Grapple arm, 15...Water surface, 16...CRD, 17...
...Screw mechanism, 18...Stop piston, 19...
...Drive piston, 20...Ball screw.

Claims (1)

[Scope of Claims] 1. In a grapple device for a control rod drive mechanism disassembly and cleaning device in which a plurality of control rod drive mechanisms are arranged along the axial direction of the control rod drive mechanism to be processed and each part of the control rod drive mechanism is sequentially disassembled and cleaned. , each grapple device is equipped with a grapple arm that concentrically handles the elongated parts of the control rod drive mechanism having different diameters, and each of the grapple arms can be raised and lowered as an individual movement of each grapple device or as a whole movement. A grapple device for a control rod drive mechanism disassembly and cleaning device, characterized in that it is equipped with a lifting mechanism. 2. In the grapple device of the control rod drive mechanism disassembly and cleaning equipment, which is arranged in plural units along the axial direction of the control rod drive mechanism to be processed and sequentially disassembles and cleans the control rod drive mechanism parts by part, each grapple device is The grapple arm is provided with a grapple arm that handles elongated parts of the control rod drive mechanism having different diameters in concentric positions, and an elevating mechanism that can raise and lower the grapple arms with the grapple arms in the concentric position, and the grapple arm 1. A grapple device for a control rod drive mechanism disassembly and cleaning apparatus, characterized by having a mechanism that independently opens and closes at concentric positions so as to grasp each long component according to a disassembly procedure of the drive mechanism.