JPH0377472B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a remote smear device that remotely inspects the surface of an object for the presence of contaminants.

Generally, when drums containing radioactive waste generated from nuclear facilities are transported out of the storage facility, the surface is inspected for contamination or not, and if there is contamination, it is removed and the absence of contamination is confirmed. It is necessary to attach a label showing the required data about the item. In such work, it is desirable to avoid the risk of radiation exposure as much as possible, and avoidance of exposure is especially essential when handling medium to high level radioactive materials.

Conventionally, a method known as a smear test has been used to inspect the surface of drums for radioactive contamination.This test involves placing the drum on a turntable that rotates and moves up and down, and applying a smear test to the top and sides of the drum. After a wiping paper called paper is brought into contact with the drum, it is collected and inspected for the presence of contaminants and the degree of contamination.Based on the results, the contamination state of the drum is determined. A method of performing these operations by remote control has also been proposed.

However, in the past, it was not possible to perform the above-mentioned smear test on the bottom surface of the drum, so the determination of the presence or absence of contamination was based on the inspection results of the top and side surfaces. Therefore, if only the bottom surface was contaminated, this There is a risk that it will be determined that there is no contamination. Furthermore, since the pressing force of the smear paper cannot be detected, there is a risk that the smear paper may be damaged due to excessive pressing, or that contaminant adhesion may be incomplete due to insufficient pressing, leading to misunderstandings. Furthermore, the decontamination work and labeling work performed based on the results of the above smear test conventionally required manual work by workers wearing protective clothing or the use of separate equipment, which led to concerns about safety, workability, and There is a problem with equipment costs.

This invention can eliminate the drawbacks of the conventional smear test for inspecting the presence or absence of radioactive substance contamination on the surface of drums as described above, and can also solve the same problems with other contaminants such as toxic substances and harmful microorganisms, as well as other objects other than drums. This provides a remote smear device that can also be used for testing. That is, the apparatus of the present invention is equipped with a means for rotating an object to be inspected, and a robot whose tip can be replaced with a jig for holding smear paper through a jig head, and these are installed in a space on the operation room side. On the other hand, in a remote smear device placed in a space separated by a protective wall, the means for rotating the object to be inspected is a ring-shaped elevating table, and on the elevating table, multiple points around the bottom of the object to be inspected are moved by motorized driving wheels, guide rollers, etc. The jig head is attached to the tip of the robot so that it can be rotated up and down at an angle of 90 degrees each around the mounting base to the robot.
In addition, the tip side is configured to be able to slide forward and backward with respect to the mounting base on the robot, and a pressure detection mechanism that detects the pressing force of the jig as a retraction displacement against a spring on the tip side using a differential displacement device, etc. It is characterized by having a built-in.

An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, 1 is a drum containing radioactive waste, 2 is a holding device on which the drum 1 is placed and rotated and raised and lowered, 3 is a 3-axis robot, and 4 is an operation panel 5. 8 is a monitoring window provided in the protective wall 4, and 9 is a communication port provided in the protective wall 4 for collecting smear paper and exchanging jigs. , 10 is the shielding door.

The holding device 2 has three ball screws 13 erected at equal intervals on a base 11 and connected to a horseshoe-shaped guide frame plate 12 at the top, and the ball screws 13 are connected to a driving device 14. An annular elevating table 15 that is elevated and lowered by... is installed.
Further, each motor 1 is mounted on the lifting table 15.
Horizontal shaft-type drum rotation driving wheel 17 driven by 6
Three supporting devices 19, each having a guide roller 18 in the form of a vertical shaft, are arranged at equal intervals, and furthermore, three supports 21 each have a guide roller 20 pivotally attached to the tip thereof.
...are arranged at equal intervals. and drum 1
is placed on the driving wheel 17 with the peripheral part of its lower surface in contact with the driving wheel 17, and is rotated by the drive of the driving wheel 17, and its position is regulated by the guide roller 18 that contacts the lower side of the driving wheel 17, so that the center of rotation is This is done so that no misalignment occurs.

The three-axis robot 3 includes a turntable 23 on a base 22 that rotates within an angle range of 120 degrees in a horizontal plane, and a cart 25 that moves up and down along guide columns 24, 24 erected on the turntable 23. It is provided. Reference numeral 26 denotes a drive device that rotates a ball screw 27 to move the cart 25 up and down. The trolley 25 is equipped with a jig head traversing device 29 having a jig head 28 pivotally attached to its tip, and this traversing device 29 is driven by a ball screw 30b which is rotationally driven by a motor 30a as shown in FIG. It is composed of an electric cylinder 30 that moves two bars 30c, 30c, each having a jig indexing device 31 fixed to its tip. Furthermore, the jig indexing device 31 has a function of swinging the jig head 28 at an angle of 90° in each direction up and down.

FIG. 4 shows the internal structure of the jig head 28. The jig head 28 includes a base portion 32a, a cylindrical portion 32b, and an annular connector 32 that are connected to the jig index device 31.
A chuck mechanism part 35 which is slidable in the axial direction via a stroke bearing 33 and is attached to the base part 32a via a coil spring 34 is housed in a case 32 consisting of a rear end of the chuck mechanism part 35. The differential transformer 37 generates a potential change depending on the position of the iron piece 36 coupled to the differential transformer 37. The chuck mechanism section 35 is open at the front end side and has a compressed air inlet 38a for removing and removing jigs and a compressed air inlet 38b for rotating the decontamination brush and attaching labels to a part of the side surface.
In a base body 35a having a substantially cylindrical configuration, an inner and outer cylinder 35b, both of which are attached to the base body 35a by coil springs 39a and 39b and are slidable in the axial direction, are provided.
35c, and the smear jig 40 is attached by fitting the locking sphere 41 to the attachment part 40a of the smear jig 40 fitted into the tip of the outer cylinder 35c, and compressed air is introduced. The structure is such that the smear jig 40 is removed by introducing compressed air from the port 38a. A smear paper 42 is held in the smear jig 40 with its peripheral end clamped between a main body 40b and a fastener 40c screwed onto the main body 40b.

To conduct a smear test using the remote smear device configured as described above, first, the drum 1 to be tested is carried into the smear work chamber 7 using an overhead traveling crane (not shown), and is suspended from the holding device. The lifting table 15 of No. 2 is raised and the drum 1 is placed on the driving wheels 17 so as to be received from below. In the smear test on the bottom surface of drum can 1,
As shown in FIG. 5A, the drum can 1 is rotated with the lifting table 15 positioned above, and the jig head 28 is advanced below the drum can 1 by the traversing device 29, and then the jig head 28 is The smear jig 40 is displaced upward by the tool indexing device 31 and pressed against the center of the lower surface of the drum 1 with an appropriate pressure. Next, in this pressed state, the entire lower surface of the drum 1 is wiped with the smear paper 42 by moving the jig head 28 in the direction of the arrow shown at an appropriate speed according to the rotation of the drum 1. The smear test on the upper surface of the drum 1 can be carried out by rotating the drum 1 with the lift table 15 positioned at the lower position, positioning the traversing device 29 at the upper position, and moving the jig head 28 onto the drum 1 as shown in FIG. 5B. placed above,
Next, the jig head 28 is moved downward to press the smear jig 40 against the center of the upper surface of the drum 1, and then the jig head 28 is moved in the direction of the arrow shown in the figure. Furthermore, the smear test on the side surface of the drum 1 is performed by rotating the drum 1 with the lifting table 15 in the middle position as shown in FIG. The device 29 may be lowered or raised.

In these operations, the pressing force of the smear paper 42 is generated by the chuck mechanism 35 of the jig head 28 retreating against the spring 34 in response to the pressing force when the smear jig 40 is pressed against the drum can 1. It is sensed via the differential transformer 37. Therefore, if the position of the jig head 28 is adjusted in conjunction with the traversing device 29 based on the detected value, the pressing force of the smear paper 42 can be corrected to an optimal value.

After the necessary contact with the smear paper 42 is completed, the smear jig 40 is separated from the drum can 1 by the traversing device 29, and the smear jig 40 is moved by rotating the turntable 23 and rotating the entire upper part by 120 degrees. Open the shielding door 10 towards the protective wall 4 side and access the communication port 9.
The smear jig 40 is inserted into the operation chamber 6, and the smear jig 40 is grabbed by a jig chuck device 43 provided inside the smear jig 40.
Take it out to the side and measure the radioactivity of the smear paper to determine whether it is contaminated. Note that this determination is not necessarily performed after the smear paper 42 is brought into contact with the entire surface of the drum 1, but may be performed every time a preset partial surface is contacted in order to reduce the decontamination work described later. .

If contamination is found in the smear test, a decontamination brush that has the same mounting shape as the smear jig 40 and rotates with the air pressure introduced from the compressed air inlet 38b of the jig head 28 A jig (not shown) is attached to the jig head 28 instead of the smear jig 40, and the surface of the drum 1 is decontaminated in the same manner as in the smear test. During this decontamination, various chemicals may be used or water may be poured as necessary. Also, the effectiveness of decontamination can be confirmed by another smear test.

Furthermore, for drums 1 for which no contamination was found in the initial and post-decontamination smear tests, a label indicating that they are non-contaminated and necessary data such as radioactivity measurements is affixed to the surface. As shown in FIG. 6, this operation is carried out using a smear jig 40 that is equipped with a mounting part 44a having the same shape as the smear jig 40, has a label holding recess 44b in the end face, and further extends from the recess 44b to the mounting end face. A label pasting jig 44 with an air hole 44c is attached to the jig head 28, and a label (not shown) with an adhesive or adhesive layer is applied to the recess 44b to open the compressed air inlet 38b. The label is suctioned and held through the jig 4 as described above.
4 is brought into contact with a predetermined portion of the surface of the drum 1, and then compressed air is sent through the compressed air inlet 38b and the label is affixed using the air pressure.

The drum 1 with the label pasted thereon may be lifted by an overhead traveling crane and carried out of the smear work room 7. Incidentally, all of the above operations are performed by remote control from the operation room 6.

In the above example, the smear test and decontamination labeling work of drums containing low-level or medium-high level radioactive waste were explained.
The device of the present invention can be similarly applied to surface contamination inspection and decontamination of containers or objects other than drums, and can be similarly applied to cases where the contaminants are toxic substances other than radioactive substances, harmful microorganisms, etc. Furthermore, although the above description has been made as equipment installed in a building, it is also possible to combine the components of this invention, including the protective wall, into a mobile unit that can be moved or transported, and all operations can be performed using a predetermined program. It is also easy to configure the system so that it can be performed automatically according to the following.

As described above, according to the remote smear device according to the present invention, it is of course possible to inspect the top and side surfaces of the object to be inspected, and in particular, it is also possible to inspect the bottom surface of the object to be inspected. That is, in order to inspect the lower surface, the lift table is raised, a ring-shaped jig can be inserted from the lower surface, and rotational support means are supported at multiple locations around the bottom of the object to be inspected.
Furthermore, this is because the jig head can be erected upward at an angle of 90 degrees.

Furthermore, since the jig head is equipped with a pressure detection mechanism, it is possible to maintain the pressing force at an appropriate value and avoid damage to the smear paper and a decrease in reliability due to insufficient pressing.

[Brief explanation of drawings]

FIG. 1 is a plan view showing an example of a remote smear device according to an embodiment of the present invention, and FIG. 2 is a side view thereof.
Figure 3 is a longitudinal sectional view showing the internal structure of the traverse device, Figure 4 is a sectional view of the jig head equipped with a smear jig, Figures 5 A, B, and C are schematic diagrams showing the smear test operation. FIG. 6 is a sectional view of a jig head equipped with a label sticking jig. 1... Drum (object), 2... Holding device, 3... 3
Axial robot, 4...protective wall, 6...operation room, 7...smear work room, 22...base, 23...turntable,
25...Dolly, 28...Jig head, 29...Traversing device, 37...Differential transformer (pressure detection mechanism), 40...
Smear jig, 44... jig for label pasting.

Claims (1)

[Claims] 1 Equipped with means for rotating the inspection object and a robot whose tip can be replaced with a jig for holding smear paper through a jig head, and these are separated from the operation room side by a protective wall. In a remote smear device placed in space, the means for rotating the inspection object is
It consists of an annular elevating table and a support device that rotatably supports multiple locations around the bottom of the object to be inspected on the elevating table via motorized driving wheels, guide rollers, etc., and the jig head is attached to the robot. The jig is attached to the tip of the robot so that it can be rotated up and down at an angle of 90 degrees around the mounting base, and the tip side is configured to be able to slide forward and backward with respect to the mounting base on the robot. A remote smear device is characterized in that it has a built-in pressure detection mechanism that detects the pressing force of the smear as a retraction displacement against a spring on the tip side using a differential displacement device or the like.