JPH02163689A - Radioactive surface contamination inspecting apparatus - Google Patents

Abstract

PURPOSE:To make wiping and measuring in parallel and to allow inspection in a short period of time by cutting a filter paper tape with a cutter to form a filter paper card, then making measurement. CONSTITUTION:The filter paper tape 43 let off from a reel 44 is fed in order of a rubber roller 50, press rollers 52, and a cutter 53 by feeders 45, 46. The tape 43 is pressed by the roller 50 to an object 23 to be inspected to wipe the surface of the object 23 during the course of this feeding; thereafter, a sealing tape 51 is stuck to the surface of the tape 43 subjected to the wiping of the object 23 by the rollers 52 to preserve the sample and to prevent the diffusion of a contaminating material. This tape is cut to a required length by the cutter 53 and is thereby made into the filter paper card 54. The card 54 formed in such a manner is sent to a measuring instrument 58 in a measuring device 61 provided separately from the wiping device 35 and is subjected to measuring the surface contamination density of the object 23.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an apparatus for inspecting radioactive surface contamination by taking a sample from the outer surface of an object to be inspected.

[Prior Art] In general, most of the radioactive waste generated at nuclear power generation facilities, etc. is reduced in volume by appropriate means suitable for the nature of the waste, such as incineration, and then packed in drums as a solidified material. It is stored as radioactive miscellaneous solid waste in storage warehouses within nuclear power generation facilities.

When carrying out this storage, it is necessary to measure the surface contamination density in order to transport and manage the radioactive miscellaneous solid waste.
) Holding filter paper a in your hand, rub filter paper a strongly against the surface of the object to be measured, wipe off the radioactive contaminants adhering to the surface of the object to be measured, and smear) the radioactive contaminants adhering to filter paper a The amount of radioactive contaminants was measured using a measuring device (usually a GM tube or the like), and the density of surface contamination was measured.

Note that this measurement is performed at a plurality of locations on one object to be measured.

In such work, it takes time and effort to wipe down the objects to be measured, such as dozens to hundreds of drums, and moreover, workers are forced to work close to radioactive miscellaneous solid waste. Even if the radiation level of individual radioactive miscellaneous solid waste is low, the cumulative radiation exposure may not be negligible during long hours of work, so from the perspective of shortening work time and reducing radiation exposure, It is desirable to make measurements remote or automated.

In response to such demands, a radioactive surface contamination inspection device as shown in Japanese Patent Application No. 59-235391 (Japanese Unexamined Patent Publication No. 81-I 12984) was recently developed using figures 7 to 9 (mount a). I will briefly explain.

An object to be inspected, such as a drum 1 filled with radioactive waste whose volume has been reduced by incineration, etc., is placed on a turntable 27, and a support plate 3 is provided near the drum 1, and a bearing 4 is attached to the support plate 3. A rotating arm 6 is supported via a rotating shaft 5, and a swinging arm 7 is held at the tip of the rotating arm 6 so as to be able to swing up and down.

A tape-shaped filter paper 11 made by adhering a long P paper 10 to the surface of a long core material 9 with an auxiliary material 8 adhered to the back side as shown in FIG. 9(a) ([)) is fed out. A photoelectric switch 13 in which an edge reel 12 is attached to the rotary arm 6 and a tape-shaped filter paper 11 fed out from the feed reel 12 is provided in the swing arm 7;) a cylinder device 14 for fixing the filter paper;
, pressing IJ roller 5, thin film roll tape 16 (in tape form)) After turning the hook so as to pass through the bonding roller 7 etc. that is attached to the surface of the filter paper 11, the photoelectric switch 18 provided on the rotary arm 6, the measuring device 19, and the tape ) The filter paper 11 is passed through a foot roller 20 or the like that drives the feeding thereof, and then wound up with a take-up reel 21.

Note that 22 is marks attached to the tape-like paper 11 at regular intervals.

The radioactive surface contamination inspection device described above uses a feed roller 20 to feed a tape-shaped filter paper 11 by friction drive from a payout reel 12 toward a take-up reel 21, and marks 22 attached to the tape-shaped paper 11 being fed. When this is detected by the photoelectric switch 13 of the swing arm 7, the photoelectric switch I3 sends a signal to stop the driving of the foot roller 20, and also extends the cylinder device 14 to remove the tape-shaped filter paper 11.
The position of is fixed, and in this state, the swinging arm 7 is swung downward to press the roller 5 against the surface of the drum 1.
After that, by driving the turntable 2 and giving rotation to the drum 1, the filter paper 11 (in the form of a tape on the surface of the roller 15) wipes the surface of the drum 1, and after wiping is completed, the swinging arm 7 is moved upward. The tape-shaped filter paper 11 is separated from the drum 1 by swinging, the tape-shaped filter paper 11 is released from the fixation of the tape-shaped filter paper 11 by the cylinder device 14, and the tape-shaped filter paper 11 is fed by the feed roller 20 in the same manner as described above. When the filter paper 11 passes through the bonding roller 7, a thin film roll tape 16 is pressed onto the surface of the filter paper 11 to preserve the wiped portion of the filter paper 11 as a sample and prevent the spread of contaminants. When the photoelectric switch 18 provided on the rotary arm 6 detects that the filter paper 11 has reached the measuring device 19 by the corresponding mark 22 on the filter paper 11, the photoelectric switch 18 detects that the filter paper 11 has reached the measuring device 19. In response to the signal, the feeding of the tape-like paper II is stopped and a measuring device 19 is activated to measure the surface contamination density of the drum can 1 eJ.

Incidentally, by rotating the rotary arm 6, it is possible to similarly inspect the side surface, bottom surface, etc. of the drum can 1.

[Problems to be Solved by the Invention] However, the radioactive surface contamination inspection device described above has the following problems.

■ The filter paper 11 is wound up by the take-up reel 2I (in the form of a tape sent out from the feeding reel 12), and the pressure roller 15 and measuring device 19 are placed in the middle of the path, so the paper is in the form of a tape) The path of the filter paper 11 becomes longer, and the tension applied to the tape-like paper 11 increases accordingly, making it easier to cut the tape-like paper 11, and the structure becomes complicated, resulting in the formation of small nails.

■ It is preferable because it is attached to the heavy measuring instrument 19 or the rotary arm 6 and has a 6J movement.

■ A roller 15 presses the tape-shaped filter paper 11 in the middle of its path.
Since a measuring device 19 is installed to perform both wiping and measurement, situations such as not being able to measure until the wiping is finished or only wiping can be done until a total of 7111 is completed may occur, resulting in a reduction in efficiency. It took a long time to inspect (7 minutes).

■ Since the filter paper 11 (tape-like) is rolled up,
When pressing the leading and trailing ends of the tape-shaped paper 11, a long portion corresponding to the path from the roller 15 to the take-up reel 21 cannot be used for measurement, resulting in poor yield.

■ Since the filter paper 11 (tape-shaped) is fed by friction drive by the feed roller 20, it tends to slip and not be fed accurately.
It is necessary to attach a mark 22 for detecting the position of 1 and to provide a photoelectric switch 13 or the like so that the mark 22 can be detected.

■ Tape-like) filter paper] Wiping the drum j using step 1 is as follows:
Since the swinging arm 7 is oscillated to press the roller 5 against the drum 1 with a constant force, it is difficult to adjust the pressing force.

The present invention aims to solve the above-mentioned problems.

[Means for Solving the Problems] The present invention comprises:) a reel for feeding out a filter paper tape; a feeding device for feeding the filter paper tape from the reel; and a rubber roller for pressing the filter paper tape from the feeding device) against an object to be inspected. , a pressure roller that applies a sealing tape to the surface of the door paper tape (which was pressed against the surface of the object to be inspected and wiped with the rubber roller), and a filter paper tape of the required length to which the sealing tape was applied. a wiping device equipped with a cutter for cutting into cards; and a wiping device provided separately from the wiping device;
The present invention relates to a radioactive surface contamination inspection device comprising: a measuring device equipped with a measuring device for measuring the radioactive surface contamination density of a filter paper card.

[Operation] In the wiping device, the P paper tape that is unwound from the reel is
The feeding device sends the filter paper tape to the rubber roller, pressure roller, and cutter in this order. On the way, the filter paper tape is pressed against the object to be inspected by the rubber roller and wipes the surface of the object to be inspected. After that, the paper tape is sent to the object by the pressure roller. A sealing tape is applied to the wiped surface of the test object to preserve the sample and prevent the spread of contaminants, and the sample is cut into a required length with a cutter to form a filter paper card.

The filter paper card (formed in this way) is sent to a measuring device in a measuring device provided separately from the wiping device, and the surface contamination density of the object to be inspected is measured.

Furthermore, by providing a feed hole in the filter paper tape and using a sprocket as the feed device, the filter paper tape can be accurately fed without slipping, and the amount of feed can be detected by counting the feed holes.

Furthermore, by making the rubber roller softer toward the outer periphery, the force with which the filter paper tape is pressed against the object to be inspected can be easily adjusted.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 show an embodiment of the present invention.

FIG. 1 is a schematic overall perspective view showing a configuration example of the present invention,
It can be stored protruding from between the rollers of the roller conveyor 24 at an appropriate position on the roller conveyor 24 that conveys the object to be inspected 23 (hereinafter referred to as the drum 23) such as a drum filled with radioactive waste whose volume has been reduced by incineration or the like. A three-point support type turntable 25 is provided, and a surface dose rate detector 27, a label device 28, etc. are supported toward the drum can 23 on a support 2G erected near the installation position of the turntable 25 of the roller conveyor 24. A screw 31 that extends vertically and is driven by a motor 30 is provided on another column 29, and a support device 32 is supported on the screw 31 so as to be able to move up and down. A frame 33 is supported so as to be pivotable in the periphery, and a wiping device 35, which forms part of the invention, is supported so as to be pivotable horizontally by means of another motor 34 of the frame 33.

In addition, 36 is a 1m dose rate detector installed at a position 1 mm away from the drum can 23, 37 is a photoelectric switch for decelerating and stopping the drum can 23, 38 is a stopper for positioning the drum can 23, and 39 is a label attached to the drum can 23. shows.

The wiping device 35 is constructed by disposing a piece of filter paper 42 on the surface of a tensile strength backup tape 41 with equally spaced spout holes 40 formed on both left and right sides as shown in FIG. a reel 44 that feeds out a filter paper tape 43 (made of glued to the reel 44; , core t44 as shown in FIG.
A rubber roller 50 for pressing the outer periphery of 7 is covered with soft rubber 48, sponge rubber 49, etc. in multiple layers in order so that it becomes softer toward the surface, and a sealing tape 51 made of a thin film such as polyethylene) is used for filter paper tape 43. A pressure roller 52 that presses and seals the surface, and a sprocket-type feed device 4
6,) a cutter 53 that cuts the filter paper tape 43 into a card shape of a predetermined length, and a transport device 55 that transports the filter paper card 54 (formed by cutting by the cutter 53).
The paper tapes 43 are arranged in order from the upstream side in the feeding direction.

In addition, 56 is a guide roller, 57 is a reel for the sealing tape 51, and sprockets 45 and 40 are two paper tapes 4.
The rotating speeds of the tapes 3 are synchronized so that they do not shift during wiping, and tension can be applied by built-in torsion springs (not shown). A counter (not shown) for counting is attached.

A measuring device 58, and a filter paper storage box 59 (for disposal), which can be connected at a predetermined position to the conveying device 55 for the filter paper card 54 (of the wiping device 35), and between the measurement device 58 and the filter paper storage box 59 (for disposal). A straddling conveyance device 60 is provided to form a measurement device 61 separate from the wiping device 35 above the ground.

Next, the operation will be explained.

First, the tip of the filter paper tape 43 (on the reel 44) is set in the wiping device 35 so as to be guided to the cutter 53 through the guide roller 5B, sprocket 45, rubber roller 50, pressure roller 52, and sprocket 46 in this order.

After setting the filter paper tape 43, set the sprocket 45.
A required tension is applied to the part of the filter paper tape 43 between the sprockets 45 and 46 by a built-in torsion spring to take up the slack of the filter paper tape 43, and the two paper tapes 43 are pressed against the rubber roller 50, and the motor 30
The support device 32 is appropriately moved by driving the wiping device 35 as appropriate to press the rubber roller 50 of the wiping device 35 against the object 23 to be inspected, such as a drum. At this time, the rubber roller 50 is multilayered by attaching soft rubber 48, sponge rubber 49, etc. to the outer periphery of the core material 47, so that the center is hard and the outer periphery is soft. When pressed against the drum can 23, the surface of the rubber roller 50 is deformed to ensure that the length of the contact portion of the paper tape 43 with the drum can 23 is the required length, and to even out the wiping force applied to the contact portion. Because you can
Drum 2 of filter paper tape 43 (which is considered to be very difficult)
Securing a contact portion of the required length and adjusting the wiping force for No. 3 are greatly simplified.

) After pressing the filter paper tape 43 against the drum can 23, the tongue table 25 is driven to rotate the drum can 23 and wiping with the filter paper tape 43 is performed.

When wiping is completed, the support device 32 is moved in the same manner as described above, and the rubber roller 50 of the wiping device 35 is moved to the drum can 23.
Separate it from the surface,) feed the filter paper tape 43 by the required amount (by the synchronous rotation of sprockets 1-45, 46 that engage with the feed hole 40 of the filter paper tape 43), and wipe the surface of the part of the paper tape 43 with the pressure roller 52. Seal tape 51
affixed to protect the sample and prevent the spread of contaminants.

From then on, by) repeating step 1 one after another while feeding the filter paper tape 43 intermittently,) wiping another part of the filter paper tape 43 on another drum can 23 or another part of the drum can 23, and 2) wiping off the paper tape 43. The completed part will be sealed.

In this way, as the wiping and sealing work progresses, the filter paper tape 43 (of the part that was wiped first) is removed from the cutter 53.
, the filter paper card 54 is cut by using a cutter 53. Therefore, as the wiping operation progresses, the subsequent wiping portion becomes the p-paper card 54.

At this time, since the filter paper tape 43 is cut by the cutter 53, it cannot be used for wiping) from the cutter 53 at the front and rear ends of the filter paper tape 43 to the rubber roller 5
The length of the paper tape 43 can be shortened, and therefore) the number of times the filter paper tape 43 can be wiped is increased, the filter paper tape 43 is effectively utilized, and the number of times the door paper tape 43 is replaced is reduced.

Incidentally, the portions of the front and rear ends of the paper tape 43 that cannot be used for wiping are also cut into cards by the cutter 53.

In addition, since the filter paper tape 43 is provided with a feed hole 40 and is fed by subblocks 1-45 and 46, the filter paper tape 43 is fed reliably without slipping, and the feeding is accurate. By counting the holes 40), the feed amount of the filter paper tape 43 can be detected without having to specially mark the filter paper tape 43 and detect the mark with a sensor or the like, thereby simplifying the configuration.

Furthermore, since the filter paper tape 43 is cut by the cutter 53, the path of the filter paper tape 43 is shortened.
Unreasonable tension is prevented from being applied to the filter paper tape 43, and the structure is simple and lightweight.

The filter paper card 54 (formed by cutting) is transferred to the conveying device 5
5, it is sent to the transport device 60 on the measuring device 61 side. When the conveyance device 60 on the measuring device 61 side receives the filter paper cards 54, the first and last several unwiped P paper cards 54 are directly discarded) and sent to the filter paper storage box 59 for disposal.
After the subsequent wiping, the filter paper card 54 is sent to a measuring device 58 to measure the surface contamination density, and is then sent to a filter paper storage box 59 for disposal.

At this time, since the measuring device 61 is provided separately from the wiping device 35, even if the wiping device 35 is performing the wiping operation, measurement can be performed in parallel. Both measurement tasks can be handled efficiently.

Further, since the measuring device 61 is provided separately from the wiping device, the measuring device 58 can be fixed.

FIG. 5 shows another embodiment of the present invention, in which the conveying device 5 on the wiping device 35 side has substantially the same configuration as FIGS. 1 to 4.
A box 63 that can store several filter paper cards 54 is removably attached downstream of the box 63.
When a certain amount of filter paper cards 54 are accumulated in box 6,
3) Transfer the filter paper card 54 to the transport device 6 of the ΔPI device 61.
This allows measurements to be made in batches at zero, and the same effects as in the embodiment described above can be obtained.

It should be noted that the radioactive surface contamination inspection device of the present invention is not limited to the above-described embodiments, and it goes without saying that various changes can be made without departing from the gist of the present invention.

[Effects of the Invention] As explained above, according to the radioactive surface contamination inspection device of the present invention, various excellent effects as described below can be achieved.

(2) Since measurements are made after cutting the P-paper tape with a cutter to form two paper cards, wiping and measurement can be performed in parallel, and therefore inspection can be carried out in a short time.

■) Since the filter paper tape is cut with a cutter,) the path of the filter paper tape is shortened,) the area that can be used for measuring the filter paper tape is increased, and the yield can be improved; Replacement frequency can be reduced.

(2) Since the filter paper tape is cut with a cutter, the path of the filter paper tape is shortened, and (1) it is possible to prevent excessive tension from being applied to the paper tape.

■ Since the wiping device and measuring device are separate, the measuring device can be fixed.

■ Feed holes are provided in two paper tapes and the sprocket is used to feed them, making the feed more accurate.) The feed amount of one paper tape can be detected by the number of feed holes, which simplifies the configuration. I can do something.

- Since the rubber roller is made to become softer toward the outer periphery, it is possible to easily adjust the force with which the paper tape is pressed against the object to be inspected.

[Brief explanation of the drawing]

Fig. 1 is a schematic overall perspective view of an embodiment of the present invention, Fig. 2 is a schematic side view of an embodiment of the invention, Fig. 3 is a side sectional view of the rubber roller of Fig. 2, and Fig. 4 is). 5 is a schematic side view of another embodiment of the present invention, FIG. 6 is an explanatory diagram of a manual inspection method, FIG. 7 is an overall side view of a conventional device, and FIG. 8 is a perspective view of a paper tape. is a partially enlarged view of Figure 7, Figure 9 (Tayama)
7 is an explanatory diagram of the tape-shaped door paper used in FIG. 7. In the figure, 23 is the object to be inspected (drum), 35 is a wiping device, 43 is a paper tape, 44 is a reel, 45.46 is a feeding device (sprocket l-), 50 is a rubber roller, 51 is a sealing tape, 52 is a Pressure roller, 53, cutter, 54
58 is a measuring device, and 61 is a measuring device.

Claims (1)

[Claims] 1) A reel for feeding out a filter paper tape, a feeding device for feeding the filter paper tape from the reel, a rubber roller for pressing the filter paper tape from the feeding device against an object to be inspected, and a device to be inspected with the rubber roller. A wiping device equipped with a pressure roller that applies a sealing tape to the surface of the filter paper tape that has been pressed against the surface of an object and that has been wiped, and a cutter that cuts the filter paper tape with the sealing tape pasted into filter paper cards of a required length. A radioactive surface contamination inspection device comprising a wiping device and a measuring device provided separately from the wiping device and equipped with a measuring device for measuring the radioactive surface contamination density of a filter paper card. 2) The radioactive surface contamination inspection device according to claim 1, wherein the filter paper tape is provided with a feed hole, and the feed device is a sprocket that meshes with the feed hole of the filter paper tape. 3) The radioactive surface contamination inspection device according to claim 1, wherein the rubber roller is formed so that it becomes softer toward the outer periphery.