Device for reading serial numbers of fuel assemblies

FIELD: power industry.

SUBSTANCE: device contains the first housing with through holes for passage of fuel assemblies (FA), around which illuminators are equally installed. Mirrors receiving the optical radiation reflected from fragments of side FA surface and installed with various turning angles of images provide uniform transfer of reflected mirror images to the plane of openings. The second housing with openings, which is located at some distance from the first one, is provided with radiation protection. Inside housing there arranged are video cameras consisting of video matrixes and objectives, and mirror labyrinths formed with inlet mirrors and outlet mirrors. Inlet mirrors are oriented towards outlet openings, and outlet mirrors - towards the objectives. External image control and processing unit is taken to clean room and connected to video cameras through cable communication lines. Invention is aimed at increasing radiation protection of video cameras owing to their possibility of being compactly arranged in remote housing.

EFFECT: radiation protective material and mirror labyrinths in the second housing provide additional radiation protection of video cameras.

5 cl, 4 dwg

 

The invention relates to the identification of fuel assemblies (FA), preferably of spent fuel assemblies (SFA), extracted from a nuclear reactor or basin storage, and intended for subsequent storage and processing.

The problem of identifying elements of nuclear power, especially SFA, recently acquired current value. As a rule, SFAS extracted from a nuclear reactor, have traces of operational impacts on the markings that make them difficult to read and identify. Herself identification marking may be an alphanumeric set of characterizing the serial number, and be done in different ways in the production process of FA. Words cause or mechanical etching, or mechanical squeezing.

Known various devices for reading such identification markings. For example, a device representing a combination of optical and ultrasonic readers that enhance the recognition accuracy of an identification code (U.S. patent No. 5.089.213, IPC G21C 017/10, 1992).

As a reader used a video camera with lights that install with providing three different angles of incidence on the reading surface.

(Nuclear Technology, Vol.72, Marc 1986, pp.321-327 or WO 9802888, IPC G21C 19/02, 17/08, 1998).

The disadvantage is that it requires precise positioning of the read portion relative to the camera, which complicates the reading process.

As a prototype of the selected device implementing the method according to the patent of Russian Federation №2309470 from 23.04.2004, IPC G21C 17/08, contained in the description to the specified patent.

The device includes illuminators and cameras with lenses that are placed in the composite annular body, with 4 cameras and 8 systems of mirrors arranged in a circle relative to the Central zone, which passes through the fuel Assembly. The entity known technical solution is to simultaneously transfer a mirror image of all fragments of the read area of the side surface along the perimeter on the camcorder, however, at least two or three of them will take the image of the flats. It does not require preliminary manipulation of the rotation of the fuel Assembly with respect to the reader.

The disadvantage is the weak security cameras from radiation, resulting in the need for frequent replacement.

The goal is to create easy-to-operate device for reading the serial numbers of FA, which design provides improved radiation protection of its sensitive the units.

The solution of this problem is provided as follows.

In the device for reading the serial numbers of fuel assemblies caused flats cylindrical surface of the shank of the fuel Assembly containing lights evenly around the perimeter covering the side surface of the shank, and mirrors to produce mirror images of all the fragments of the illuminated side surface, and also camcorders to register the received image, according to the invention the lighting and mirrors placed in the first enclosure with a through hole for the passage through it of the fuel Assembly and is provided with at least two translucent Windows in its side wall, and the mirror is installed with slope angles, providing uniform optical scan image side cylindrical surface controlled area in the plane of the translucent sealed Windows, and all the cameras are housed in a second housing that is remote from the first housing at the maximum possible distance and provided with transparent Windows facing the Windows of the first housing, and each of the cameras is configured to accept her intended part of the expanded image.

The technical result consists in the possibility to have the Alenia cameras from radiation hazard zones and compact enough of their location relative to each other in the most secure place. Compact and remote placement of the cameras is provided by the transfer deployed in the plane of the circular image on the video posted on the one hand, unlike the prototype, where video cameras placed around the circumference.

In addition, in the second case the introduced radiation-protective material, and for each camera made mirror maze, the input mirror which is converted to a corresponding input window and the output to the camcorder lens.

This provides additional radiation protection cameras in if the room's dimensions do not allow for a sufficiently large distance of one body from another, providing reliable protection.

In addition, the lighters are made in the form of elongated fluorescent lamps installed in the contact socket with replacement.

Replacement of elongated lamps can be carried out, for example, through planting holes in the top cover, closed operable plugs.

In addition, the back side of the lamp with respect to the lighted object set longitudinal screens-reflectors.

Their necessity caused by targeted use only the luminous flux of lamps for lighting readable plot.

In addition, the front side lamps have color extra long window across which the Finance colors.

This allows lighting the side surface of the light fluxes with different wavelengths at different angles, then used for analysis of the obtained color images that can increase their awareness and to ensure the accuracy of recognition with fuzzy identified characters.

Figure 1 shows a General view of the inventive device with the fragment of the optical system of the image transfer, figure 2 - three-dimensional image of the first enclosure without the top cover and side walls, figure 3 - three-dimensional image of the second enclosure without radiation protection and external walls, figure 4 - part of the first housing with the lamp-lighters.

The device comprises a first housing 1 (Fig 1, 2) with a through hole 2 for the passage of fuel assemblies (not shown) and transparent Windows 3, 4. The circumference around the through hole 2 is uniformly set illuminators 5. Mirror 6 for receiving reflected from fragments of the side surface of the fuel assemblies that are installed with different rotation angles of the images, provide a uniform transfer of the reflected mirror image in the plane of the window 3, 4, namely four neighboring fragment surface area of the fuel Assembly in the plane of each window. Part of the mirror 6 is used to transfer reflected from mirrors radiation in the plane of the window 3, 4, if it is not possible directly the th image transfer one mirror.

The second housing 7 with translucent Windows 8 is made with radiation protection 9. For convenience, the second case is made with a number of Windows equal to the number of cameras, i.e. four. Inside the housing 7 is placed video cameras, consisting of videometric 10 and lens 11 and mirror mazes formed by an input mirror 13 and the output mirror 14. The external control unit 15 and the image processing made in a clean room and is connected to the camera cable communication lines 16. The mirror maze and the fixed camera with a maximum degree of compact arrangement on the plate 16 by means of brackets 17 and 18, respectively (figure 3). The input mirror 13 is focused on the entrance window 8, the output mirror 14 in the lens 11.

Illuminators 5 made in the form of elongated fluorescent lamps, rear side equipped with screens-reflectors 19 (figure 4) and installed in the contact socket 20, 21. The upper contact of the socket are closed by removable plugs 22. Color box 23 defined by the illuminated object. Between the lamps 5 available space is blocked by the glass 24 to output reflected from the read surface of the optical radiation on the mirror 16.

The operation of the device is as follows.

Previously in the hole 2 of the housing 1 is inserted FA with shank, PA cylindrical side surface to the th performed the flats with the serial number. The need for the positioning of the fuel Assembly is missing.

Then simultaneously switched on the lights 5 and the mirror 6 are transferred image increments in azimuth of 45 degrees in the plane of the translucent Windows 3, 4. Redundancy mirror 6 is caused by the inability of the direct projection mirror image in the plane of the window 3, 4 from some sections read surface without the use of additional mirrors. Next, a detailed picture of the entire readable area of the lateral cylindrical surface through Windows 8 and mirror mazes 12 remote housing 7 is supplied to the video camera 10, 11. In a particular embodiment, for each frame of each camera is moved two images adjacent fragments of the illuminated surface. Therefore, four cameras simultaneously record the image of the entire reading surface. At least two video cameras, recording the adjacent parts of the surface, capture the image of the flats. However, the number of cameras and, accordingly, the optical systems of the image transfer may be different. The possibility of unilateral reception of optical radiation by all cameras made it possible to combine them into a single body, placing it in the most remote from the source of radioactivity. Additional protection is provided by radiation for any material 9 and the mirror maze 12.

When using colored boxes 23 each of these images is recorded together neighboring colors of the lights. Although this image of the same surface area FA, however, they differ from each other due to different angles of incidence of the radiation on the surface of the fuel assemblies. As a result, the combination of the obtained image becomes more informative. In this case, the redundancy information is used to improve the reliability of recognition of implicit symbols in the course of the subsequent image processing unit 15 by dividing the obtained color images by color illuminators, i.e. in the direction of incidence of the optical radiation in the registered area.

Thus, the proposed device allows Multiview imaging of non-SFA with remote and contactless reading rooms, ensuring maximum radiation protection for vulnerable hosts.

1. A device for reading the serial numbers of fuel assemblies caused flats cylindrical surface of the shank of the fuel Assembly containing lights evenly around the perimeter covering the side surface of the shank, and mirrors to produce mirror images of all the fragments of the illuminated side surface, and also camcorders to register the tion of the received image, characterized in that the lights and mirrors placed in the first enclosure with a through hole for the passage through it of the fuel Assembly and is provided with at least two translucent Windows in its side wall, and the mirror is installed with slope angles, providing uniform optical scan image of the lateral cylindrical surface of the controlled area in the plane of the translucent sealed boxes, and video camera are housed in a second housing that is remote from the first housing at the maximum possible distance and provided with transparent Windows facing the translucent Windows of the first housing, each of the cameras is configured to receive the corresponding part of the expanded image.

2. The device according to claim 1, characterized in that in the second case the introduced radiation-protective material and for each camera made mirror maze, the input mirror which is converted to a corresponding input window and the output to the camcorder lens.

3. The device according to claim 1, characterized in that the luminaire is made in the form of elongated fluorescent lamps installed in the contact socket with replacement.

4. The device according to claim 3, characterized in that the back side of the lamp with respect to the lighted object installations which are longitudinal screens-reflectors.

5. The device according to claim 3, characterized in that the front side lamps have color extra long window with alternating colors.



 

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