A radiation dose detector screening system and screening method

Abstract

The present invention discloses a radiation dose detector screening system and screening method, the screening system includes a radiation source, a material tray, a base and a base; the radiation source is provided with a laser ranging module; the material tray is a three-layer stacked structure, consisting of two outer baffles and a limit baffle sandwiched therebetween, the limit baffles include three types; the material tray is fixed on a height-adjustable base through a base; the base includes a first base and a second base, both of which include a bottom plate and a vertical plate, and the two vertical plates clamp the bottom of the material tray to keep the material tray upright; the base includes a movable base plate, a positioning hole for placing a positioning scale is formed in the center of the movable base plate, and multiple angle identification lines are radiated from the center of the positioning hole to the surrounding areas. The present invention realizes the screening of multiple different types of radiation dose detectors through a brand-new structural design, accurate positioning, and convenient use.

Description

Technical Field

[0001] The invention relates to the field of radiation dose measurement, in particular to a radiation dose detector screening system and screening method. Background Art

[0002] In order to ensure the consistency of the radiation dose detector's response results to radiation, before the detector is installed on the dosimeter or dose test, it needs to go through a very important procedure, which is screening. The currently commonly used method of ensuring the consistency of radiation dose detectors is to place a certain number of detectors (disc-shaped, glass tube-shaped or square-shaped, etc.) from the same batch in a closed container, place them side by side and fix them, and then place them as a whole at a certain distance from the radiation source for radiation irradiation. Then, they are measured on the same measuring instrument, and the detectors with basically consistent measurement data are retained. In the process of irradiation by the radiation source, it is necessary to ensure that the dose detectors are evenly distributed in the radiation field, and that the center of the radiation field coincides with the center of the area where the dose detectors are placed, so as to ensure that each dose detector receives the same amount of radiation dose. However, in the actual screening process, the precise positioning of the placement of the dose detector is a cumbersome process and difficult to implement.

[0003] The Chinese patent document with application number 2019113882510 provides a thermoluminescent irradiation film selection device, which mainly includes an upper cover plate, a lower cover plate, screw holes and a sample slot. There are several sample slots evenly distributed on the lower cover plate, and several screw holes are arranged on the upper cover plate. The upper cover plate and the lower cover plate are connected and fixed by screws passing through the screw holes. It fixes the thermoluminescence in a specific single thermoluminescent film slot, and there will be no overlap during the process of loading into the irradiator, ensuring that the screening results are stable and reliable. Since the device has a relatively wide bottom and flat surroundings, it can be placed in parallel or upright under any radiation irradiation device for effective irradiation. The device can be used for the placement and fixation of thermoluminescent detectors, but is limited by the type and number of detectors placed. At the same time, it is also impossible to adjust the angle of the detector to the rays, and it does not have the function of simple installation and placement and convenient transfer of detectors. In addition, the “Preliminary Experimental Study on Electron Balance in Thermoluminescent Detector Calibration” published in the “Journal of Metrology” in December 2011 clearly stated that materials with electron balance thickness should be provided during the calibration process of thermoluminescent detectors, which cannot be achieved in the above-mentioned comparative documents.

[0004] In view of this, it is necessary to design a radiation dose detector screening system that is suitable for screening various types of detectors and can also select different irradiation angles according to needs, which is convenient for the placement and fixation of various types of detectors, as well as the installation and transfer of detectors, and can be used for batch irradiation, thereby improving screening efficiency. In addition, the outer baffles of different thicknesses can be adjusted according to the different ray energies of the actual irradiation field on site. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a radiation dose detector screening system and screening method.

[0006] In a first aspect, the present application provides a radiation dose detector screening system, which is implemented by adopting the following technical solutions.

[0007] A radiation dose detector screening system comprises a radiation source, a material tray, a base and a pedestal; the radiation source is provided with a laser ranging module; the material tray is a three-layer stacked structure, consisting of two outer baffles and a limit baffle sandwiched therebetween, and the limit baffles include three types; the material tray is fixed on a height-adjustable pedestal through a base; the base comprises a first base and a second base, both of which comprise a bottom plate and a vertical plate, and the two vertical plates clamp the bottom of the material tray to keep the material tray upright; the pedestal comprises a movable base plate, a positioning hole for placing a positioning scale is formed at the center of the movable base plate, and a plurality of angle marking lines radiate from the center of the positioning hole to the surrounding areas.

[0008] Furthermore, the limit baffle plate and the outer baffle plate have the same size, and both are plates with flat surfaces and uniform thickness.

[0009] Furthermore, the base also includes a main base plate, a plurality of support columns are arranged on the edge of the main base plate, threads are formed on the outer walls of the support columns and nuts are embedded therein, and the movable base plate is passed through the plurality of support columns.

[0010] Furthermore, a level bubble is provided on the upper surface of the movable substrate.

[0011] Furthermore, the main body of the positioning ruler is cylindrical, and its outer wall is provided with a first scale line parallel to its central axis and multiple second scale lines perpendicular to the first scale lines; a tray is formed at the lower part of the positioning ruler, and the side wall of the tray forms a third scale line; the central axis, the first scale line, and the third scale line of the positioning ruler are located in the same plane; the value corresponding to each second scale line is the vertical height from the scale line to the bottom of the tray.

[0012] Furthermore, a fourth scale line is provided in the middle of the bottom plates of the first base and the second base.

[0013] Furthermore, the limit baffle includes the following types:

[0014] Type B1: A circular hollow portion is formed in the middle of the limit baffle, a notch is formed on the upper edge of the limit baffle, and the hollow portion is connected to the outside through the notch;

[0015] Type B2: Multiple strip-shaped hollow parts are formed on the limit baffle;

[0016] Type B3: Multiple square hollow parts are formed on the limit baffle;

[0017] Each type of limit baffle is divided into multiple specifications according to the thickness of different types of detectors to be placed; parameter markings are provided on the limit baffle to indicate its thickness and the length L from the center to the bottom edge.

[0018] In a second aspect, the present application provides a radiation dose detector screening method, which is implemented by adopting the following technical solution.

[0019] A radiation dose detector screening method comprises the following steps:

[0020] S1: According to the type and number of dose detectors to be measured, select a limit baffle of appropriate specifications and record its length L parameter; for a B1 type limit baffle, first combine it with an outer baffle, place it on the base and lock it, and put the dose detector in through the notch of the limit baffle; for a B2 or B3 type limit baffle, first place it on an outer baffle, then put the dose detector into its hollow part, cover it with another outer baffle, and finally place the combined tray on the base and lock it;

[0021] S2: Place the base directly in front of the radiation source, and insert the positioning ruler into the positioning hole in the center of the movable base plate; turn on the laser distance measurement module, move the base, and make the light spot hit the positioning ruler; according to the indication of the level bubble, fine-tune the rotating nut to ensure that the base is level; according to the reading of the distance measurement module, adjust the distance between the base and the radiation source to meet the test requirements;

[0022] S3: Rotate the nut to adjust the height of the movable base plate so that the reading value on the second scale line corresponding to the light spot is equal to L; rotate the positioning ruler so that the light spot is located on the first scale line; record the angle identification line corresponding to the third scale line, and use the angle identification line as the reference angle line;

[0023] S4: Remove the positioning ruler, place the base and the tray on the movable base plate, so that the fourth scale line is aligned with the reference angle line recorded in step S3, and the bottom edge of the limit baffle is aligned with another angle identification line perpendicular to the reference angle line;

[0024] S5: Turn on the radiation source, and select a suitable irradiation time according to the size of the irradiation dose to irradiate the dose detector in the tray;

[0025] S6: Turn off the radiation source, take out the dose detector from the tray, measure the detector and read the data; then calculate the average value of the detector readings as the base, select the detectors whose readings are within the range of the average value × (1 ± A%) ± A%, and use the readings as the basis for selecting the detectors with A% consistency, thus completing the screening of dose detectors with a detector consistency of A%.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The material tray of the present invention is suitable for placing various types of dose detectors, is also convenient for batch operation, and the center of the radiation field is easy to locate, which can ensure that all detectors to be screened can be irradiated evenly. The present invention can save processes and improve efficiency for dose detector manufacturers, irradiation units, and dose monitoring units in screening detectors. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a structural schematic diagram of the material tray in the present invention;

[0029] Figure 2 It is a structural schematic diagram of the limit baffle in the present invention (type B1);

[0030] Figure 3 It is a structural schematic diagram of the limit baffle in the present invention (type B2);

[0031] Figure 4 It is a structural schematic diagram of the limit baffle in the present invention (type B3);

[0032] Figure 5 It is a schematic diagram of the structure of the outer baffle in the present invention;

[0033] Figure 6 It is a structural schematic diagram of the base in the present invention (assembled state);

[0034] Figure 7 It is a structural schematic diagram of the base in the present invention (disassembled state);

[0035] Figure 8 It is a structural schematic diagram of the base platform in the present invention;

[0036] Fig. 9 It is a schematic diagram of the structure of the screening system of the present invention;

[0037] Fig.10 It is a structural schematic diagram of the positioning scale in the present invention;

[0038] Fig.11 It is a top view of the adjustable B1 type limit baffle in the present invention;

[0039] Fig.12 It is a structural schematic diagram of the annular baffle in the present invention;

[0040] Fig.13 It is a schematic structural diagram of the material tray and the base after being combined in the present invention.

[0041] Among them, 1. limit baffle; 101. annular baffle; 2. outer baffle; 3. first base; 4. second base; 5. counterweight; 6. movable base plate; 7. support column; 8. main base plate; 9. nut; 10. level bubble; 11. radiation source; 12. positioning scale; 13. angle marking line; 14. tray; 15. third scale line; 16. fourth scale line. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0043] like Figures 1 to 13 As shown, a radiation dose detector screening system includes a radiation source 11, a tray, a base and a base; the radiation source 11 is provided with a laser ranging module; the tray is a rectangular three-layer stacked structure, consisting of two outer baffles 2 and a limit baffle 1 sandwiched therebetween, and the limit baffle 1 includes three types; the tray is fixed on a height-adjustable base through a base; the base includes a first base 3 and a second base 4, both of which include a bottom plate and a vertical plate, and the two vertical plates clamp the bottom of the tray to keep the tray upright; the base includes a movable base plate 6, and a positioning hole for placing a positioning scale 12 is formed in the center of the movable base plate 6, and multiple angle marking lines 13 radiate from the center of the positioning hole to the surrounding area. The base is placed on a horizontal table, and the overall weight is relatively heavy, which is conducive to the stability of the tray placement. There are as many angle marking lines 13 as possible, at least one every 10°, and the position of the line end is marked with the corresponding angle value, which is convenient for finding when using.

[0044] The length and width of the limit baffle 1 and the outer baffle 2 are the same, and both are plates with a flat surface and uniform thickness. The limit baffle 1 and the outer baffle 2 are provided with a plurality of fixing holes with matching shapes and positions on the four sides, and can be clamped by bolts and nuts to achieve fixation when the material tray is assembled. The outer baffle 2 can be set in a variety of specifications according to different thicknesses, and a suitable outer baffle 2 can be selected according to different types of radiation sources when in use.

[0045] The base also includes a main base plate 8, and a plurality of support columns 7 are arranged on the upper edge of the main base plate 8. The outer wall of the support column 7 is threaded and embedded with a nut 9. The top of the support column 7 passes through the movable base plate 6, and the movable base plate 6 is mounted on the nut 9. The upper surface of the movable base plate 6 is smooth and flat, and is used to place the base.

[0046] The first base 3 and the second base 4 are both provided with a counterweight 5. Two limit grooves are formed on the vertical plate of the first base 3, and side baffles matching the shape and position of the limit grooves are formed on the vertical plate of the second base 4; the two side baffles clamp the material tray from the side. The function of the counterweight is to make the entire device more stable; the side baffles are inserted into the limit grooves, so that after the material tray is placed in the base, the two side baffles and the two vertical plates clamp the bottom of the material tray from four sides, so that the material tray remains upright and has higher stability. The vertical plate is also provided with fixing holes that are consistent in size and shape with the fixing holes on the lower edges of the limit baffle 1 and the outer baffle 2, so as to facilitate overall fixation by bolts and nuts.

[0047] A level bubble 10 is provided on the upper surface of the movable base plate 6. According to the indication of the level bubble 10, the rotating nut 9 is fine-tuned to ensure that the base is level.

[0048] The main body of the positioning ruler 12 is cylindrical, and its outer wall is provided with a first scale line parallel to its central axis and multiple second scale lines perpendicular to the first scale lines; a tray 14 is formed at the lower part of the positioning ruler 12, and the side wall of the tray 14 forms third scale lines 15; the central axis, first scale lines, and third scale lines 15 of the positioning ruler 12 are located in the same plane; the reading corresponding to each second scale line is the vertical height difference from the scale line to the bottom surface of the tray 14.

[0049] A fourth scale line 16 is provided in the middle of the bottom plates of the first base 3 and the second base 4 , corresponding to the angle marking line 13 , to adjust the desired irradiation angle.

[0050] The limit baffle 1 includes the following types:

[0051] Type B1: A circular hollow portion is formed in the middle of the limit baffle 1, and a notch is formed on the upper edge of the limit baffle 1. The hollow portion is connected to the outside through the notch; the notch can be used to place a radiation dose detector;

[0052] Type B2: Multiple strip-shaped hollow portions are formed on the limit baffle 1;

[0053] Type B3: A plurality of square hollow portions are formed on the limit baffle 1;

[0054] Each type of limit baffle 1 is divided into multiple specifications according to different thicknesses; the limit baffle 1 is provided with parameter markings for indicating its thickness and the length L from the center to the bottom edge. The principle of selecting the limit baffle 1 is to make the height of the radiation dose detector to be measured slightly smaller than the thickness of the limit baffle 1. The reason for this selection is: if the height of the radiation dose detector is greater than the thickness of the limit baffle 1, the radiation dose detector cannot be placed in the material tray; and if the height of the radiation dose detector is much smaller than the thickness of the limit baffle 1, it may cause the radiation dose detector to be unevenly arranged due to overlap.

[0055] A radiation dose detector screening method comprises the following steps:

[0056] S1: According to the type and number of dose detectors to be measured, select a limit baffle 1 of appropriate specifications and record its length L parameter; for a B1 type limit baffle 1, first combine it with an outer baffle 2, place it in the base and lock it, and put the dose detector into the notch formed by the upper edge of the limit baffle 1; for a B2 or B3 type limit baffle 1, first place it on an outer baffle 2, then put the dose detector into its hollow part, cover it with another outer baffle 2, and finally place the combined tray in the base and lock it;

[0057] S2: Deploy the base in front of the radiation source 11, insert the positioning scale 12 into the positioning hole in the center of the movable base plate 6; turn on the laser ranging module, move the base so that the light spot hits the positioning scale 12; fine-tune the rotating nut 9 according to the indication of the level bubble 10 to adjust the level of the base; adjust the distance between the base and the radiation source 11 according to the reading of the ranging module to meet the test requirements;

[0058] S3: Rotate the nut 9 to adjust the height of the movable base plate 6 so that the reading value on the second scale line corresponding to the light spot is equal to L; rotate the positioning ruler 12 so that the light spot is located on the first scale line; in this step, the movable base plate 6 should be adjusted according to the indication of the level bubble 10 to ensure that the final state of the movable base plate 6 is horizontal; record the angle identification line 13 corresponding to the third scale line 15, and use the angle identification line 13 as the reference angle line;

[0059] S4: Remove the positioning ruler 12, place the base and the tray on the movable base plate 6, so that the fourth scale line 16 is aligned with the reference angle line recorded in step S3, and the limit stopper 1 is located on another angle identification line 13 perpendicular to the reference angle line;

[0060] like Fig.13 As shown, after the material tray and the base are combined, they are placed on the movable base plate 6. AA' and BB' in the figure are both angle identification lines 13, and AA' and BB' are perpendicular to each other (for the convenience of description, the other angle identification lines 13 are not drawn in the figure). In the adjustment process described in step S3, AA' is used as the reference angle line, and the limit baffle 1 is located on BB';

[0061] S5: Turn on the radiation source 11, and select a suitable irradiation time according to the size of the irradiation dose to irradiate the dose detector in the tray;

[0062] S6: Turn off the radiation source 11, take out the dose detector in the tray, measure the detector, and read the data; then calculate the average value of the detector readings, and use the detectors with readings in the range of the average value × (1 ± A%) as the basis for selecting A% consistency detectors to complete the screening of detectors. After one irradiation is completed, sum the readings of all detectors and divide them by their number to get the average value Do of the readings. Then define the detectors with readings in the range of (1 ± A%) × Do as detectors with A% consistency, and A can be 1, 2, 3, 4, 5 or 10. If A is 1, the detectors with readings in the range of (1-1%) × Do to (1+1%) × Do are detectors with 1% consistency; if A is 2, the detectors with readings in the range of (1-2%) × Do to (1+2%) × Do are detectors with 2% consistency.

[0063] Embodiment 1:

[0064] Among the three types of limit baffles 1, type B1 is the most commonly used. When in use, the irradiated detectors should be concentrated as much as possible in the hollow portion in the middle of the limit baffle 1. It is best to just fill the area. Since the number of screening dose detectors is not fixed, the area of ​​the hollow portion in the middle of the limit baffle 1 can be made adjustable as needed. Fig.11 As shown, the middle of the B1 type limit baffle 1 can be filled with a plurality of annular baffles 101 with gaps of different sizes. The structure of the annular baffle 101 is as shown in FIG. Fig.12 As shown, the width of each ring ranges from 5 mm to 1 cm. If the number of detectors to be irradiated is small, increasing the number of annular baffles 101 will reduce the area of ​​the hollow portion in the middle; conversely, reducing the number of annular baffles 101 will increase the area of ​​the hollow portion in the middle.

[0065] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A radiation dose detector screening system, comprising a radiation source (11), a tray, a base and a base; the radiation source (11) is provided with a laser ranging module; characterized in that: The material tray is a three-layer stacked structure, consisting of two outer baffles (2) and a limit baffle (1) sandwiched therebetween, wherein the limit baffle (1) includes three types; the material tray is fixed to a height-adjustable base via a base; the base includes a first base (3) and a second base (4), each of which includes a bottom plate and a vertical plate, wherein the two vertical plates clamp the bottom of the material tray to keep the material tray upright; the base includes a movable base plate (6), a positioning hole for placing a positioning scale (12) is formed at the center of the movable base plate (6), and a plurality of angle marking lines (13) radiate from the center of the positioning hole to the surrounding areas; The main body of the positioning ruler (12) is cylindrical, and its outer wall is provided with a first scale line parallel to its central axis and a plurality of second scale lines perpendicular to the first scale lines; a tray (14) is formed at the lower part of the positioning ruler (12), and a third scale line (15) is formed on the side wall of the tray (14); the central axis, the first scale line, and the third scale line (15) of the positioning ruler (12) are located in the same plane; and the value corresponding to each second scale line is the vertical height from the scale line to the bottom surface of the tray (14); A fourth scale line (16) is provided in the middle of the bottom plates of the first base (3) and the second base (4).

2. A radiation dose detector screening system as claimed in claim 1, characterized in that: The limit baffle (1) and the outer baffle (2) have the same size and are both plates with a flat surface and uniform thickness.

3. A radiation dose detector screening system as claimed in claim 1, characterized in that: The base also comprises a main base plate (8), a plurality of support columns (7) are arranged at the edge of the main base plate (8), threads are formed on the outer walls of the support columns (7) and nuts (9) are embedded therein, and the movable base plate (6) is inserted through the plurality of support columns (7).

4. A radiation dose detector screening system as claimed in claim 3, characterized in that: A level bubble (10) is provided on the upper surface of the movable base plate (6).

5. A radiation dose detector screening system as claimed in claim 4, characterized in that: The limit baffle (1) includes the following types: Type B1: A circular hollow portion is formed in the middle of the limit baffle (1), a notch is formed on the upper edge of the limit baffle (1), and the hollow portion is connected to the outside through the notch; Type B2: A plurality of strip-shaped hollow portions are formed on the limit baffle (1); Type B3: A plurality of square hollow portions are formed on the limit baffle (1); Each type of limit baffle (1) is classified into a plurality of specifications according to the thickness of different types of detectors to be placed; each limit baffle (1) is provided with a parameter mark indicating its thickness and the length L from the center to the bottom edge.

6. A method for screening radiation dose detectors, characterized in that: Using the radiation dose detector screening system described in claim 5, the screening method comprises the following steps: S1: According to the type and number of dose detectors to be measured, select a limit baffle (1) of appropriate specifications and record its length L parameter; for a B1 type limit baffle (1), first combine it with an outer baffle (2), place it on the base and lock it, and insert the dose detector from the notch of the limit baffle (1); for a B2 or B3 type limit baffle (1), first place it on an outer baffle (2), then insert the dose detector into the hollow part, cover it with another outer baffle (2), and finally place the combined material tray on the base and lock it; S2: The base is placed in front of the radiation source (11), and the positioning scale (12) is inserted into the positioning hole in the center of the movable base plate (6); the laser distance measurement module is turned on, and the base is moved so that the light spot is projected onto the positioning scale (12); according to the indication of the level bubble (10), the fine adjustment nut (9) is rotated to adjust the level of the base; according to the reading of the distance measurement module, the distance between the base and the radiation source (11) is adjusted to meet the test requirements; S3: Rotate the nut (9) to adjust the height of the movable base plate (6) so that the reading value on the second scale line corresponding to the light spot is equal to L; rotate the positioning ruler (12) so that the light spot is located on the first scale line; record the angle identification line (13) corresponding to the third scale line (15), and use the angle identification line (13) as the reference angle line; S4: Remove the positioning ruler (12), place the base and the material tray on the movable base plate (6), so that the fourth scale line (16) is aligned with the reference angle line recorded in step S3, and the bottom edge of the limit baffle (1) is aligned with another angle identification line (13) perpendicular to the reference angle line; S5: Turn on the radiation source (11), and select a suitable irradiation time according to the size of the irradiation dose to irradiate the dose detector in the tray; S6: Turn off the radiation source (11), take out the dose detector from the tray, measure the detector, and read the data; then calculate the average value of the detector readings, select the detector whose reading is within the range of the average value × (1 ± A%), and complete the screening of dose detectors with a consistency of A%.

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