An irradiation device and a method for testing the performance of a radiation detector and a scintillation crystal.

Abstract

This invention discloses an irradiation device and a method for testing the performance of radiation detectors and scintillation crystals. The irradiation device includes a housing with several horizontally arranged partitions inside, spaced vertically to divide the housing into several chambers. Each chamber contains an irradiation unit. Each irradiation unit includes a rotating mechanism with a placement slot for placing a radiation source. The rotating mechanism is horizontally rotatable. An operating port is provided on one side wall of the housing, allowing the placement slot to extend out of the housing after the rotating mechanism rotates at a certain angle, facilitating the replacement of the radiation source within the placement slot. The bottom plate of the housing and all partitions have collimation holes corresponding to the placement slots, ensuring that the placement slots are positioned directly above the collimation holes after the rotating mechanism rotates, and all collimation holes are aligned on the same straight line. This invention can be used for scintillation crystal performance testing, radiation detector calibration, and scaling experiments, and can effectively reduce radiation damage to workers.

Description

Technical Field

[0001] This invention belongs to the field of nuclear radiation detection technology, and relates to an irradiation device and a method for testing the performance of radiation detectors and scintillation crystals. Background Technology

[0002] In scintillation crystal performance testing, an exempt source or a Class V source is required for irradiation to obtain performance parameters such as light output intensity, emission decay time, and energy resolution. Researchers often use a photomultiplier tube (PMT) to couple the crystal to the test crystal during parameter testing experiments. The procedure is as follows: open the PMT's shield, place the crystal on the PMT's optical window and cover it with the shield to block the light, then place the radiation source on the PMT's shield perpendicular to the PMT. When measuring large batches of crystals, these steps need to be repeated, and there is a risk of radiation damage during crystal replacement.

[0003] Furthermore, radiation detectors require various energy radiation sources to acquire radiation information when conducting experiments such as detection efficiency calibration, angular response studies, and energy calibration. For example, in the energy calibration of gamma-ray spectrometers, standard calibration gamma sources (including...) are often used. 60 Co、 137 Cs、 40 K, 238 U、 232 Th) The instrument is calibrated for energy (Table 1), but there are problems such as radiation damage and loss of radioactive source during the handling of radioactive source.

[0004] Table 1. Several standard radiation sources used for energy calibration.

[0005]

[0006] Therefore, developing an irradiation device that can be used for crystal performance testing while also meeting the requirements for radiation detector calibration and scaling is of great significance for detector development, nuclear industry development, and radiation safety of radiation personnel.

[0007] During crystal testing and detector calibration, two requirements need to be considered for irradiation devices: First, when testing the performance of scintillation crystals, exemption sources or Class V gamma radiation sources are required. During scientific experiments, staff need to frequently change the crystals and be exposed to radiation sources for extended periods. Even with current operating procedures, protective measures are insufficient to prevent the cumulative dose received from prolonged irradiation. Second, during the calibration of radiation detectors, multiple radiation sources are needed for energy calibration. Furthermore, the calibration of gamma-ray angular response and detection efficiency may require multiple radiation sources for experimental calibration. Summary of the Invention

[0008] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide an irradiation device and a method for testing the performance of radiation detectors and scintillation crystals. This invention can be used for scintillation crystal performance testing, radiation detector calibration and scaling experiments, and can effectively reduce radiation damage to workers and improve the radiation safety of workers.

[0009] The technical solution of this invention is implemented as follows:

[0010] An irradiation device includes a housing with several horizontally arranged partitions inside the housing. All the partitions are spaced vertically to divide the housing into several chambers, and each chamber contains an irradiation unit.

[0011] The irradiation unit includes a rotating mechanism with a placement slot for placing a radiation source. The rotating mechanism can rotate horizontally and has an operating port on one side wall of the housing. This allows the placement slot to extend out of the housing after the rotating mechanism rotates to a certain angle, facilitating the replacement of the radiation source in the placement slot by the operator. The bottom plate of the housing and all partitions have alignment holes that correspond one-to-one with the placement slots. This ensures that the placement slot is positioned directly above the alignment holes after the rotating mechanism rotates, and all alignment holes are aligned on the same straight line.

[0012] Furthermore, the rotating mechanism includes an operating lever, a guide rail, a rack, a rotating gear, and a rotating plate. The guide rail is disposed on a partition or bottom plate inside the housing on the side opposite to the alignment hole, and is parallel to the corresponding inner wall of the housing. The rack is slidably disposed on the guide rail. The rotating gear is rotatably disposed between the guide rail and the alignment hole via a rotating shaft, which is vertically disposed on the corresponding partition or bottom plate of the housing. The rotating gear meshes with the rack. One end of the rotating plate is connected to the rotating gear to rotate with the rotating gear. The placement groove is disposed at the other end of the rotating plate. One end of the operating lever is connected to the rack. A strip-shaped hole is horizontally provided on the side wall of the housing for the operating lever to pass through. The strip-shaped hole is parallel to the guide rail. The other end of the operating lever extends out of the housing, making it convenient for the operator to push and pull the operating lever, causing the rack to slide on the guide rail, thereby driving the rotating plate to rotate.

[0013] Furthermore, the bottom of the placement tank is made of plastic film, and the four walls are made of tungsten alloy.

[0014] Furthermore, a calibration mechanism is provided inside the box to ensure that the center axis of the placement slot and the collimation hole are on the same straight line.

[0015] Furthermore, the calibration mechanism is a spring pin.

[0016] Furthermore, shielding pins are detachably provided at the operating port, the strip hole, and the alignment hole on the bottom plate of the box.

[0017] This invention also provides a method for batch testing of radiation detectors using an irradiation device, employing the aforementioned irradiation device, specifically including the following steps:

[0018] (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use.

[0019] (2) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole.

[0020] (3) Place the radiation detector in the position to be tested and align the collimation hole on the bottom plate of the box with the radiation detector; remove the shielding pin at the collimation hole to test the radiation detector.

[0021] (4) After completing the test of a radiation detector, replace the radiation detector and repeat step (3); in this way, complete the test of radiation detectors in batches.

[0022] This invention also provides a method for batch testing of scintillation crystal performance using an irradiation device, employing the aforementioned irradiation device, specifically including the following steps:

[0023] (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use.

[0024] (2) Connect the robotic arm and the irradiation device, and control the robotic arm to align the collimation hole on the bottom plate of the box with the photomultiplier tube;

[0025] (3) Open the light shield of the photomultiplier tube, place the scintillation crystal in the center of the photomultiplier tube's light window, and cover it with the light shield to block the light.

[0026] (4) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole and open the shielding pin at the collimation hole to test the performance of the scintillation crystal.

[0027] (5) After the scintillation crystal test is completed, remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate so that the radiation source is not directly opposite the collimation hole, and then install the shielding pin at the strip hole.

[0028] Alternatively, the robotic arm can be adjusted to align the collimation hole with other safe areas.

[0029] (6) Repeat steps (3) to (4) to complete the scintillation crystal performance test; or repeat step (3) and adjust the robotic arm so that the collimation hole is aligned with the photomultiplier tube to complete the scintillation crystal performance test.

[0030] (7) Repeat steps (5) to (6) to complete the scintillation crystal performance test in batches.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. This irradiation device contains multiple irradiation units and can store multiple radiation sources. All collimating apertures of this irradiation device face one direction, effectively controlling the radiation beam. During use, multiple radiation sources can be pre-placed inside the enclosure as needed to test the radiation detector. Furthermore, during operation, the rotating mechanism can be rotated to place unused radiation sources into an idle state. Due to the collimating aperture design, radiation damage to workers is effectively reduced, improving their radiation safety. When performing performance testing on the scintillation crystal, the collimating apertures prevent workers from being directly exposed to radiation during crystal replacement.

[0033] 2. This invention can perform performance tests on radiation detectors and scintillator crystal strips in batches. It is easy and flexible to operate, which helps to improve work efficiency, reduce radiation damage to workers during the replacement of scintillator crystals, and improve the radiation safety of workers. Attached Figure Description

[0034] Figure 1 - A schematic diagram of the external structure of the irradiation device.

[0035] Figure 2 - A schematic diagram of the internal structure of the irradiation device.

[0036] Figure 3 - A schematic diagram of the structure of a radioactive source in operation.

[0037] Wherein: 1-box body; 2-shielding pin at the operating port; 3-operating lever; 4-shielding pin at the strip hole; 5-partition or bottom plate of the box body; 6-collimation hole; 7-calibration mechanism; 8-operating port; 9-plastic film; 10-high-density tungsten alloy; 11-rotating plate; 12-rack; 13-guide rail; 14-positioning block; 15-rotating gear; 16-rotating shaft. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0039] See Figure 1 , Figure 2 and Figure 3 An irradiation device includes a housing 1, with several partitions 5 horizontally arranged inside the housing 1. All partitions 5 are spaced vertically to divide the housing 1 into several chambers, and an irradiation unit is provided in each chamber.

[0040] The irradiation unit includes a rotating mechanism with a placement slot for placing a radioactive source. The rotating mechanism can rotate horizontally. An operating port 8 is provided on one side wall of the housing 1, which allows the placement slot to extend out of the housing 1 from the operating port 8 after the rotating mechanism rotates at a certain angle, so that the staff can replace the radioactive source in the placement slot. The bottom plate 5 of the housing and all partitions 5 are provided with collimation holes 6 that correspond one-to-one with the placement slots, so that the placement slot is positioned directly above the collimation holes 6 after the rotating mechanism rotates, and all collimation holes 6 are located on the same straight line.

[0041] The enclosure here is made of shielding material to shield radiation. When it is necessary to replace or place a radiation source, the rotating mechanism extends the placement slot out of the operating port for easy operation. When the rotating mechanism rotates into the enclosure and aligns the placement slot with the collimation hole, it is in the working state. When the rotating mechanism rotates into the side of the enclosure away from the operating port, the radiation source placed in the corresponding placement slot is in an idle state.

[0042] This device contains multiple irradiation units and can store multiple radioactive sources (such as Category V sources or exempted sources, primarily for...). 137 Cs、 60 (Co, etc.) Furthermore, all collimating apertures of this device face one direction, effectively controlling the radiation beam. During use, multiple radiation sources can be pre-placed inside the housing as needed to test the radiation detector. During operation, the rotating mechanism can be rotated to idle unused radiation sources. Due to the collimating aperture design, radiation damage to workers is effectively reduced, improving their radiation safety. When performing performance tests on the scintillation crystal, the collimating apertures prevent workers from receiving direct radiation exposure during crystal replacement.

[0043] The partition here can effectively prevent radiation from the radioactive source in the vertical direction when it is not in use, thus improving the accuracy of the test results.

[0044] In specific implementation, the rotating mechanism includes an operating lever 3, a guide rail 13, a rack 12, a rotating gear 15, and a rotating plate 11. The guide rail 13 is disposed on a partition plate 5 or a bottom plate 5 of the housing 1 on the side opposite to the alignment hole 6, and is parallel to the corresponding inner wall of the housing 1. The rack 12 is slidably disposed on the guide rail 13, and the rotating gear 15 is rotatably disposed between the guide rail 13 and the alignment hole 6 via a rotating shaft 16, which is vertically disposed on the corresponding partition plate 5 or bottom plate 5. The rotating gear 15 meshes with the rack 12. One end of the rotating plate 11 is connected to the rotating gear 15 so that it rotates with the rotating gear 15. The placement groove is provided at the other end of the rotating plate 11. One end of the operating rod 3 is connected to the rack 12. A strip-shaped hole is provided horizontally on the side wall of the box body 1 for the operating rod 3 to pass through. The strip-shaped hole is parallel to the guide rail 13. The other end of the operating rod 3 extends out of the box body 1, which makes it convenient for the staff to push and pull the operating rod 3, so that the rack 12 slides on the guide rail 13, thereby driving the rotating plate 11 to rotate.

[0045] The above-described placement slot is one embodiment. Alternatively, a through hole can be made in the rotating plate to place the placement slot, as shown in the example below. Figure 2 and Figure 3 Positioning blocks 14 are also provided at both ends of the guide rail to position the guide rail on the partition or the bottom plate of the box.

[0046] In this way, the operator can slide the rack on the slide rail by operating the lever. The sliding rack drives the rotating gear to rotate, which in turn drives the rotating plate to adjust the position of the placement slot, so that the radiation source in the placement slot is in different states. The whole operation process is flexible and convenient.

[0047] In practice, the bottom of the placement tank is made of plastic film 9, and the four walls are made of high-density tungsten alloy 10.

[0048] The high-density tungsten alloy here can effectively shield horizontal gamma rays.

[0049] In practice, a calibration mechanism 7 is provided inside the housing to ensure that the central axes of the placement slot and the alignment hole 6 are on the same straight line. The calibration mechanism 7 is a spring pin.

[0050] In this way, when adjusting the position of the placement slot, the calibration mechanism will make a sound when the placement slot is aligned with the collimation hole, reminding the staff to make the adjustment in place.

[0051] In practice, shielding pins are detachably provided at the operating port 8, the strip hole and the alignment hole 6 on the bottom plate 5 of the box, namely shielding pin 2 at the operating port, shielding pin 4 at the strip hole and shielding pin at the alignment hole (not shown in the figure).

[0052] Here, installing shielding pins can effectively reduce the radiation exposure of workers from the radiation source.

[0053] A method for batch testing of radiation detectors using an irradiation device, employing the aforementioned irradiation device, specifically includes the following steps:

[0054] (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use.

[0055] (2) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole.

[0056] (3) Place the radiation detector in the position to be tested and align the collimation hole on the bottom plate of the box with the radiation detector; remove the shielding pin at the collimation hole to test the radiation detector.

[0057] (4) After completing the test of a radiation detector, replace the radiation detector and repeat step (3); in this way, complete the test of radiation detectors in batches.

[0058] A method for batch testing of scintillation crystal performance using an irradiation device, comprising the following steps:

[0059] (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use.

[0060] (2) Connect the robotic arm and the irradiation device, and control the robotic arm to align the collimation hole on the bottom plate of the box with the photomultiplier tube;

[0061] (3) Open the light shield of the photomultiplier tube, place the scintillation crystal in the center of the photomultiplier tube's light window, and cover it with the light shield to block the light.

[0062] (4) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole and open the shielding pin at the collimation hole to test the performance of the scintillation crystal.

[0063] (5) After the scintillation crystal test is completed, remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate so that the radiation source is not directly opposite the collimation hole, and then install the shielding pin at the strip hole.

[0064] Alternatively, the robotic arm can be adjusted to align the collimation hole with other safe areas.

[0065] (6) Repeat steps (3) to (4) to complete the scintillation crystal performance test; or repeat step (3) and adjust the robotic arm so that the collimation hole is aligned with the photomultiplier tube to complete the scintillation crystal performance test.

[0066] (7) Repeat steps (5) to (6) to complete the scintillation crystal performance test in batches.

[0067] Before conducting batch testing of the radiation detector and scintillation crystal, multiple commonly used radiation sources can be pre-placed within the irradiation device as needed. During use, one or more radiation sources are selected as required, aligning them directly with the corresponding collimation aperture. After batch testing, all radiation sources aligned with the collimation aperture are rotated to other areas of the enclosure that are not aligned with the collimation aperture, rendering the radiation sources idle. Then, all shielding pins are installed.

[0068] Finally, it should be noted that the above embodiments of the present invention are merely illustrative examples and not intended to limit the implementation of the invention. Those skilled in the art can make other variations and modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of this invention are still within the scope of protection of this invention.

Claims

1. An irradiation device, characterized in that, It includes a housing, inside which several horizontal partitions are arranged. All the partitions are spaced vertically to divide the housing into several chambers, and each chamber contains an irradiation unit. The irradiation unit includes a rotating mechanism with a placement slot for placing a radiation source. The rotating mechanism can rotate horizontally and has an operating port on one side wall of the housing. This allows the placement slot to extend out of the housing after the rotating mechanism rotates to a certain angle, facilitating the replacement of the radiation source in the placement slot by the operator. The bottom plate of the housing and all partitions have alignment holes that correspond one-to-one with the placement slots. This ensures that the placement slot is positioned directly above the alignment holes after the rotating mechanism rotates, and all alignment holes are aligned on the same straight line.

2. The irradiation device according to claim 1, characterized in that, The rotating mechanism includes an operating lever, a guide rail, a rack, a rotating gear, and a rotating plate. The guide rail is set on a partition or bottom plate inside the box on the side opposite to the alignment hole, and is parallel to the corresponding inner wall of the box. The rack is slidably mounted on the guide rail. The rotating gear is rotatably mounted between the guide rail and the alignment hole via a rotating shaft, which is vertically mounted on the corresponding partition or bottom plate. The rotating gear meshes with the rack. One end of the rotating plate is connected to the rotating gear to rotate with it. The placement groove is located at the other end of the rotating plate. One end of the operating lever is connected to the rack. A strip-shaped hole is horizontally provided on the side wall of the box for the operating lever to pass through. The strip-shaped hole is parallel to the guide rail. The other end of the operating lever extends out of the box, making it easy for the operator to push and pull the operating lever, causing the rack to slide on the guide rail, thereby driving the rotating plate to rotate.

3. The irradiation device according to claim 2, characterized in that, The bottom of the placement tank is made of plastic film, and the four walls are made of tungsten alloy.

4. An irradiation device according to claim 2, characterized in that, A calibration mechanism is provided inside the box to ensure that the center axis of the placement slot and the collimation hole are on the same straight line.

5. An irradiation device according to claim 4, characterized in that, The calibration mechanism is a spring pin.

6. An irradiation device according to claim 2, characterized in that, The operating port, the strip hole, and the alignment hole on the bottom plate of the box are each equipped with a detachable shielding pin.

7. A method for batch testing radiation detectors in an irradiation device, characterized in that, The testing using the irradiation apparatus of claim 6 specifically includes the following steps: (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use. (2) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole. (3) Place the radiation detector in the position to be tested and align the collimation hole on the bottom plate of the box with the radiation detector; remove the shielding pin at the collimation hole to test the radiation detector. (4) After completing the test of a radiation detector, replace the radiation detector and repeat step (3); in this way, complete the test of radiation detectors in batches.

8. A method for batch testing the performance of scintillation crystals using an irradiation device, characterized in that, The testing using the irradiation apparatus of claim 6 specifically includes the following steps: (1) Remove the shielding pins at the operating port and the strip hole, operate the operating lever and rotate the rotating plate so that the placement slot extends out of the box, place the radioactive source in the placement slot, operate the operating lever and rotate the rotating plate so that the placement slot enters the box and is not directly opposite the collimation hole, and then install the shielding pins at the operating port and the strip hole; follow these steps to place all the radioactive sources for later use. (2) Connect the robotic arm and the irradiation device, and control the robotic arm to align the collimation hole on the bottom plate of the box with the photomultiplier tube; (3) Open the light shield of the photomultiplier tube, place the scintillation crystal in the center of the photomultiplier tube's light window, and cover it with the light shield to block the light. (4) Remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate, and rotate the radiation source to be used to the collimation hole so that the radiation source is aligned with the collimation hole. Then install the shielding pin at the strip hole and open the shielding pin at the collimation hole to test the performance of the scintillation crystal. (5) After the scintillation crystal test is completed, remove the shielding pin at the strip hole, operate the operating lever, rotate the rotating plate so that the radiation source is not directly opposite the collimation hole, and then install the shielding pin at the strip hole. Alternatively, the robotic arm can be adjusted to align the collimation hole with other safe areas. (6) Repeat steps (3) to (4) to complete the scintillation crystal performance test; or repeat step (3) and adjust the robotic arm so that the collimation hole is aligned with the photomultiplier tube to complete the scintillation crystal performance test. (7) Repeat steps (5) to (6) to complete the scintillation crystal performance test in batches.

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