Low background alpha-gamma energy spectrum composite measuring device

Abstract

The utility model discloses a low-background alpha-gamma energy spectrum composite measuring device, and belongs to the technical field of nuclear radiation measuring devices. The low-background alpha-gamma energy spectrum composite measurement device comprises a lead shielding layer, a lead shielding cover, a compression bar type hinge, a base, a lifting motor, a detector fixing frame, an alpha detector, a gamma detector and a pull-out sample table, the detector fixing frame can ascend and descend in the lead shielding layer, and an alpha detector, a drawing type sample table and a gamma detector are installed on the detector fixing frame; the liftable detector fixing frame can be used for realizing convenient sample replacement, and meanwhile, the relative positions of the alpha detector, the gamma detector and the sample can be kept fixed, so that the detection efficiency is kept unchanged. The low-background alpha-gamma energy spectrum composite measurement device is reasonable in design and convenient to use, alpha-ray and gamma-ray energy spectrum composite measurement of the sample can be realized, the radionuclide measurement range is expanded, alpha and gamma radionuclides in the sample can be qualitatively identified, and the radioactive activity of the sample can be quantitatively calculated.

Description

Technical Field

[0001] This utility model relates to the field of radiation measurement device technology, and in particular to a low-background α-γ energy spectrum composite measurement device. Background Technology

[0002] The low-background α-γ energy spectrum combined measurement device can be used for the identification and activity measurement of radionuclides in filter membrane samples and planar source samples, and can simultaneously measure α and γ radionuclides. Conventional γ measuring instruments require a lead layer as a shield to achieve low-background environment measurement, and the γ detector is installed and fixed inside the lead layer. Due to the bulky structure of the lead layer, it is inconvenient to install other detectors, especially α detectors with short detection distances, which can only analyze and measure γ radionuclides.

[0003] Therefore, there is a need to develop a low-background α-γ energy spectrum composite measurement device to realize α-γ energy spectrum composite measurement, expand the measurement range of radionuclides, and at the same time, with the help of characteristic nuclides, it is possible to perform secondary verification of α and γ detection efficiency, effectively calibrate detection efficiency, and improve measurement accuracy. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a low-background α-γ energy spectrum composite measurement device with reasonable structure and convenient use, which can realize the analysis and measurement of α and γ radionuclide samples.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0006] This utility model provides a low-background α-γ energy spectrum composite measurement device, including a lead shielding layer 1, a lead shielding cover 2, a base 4, a lifting motor 5, a detector fixing frame 6, an α detector 7, a γ detector 8, and a pull-out sample stage 9.

[0007] The lead shielding layer 1 is a hollow cylinder made of metallic lead; one end of the lead shielding layer 1 is mounted on a base 4, which is a plane with a hole communicating with the cavity of the lead shielding layer 1; the lead shielding cover 2 is mounted on the upper end of the lead shielding layer 1 via an opening and closing mechanism, and can be rotated and opened in the horizontal direction.

[0008] The lifting motor 5 includes a motor body and a lifting platform. The motor body is installed below the base 4, and the lifting platform is connected to the motor body. The motor body controls the vertical lifting of the lifting platform inside the cylindrical hollow cavity of the lead shielding layer 1. The detector mounting bracket 6 is installed and fixed above the lifting platform of the lifting motor 5. The detector mounting bracket 6 has an α detector mounting slot, a pull-out sample stage slot, and a γ detector mounting slot in its upper, middle, and lower parts, respectively. The α detector 7 is installed in the α detector mounting slot in the upper part of the detector mounting bracket 6 with its detection surface facing down. The γ detector 8 is installed in the γ detector mounting slot in the lower part of the detector mounting bracket 6 with its detection surface facing up. The pull-out sample stage 9 is horizontally embedded in the pull-out sample stage slot in the middle layer of the detector mounting bracket 6.

[0009] Preferably, the three surfaces of the α detector 7, the γ detector 8, and the pull-out sample stage 9 are horizontally parallel and their center points are coaxial.

[0010] Furthermore, the distance between the pull-out sample stage 9 and the bottom detection surface of the α detector 7 is no more than 3 cm, and the distance between it and the upper detection surface of the γ detector 8 is no more than 10 cm.

[0011] Preferably, the lead shielding layer 1 is a hollow cylinder with a thickness of not less than 10 cm.

[0012] Furthermore, the lead shielding cover 2 has a thickness of not less than 10 centimeters.

[0013] Preferably, the opening and closing mechanism is a lever-type hinge 3.

[0014] Preferably, the outer surface of the lead shielding layer 1 is coated with copper metal.

[0015] Preferably, the base 4 is provided with a support foot at the bottom, connecting the base 4 to the ground.

[0016] Furthermore, there are four support legs in total, with reinforcing ribs between each pair of adjacent legs.

[0017] Furthermore, a connecting plate is provided between a pair of opposing reinforcing ribs to support and limit the lifting motor 5.

[0018] The beneficial effects of this utility model are:

[0019] The lead shielding layer 1 and lead shielding cover 2 can shield external noise signals and improve the accuracy of gamma measurement. The α detector 7, γ detector 8 and pull-out sample stage 9 are all mounted on the detector mounting bracket 6 and can be raised and lowered by the lifting motor 5. With the opening and closing of the lead shielding cover 2, the sample can be replaced, and the relative position of the sample with the α detector 7 and γ detector 8 remains unchanged, thereby maintaining the detection efficiency.

[0020] During the measurement, the lead shielding cover 2 is closed, the lifting motor 5 is in a low position, and the detector mounting bracket 6, along with the α detector 7, γ detector 8, and pull-out sample stage 9 mounted on it, are all inside the lead shielding layer 1. After the measurement, the lead shielding cover 2 can be unscrewed, the lifting motor raised, and the pull-out sample stage 9 lifted above the lead shielding layer 1. The pull-out sample stage 9 can then be pulled out from the slot of the detector mounting bracket 6 to replace the measured sample. During the measurement, the α detector 7 and γ detector 8 work simultaneously, obtaining the α-ray and γ-ray energy spectrum information of the sample, qualitatively identifying the α and γ radionuclides in the sample, and quantitatively calculating the radioactivity of the sample. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the low-background α-γ energy spectrum composite measurement device described in Embodiment 1 of this utility model;

[0022] In the figure: 1. Lead shielding layer; 2. Lead shielding cover; 3. Pressure rod hinge; 4. Base; 5. Lifting motor; 6. Detector mounting bracket; 7. Alpha detector; 8. Gamma detector; 9. Pull-out sample stage. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the embodiments.

[0024] like Figure 1This invention provides a low-background α-γ energy spectrum composite measurement device with a reasonable structure, convenient use, good shielding, and capable of achieving combined α and γ energy spectrum measurements. The low-background α-γ energy spectrum composite measurement device includes a lead shielding layer 1, a lead shielding cover 2, a lever-type hinge 3, a base 4, a lifting motor 5, a detector mounting bracket 6, an α detector 7, a γ detector 8, and a pull-out sample stage 9. The lead shielding layer 1 is a hollow cylinder with a thickness of 12.1 cm, a copper surface, and a core filled with metallic lead. The lead shielding layer 1 is mounted on the base 4. The lead shielding cover 2 is 11.7 cm thick and is mounted on the lead shielding layer 1 via the lever-type hinge 3, allowing it to open and close by rotating horizontally. The lifting motor 5 includes a motor body and a lifting platform; the motor body is mounted on the base 4. The lifting platform, controlled by a motor, can be raised and lowered within the lead shielding layer 1. The detector mounting bracket 6 is fixedly mounted on the lifting platform of the lifting motor 5. The detector mounting bracket 6 has an α detector mounting slot, a pull-out sample stage slot, and a γ detector mounting slot in its upper, middle, and lower parts, respectively. The α detector 7 is mounted in the α detector mounting slot in the upper part of the detector mounting bracket 6, with its detection surface facing downwards. The γ detector 8 is mounted in the γ detector mounting slot in the lower part of the detector mounting bracket 6, with its detection surface facing upwards. The pull-out sample stage 9 is horizontally embedded in the pull-out sample stage slot in the middle layer of the detector mounting bracket 6. Support feet are provided below the base 4, connecting the base 4 to the ground. There are four support feet in total, with reinforcing ribs between each pair of adjacent feet. A connecting plate is provided between a pair of opposing reinforcing ribs to support and limit the lifting motor 5.

[0025] The three surfaces of the α detector 7, the γ detector 8, and the pull-out sample stage 9 are horizontally parallel and their center points are coaxial.

[0026] The α detector 7 and γ detector 8 face each other, and the distance between the pull-out sample stage 9 and the bottom detection surface of the α detector 7 is 1.0 cm, and the distance between the pull-out sample stage 9 and the top detection surface of the γ detector 8 is 8 cm.

[0027] The lifting motor 5, equipped with the detector mounting bracket 6, can move vertically inside the lead shielding layer 1, with a lifting distance range of 0 to 20 centimeters. When performing the lifting operation, the lead shielding cover 2 must be in the open state.

[0028] When the lifting motor 5 rises to its highest point, the horizontal height of the pull-out sample stage 9 is 3 cm higher than the upper surface of the lead shielding layer 1. The pull-out sample stage 9 can be pulled out from the slot of the detector fixing frame 6 for sample replacement.

Claims

1. A low-background alpha-gamma spectrometric combined measurement device, characterized in that, It comprises a lead shielding layer (1), a lead shielding cover (2), a base (4), a lifting motor (5), a detector fixing frame (6), an alpha detector (7), a gamma detector (8), and a pull-out sample table (9). The lead shielding layer (1) is a hollow cylinder and is made of metal lead. One end of the cylindrical surface of the lead shielding layer (1) is installed on the base (4), which is a plane and has a hole communicating with the cavity of the lead shielding layer (1).

2. The low-background alpha-gamma spectroscopy compound measurement device of claim 1, wherein, The lead shielding cover (2) is installed on the upper end cylindrical surface of the lead shielding layer (1) through an opening and closing mechanism and rotates in the horizontal direction to open and close.

3. The low-background alpha-gamma spectroscopy compound measurement device of claim 2, wherein, The lifting motor (5) comprises a motor body and a lifting platform.

4. The low-background alpha-gamma spectroscopy compound measurement device of claim 1, wherein, The motor body is installed below the base (4), and the lifting platform is connected to the motor body.

5. The low-background alpha-gamma spectroscopy compound measurement device of claim 4, wherein, The lifting platform is controlled by the motor body to vertically lift inside the cylindrical hollow cavity of the lead shielding layer (1).

6. The low-background alpha-gamma spectroscopy compound measurement device of claim 1, wherein, The detector fixing frame (6) is installed above the lifting platform of the lifting motor (5).

7. The low-background alpha-gamma spectroscopy compound measurement device of claim 1, wherein, The alpha detector mounting stop, the pull-out sample table slot, and the gamma detector mounting stop are arranged on the upper, middle, and lower parts of the detector fixing frame (6), respectively.

8. The low-background alpha-gamma spectroscopy compound measurement device of claim 1, wherein, The alpha detector (7) is installed at the alpha detector mounting stop on the upper part of the detector fixing frame (6) with the detection surface facing downward.

9. The low-background alpha-gamma spectroscopy compound measurement device of claim 8, wherein, The gamma detector (8) is installed at the gamma detector mounting stop on the lower part of the detector fixing frame (6) with the detection surface facing upward.

10. The low-background alpha-gamma spectroscopy compound measurement device of claim 9, wherein, The pull-out sample table (9) is horizontally embedded in the middle pull-out sample table slot of the detector fixing frame (6). The detection surface of the alpha detector (7), the detection surface of the gamma detector (8), and the three surfaces of the pull-out sample table (9) are horizontally parallel and coaxial at the center point. The distance between the bottom detection surface of the alpha detector (7) and the upper surface detection surface of the gamma detector (8) is not more than 3 cm. The lead shielding layer (1) is a hollow cylinder with a thickness of not less than 10 cm. The thickness of the lead shielding cover (2) is not less than 10 cm. The opening and closing mechanism is a press rod type hinge (3). The outer surface of the lead shielding layer (1) is wrapped with copper metal. The base (4) is provided with supporting legs below to connect the base (4) and the ground. There are four supporting legs, and reinforcing ribs are arranged between every two adjacent supporting legs. A connecting plate is arranged between one pair of opposite reinforcing ribs to support and limit the lifting motor (5).

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