A neutron irradiation sample box convenient for remote operation and a dismounting tool thereof

Abstract

The application discloses a neutron irradiation sample box convenient for remote operation and a dismounting tool thereof, and belongs to the cross field of nuclear science and technology application and equipment manufacturing. The sample box comprises a sample cover, a sealing sheet, a sample inner grid and a cavity. The sample cover is in threaded connection with the cavity. The sealing sheet is sealed by plastic deformation. The sample inner grid is divided into partition compartments for placing samples. The dismounting tool comprises an installation base, a screwing handle, a lower jaw, a circular arc knife edge, a sample box separation nut and an arched sample box positioning block and the like. The sample box is convenient for remote operation of adding and removing samples by special design. The non-welding sealing is adopted to guarantee sample irradiation conditions. The dismounting tool can be remotely operated in the whole process. The application further increases innovative features such as radiation-resistant adhesive, a pressure sensor and a fine adjustment device, improves sealing stability and operation accuracy, and solves the problems of inconvenience in remote operation, sealing and sample adding and removing of the traditional sample box.

Description

Technical Field

[0001] This invention belongs to the interdisciplinary field of nuclear science and technology application and equipment manufacturing, specifically relating to a neutron irradiation sample box and its disassembly and assembly fixture that is easy to operate remotely. The sample box is mainly used for neutron irradiation experiments on materials in high-radiation environments such as spallation neutron source target stations. Through innovative sealing structure and remote operation design, the sample box can be easily disassembled and the samples can be safely removed, solving the technical problems of traditional sample boxes in terms of remote operation disassembly, sealing performance and sample addition and subtraction. Background Technology

[0002] In the field of nuclear science and radioactive materials research, neutron irradiation experiments on materials are of paramount importance, as they directly relate to the safe operation of nuclear facilities and the selection and utilization of key materials for new devices. During the operation of facilities such as spallation neutron source target stations, a large number of high-energy particles, such as neutrons, are generated. These high-energy particles can activate structural materials (such as austenitic stainless steel) and release gamma rays. Therefore, in order to accurately assess the service life and performance changes of materials after irradiation, neutron irradiation experiments on materials must be conducted in a high-radiation environment.

[0003] Traditionally, neutron-irradiated samples are usually placed in fission reactors, where cooling water is often present. To avoid the corrosion and erosion effects of the cooling water on the irradiated samples, the sample boxes are usually sealed by welding. However, this welding sealing technology has many significant limitations.

[0004] On the one hand, welded and sealed sample boxes need to be cut to open after the experiment, which is not convenient for remote operation. In the actual operation of nuclear science research, due to the danger of the radiation environment, remote operation is an important means to ensure the safety of researchers, and traditional welded and sealed sample boxes cannot meet this requirement.

[0005] On the other hand, traditional sample boxes are manufactured as a single piece, making it impossible to add or remove samples or repeat irradiation. In actual scientific research experiments, it is often necessary to adjust the samples according to different experimental needs, such as increasing or decreasing the number of samples, or irradiating the same batch of samples multiple times to study performance changes under different irradiation times. The structure of traditional sample boxes limits the flexibility and diversity of experiments, increasing the limitations of experiments.

[0006] In addition, traditional welding sealing methods have a heat-affected zone, which can easily lead to changes in material properties and affect the accuracy of experimental results. Moreover, traditional irradiation sample boxes require cutting equipment to open, which is expensive and the collection and disposal of radioactive debris is difficult, increasing experimental costs and safety risks. Summary of the Invention

[0007] In response to the numerous problems existing in the aforementioned traditional technologies, the development of a neutron irradiation sample box and its assembly / disassembly fixture that can be effectively and conveniently disassembled and installed remotely, achieve good sealing, and enable repeated irradiation of samples has become a key issue that urgently needs to be addressed in the field of nuclear science and radioactive materials research.

[0008] The technical solution adopted in this invention is: a neutron irradiation sample box and its disassembly / assembly fixture that are easy to operate remotely, comprising:

[0009] The sample box includes: a sample cover, which is threaded to the cavity and has a boss with external threads on the top for gripping by a robotic arm;

[0010] The sealing sheet, placed between the sample cap and the cavity, is made of an elastic / plastic deformable material. When the sample cap is tightened, it undergoes plastic deformation due to the thread clamping force to achieve a seal.

[0011] The cavity is provided with an external threaded interface that mates with the sample cap, and the top edge has an annular blade structure to enhance the sealing effect. The bottom is provided with an internal threaded hole structure for connecting with the threaded boss of the sample cap.

[0012] The sample rack is placed inside the cavity and has multiple compartments for sample placement.

[0013] Sample box assembly / disassembly fixture, the sample box assembly / disassembly fixture comprising:

[0014] The mounting base is used to install and fix the disassembly and assembly tools and to place the sample boxes that need to be disassembled and assembled. It is equipped with a positioning groove for installing and positioning the arched sample box positioning block.

[0015] Tighten the handle, which is installed on the trapezoidal lead screws on both sides, to lengthen the lever arm and thus increase the torque, making operation easier;

[0016] The lower jaw, mounted on a trapezoidal lead screw on one side, is used to clamp the bottom of the sample box cavity;

[0017] The rounded blade is mounted on the upper jaw and is used to pry open the sealing plate of the sample box;

[0018] The sample box separation nut is placed on the sample cover to open the sample box.

[0019] The arched positioning block is installed on the positioning groove of the mounting base, precisely matching the shape of the sample box cavity bottom, ensuring stability and preventing slippage when force is applied.

[0020] The sealing sheet is made of a material with low induced radioactivity and a hardness lower than that of the sample box, such as pure aluminum.

[0021] The sample box is sealed using either a metal seal or a rubber seal. When a metal seal is used, it is made of a metal material with a low gas venting rate. Structurally, the annular blade structure at the bottom of the blade cavity has a 60°-80° bevel.

[0022] The sample boxes can be interconnected, making it easy to adjust, reduce, or increase the number of sample boxes.

[0023] The sample box material has a Rockwell hardness ≥70HRA and is made of a material with low induced radioactivity.

[0024] The roughness of the sealing surface of the sample box is ≤3.2 micrometers.

[0025] It also includes a hot chamber and an operating room, which are isolated by a shielding wall. The neutron irradiation sample box and its disassembly and assembly fixtures are located in the hot chamber, and the remote control system is located in the operating room.

[0026] The sample box assembly and disassembly fixture is operated using a master-slave robotic arm.

[0027] The threaded boss of the sample cover is connected end to end to the bottom of the cavity, which facilitates remote operation to add or remove sample boxes.

[0028] The mounting base secures the entire assembly and disassembly fixture and places the sample box to be assembled or disassembled in the designated position. The arched positioning block precisely matches the shape of the bottom of the sample box cavity, ensuring stability and preventing slippage when force is applied.

[0029] The beneficial effects of this invention are: the neutron irradiation sample box and its disassembly / assembly fixture, which are easy to operate remotely, have many significant advantages over traditional technologies.

[0030] Improved ease of remote operation: The top of the sample cover is designed with a boss featuring external threads, which is connected end to end to the bottom of the cavity, providing a gripping point for the robotic arm clamp. This facilitates the addition and removal of samples via remote operation, effectively solving the problem of traditional sample boxes being inconvenient for remote disassembly and installation. It greatly improves the convenience and safety of operation, and meets the experimental needs of high-radiation environments.

[0031] Optimized sealing performance: A non-welded sealing method is adopted, which utilizes the plastic deformation of the sealing plate under the pressure of the thread when the sample cap is tightened to achieve a seal. This sealing method can not only effectively prevent the influence of the external environment (such as oxidation) on the sample and provide better irradiation conditions for the sample, but also avoid the problem of material property changes caused by the heat-affected zone of welding, thus ensuring the accuracy of experimental results.

[0032] Sample re-irradiation is achieved: The split-type processing design allows for convenient addition and removal of samples from the sample box, breaking the limitations of traditional integrated sample boxes that cannot add, remove, or re-irradiate samples. This meets the needs of scientific research experiments for studying sample performance under different irradiation times, reduces experimental limitations, and improves experimental flexibility and diversity.

[0033] Improved experimental efficiency and safety: The design of the disassembly and assembly fixture enables remote operation of the entire sample box disassembly and assembly process. Using this fixture, the sample box can be opened quickly and safely and the sample can be removed. One set of fixtures can complete operations such as opening the lid, breaking the seal, separating the lid and sample box, and connecting them. It avoids the problem of difficult collection and disposal of radioactive debris generated by traditional cutting methods of opening sample boxes. While ensuring experimental efficiency, it greatly improves safety and reduces experimental costs and safety risks. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the assembly state of the sample box of the present invention;

[0035] Figure 2 This is an exploded structural diagram of the sample box tooling of the present invention;

[0036] Figure 3 This is a schematic diagram of the exploded state structure of the sample cover and cavity of the present invention;

[0037] Figure 4 This is a cross-sectional schematic diagram showing the disassembled state of the sample cover and cavity of the present invention.

[0038] Figure labeling: 1. Sample cover; 2. Sealing plate; 3. Sample inner grid; 4. Cavity; 41. Internal threaded hole structure; 42. Annular blade structure; 5a. Mounting base; 6. Tightening handle; 7. Handle; 8. Handle head; 9. T-nut; 10. Support block; 11. Sample box separation nut; 12a. Arched sample box positioning block. Detailed Implementation

[0039] The neutron irradiation sample box and its disassembly and assembly tooling of the present invention, which are easy to operate remotely, mainly include two parts: the sample box and the tooling for disassembly and assembly. The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0040] I. Sample Box Structure and Assembly

[0041] The sample box consists of a sample cover 1, a sealing sheet 2, an inner sample frame 3, and a cavity 4.

[0042] Cavity 4: As the main supporting structure of the sample box, it is equipped with an external threaded interface for threaded connection with the sample cover 1. The top edge of cavity 4 has an annular blade structure 42, which enhances the sealing effect during the sealing process. The bottom of cavity 4 is equipped with an internal threaded hole structure 41 for connection with the threaded boss on the top of the sample cover 1, achieving a stable structural connection of the sample box and facilitating overall operation of the sample box during remote operation.

[0043] Sample rack 3: Placed inside cavity 4, it has multiple partitioned compartments. In practical use, samples to be irradiated can be placed in different partitioned compartments according to different experimental needs, so as to achieve simultaneous irradiation or classified management of multiple samples.

[0044] Sealing sheet 2: Located between sample cover 1 and cavity 4. Sealing sheet 2 is made of an elastic / plastic deformable material, such as pure aluminum, which has low induced radioactivity and a hardness lower than that of the sample box. When sample cover 1 is tightened, sealing sheet 2 is subjected to the thread clamping force, resulting in plastic deformation, thereby tightly fitting with the annular blade structure 42 at the top edge of cavity 4, forming a reliable seal, effectively preventing the influence of the external environment (such as oxidation) on the sample, and providing good irradiation conditions for the sample.

[0045] Sample cover 1: It is connected to the cavity 4 by threads, and its top is designed with a boss with external threads. The boss is connected to the bottom of the cavity 4 end to end, providing a gripping point for the robotic arm clamp, which facilitates the addition and subtraction of sample boxes through remote operation, meeting the needs of remote operation in high radiation environments.

[0046] II. Sample Box Assembly / Disassembly Fixture Structure and Operation

[0047] The sample box assembly and disassembly fixture consists of components such as mounting base 5a, tightening handle 6, lower jaw, arc blade, sample box separation nut 11, and arched sample box positioning block 12a. It also includes auxiliary components such as handle 7, handle head 8, T-nut 9, and support block 10.

[0048] Mounting base 5a: Serves as the basic support component for the entire assembly / disassembly fixture, used to install and fix the fixture and place the sample box to be disassembled / assembled. Mounting base 5a is equipped with a positioning groove for mounting and positioning the arched sample box positioning block 12a, ensuring stable placement of the sample box during assembly / disassembly.

[0049] Arched sample box positioning block 12a: Installed on the positioning groove of the mounting base 5a, its shape precisely matches the bottom outline of the sample box cavity. During disassembly and assembly operations, the arched sample box positioning block 12a ensures that the sample box is stable and does not slip during the application of force, providing a stable foundation for subsequent disassembly and assembly operations.

[0050] Tightening handle 6: Installed on the trapezoidal lead screws on both sides. The torque is increased by lengthening the lever arm, making operation easier for the operator. Handle heads 8 are welded to both ends of the tightening handle 6 for easy gripping. In actual operation, the operator can adjust the position of relevant components and the clamping force by rotating the tightening handle 6.

[0051] Lower jaws: Mounted on a trapezoidal lead screw on one side, the lower jaws open and close via the lead screw to clamp the bottom of the sample box cavity. During clamping, the lower jaws fit tightly against the bottom of the sample box cavity, ensuring that the sample box will not shift during subsequent operations.

[0052] Arc-shaped cutting edge: Installed on the upper jaw, its cutting edge curvature matches the annular cutting edge structure 42 at the top of the cavity 4. When it is necessary to open the sample box, the arc-shaped cutting edge, under the action of related components, can accurately pry open the sealing plate 2 of the sample box, breaking the seal and preparing for sample removal.

[0053] Sample box release nut 11: When the sample box needs to be opened, it is placed on the sample cover 1. By rotating the sample box release nut 11, sufficient force can be generated to release the locking state of the sample cover 1, thereby easily opening the sample cover 1 and taking out the sample placed on the sample inner grid 3.

[0054] Other auxiliary components: Handles 7 are fixed on both sides below the sample box separating nut 11, facilitating gripping and rotational force application by the operator. T-nuts 9 are located at the U-shaped clamping block end near the trapezoidal screw 3, serving a connecting and fixing function. Support block 10 is located between the lower and upper jaws, providing support and stability for the entire jaw structure.

[0055] III. Overall Operation Process

[0056] During the neutron irradiation experiment, the sample inner grid 3 is first placed into the cavity 4, and the sample to be irradiated is placed in the corresponding compartment of the sample inner grid 3 according to the experimental requirements. Then, the sealing plate 2 is placed between the sample cover 1 and the cavity 4, and the sample cover 1 is tightened, so that the sealing plate 2 undergoes plastic deformation under the thread clamping force, thereby sealing the sample box.

[0057] After the experiment, when the sample needs to be removed, first fix the mounting base 5a, place the irradiated sample box in a suitable position on the mounting base 5a, and position and fix it using the arched sample box positioning block 12a. Next, operate the tightening handle 6 to adjust the position of the lower jaws so that it clamps the bottom of the sample box cavity. Then, use the arc-shaped cutting edge to pry open the sealing plate 2 of the sample box. After that, put the sample box separating nut 11 on the threaded boss on the top of the sample cover 1, rotate the sample box separating nut 11 to open the sample cover 1, and thus take out the sample from the sample inner grid 3.

[0058] Example: This example describes in detail the application process of a remotely operated neutron irradiation sample box and its disassembly and assembly tooling in actual neutron irradiation experiments.

[0059] S1. Sample box preparation before experiment

[0060] First, the sample holder 3 is carefully placed inside the cavity 4. The sample holder 3 has multiple compartments. In this experiment, to study the performance changes of different materials under neutron irradiation, three different metallic material samples are placed in three different compartments. The cavity 4 serves as the main structure of the sample box, with an internally threaded hole structure 41 at the bottom and an annular blade structure 42 at the top edge.

[0061] Next, the sealing sheet 2 is placed between the sample cover 1 and the cavity 4. The sealing sheet 2 is made of pure aluminum, which has the characteristics of low induced radioactivity and a hardness lower than that of the sample box. Then, the sample cover 1 and the cavity 4 are connected by threads. As the sample cover 1 is tightened, the sealing sheet 2 is subjected to the thread clamping force, resulting in plastic deformation. It fits tightly with the annular blade structure 42 on the top edge of the cavity 4, forming a reliable seal and effectively preventing the influence of the external environment on the sample. The top of the sample cover 1 is designed with a boss with external threads. This boss is connected end to end to the bottom of the cavity 4, providing a support point for subsequent remote operation.

[0062] To further improve the stability of the sample box during irradiation and the durability of the sealing effect, a special radiation-resistant adhesive is coated on the contact surface between the sealing sheet 2 and the sample cover 1 and the cavity 4. This adhesive can maintain good adhesion under neutron irradiation environment without affecting the plastic deformation of the sealing sheet 2 to achieve the sealing function, thus reducing the problem of loosening of the seal caused by irradiation.

[0063] S2, Sample box assembly / disassembly fixture operation

[0064] After the neutron irradiation experiment is completed, the sample needs to be removed from the sample box for analysis; at this time, the sample box disassembly and assembly tooling is used for the operation.

[0065] First, the mounting base 5a is firmly fixed on the operating table. The mounting base 5a serves as the basic support for the entire assembly and disassembly fixture and is equipped with a positioning groove. The irradiated sample box is placed in a suitable position on the mounting base 5a and positioned and fixed by the arched sample box positioning block 12a. The arched sample box positioning block 12a precisely matches the shape of the bottom of the sample box cavity to ensure that the sample box will not be displaced during subsequent operations.

[0066] Operate the tightening handle 6, which is installed on the trapezoidal lead screws on both sides. The torque is increased by lengthening the lever arm, making the operation more labor-saving. The tightening handle 6 has handle heads 8 welded to both ends for easy gripping by the operator. By rotating the tightening handle 6, the position of the lower jaw is adjusted. The lower jaw is installed on the trapezoidal lead screw on one side, so that it can accurately clamp the bottom of the sample box cavity.

[0067] In order to more accurately control the force used to pry open the sealing sheet 2 during the disassembly and assembly process and avoid unnecessary damage to the sample box, pressure sensors and fine-tuning devices are installed on the relevant linkage components of the lower jaw and the arc blade. The pressure sensor can monitor the applied force in real time, and the fine-tuning device can make precise adjustments to the prying force of the arc blade based on the feedback information from the pressure sensor. The arc blade is installed on the upper jaw, and its cutting edge curvature matches the annular blade structure 42 at the top of the cavity 4. The sealing sheet 2 of the sample box is gently pried open using the arc blade.

[0068] Next, the sample box separating nut 11 is put onto the threaded boss on the top of the sample cover 1; the sample box separating nut 11 has handles 7 fixed through both sides below it, which makes it easy for the operator to hold and apply rotational force; by rotating the sample box separating nut 11, the locking state of the sample cover 1 is released, thereby opening the sample cover 1 and taking out the three metal material samples placed on the sample inner grid 3.

[0069] In the structure of the disassembly and assembly tooling, a support block 10 is also provided, located between the lower jaw and the upper jaw, which plays the role of supporting and stabilizing the jaw structure; at the same time, the U-shaped clamping block end near the trapezoidal screw has a T-nut 9, which is used for connecting and fixing related components to ensure the structural stability of the entire disassembly and assembly tooling.

[0070] As can be seen from this embodiment, the neutron irradiation sample box and its disassembly and assembly fixture of the present invention, which are easy to operate remotely, can safely and efficiently complete the process of placing, irradiating and removing samples in neutron irradiation experiments, and has innovative technical features, effectively solving the problems existing in traditional technologies.

[0071] The above description is merely a specific embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A neutron irradiation sample box and its assembly / disassembly fixture that are easy to operate remotely, characterized in that, Includes sample boxes and sample box assembly / disassembly fixtures; The sample box includes: The sample cover (1) is threadedly connected to the cavity (4), and the top is provided with a boss with external thread features for gripping by the robotic arm clamp; The sealing sheet (2) is placed between the sample cover (1) and the cavity (4). It is made of elastic / plastic deformable material. When the sample cover (1) is tightened, it undergoes plastic deformation due to the screw pressure to achieve sealing. The cavity (4) is provided with an external threaded interface that mates with the sample cover (1), the top edge has an annular blade structure (42), and the bottom is provided with an internal threaded hole structure (41) for connecting with the threaded boss of the sample cover (1). The sample rack (3) is placed inside the cavity (4) and has multiple partitioned compartments for sample placement; The sample box assembly / disassembly fixture includes: Mounting base (5a) is used to install and fix the disassembly and assembly tooling and to place the sample box to be disassembled and assembled, and is provided with positioning groove; An arched sample box positioning block (12a) is installed on the positioning groove of the mounting base (5a). Its shape precisely matches the bottom shape of the sample box cavity, ensuring stability and preventing slippage when force is applied. Tighten the handle (6), which is installed on the trapezoidal lead screws on both sides, to lengthen the lever arm and increase the torque; The lower jaw is mounted on a trapezoidal lead screw on one side and is used to clamp the bottom of the sample box cavity; The arc-shaped cutting edge is installed on the upper jaw, and the curvature of the cutting edge matches the annular cutting edge structure (42) at the top of the cavity (4), which is used to pry open the sealing plate (2). The sample box separation nut (11) is placed on the sample cover (1) when the sample box is opened, and is used to unscrew the sample cover (1). The handle (7) is fixed through both sides below the sample box separation nut (11) and is used to hold and apply rotational force; A support block (10) is located between the lower jaw and the upper jaw and is used to support and stabilize the jaw structure. T-nut (9) is set at the end of the U-shaped clamp near the trapezoidal screw for connection and fixation.

2. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The sealing sheet (2) is made of pure aluminum material with low induced radioactivity and a hardness lower than that of the sample box.

3. The neutron irradiation sample box and its disassembly / assembly fixture for easy remote operation according to claim 1, characterized in that, The annular blade structure (42) has a 60°-80° bevel and is sealed with a low air venting rate metal seal.

4. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The sample boxes are connected end to end by a threaded boss and an internal threaded hole structure (41), which facilitates remote operation to add or remove sample boxes.

5. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The sample box material has a Rockwell hardness ≥70HRA and is a low-inducible radioactivity material; the sealing surface roughness is ≤3.2 micrometers.

6. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The contact surfaces of the sealing sheet (2) with the sample cover (1) and the cavity (4) are coated with radiation-resistant adhesive.

7. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The linkage between the lower jaw and the arc blade is equipped with a pressure sensor and a fine-tuning device to precisely control the force required to pry open the sealing plate (2).

8. The neutron irradiation sample box and its disassembly / assembly fixture for easy remote operation according to claim 1, characterized in that, It also includes a hot chamber and an operating room, which are separated by a shielding wall; the sample box and disassembly / assembly equipment are located in the hot chamber, and the remote control system is located in the operating room.

9. The neutron irradiation sample box and its assembly / disassembly fixture for easy remote operation according to claim 1, characterized in that, The disassembly and assembly tools are remotely operated using a master-slave robotic arm.

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