Helium filling pressure detection device for fuel rod

Abstract

The utility model belongs to the technical field of machinery, and particularly relates to a helium filling pressure detection device for a fuel rod, which is characterized in that a pressure gauge is connected with a specially-made rod through a gauge joint seat, and the specially-made rod comprises a specially-made lower end plug, a core block, a cladding tube and a spring, a fuel rod lower end plug structure is still adopted at the other end to simulate a normal welding structure, a specially-made lower end plug is connected with a cladding tube, a core block and a spring are arranged in the cladding tube, and an upper end plug is connected with the cladding tube. The problem that the helium filling pressure setting accuracy of the welding equipment cannot be directly determined is solved. The problem that the helium filling pressure detection accuracy of the welding equipment cannot be directly determined is solved. And the helium filling pressure of the welding equipment can be quickly determined to meet the fuel rod manufacturing requirements.

Description

Technical Field

[0001] The utility model belongs to the field of mechanical technology, and particularly relates to a fuel rod helium filling pressure detection device, which detects the helium filling pressure value of welding equipment and determines the reliability of the helium filling of the welding equipment through the detection result. Background Art

[0002] Fuel rods are core components in nuclear power plants. During their manufacturing process, they must be filled with helium at a certain pressure. This constant helium pressure within the fuel rods is crucial for ensuring the safe, stable, and reliable operation of the nuclear power plant. Due to the lack of dedicated non-destructive testing equipment for measuring helium pressure, the helium pressure within the fuel rods after manufacture is guaranteed by the welding equipment and process. During process testing, the fuel rods are subjected to destructive tests such as puncture to directly measure the helium pressure. While the helium pressure can be set and tested on the welding equipment, it is necessary to monitor it to avoid deviations due to inaccurate testing. Therefore, a fuel rod helium pressure detection device has been designed. Utility Model Content

[0003] The purpose of the utility model is to provide a fuel rod helium filling pressure detection device to solve the problem that the accuracy of the helium filling pressure setting of the welding equipment cannot be directly determined; solve the problem that the accuracy of the helium filling pressure detection of the welding equipment cannot be directly determined; and quickly determine that the helium filling pressure of the welding equipment meets the fuel rod manufacturing requirements.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present utility model is:

[0005] A fuel rod helium filling pressure detection device, wherein a pressure gauge is connected to a special rod via a gauge joint seat. The special rod comprises a special lower end plug, a pellet, a cladding tube, and a spring. One end of the special lower end plug is formed into a threaded structure for connection to the gauge joint seat, while the other end still uses the fuel rod lower end plug structure to simulate a normal welding structure. The special lower end plug is connected to the cladding tube, into which the pellet and spring are loaded, and the upper end plug is connected to the cladding tube.

[0006] The pressure gauge is connected to the gauge joint seat through a bolt structure.

[0007] Add sealing tape to the threaded section.

[0008] There is a through hole in the middle of the meter connector seat.

[0009] The sealing ring is installed in the gauge joint seat.

[0010] The specially made lower end plug is connected to the cladding tube by welding.

[0011] The cladding tube, the core block and the spring are all clearance fit.

[0012] The upper end plug is connected to the cladding tube by welding.

[0013] The beneficial effects achieved by the utility model are:

[0014] (1) Rapidly detect the helium pressure value of welding equipment, which is 50 times more efficient than the original manual removal of the welding equipment pressure gauge for inspection;

[0015] (2) Direct measurement with a pressure gauge makes the measurement more accurate and reliable;

[0016] (3) Reliable to use and easy to assemble and disassemble;

[0017] (4) Stronger compatibility: It only needs to make special rods according to the different fuel rod shapes and structures, which can be compatible with different types of fuel rods and meet different helium pressure requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a front view of a fuel rod helium filling pressure detection device;

[0019] Figure 2 A top view of a fuel rod helium filling pressure detection device;

[0020] In the figure: 1. Pressure gauge; 2. Gauge connector seat; 3. Sealing ring; 4. Special lower end plug; 5. Core block; 6. Cladding tube; 7. Spring; 8. Upper end plug. DETAILED DESCRIPTION

[0021] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] Pressure gauge 1 is used to directly measure internal helium pressure. Since pressure gauge 1 is connected to a gauge connector 2 and a custom rod, and the gauge connector 2 has a through-hole, the custom rod's custom lower end plug 4 and upper end plug 6 are not sealed. Therefore, when the entire assembly is inserted into the welding equipment with the upper end plug 8 for helium filling, helium enters the custom rod through the hole in the upper end plug 8 and then enters the pressure gauge through the through-hole in the custom lower end plug 4, ultimately providing the helium pressure reading. Pressure gauge 1 is assembled and disassembled according to the calibration cycle. To ensure a leak-proof seal, sealing tape is applied to the threaded section of the pressure gauge during installation to prevent leakage. Gauge connector 2 connects pressure gauge 1 to the custom rod. Pressure gauge 1 is bolted to gauge connector 2. A sealing ring 3 seals the custom lower end plug 4. To prevent leakage, the sealing ring 3 expands and deforms after being compressed, preventing leakage between the custom lower end plug 4 and gauge connector 2, which could affect the accuracy of the test results. The sealing ring 3 is installed in gauge connector 2. The sealing ring 3 bears the pressure of the special lower end plug 4 and the support force of the gauge joint seat 2. The special lower end plug 4, the core block 5, the cladding tube 6, and the spring 7 are collectively referred to as the special rod. Except for the special lower end plug 4, the special rod is made according to the structural and external characteristics of the fuel rod to reduce detection errors. One end of the special lower end plug 4 is made into a threaded structure, which is mainly used to connect to the gauge joint seat 2, while the other end still uses the fuel rod lower end plug structure to simulate the structure of a normal weld. The special lower end plug 4 is connected to the gauge joint seat 2 through a threaded structure, and the special lower end plug 4 is connected to the cladding tube 6 by welding. The core block 5 is installed in the cladding tube 6 and is subjected to the compression force of the spring 7. The core block 5 and the spring 7 are installed in the cladding tube 6, and are clearance-fitted with the core block 5 and the spring 7. The upper end plug 8 is connected to the cladding tube 6 by welding.

[0023] The pressure gauge 1 is bolted to the gauge connector seat 2. A sealing ring is installed in the gauge connector seat 2. The sealing ring 3 withstands the pressure from the specially designed lower end plug 4 and the supporting force of the gauge connector seat 2. The specially designed lower end plug 4 is threadedly connected to the gauge connector seat 2 and welded to the cladding tube 6. The core block 5 is installed in the cladding tube 6 and is compressed by a spring 7. The core block 5 and spring 7 are installed in the cladding tube 6, with a clearance fit between the core block 5 and spring 7. The upper end plug 8 is welded to the cladding tube 6.

[0024] During the process of welding fuel rods using welding equipment, it is necessary to set the pressure value of the helium filling and also to detect the filling pressure. However, since both are built into the welding equipment, in order to ensure its reliability, this device is specially designed to determine whether the set value and detection value of the welding equipment are consistent with this device. If there is a large deviation or exceeds the specified value, the welding equipment needs to be readjusted to ensure that the internal helium pressure value of the fuel rod manufactured using the welding equipment meets the requirements.

[0025] This device has a simple structure and is quick to assemble and disassemble. It consists of three parts: the first part is the pressure gauge, which can be disassembled for regular metrological calibration; the second part is the gauge joint seat with a sealing ring, which is mainly used to connect the pressure gauge and the special rod; the third part is the special rod, which is a pipe used on site, with one end specially made for connection to the gauge joint seat.

[0026] This device is designed to detect whether welding equipment is charging at the required pressure. It quickly determines whether the helium filling level in welding equipment meets the required level. This device uses a direct connection method, connecting a pressure gauge to a gauge connector and a special rod. When helium is introduced into one end of the rod, the pressure value is quickly obtained. Furthermore, due to the direct connection, the measurement results are reliable and accurately reflect the helium pressure within the rod.

[0027] This utility model is specially developed for the axial transport of fuel rods, but is also applicable to fuel rods, guide tubes, or other products with similar dimensions and structures. It can quickly detect the set pressure of welding equipment and whether the pressure is consistent with the actual parameters.

Claims

1. A fuel rod helium filling pressure detection device, characterized by: The pressure gauge is connected to a special rod through a gauge joint seat. The special rod includes a special lower end plug, a pellet, a cladding tube, and a spring. One end of the special lower end plug is made into a threaded structure for connection to the gauge joint seat, and the other end still uses the fuel rod lower end plug structure to simulate a normal welding structure. The special lower end plug is connected to the cladding tube, and the pellet and spring are loaded into the cladding tube. The upper end plug is connected to the cladding tube.

2. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: The pressure gauge is connected to the gauge joint seat through a bolt structure.

3. The fuel rod helium filling pressure detection device according to claim 2, characterized in that: Add sealing tape to the threaded section.

4. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: There is a through hole in the middle of the meter connector seat.

5. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: The sealing ring is installed in the gauge joint seat.

6. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: The specially made lower end plug is connected to the cladding tube by welding.

7. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: The cladding tube, the core block and the spring are all clearance fit.

8. The fuel rod helium filling pressure detection device according to claim 1, characterized in that: The upper end plug is connected to the cladding tube by welding.

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