Welding Structure Fatigue Life Test Device and Method

Abstract

Welding structure fatigue life test device, including a vibration test bench and test specimens installed on the vibration test bench, is characterized in that: the test specimens have welding structures whose fatigue life needs to be detected, and there are multiple test positions on the vibration test bench for installing test specimens. The present invention can apply tensile and compressive dynamic loads or bending dynamic loads to the test specimens to detect the tensile and compressive load fatigue life or bending load fatigue life of the welding structures. There are multiple test positions on the vibration test bench that can synchronously install multiple test specimens to achieve synchronous detection of multiple test specimens. The test device has high versatility, and the test process is closer to the actual application conditions of the welding structures whose fatigue life needs to be detected, improving the reliability and effectiveness of the test detection. The present invention also provides a welding structure fatigue life test method.

Description

Technical Field

[0001] The present invention provides a welding structure fatigue life test device and method, belonging to the technical field of welding structure detection. Background Art

[0002] At present, there are mainly two types of methods for predicting the fatigue life of welded joints. One is the method based on the S-N curve and the fatigue cumulative damage theory, and the other is the method based on the fracture mechanics theory and the crack growth rate curve. In actual engineering applications and common fatigue life finite element simulation analysis tools, the S-N curve of the joint and the fatigue cumulative damage method are mostly used to predict the life of welded structures. Therefore, the acquisition of the S-N curve of welded joints is crucial for the life prediction of welded structures in construction machinery. Since the existing calculation specifications for the fatigue life of welded structures are not perfect, a large amount of test data is required for the research on the fatigue life of welded joints of actual products. Moreover, a large number of tests are also needed to obtain the S-N curve. Currently, only the S-N curves of some typical welded joints are provided in the main international welding standards. Although they have a certain degree of generality, they may not be applicable to the actual joints of specific products. Therefore, in response to the large number of test requirements in welding fatigue tests and practical problems of the S-N curve, this solution proposes a method for testing the fatigue life of welded structure joints and test specimens.

[0003] Disadvantages of the prior art:

[0004] 1. Different load conditions such as tensile load and bending load require different special test equipment, and it is impossible to complete two loading conditions on the same equipment simultaneously;

[0005] 2. The types of testable joints are relatively few;

[0006] 3. There are relatively high technical requirements for the fixtures of the test equipment;

[0007] 4. It is impossible to conduct a large number of tests simultaneously, and each time the specimen is replaced, the accuracy of the fixture and the instrument equipment needs to be rechecked;

[0008] 5. It is impossible to apply a bending moment to the welded joint under the actual operating conditions of the product, and the test load is still mainly tensile and compressive loads. Summary of the Invention

[0009] The welding structure fatigue life test device and method provided by the present invention can apply tensile-compressive dynamic loads or bending dynamic loads to test specimens to detect the tensile-compressive load fatigue life or bending load fatigue life of the welding structure. There are multiple test positions on the vibration test bench where multiple test specimens can be synchronously installed to achieve synchronous detection of multiple test specimens. The test device has high versatility and strong practicability, and the test process is closer to the actual application conditions of the welding structure whose fatigue life needs to be detected, improving the reliability and effectiveness of test detection.

[0010] To achieve the above object, the technical solution adopted by the present invention is:

[0011] A welding structure fatigue life test device, including a vibration test bench and test specimens installed on the vibration test bench, is characterized in that: the test specimens have a welding structure whose fatigue life needs to be detected, and there are multiple test positions on the vibration test bench for installing test specimens.

[0012] Preferably, the test specimen includes a mass block, a support connection plate and a base. The upper end of the support connection plate is welded to the mass block, and the lower end is welded to the base. The base is positioned at the test position. The welding structure whose fatigue life needs to be detected is the welding structure between the upper end of the support connection plate and the mass block, the welding structure between the lower end of the support connection plate and the base, or the welding structure in the support connection plate.

[0013] Preferably, the vibration test bench includes a test platform, a horizontal vibration power component for driving the test platform to vibrate horizontally, and a vertical vibration power component for driving the test platform to vibrate vertically. The side of the test platform is movably connected to the horizontal vibration power component, and the bottom surface of the test platform is movably connected to the vertical vibration power component.

[0014] Preferably, multiple test positions are arranged in an array on the test platform.

[0015] Preferably, the test position is composed of four threaded connection holes distributed in a square shape, and mounting holes corresponding to the threaded connection holes are provided on the base.

[0016] A welding structure fatigue life test method, using the above-mentioned welding structure fatigue life test device, is characterized in that: a welding structure whose fatigue life needs to be detected is set in the test specimen, and according to the actual application conditions of the welding structure whose fatigue life needs to be detected, the mass and height of the test specimen, and the vibration amplitude and direction of the vibration test bench are adjusted.

[0017] Preferably, adjusting the mass of the test specimen means adjusting the mass of the mass block, and adjusting the height of the test specimen means adjusting the height of the support connection plate.

[0018] The beneficial effects of the present invention:

[0019] 1. The fatigue life test device for the welded structure of the present invention has a welded structure whose fatigue life needs to be detected in the test specimen. The test specimen is installed on a vibration test bench, and the vibration test bench drives the test specimen to move to detect the welded structure whose fatigue life needs to be detected. Tensile-compressive dynamic loads or bending dynamic loads can be applied to the test specimen to detect the tensile-compressive load fatigue life or bending load fatigue life of the welded structure. There are multiple test positions on the vibration test bench that can synchronously install multiple test specimens to achieve synchronous detection of multiple test specimens. The test device has high versatility and strong practicability.

[0020] 2. The welded structure whose fatigue life needs to be detected is the welded structure between the mass block and the support connecting plate, the welded structure between the support connecting plate and the base, or the welded structure in the support connecting plate. Select its position on the test specimen according to the position of the welded structure whose fatigue life needs to be detected in the actual application working condition, and by adjusting the mass of the mass block and the height of the support connecting block, make the test process closer to the actual application working condition of the welded structure whose fatigue life needs to be detected, and improve the reliability and effectiveness of the test detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the fatigue life test device for the welded structure in the specific embodiment.

[0022] Figure 2 It is a schematic diagram of the test.

[0023] Figure 3 For Figure 2 The enlarged schematic diagram at position A in

[0024] Figure 4 It is another schematic diagram of the fatigue life test device for the welded structure.

[0025] Figure 5 It is a schematic diagram of the distribution of the test positions on the test platform. DETAILED DESCRIPTION OF THE INVENTION

[0026] The following will Figures 1 - 5 make a detailed description of the embodiments of the present invention.

[0027] The fatigue life test device for the welded structure includes a vibration test bench 1 and a test specimen 2 installed on the vibration test bench 1. It is characterized in that: the test specimen 2 has a welded structure 3 whose fatigue life needs to be detected, and there are multiple test positions 4 for installing test specimens on the vibration test bench.

[0028] For the above-mentioned welding structure fatigue life test device, the test specimen 2 has a welding structure 3 whose fatigue life needs to be detected. The test specimen 2 is installed on the vibration test bench 1, and the vibration test bench 1 drives the test specimen 2 to move to detect the welding structure 3 whose fatigue life needs to be detected. Dynamic tensile-compressive loads or bending dynamic loads can be applied to the test specimen to detect the tensile-compressive load fatigue life or bending load fatigue life of the welding structure 3. The vibration test bench 1 has multiple test positions 4 where multiple test specimens 2 can be installed synchronously to achieve synchronous detection of multiple test specimens 2. The test device has high versatility and strong practicability.

[0029] Among them, the test specimen 2 includes a mass block 21, a support connecting plate 22, and a base 23. The upper end of the support connecting plate 22 is welded to the mass block 21, and the lower end is welded to the base 23. The base 23 is positioned at the test position 4. The welding structure 3 whose fatigue life needs to be detected is the welding structure between the upper end of the support connecting plate 22 and the mass block 31, the welding structure between the lower end of the support connecting plate 22 and the base 23, or the welding structure in the support connecting plate 22. The welding structure in the support connecting plate 22 refers to the welding structure that forms the support connecting plate 22. For example, if two sub-plates are welded to form the support connecting plate 22, then the welding structure in the support connecting plate 22 refers to the welding structure between the two sub-plates, as Figures 2 - 3 shown.

[0030] Among them, the vibration test bench 1 includes a test platform 11, a horizontal vibration power member 12 that drives the test platform 11 to vibrate horizontally, and a vertical vibration power member 13 that drives the test platform 11 to vibrate vertically. The side of the test platform 11 is movably connected to the horizontal vibration power member 12, and the bottom surface of the test platform 11 is movably connected to the vertical vibration power member 13. The vertical vibration power member 13 drives the test platform 11 to vibrate vertically to apply tensile-compressive loads to the welding structure 3 and detect its tensile-compressive load fatigue life. The horizontal vibration power member 12 drives the test platform 11 to vibrate horizontally to apply bending loads to the welding structure 3 and detect its bending load fatigue life. The test platform 11 is movably connected to the horizontal vibration power member 12 and the vertical vibration power member 13 respectively to avoid interference of the vertical vibration power member 13 during horizontal vibration and interference of the horizontal vibration power member 12 during vertical vibration. It can also achieve synchronous loading of horizontal vibration and vertical vibration to apply vibration loads in different directions and amplitudes to the test specimen 2.

[0031] Among them, multiple test positions 4 are distributed in an array on the test platform 11. To achieve synchronous detection of multiple test specimens 2, the test device has high versatility and strong practicability.

[0032] Among them, the test position 4 is composed of four square-distributed threaded connection holes 41, and mounting holes 231 corresponding to the threaded connection holes are arranged on the base 23. By passing bolts through the mounting holes 231 and locking them in the threaded connection holes 41, the test specimen 2 can be positioned on the test platform. The installation and disassembly of the test position 4 are convenient and simple, and it is easy to adjust its position on the test platform 11.

[0033] For the welding structure fatigue life test method, the above-mentioned welding structure fatigue life test device is adopted, and it is characterized in that: a welding structure for detecting the fatigue life to be required is arranged in the test specimen. According to the actual application working conditions of the welding structure for detecting the fatigue life to be required, the mass and height of the test specimen 2, the vibration amplitude and direction of the vibration test table are adjusted. The position of the welding structure to be detected for fatigue life on the test specimen is selected according to its position in the actual application working conditions, and by adjusting the mass and height of the test specimen 2, the test process is made closer to the actual application working conditions of the welding structure 3, thereby improving the reliability and effectiveness of the test detection.

[0034] Among them, adjusting the mass of the test specimen 2 means adjusting the mass of the mass block 21, and adjusting the height of the test specimen 2 means adjusting the height of the support connection plate 22. By adjusting the mass of the mass block 21 and the height of the support connection block 22, the test process is made closer to the actual application working conditions of the welding structure 3. The vibration amplitude and direction of the test table are adjusted by the horizontal vibration power member 12 and the vertical vibration power member 13 to make them the same as the load direction and amplitude in the actual application working conditions.

[0035] The technical solutions of the embodiments of the present invention are completely described above in conjunction with the accompanying drawings. It should be noted that the described embodiments are only a part of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making creative efforts belong to the scope of protection of the present invention.

Claims

1. Welding structure fatigue life test method, using a welding structure fatigue life test device, The welding structure fatigue life test device includes a vibration test table and a test specimen installed on the vibration test table. The test specimen has a welding structure whose fatigue life needs to be detected, and there are multiple test positions on the vibration test table for installing the test specimen; The test specimen includes a mass block, a support connecting plate and a base. The upper end of the support connecting plate is welded to the mass block, and the lower end is welded to the base. The base is positioned at the test position. The welding structures whose fatigue life needs to be detected are the welding structure between the upper end of the support connecting plate and the mass block, the welding structure between the lower end of the support connecting plate and the base, or the welding structure in the support connecting plate; It is characterized in that: A welding structure whose fatigue life needs to be detected is set in the test specimen, and according to the actual application working conditions of the welding structure whose fatigue life needs to be detected, the mass and height of the test specimen, and the vibration amplitude and direction of the vibration test table are adjusted; Adjusting the mass of the test specimen means adjusting the mass of the mass block, and adjusting the height of the test specimen means adjusting the height of the support connecting plate.

2. The welding structure fatigue life test method according to claim 1, It is characterized in that: The vibration test table includes a test platform, a horizontal vibration power member for driving the test platform to vibrate horizontally, and a vertical vibration power member for driving the test platform to vibrate vertically. The side surface of the test platform is movably connected to the horizontal vibration power member, and the bottom surface of the test platform is movably connected to the vertical vibration power member.

3. The welding structure fatigue life test method according to claim 2, It is characterized in that: A plurality of test positions are arranged in an array on the test platform.

4. The welding structure fatigue life test method according to claim 3, It is characterized in that: The test position is composed of four square-distributed threaded connection holes, and mounting holes corresponding to the threaded connection holes are provided on the base.

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