Tool and device for testing stress and strain around plate connecting hole

Abstract

The utility model belongs to the field of sheet material strain test, and particularly relates to a sheet material connecting hole periphery stress strain test tool and device, which comprises a base, a groove arranged on the base, a mounting hole transversely penetrating through the groove, a fastener detachably arranged in the mounting hole, and a strain sensor used for detecting sheet material sample strain, the strain sensor is arranged around the connecting hole of the plate sample, during testing, the fastener penetrates through the connecting hole of the plate sample to fix the plate sample in the groove, and the strain sensor can detect the magnitude of stress strain around the connecting hole; compared with the stress which can be borne by the periphery of the plate connecting hole in the actual use scene, the plate with the thickness and the strength meeting the requirements is tested, the problems that the thickness of the plate is large, and high-strength steel is excessively used are solved, and the raw material cost is reduced.

Description

Technical Field

[0001] The utility model belongs to the field of sheet metal strain tests, and particularly relates to a stress and strain test tooling and device around a connecting hole of a sheet metal. Background Art

[0002] In a structure where metal sheets are connected by fasteners such as bolts, the material and thickness of the metal sheets will affect the stress that the area around the connecting hole can withstand. Based on actual requirements and cost control considerations, it is necessary to select a suitable sheet material and thickness. Then, stress and strain tests need to be performed on different sheets.

[0003] When the connecting hole of the metal sheet is supported by relevant fasteners, there are large stresses and strains in the area near the fastener (i.e., around the connecting hole). The existing test device applies tensile force to both ends of the sheet through a universal material testing machine. Although it can detect the mechanical strength of different sheets, it cannot reflect the stress and strain around the connecting hole of the sheet, and thus cannot accurately select a suitable sheet. To meet actual needs, the thickness of the sheet is often large or high-strength steel is overused, resulting in high raw material costs. Summary of the Utility Model

[0004] The technical problem to be solved by the utility model is to provide a stress and strain test tooling and device around a connecting hole of a sheet metal, which can reflect the stress and strain around the connecting hole of the sheet metal and can more accurately select a suitable sheet.

[0005] The utility model provides a stress and strain test tooling around a connecting hole of a sheet metal, including a base. A groove, an installation hole horizontally penetrating the groove, a fastener detachably arranged in the installation hole, and a strain sensor for detecting the strain of a sheet metal specimen are provided on the base. The strain sensor is arranged around the connecting hole of the sheet metal specimen. During the test, the fastener passes through the connecting hole of the sheet metal specimen to fix the sheet metal specimen in the groove.

[0006] Optionally, the installation hole is a through hole horizontally penetrating the base, and the fastener includes a bolt and a nut.

[0007] Optionally, the bolt is a hexagon head bolt or a double-headed bolt.

[0008] Optionally, the base is provided with a relief slot hole extending to the groove for the strain sensor to pass through during installation and disassembly.

[0009] Optionally, relief slot holes are arranged on both sides of the groove.

[0010] Optionally, the relief slot hole is located above the installation hole.

[0011] Optionally, the groove is a rectangular through groove.

[0012] Optionally, the width of the groove is 3 - 20 mm, the depth is 50 - 150 mm, and the length is 50 - 300 mm.

[0013] Optionally, the stress and strain test tooling around the plate connection hole further includes two sleeves, which are arranged in the mounting holes and located on both sides of the groove respectively. The fastener passes through the two sleeves, and the inner and outer walls of the sleeves are respectively in contact with the fastener and the inner wall of the mounting hole.

[0014] The beneficial effect of the present utility model is that the plate specimen is placed in the groove and fixed by the fastener, and the strain sensor is arranged around the connection hole of the plate specimen, that is, at the stress concentration area of the plate. When a tensile force or a pressure is applied to the part of the plate specimen protruding from the groove, the connection hole is subjected to the reaction force of the fastener, and the strain sensor can detect the stress and strain magnitude around the connection hole. By testing plates with different materials and thicknesses and comparing with the stress that the plate connection hole needs to withstand in the actual use scenario, plates with suitable thickness and strength can be tested, avoiding the problems of large plate thickness and excessive use of high-strength steel, and reducing the raw material cost.

[0015] The present utility model provides a stress and strain test device around a plate connection hole, including the stress and strain test tooling, a universal material testing machine, and a strain analyzer electrically connected to the strain sensor. The stress and strain test tooling is installed on the universal material testing machine, and the universal material testing machine is used to apply a force to the plate specimen. The plate specimen is installed on the stress and strain test tooling, and the actual test data of the strain sensor is analyzed by the strain analyzer to test and analyze the actual stress and strain magnitudes of the plate specimen near the bolt force, so as to more accurately select a suitable plate. Description of the Drawings

[0016] Figure 1 is a three-dimensional structural schematic diagram of the stress and strain test tooling of the present utility model;

[0017] Figure 2 is a front view of the stress and strain test tooling of the present utility model;

[0018] Figure 3 is Figure 2 the sectional view taken along line A - A in

[0019] Figure 4 is Figure 2 the sectional view taken along line A - A in

[0020] Figure 5 is Figure 4 the enlarged view of area B in

[0021] In the figure: 10, base; 101, groove; 102, mounting hole; 103, relief slot hole; 104, fixing hole; 20, fastener; 201, bolt; 202, nut; 203, sleeve; 204, annular gasket; 30, strain sensor; 301, connecting wire; 40, sheet specimen. Specific implementation mode

[0022] As Figures 1 - 3 shown, a stress and strain test tooling around the connecting hole of a sheet provided by the present utility model includes a base 10. A groove 101, a mounting hole 102 horizontally penetrating the groove 101, a fastener 20 detachably arranged in the mounting hole 102, and a strain sensor 30 for detecting the strain of the sheet specimen 40 are provided on the base 10. The strain sensor 30 is arranged around the connecting hole of the sheet specimen 40. During the test, the fastener 20 passes through the connecting hole of the sheet specimen 40 to fix the sheet specimen 40 in the groove 101.

[0023] Compared with the prior art, for the stress and strain test tooling around the connecting hole of the sheet provided by the present utility model, the sheet specimen 40 is placed in the groove 101 and fixed by the fastener 20. The strain sensor 30 is arranged around the connecting hole of the sheet specimen 40, that is, at the stress concentration area of the sheet. When a tensile or compressive force is applied to the part of the sheet specimen 40 protruding from the groove 101, the connecting hole is subjected to the reaction force of the fastener 20. The strain sensor 30 can detect the stress and strain magnitude around the connecting hole. By testing sheets of different materials and thicknesses and comparing with the stress that the connecting hole of the sheet needs to withstand in the actual use scenario, sheets with the required thickness and strength can be tested, avoiding the problems of large sheet thickness and excessive use of high-strength steel, and reducing the raw material cost.

[0024] In one embodiment, please refer to Figure 3 , the mounting hole 102 is a through hole horizontally penetrating the base 10, and the fastener 20 includes a bolt 201 and a nut 202. During use, the bolt 201 penetrates into the mounting hole 102 from one end and passes through the connecting hole of the sheet specimen 40, extending out from the other end. Then, the nut 202 is screwed with the bolt 201. When the mounting hole 102 can be a round hole and the bolt 201 is a hexagonal head bolt 201, the extending end of the bolt 201 is connected to the nut 202. Or when the bolt 201 is a double-headed bolt 201, the two ends of the bolt 201 are respectively screwed with the nut 202.

[0025] It should be noted that the base 10 is made of steel, and the overall shape is rectangular. The groove 101 is located in the middle of the base 10. The aperture of the mounting hole 102 is larger than the diameter of the bolt 201, so as to be adapted to different specifications of bolts 201. During the test, the working conditions of fixing test specimens (different types of sheets) with different specifications of screws, bolts, etc. can be simulated.

[0026] In another embodiment, the mounting holes 102 are respectively a round hole and a threaded hole on both sides of the groove 101. One end of the bolt 201 is screwed into the threaded hole. If the bolt 201 is a double-headed bolt, the other end is screwed to the nut 202. If the bolt 201 is a hexagon head bolt, the bolt 201 is tightened by rotating the hexagon head.

[0027] In one implementation, please refer to Figure 1 and Figure 2 The base 10 is provided with a relief slot hole 103 that extends to the groove 101 for the strain sensor 30 to pass through during installation and removal. The relief slot hole 103 is close to the mounting hole 102, so as to ensure that the strain sensor 30 is as close as possible to the fastener 20 and there is more structure of the base 10 above the relief slot hole 103 to ensure that the base 10 has sufficient structural strength. At the same time, the relief slot hole 103 can be designed below and / or above the mounting hole 102 to have more options for installing the strain sensor 30. Specifically, after the plate specimen 40 is fixed on the base 10, the strain sensor 30 is pasted on the surface of the plate specimen 40 through the relief slot hole 103. The connecting wire 301 of the strain sensor 30 passes through the relief slot hole 103 instead of passing between the groove 101 and the plate specimen 40, which can avoid the connecting wire 301 being squeezed and enable the groove 101 of the same width to test a thicker plate specimen 40.

[0028] In one embodiment, relief slot holes 103 are provided on both sides of the groove 101. In this way, strain sensors 30 can be pasted on both sides of the plate specimen 40, further ensuring the accuracy of the test.

[0029] In one embodiment, the groove 101 is a rectangular through groove, where the width of the groove 101 is 3 - 20 mm, the depth is 50 - 150 mm, and the length is 50 - 300 mm.

[0030] In another embodiment, please refer to Figure 4 and Figure 5 For the stress and strain test tooling around the plate connection hole, it further includes two sleeves 203, which are arranged in the mounting holes 102 and are located on both sides of the groove 101 respectively. The fastener 20 passes through the two sleeves 203, and the inner and outer walls of the sleeves 203 are respectively in contact with the fastener 20 and the inner wall of the mounting hole 102. In this way, when bolts 201 of different specifications are used, sleeves with different wall thicknesses need to be matched, and the inner and outer walls of the sleeves 203 can be respectively in contact with the fastener 20 and the inner wall of the mounting hole 102 to prevent the fastener 20 from shifting.

[0031] Furthermore, an integrally formed annular gasket 204 is provided at one end of the sleeve 203 to facilitate the installation and removal of the sleeve 203.

[0032] The utility model provides a stress and strain test device around a connecting hole of a plate, which comprises a stress and strain test tooling, a universal material testing machine and a strain analyzer electrically connected to a strain sensor 30. The stress and strain test tooling is positioned and installed on the universal material testing machine through two fixing holes 104 opened at the bottom, and the universal material testing machine is used to apply a force to a plate specimen 40. The plate specimen 40 is installed on the stress and strain test tooling, and the actual test data of the strain sensor 30 is analyzed by the strain analyzer to test and analyze the actual stress and strain magnitudes of the plate specimen 40 near the stressed bolt 20, so that a suitable plate can be selected more accurately.

[0033] Those of ordinary skill in the art should understand that any discussion of the above embodiments is exemplary only and is not intended to imply that the scope of the present application is limited to these examples; under the concept of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations in different aspects of one or more embodiments of the present application as described above, which are not provided in detail for the sake of brevity.

[0034] One or more embodiments of the present application are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the present application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of one or more embodiments of the present application shall be included within the protection scope of the present application.

Claims

1. A stress-strain test tool around a plate connection hole, characterized in that: The invention comprises a base (10), the base (10) being provided with a groove (101), a mounting hole (102) extending transversely through the groove (101), a fastener (20) detachably arranged in the mounting hole (102), and a strain sensor (30) for detecting the strain of a plate sample (40), the strain sensor (30) being arranged around a connecting hole of the plate sample (40), and during a test, the fastener (20) passes through the connecting hole of the plate sample (40) to fix the plate sample (40) in the groove (101).

2. The stress-strain test tool around the plate connection hole according to claim 1, characterized in that: The mounting hole (102) is a through hole that passes through the base (10) transversely, and the fastener (20) comprises a bolt (201) and a nut (202).

3. The stress-strain test tool around the plate connection hole according to claim 2, characterized in that: The bolt (201) is a hexagonal head bolt (201) or a stud bolt (201).

4. The stress-strain test tool around the plate connection hole according to claim 1, characterized in that: The base (10) is provided with a clearance slot (103) extending to the groove (101) for the strain sensor (30) to pass through during installation and removal.

5. The stress-strain test tool around the plate connection hole according to claim 4, characterized in that: Both sides of the groove (101) are provided with clearance slots (103).

6. The stress-strain test tool around the plate connection hole according to claim 4, characterized in that: The clearance slot (103) is located above the mounting hole (102).

7. The stress-strain test tool around the plate connection hole according to any one of claims 1 to 6, characterized in that: The groove (101) is a rectangular through groove.

8. The stress-strain test tool around the plate connection hole according to claim 7, characterized in that: The groove (101) has a width of 3-20 mm, a depth of 50-150 mm, and a length of 50-300 mm.

9. The stress-strain test tool around the plate connection hole according to any one of claims 1 to 6, characterized in that: It also includes two sleeves (203) which are arranged in the mounting hole (102) and are respectively located on both sides of the groove (101); the fasteners (20) are inserted through the two sleeves (203); and the inner and outer walls of the sleeves (203) are respectively fitted with the fasteners (20) and the inner wall of the mounting hole (102).

10. A stress-strain test device around a plate connection hole, characterized in that: It comprises the stress-strain test tooling as claimed in claim 1, a universal material testing machine and a strain analyzer electrically connected to the strain sensor (30), wherein the stress-strain test tooling is installed on the universal material testing machine, and the universal material testing machine is used to apply a force to a plate sample (40).

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