CN213053682U

CN213053682U - Precision drilling device for testing residual stress of large workpiece

Info

Publication number: CN213053682U
Application number: CN202021370454.5U
Authority: CN
Inventors: 袁武华; 马雪鹤
Original assignee: Hunan University
Current assignee: Hunan University
Priority date: 2020-07-13
Filing date: 2020-07-13
Publication date: 2021-04-27
Anticipated expiration: 2030-07-13

Abstract

A precision drilling device for testing residual stress of a large workpiece comprises an XYZ three-axis moving platform, wherein a drilling machine and a high-definition camera are fixed on a moving end of the XYZ three-axis moving platform, a drill bit of the drilling machine faces a test workpiece, a lens of the high-definition camera faces a drill bit drilling end, and the high-definition camera is connected with an observation screen in a wireless or wired mode. The device is suitable for rolled plates or forgings with the width of 1-5 meters and the large size in the length direction, and overcomes the defect that a large-size sample cannot be accurately tested in the prior art.

Description

Precision drilling device for testing residual stress of large workpiece

Technical Field

The utility model relates to a test large-scale work piece residual stress's accurate drilling equipment.

Background

The residual stress refers to the stress which is remained in the component and maintains a self-balancing state under the condition that the component is not subjected to any external load. In the processes of welding, forging and forming, heat treatment, machining, assembling and the like of the material, the material generates uneven plastic deformation to form volume stress due to the uneven action of external machinery and heat, and generates structural stress due to the uneven action of microstructures, in-crystal substructures and the like caused by material phase change and precipitation, and the two interact to form complex residual stress field distribution in the component.

As a basis for residual stress research and control, residual stress testing techniques have been continuously emerging and perfected in recent years. The existing residual stress testing technology can be divided into a nondestructive testing method and a destructive testing method, wherein the destructive testing method is to apply external mechanical load to destroy the integrity of a workpiece, so that the workpiece is locally deformed, and the residual stress is reversely deduced based on the elastic-plastic mechanical principle. The drilling method is a mode of a destructive detection method, is relatively simple and rapid, is one of the most commonly used destructive detection methods for evaluating residual stress, has the advantages of high accuracy, good reliability and the like, and can generally repair a small drilled hole due to damage to a sample. The principle is to introduce a small hole (about 1.5mm in diameter and about 2.0 mm deep) at the location where the residual stress is to be measured, drill a hole to relieve the residual stress, and calculate the residual stress using a strain gage of a particular type and a suitable analysis program.

In current drilling method equipment, fixed tripod in test point top usually, tripod center fretwork hole to this with microscope centering and handheld electric drill drilling, during drilling, handheld electric drill precision itself is relatively poor, often takes place vibrations and angle slope when drilling, influences measuring result. When testing the residual stress at the center of the large-sized workpiece, a tester needs to tread near the workpiece test point to perform measurement, and deformation is generated at the drilling point and the periphery of the drilling point, so that the difference between the test result and the actual residual stress value is large.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming prior art not enough and providing a degree of automation height, error little, during the test the tester need not with the work piece contact, the high accurate drilling equipment of the large-scale work piece residual stress of test of measuring accuracy, the device is applicable to the width at 1 ~ 5 meters, the great rolling panel or the forging of length direction size.

The utility model adopts the following implementation scheme:

a precision drilling device for testing residual stress of a large workpiece comprises an XYZ three-axis moving platform, wherein a drilling machine 7 and a high-definition camera 6 are fixed on a moving end of the XYZ three-axis moving platform, a drill bit 8 of the drilling machine 7 faces a test workpiece 9, a lens of the high-definition camera 6 faces a drill bit drilling end, and the high-definition camera 6 is connected with an observation screen in a wireless or wired mode. Adopt above-mentioned structure, fine setting XYZ triaxial moving platform, make the drill bit aim at the foil gage center on the test workpiece, make the drill bit contact with foil gage center on the test workpiece, zero clearing the strain gauge data, start the rig, drill the test workpiece, in whole adjustment process, can very clearly observe the relation of drill bit and drilling position through observing the observation screen of being connected with high definition digtal camera, thereby to guaranteeing the accuracy of drilling position, drive rig vertical migration drilling through XYZ triaxial moving platform, need not to trample the test workpiece, prevent that the test workpiece from producing deformation, and lock through other diaxons to XYZ triaxial moving platform before creeping into, guarantee the stability of creeping into, thereby guarantee the accuracy of follow-up residual stress test.

In this embodiment, the high-definition camera 6 is mounted on the moving end of the XYZ three-axis movement platform by an adjustment bracket 5.

In this embodiment, the adjusting bracket 5 is composed of three sections of connecting rods, and the connecting rods are connected with each other through a spherical hinge capable of locking the angle.

In this embodiment, the XYZ three-axis movement platform includes a support frame 10, an X-axis movement stage 1, a Y-axis movement stage 2, and a Z-axis movement stage 3, the support frame 10 is disposed over the test workpiece 9, the X-axis movement stage 1 is mounted on the support frame 10, the Y-axis movement stage 2 is mounted on the X-axis movement stage 1, the Z-axis movement stage 3 is mounted on the Y-axis movement stage 2, and the drilling machine 7 and the high-definition camera 6 are both mounted on the Z-axis movement stage 3.

In this embodiment, the bottom of the supporting leg of the supporting bracket 10 is provided with a pulley 4, and the pulley 4 is a universal pulley with a lock catch.

In the present embodiment, the drill 8 has a diameter of 1.5 mm.

In conclusion, the device has high automation degree, avoids errors caused by manual drilling during drilling, and improves the testing precision because testers do not need to contact with workpieces during the measurement of the residual stress of large-sized workpieces.

Drawings

FIG. 1 is a diagram showing the positional relationship between the apparatus and a test workpiece.

Fig. 2 is a schematic structural view of the device.

Fig. 3 is a schematic view of the present apparatus X, Y, Z shaft translation station, drill and drill bit.

Fig. 4 is a schematic structural diagram of the adjusting bracket and the high-definition camera of the device.

In the drawings: 1. the device comprises an X-axis moving table, a 2 and Y-axis moving table, a 3 and Z-axis moving table, 4, a pulley, 5, an adjusting bracket, 6, a high-definition camera, 7, a drilling machine, 8, a drill bit, 9 and a test workpiece.

Detailed Description

The present invention will be further described with reference to the following detailed description.

Referring to fig. 1-4, a precision drilling device for testing residual stress of a large workpiece comprises an XYZ three-axis moving platform, wherein the XYZ three-axis moving platform comprises a support bracket 10, an X-axis moving platform 1, a Y-axis moving platform 2 and a Z-axis moving platform 3, the support bracket 10 is arranged above a test workpiece 9 in a crossing manner, pulleys 4 are mounted at the bottoms of supporting legs of the support bracket 10, the pulleys 4 are universal pulleys with latches, the X-axis moving platform 1 is mounted on the support bracket 10, the Y-axis moving platform 2 is mounted on the X-axis moving platform 1, the Z-axis moving platform 3 is mounted on the Y-axis moving platform 2, a drilling machine 7 and a high definition camera 6 are mounted on the Z-axis moving platform 3, a drilling head 8 of the drilling machine 7 faces the test workpiece 9, the diameter of the drilling head 8 is 1.5mm, the high definition camera 6 is mounted on a moving end of the XYZ three-axis moving platform through an adjusting bracket 5, the adjusting bracket 5 is composed of three sections of connecting rods which are connected with each other through a spherical hinge capable of locking the angle,

when in use, firstly, the surface of a workpiece 9 to be tested is polished, the surface is wiped by alcohol, a strain gage is pasted, a lead is welded and a residual stress tester is connected. Then the device is moved to the local position of the workpiece where the test point is located, and the pulley is locked, so that the test vehicle cannot move freely. Roughly adjusting an X, Y, Z-axis moving table to enable the drill bit to move to the position of the strain gauge and enable the drill bit to be about 1mm away from the workpiece, adjusting a high-definition camera 6 to enable the high-definition camera 6 to be aligned with the drill bit, starting the high-definition camera 6 to amplify the position of the strain gauge and the drill bit, finely adjusting a X, Y-axis moving table to enable the drill bit 8 to be aligned with the center of the strain gauge, and then automatically descending the Z-axis moving table to enable the drill bit to be in contact with the center of the strain gauge. And resetting the data of the strain gauge, starting a drilling machine, setting a downward drilling hole for 2mm, slowly moving the drill bit downward along the Z axis, and after the hole depth reaches 2mm, moving the drill bit upward to a safe position, so that the drilling is finished. When testing the second point residual stress, if the second point is near the first point, need not to remove the test car, if far away from the first point, then need unblock pulley, remove to the second point position, test.

The above examples are merely illustrative of the present invention clearly and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. Nor is it intended to be exhaustive of all embodiments. And obvious changes and modifications may be made without departing from the scope of the present invention.

Claims

1. The utility model provides a test large-scale work piece residual stress's precision drilling device which characterized in that: the device comprises an XYZ three-axis moving platform, wherein a drilling machine (7) and a high-definition camera (6) are fixed on the moving end of the XYZ three-axis moving platform, a drill bit (8) of the drilling machine (7) faces a test workpiece (9), a lens of the high-definition camera (6) faces the drill bit drilling end, and the high-definition camera (6) is connected with an observation screen in a wireless or wired mode.

2. The precision drilling device for testing the residual stress of the large-sized workpiece according to claim 1, characterized in that: the high-definition camera (6) is installed on the moving end of the XYZ three-axis moving platform through an adjusting support (5).

3. The precision drilling device for testing the residual stress of the large-sized workpiece according to claim 2, characterized in that: the adjusting bracket (5) is composed of three sections of connecting rods, and the connecting rods are connected with each other through a spherical hinge capable of locking the angle.

4. The precision drilling device for testing the residual stress of the large-sized workpiece according to claim 1, characterized in that: the XYZ three-axis moving platform comprises a supporting bracket (10), an X-axis moving platform (1), a Y-axis moving platform (2) and a Z-axis moving platform (3), wherein the supporting bracket (10) stretches over a test workpiece (9), the X-axis moving platform (1) is installed on the supporting bracket (10), the Y-axis moving platform (2) is installed on the X-axis moving platform (1), the Z-axis moving platform (3) is installed on the Y-axis moving platform (2), and a drilling machine (7) and a high-definition camera (6) are installed on the Z-axis moving platform (3).

5. The precision drilling device for testing the residual stress of the large-sized workpiece according to claim 4, characterized in that: and a pulley (4) is installed at the bottom of the supporting foot of the supporting bracket (10), and the pulley (4) is an universal pulley with a lock catch.

6. The precision drilling device for testing the residual stress of the large-sized workpiece according to claim 1, characterized in that: the diameter of the drill bit (8) is 1.5 mm.