CN104475805A - High-precision perforating device for testing residual stress - Google Patents

Abstract

A high-precision drilling device for testing residual stress, including a centering part and a punching part. The centering part is composed of an adsorption magnet, an adjustment bracket, a dial indicator, a centering microscope and a microscope sleeve. The punching part has a knife head and center drill; the cutter head is adsorbed with an adsorption magnet, and an adjustment bracket is arranged on one side of the adsorption magnet, and a dial indicator is connected under the adjustment bracket; a center drill is installed under the cutter head; a centering microscope is placed under the center drill, and a centering microscope The jacket has a microscope sleeve, a powerful magnet is arranged at the bottom of the microscope sleeve, and a dial indicator measuring head is arranged on the dial indicator. The device utilizes the precision of the numerical control machine tool itself to ensure the drilling precision, and can accurately center, thereby realizing precise drilling and solving the defects of the prior art.

Description

A high-precision drilling device for testing residual stress

technical field

The invention relates to a residual stress testing device, in particular to a high-precision drilling device for testing residual stress.

Background technique

During the manufacturing process, the component will be affected and affected by various processes and other factors. When these influencing factors disappear, some residual effects and influences will remain inside the component, resulting in residual stress. The existence of residual stress has a significant impact on the strength and structural deformation of components. Therefore, the test of residual stress is of great significance to production and scientific experiments.

The detection of residual stress has been carried out for many years at home and abroad, and its measurement methods can be divided into mechanical measurement methods and physical measurement methods. In the mechanical measurement method, the part must be separated or divided to release the stress, which will cause certain damage or even destruction to the workpiece. Typical methods include grooving and drilling. The technology in this area is mature and the theory is perfect. Among them, the small-diameter blind hole method has become a standard test method for on-site measurement because of its less damage to the workpiece and more reliable measurement (see ASTM E837-99). In actual production and application, the key issue of the blind hole method is the precision and accuracy of centering and punching. In the existing residual stress drilling devices, most of them use a microscope for centering, and the electric hand drill clamps the drill bit for drilling. This method has the following disadvantages: 1. The processing accuracy of the electric hand drill itself is poor, and often The process of drilling and centering causes a large deviation, which affects the measurement results; 2. The drill bit is prone to vibration and angle deflection during the drilling process, which damages the roundness of the hole, thus failing to guarantee its precision requirements.

Contents of the invention

In order to solve the deficiencies of the prior art, the present invention provides a high-precision drilling device for testing residual stress.

A high-precision drilling device for testing residual stress, including a centering part and a punching part. The centering part is composed of an adsorption magnet, an adjustment bracket, a dial indicator, a centering microscope and a microscope sleeve. The punching part has a knife head and center drill; the cutter head is adsorbed with an adsorption magnet, and an adjustment bracket is arranged on one side of the adsorption magnet, and a dial indicator is connected under the adjustment bracket; a center drill is installed under the cutter head; a centering microscope is placed under the center drill, and a centering microscope The jacket has a microscope sleeve, a powerful magnet is arranged at the bottom of the microscope sleeve, and a dial indicator measuring head is arranged on the dial indicator.

The connection between the centering microscope and the microscope sleeve adopts a transition fit installation.

The outer circle of the microscope sleeve is finished by a cylindrical grinder, and the coaxiality between the outer circle of the microscope sleeve and the centering microscope is φ0.01 mm.

A light opening is provided at the lower part of the outer wall of the microscope sleeve. The light opening is preferably rectangular.

Preferably, the number of powerful magnets (5) arranged at the bottom end of the microscope sleeve is 3-8.

In order to facilitate adjustment, the adjustment bracket is composed of two brackets, and the middle is connected by a rotatable connection.

The invention is scientific and reasonable, and the design is ingenious. An adsorption magnet is adsorbed on the cutter head, and the adsorption magnet is connected to the dial indicator through the adjustment bracket. Both the adsorption magnet and the adjustment bracket facilitate the movement of the dial indicator for angle adjustment and centering calibration. The centering microscope is covered with a microscope sleeve, and the bottom of the microscope sleeve is provided with a powerful magnet to fix the position, so that the centering microscope can be placed on the measured component more stably. The position of the lower part of the outer wall of the microscope sleeve is provided with a rectangular light opening, which is convenient for turning on the illuminating light for observation and centering. The outer circle of the microscope sleeve is finished by a cylindrical grinder, and the coaxiality between the outer circle of the microscope sleeve and the inner hole of the microscope is good, so as to ensure that the cross center of the centering microscope coincides with the axis of the outer circle of the microscope sleeve to complete the function of precise centering .

Description of drawings

Figure 1 is a front view of the device of the present invention.

Figure 2 is a perspective view of the microscope sleeve.

Figure 3 is a front view of the centering microscope.

The corresponding marks and parts in the figure are: 1. The measured component, 2. Microscope sleeve, 3. Rectangular light opening, 4. Centering microscope, 5. Powerful magnet, 6. Cutter head, 7. Dial indicator, 8. Adjust the bracket, 9. Adsorption magnet, 10- dial indicator probe, 11- center drill.

specific embodiment

See Figure 1-3. A high-precision drilling device for testing residual stress. The centering part is composed of an adsorption magnet 9, an adjustment bracket 8, a dial indicator 7, a centering microscope 4 and a microscope sleeve 2. The drilling part has a cutter head 6 and a center drill 11. The cutter head 6 is adsorbed with an adsorption magnet 9, and one side of the adsorption magnet 9 is provided with an adjustment bracket 8, and a dial gauge 7 is connected below the adjustment bracket 8; a center drill 11 is installed below the cutter head 6; The microscope 4 is covered with a microscope sleeve 2 on the centering microscope 4, and four powerful magnets 5 are evenly distributed at the bottom of the microscope sleeve 2, and the dial gauge 7 is provided with a dial gauge measuring head 10.

The centering microscope 4 and the microscope sleeve 2 are connected by a transition fit installation. The outer circle of the microscope sleeve 2 is finished by a cylindrical grinder, and the coaxiality between the outer circle of the microscope sleeve 2 and the centering microscope 4 is φ0.01 mm.

A rectangular light opening 3 is provided at the lower part of the outer wall of the microscope sleeve 2 .

The adjustment bracket 8 is composed of two sections of brackets, which are connected in a rotatable connection mode in the middle.

When using, first of all, under the premise of not destroying the original residual stress field, polish and clean the test part of the component under test 1, mark the test part with a stylus, and use 502 glue to paste the strain rosette according to the strain General method Accurately paste on the component under test, and ensure that the cross mark on the rosette coincides with the marked mark.

Place the microscope sleeve 2 on the measured component 1, and due to the action of the powerful magnet 5, the microscope sleeve 2 can be stabilized on the measured component 1, and adjust the position of the microscope sleeve 2 so that the strain rosette is located inside the sleeve hole 2; Turn on the lighting (peripheral), the light reaches the inside of the sleeve 2 through the rectangular light opening 3, use the centering microscope 4 to observe the position of the strain flower cross, and constantly adjust the position of the sleeve to ensure that the center cross of the microscope 4 is consistent with the strain flower cross coincide.

Move the CNC machine tool head 6 to the place directly above the microscope 4, install the dial indicator 7 on the adjustment bracket 8, and let the adsorption magnet 9 on the other end of the adjustment bracket 8 be fixed on the CNC machine tool head 6 to ensure that there is no On the premise of touching the microscope sleeve 2, the dial gauge measuring head 10 is in good contact with the outer circle of the microscope sleeve 2.

To control the low-speed rotation of the spindle of the CNC machine tool, the dial indicator probe 10 will rotate around the microscope sleeve 2 while the spindle rotates, and control the swing of the pointer of the dial gauge 7 by fine-tuning the X-axis and Y-axis of the CNC machine tool. The swing range ensures that the central axis of the microscope sleeve 2 and the central deviation of the CNC machine tool center drill 11 are within 0.01 mm.

Finally, remove the microscope sleeve 2 and the powerful magnet 5. In order to reduce the heat generated during the drilling process and improve the drilling accuracy, the spindle speed of the CNC machine tool is controlled to be about 50r/min, and the center drill 11 is controlled to move slowly along the Z axis. Move down; after reaching the preset hole depth, the control center drill 11 moves vertically upwards to a safe position. At this point, the punching is over.

The present invention utilizes the precision of the numerical control machine tool itself to ensure the drilling precision, thereby realizing precise drilling.

Claims (7)

1. test the high-accuracy perforating device of residual stress for one kind, comprise centering part and perforation, it is characterized in that: centering part is by adsorption magnet (9), adjusting pole (8), dial gauge (7), form heart microscope (4) and microscope sleeve (2), and perforation has cutter head (6) and centre drill (11); Cutter head (6) is adsorbed with adsorption magnet (9), and adsorption magnet (9) side is provided with adjusting pole (8), and adjusting pole (8) below is connected with dial gauge (7); Cutter head (6) below is provided with centre drill (11); Centre drill (11) below is placed with heart microscope (4), and have microscope sleeve (2) to heart microscope (4) overcoat, microscope sleeve (2) bottom arranges strong magnets (5), and dial gauge (7) arranges dial gauge gauge head (10).

2. perforating device according to claim 1, is characterized in that: adopt heart microscope (4) and microscope sleeve (2) and excessively coordinate the connected mode of installing.

3. perforating device according to claim 1, is characterized in that: microscope sleeve (2) cylindrical adopts cylindrical grinder fine finishining, microscope sleeve (2) cylindrical be φ 0.01 millimeter to the axiality of heart microscope (4).

4. perforating device according to claim 1, is characterized in that: the position of microscope sleeve (2) outer wall bottom is provided with Tong Guangkou (3).

5. perforating device according to claim 4, is characterized in that: Tong Guangkou (3) is rectangle.

6. perforating device according to claim 1, is characterized in that: the quantity of the strong magnets (5) that microscope sleeve (2) bottom is arranged is 3-8.

7. perforating device according to claim 1, is characterized in that: adjusting pole (8) is two sections and is configured to, and middle employing is rotatably connected mode and connects.