Method for precision boring of wheel taper

Abstract

The application discloses a wheel taper precision boring machining method, comprising the following steps: S1, providing machining equipment, machining tools and measuring tools; S2, the machining equipment controls the machining tools to move in the axial Z axis and the radial X axis linkage, so that the trajectory of the machining tool tip cuts the wheel according to the taper requirement; S3, the sample wheel comparison measurement method is adopted, and the wheel taper precision boring size is measured and adjusted by taking the three-coordinate calibrated sample wheel as the reference. The wheel taper precision boring machining method establishes a complete set of standard processes for high-precision wheel taper precision boring production, realizes the overall arrangement of various elements such as machine tools, tools, measurement and control means, and can improve the machining precision and machining stability.

Description

Technical Field

[0001] This invention belongs to the field of high-precision wheel deep machining, specifically relating to a method for machining wheel taper precision boring holes. Background Technology

[0002] The wheel rim holes of rail vehicles are the main parts for mounting axles, and the requirements for dimensions and surface roughness are very high. In recent years, the machining of the inner holes of some subway wheels has added a requirement of 1:300 taper. The realization of this taper precision boring requires solving the problem of precise positioning of the inner and outer hub surfaces of the wheel rim, ensuring a smooth transition of the rounded corners of the hole, and at the same time, solving the problem of measuring the dimensions of the taper hole. There are problems of high machining difficulty and high dimensional measurement difficulty, resulting in poor machining stability.

[0003] Chinese patent application number 201910577989.5 discloses a high-life, crack-resistant, and deformation-resistant pipe mold and its manufacturing method, which improves the mold's service life by optimizing the material composition, enhancing heat treatment performance, improving the finishing process route, and optimizing processing parameters. The specific production process is as follows: electric furnace smelting + vacuum refining → heating → upsetting, drawing, and forging using a 5000-ton hydraulic press → normalizing + tempering after forging → straightening → surface inspection, blanking, and physical and chemical testing (low magnification, non-metallic inclusions, ultrasonic flaw detection). → Rough machining → Tempering and heat treatment → Physical and chemical testing (grain size, metallographic testing, mechanical properties (two-dimensional tensile and three-dimensional tensile testing), ultrasonic flaw detection), inspection, blanking → Fine machining to finished size → Magnetic particle testing, dimensional inspection → Delivery. By improving the composition ratio of the tube mold material, the hardness and mechanical properties of the tube mold are improved. By improving the forging and heat treatment processes, and optimizing the processing technology and methods for deep hole precision boring and precision turning of the tube body, the goal is to improve the service life of the tube mold, and ultimately extend the service life of the tube mold and improve its cost performance.

[0004] Chinese Patent Application No. 200710119992.X discloses a process method for precisely positioning and accurately boring an impression cylinder. The steps include: initial alignment of the bearing seat for coaxiality; positioning the cylinder shaft diameter of the semi-finished impression cylinder on the bearing seat; re-measuring various data; measuring the semi-finished impression cylinder using two measuring blocks; calculating the actual distance between the roller and the measuring blocks to locate the hole to be bored; roughing and fine boring the operating surface of the semi-finished impression cylinder in one direction until the finished product is reached, and checking its parallelism and symmetry; boring the transmission surface of the semi-finished impression cylinder in the same manner as the operating surface; and finally, removing the bored semi-finished impression cylinder to complete the boring process. This method allows for precise positioning and accurate boring without a particularly cumbersome process flow, making it convenient to operate and particularly suitable for boring high-precision impression cylinders.

[0005] It is desirable to provide an improved method for precision boring of wheel tapers, particularly a solution for improving the precision of precision boring of wheel tapers. Summary of the Invention

[0006] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention provides a method for precision boring of wheel tapers, with the aim of improving machining accuracy.

[0007] To achieve the above objectives, the technical solution adopted by the present invention is: a method for precision boring of wheel tapers, comprising the following steps:

[0008] S1. Provide processing equipment, cutting tools and measuring instruments;

[0009] S2. The machining equipment controls the machining tool to move in conjunction with the axial Z-axis and radial X-axis, so that the trajectory of the machining tool tip cuts the wheel according to the taper requirements;

[0010] S3. Using the sample wheel comparison measurement method, the wheel tapered precision boring hole size is measured and adjusted based on the sample wheel calibrated by the three coordinate system.

[0011] A vertical lathe is selected as the machining equipment. The two-axis linkage function of the vertical lathe is used to perform precision boring of wheel taper by rotating the faceplate and feeding in the X direction.

[0012] A deep hole machining turning tool holder capable of mounting at least two of the aforementioned machining tools is used to achieve precision boring of wheel tapers without tool changes.

[0013] The measuring tool includes a measuring dial indicator. In step S3, during measurement, one end of the measuring tool is fixed, and the other end uses the elastic rod of the measuring dial indicator as the measuring point. The measuring tool restricts four degrees of freedom, including the degrees of freedom of movement along the Z-axis, rotation along the Z-axis, movement along the X-axis, and rotation around the Y-axis. By rotating along the X-axis and moving around the Y-axis, the maximum distance of the cylindrical surface of the wheel taper precision boring hole is found from the rebound point on the measuring dial indicator.

[0014] The measuring tool also includes a ruler body, and the measuring gauge is connected to the ruler body. In step S3, during measurement, the limiting rod is in contact with the wheel surface, and the measuring gauge is located in the wheel taper precision boring hole.

[0015] The measuring instrument also includes a probe, which is mounted on the ruler. The probe and the measuring instrument are arranged opposite each other. In step S3, during measurement, the probe contacts the cylindrical surface of the wheel taper precision boring hole.

[0016] The specific method of sample wheel comparison measurement is as follows: First, a sample wheel is calibrated using a three-coordinate measuring machine to obtain accurate precision boring values. The sample wheel is then used after being placed for a preset time. In actual production, a tapered precision boring comparison measuring tool is used to adjust the precision boring values ​​at a preset distance downward from the outer rim surface calibrated by the three-coordinate measuring machine. Two sets of data are measured for each wheel at 90° positions on both the upper and lower layers, and adjustments are made based on the dimensions marked on the drawings.

[0017] The preset time is no less than 24 hours.

[0018] The preset distance is no less than 30mm.

[0019] The wheel taper precision boring method of the present invention establishes a complete standard process for the production of high-precision wheel taper precision boring, realizes the overall arrangement of various elements such as machine tools, cutting tools, measurement and control means, and can improve machining accuracy and machining stability. Attached Figure Description

[0020] This manual includes the following figures, which illustrate the following:

[0021] Figure 1 This is a flowchart illustrating the wheel taper precision boring method of the present invention;

[0022] Figure 2 This is a schematic diagram of a deep hole machining turning tool holder;

[0023] Figure 3 This is a schematic diagram of the comparison method measurement process;

[0024] Figure 4 This is a schematic diagram of the high-precision wheel taper precision boring drawing requirements;

[0025] The diagram is marked as follows:

[0026] 1. Ruler body; 2. Measuring gauge; 3. Set screw; 4. Hex nut; 5. Probe; 6. 1:300 taper hole; 7. First surface; 8. Second surface. Detailed Implementation

[0027] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the concept and technical solutions of the present invention, and to facilitate its implementation.

[0028] like Figure 1 As shown, the present invention provides a method for precision boring of wheel taper, comprising the following steps:

[0029] S1. Provide processing equipment, cutting tools and measuring instruments;

[0030] S2. The machining equipment controls the machining tool to move in conjunction with the axial Z-axis and radial X-axis, so that the trajectory of the machining tool tip cuts the wheel according to the taper requirements;

[0031] S3. Using the sample wheel comparison measurement method, the wheel tapered precision boring hole size is measured and adjusted based on the sample wheel calibrated by the three coordinate system.

[0032] Specifically, as can be seen from the process flow, precision boring is the final step in wheel machining, and its quality directly affects the overall quality of the wheel. The industry standard for tapered precision boring typically employs a multi-stage process, including semi-finishing, oil groove machining, tapered precision boring, and manual tool setting for machining the inner and outer surface arc angles twice. Dimensional control of the tapered precision boring relies on coordinate measuring machines (CMMs). This process is complex, lengthy, and requires significant investment in labor and equipment. To overcome the shortcomings of the current process flow, this invention improves and innovates by coordinating the process, machine tools, and cutting tools to establish a standardized process for tapered precision boring of wheels. This process optimizes various aspects to improve machining accuracy and increase product yield.

[0033] In this invention, the process of high-precision wheel taper boring is strictly controlled, including the selection of vertical lathes, the use of deep hole machining turning tool holders, the selection of special measuring tools, and the use of sample wheel comparison method for dimensional control. These aspects are rationally optimized.

[0034] In step S1 above, a vertical lathe is selected as the machining equipment. The two-axis linkage function of the vertical lathe is used to perform precision boring of the wheel taper by rotating the faceplate and feeding in the X direction.

[0035] In this invention, the tapered precision boring tool must meet the following requirements: 1. The tool must have high rigidity to meet the requirements of high-speed deep hole machining. 2. High repeatability positioning accuracy, eliminating the need for tool setting in the X direction every time when machining batches of parts. 3. Strong adaptability, capable of meeting the requirements of semi-precision boring, precision boring, oil groove machining, and upper and lower chamfering.

[0036] In step S1 above, a deep hole turning tool holder capable of mounting at least two machining tools is used to achieve precision boring of wheel tapers without tool changing. In this invention, a deep hole turning tool holder is employed. Because taper hole machining requires simultaneous machining of upper and lower chamfers, oil grooves, semi-finish boring, and finish boring, current spindle tool changers are square tool holders. The tool holder is tightened by a BT50 tool holder at the upper end, and locked by a transverse groove structure and a disc positioning block at the lower end. During machining, metal chips easily adhere to the disc positioning block, causing X-axis and Z-axis offset and resulting in machining defects. Therefore, a deep hole turning tool holder capable of mounting two machining tools (such as...) is used. Figure 2 As shown in the figure, it can meet the machining requirements without changing the tool, thus increasing the machining stability.

[0037] The deep hole machining turning tool holder has a maximum depth of 300mm, reducing the length of the transverse groove structure and the area of ​​the disc, preventing chip trapping. Tool holders are designed on both the left and right sides of the deep hole machining turning tool holder. Tools can be mounted horizontally or vertically on the tool holder. The length direction of horizontally mounted tools is perpendicular to the length direction of the tool holder, while the length direction of vertically mounted tools is parallel to the length direction of the tool holder. This meets the machining requirements of chamfering, oil grooves, rough and fine boring, etc. Utilizing two tool offsets on the same tool holder, high-precision machining of the entire internal cavity can be completed without changing tools, eliminating the risk of tool changes and increasing machining stability.

[0038] In step S2 above, the machining process of the taper precision boring hole includes the following steps:

[0039] S201. Using CNC programming on a CNC machining center, the machining of tapered precision boring holes is achieved through programming of the CNC system.

[0040] S202. The CNC system controls the movement of the machine tool's coordinate axes based on the input taper parameters, hole size parameters, and machining process requirements.

[0041] S203. By controlling the machining tool to move in conjunction with the axial Z-axis and radial X-axis, the trajectory of the boring tool tip is made to cut according to the taper requirements.

[0042] In this invention, such as Figure 3 As shown, the measuring tool includes a measuring dial indicator. In step S3 above, during measurement, one end of the measuring tool is fixed, and the other end uses the elastic rod of the measuring dial indicator as the measuring point. The measuring tool restricts four degrees of freedom, including movement along the Z-axis, rotation along the Z-axis, movement along the X-axis, and rotation around the Y-axis. By rotating around the X-axis and moving along the Y-axis, the maximum distance of the cylindrical surface of the wheel taper precision boring hole is found from the rebound point on the measuring dial indicator. The Z-axis is perpendicular to the X-axis and Y-axis, and the X-axis is perpendicular to the Y-axis. The X-axis is the axis of the wheel, and the Z-axis and Y-axis are perpendicular to the axis of the wheel.

[0043] In this invention, the measuring instrument is a dial indicator, which can control the accuracy to 0.001mm. Furthermore, since the measuring instrument is attached to the surface of the wheel, human measurement error is basically eliminated.

[0044] In this invention, such as Figure 3 As shown, the measuring instrument also includes a ruler body, and the measuring dial is connected to the ruler body. In step S3 above, during measurement, the limiting rod is in contact with the wheel surface, and the measuring dial is located in the wheel taper precision boring hole.

[0045] In this invention, such as Figure 3As shown, the measuring instrument also includes a probe, which is mounted on the ruler body and arranged opposite to the measuring gauge. The probe and measuring gauge are fixedly mounted on the ruler body, located on the same side of the ruler body, and aligned on a straight line parallel to the length direction of the ruler body. In step S3 above, during measurement, the probe and measuring gauge are located in the wheel taper precision boring hole, with the probe contacting the cylindrical surface of the wheel taper precision boring hole, and the ruler body contacting the top surface of the wheel, positioned above the wheel.

[0046] In step S3 above, the sample wheel comparison measurement method is as follows: First, a sample wheel is calibrated using a three-coordinate measuring machine to obtain accurate precision boring values. The sample wheel is used after being placed for a preset time. In actual production, a tapered precision boring comparison measuring tool is used to adjust the precision boring values ​​at a preset distance downward from the outer rim surface calibrated by the three-coordinate measuring machine. Two sets of data are measured for each wheel at 90° positions on both the upper and lower layers. Adjustments are made based on the dimensions marked on the drawing.

[0047] In step S3 above, the preset time is no less than 24 hours. The preset distance is no less than 30mm.

[0048] In step S3 above, based on experience and data analysis of long-term precision boring hole dimensional control, a sample wheel comparison measurement was adopted as the standard for measuring the precision boring hole dimensions of the tapered hole. First, a sample wheel was calibrated using a coordinate measuring machine to provide accurate precision boring hole values. The sample wheel was placed on-site for 24 hours before use. In actual production, a tapered precision boring hole comparison gauge was used, and the precision boring hole values ​​were adjusted to be 30mm downwards from the outer rim surface as determined by the coordinate measuring machine (e.g.,...). Figure 3 As shown), two sets of data were measured for each wheel at 90° angles on both the upper and lower layers. Adjustments were made based on the dimensions marked on the drawings, with the tread runout ensured by alignment, and cylindricity controlled to not exceed 0.02mm unless otherwise specified.

[0049] By using a sample wheel comparison method, errors caused by the machining environment, temperature, and human measurement are minimized, thereby improving measurement accuracy. The dimensions of the taper precision boring hole are controlled by using sample wheel calibration dimensions under the same environmental conditions, reducing the differences in temperature deformation response between ring gauges and wheels of different sizes. This control method has been verified as highly effective through coordinate measuring machine (CMM) testing and field practice.

[0050] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution; or the direct application of the inventive concept and technical solution to other situations without modification, are all within the protection scope of the present invention.

Claims

1. A method for precision boring of wheel tapers, characterized in that, Including the following steps: S1. Provide processing equipment, cutting tools and measuring instruments; S2. The machining equipment controls the machining tool to move in conjunction with the axial Z-axis and radial X-axis, so that the trajectory of the machining tool tip cuts the wheel according to the taper requirements; S3. Using the sample wheel comparison measurement method, the wheel tapered precision boring hole size is measured and adjusted based on the sample wheel calibrated by the three coordinate system.

2. The method for machining wheel taper precision boring according to claim 1, characterized in that, A vertical lathe is selected as the machining equipment. The two-axis linkage function of the vertical lathe is used to perform precision boring of wheel taper by rotating the faceplate and feeding in the X direction.

3. The method for machining wheel taper precision boring according to claim 1, characterized in that, A deep hole machining turning tool holder capable of mounting at least two of the aforementioned machining tools is used to achieve precision boring of wheel tapers without tool changes.

4. The method for machining wheel taper precision boring according to any one of claims 1 to 3, characterized in that, The measuring tool includes a measuring dial indicator. In step S3, during measurement, one end of the measuring tool is fixed, and the other end uses the elastic rod of the measuring dial indicator as the measuring point. The measuring tool restricts four degrees of freedom, including the degrees of freedom of movement along the Z-axis, rotation along the Z-axis, movement along the X-axis, and rotation around the Y-axis. By rotating along the X-axis and moving around the Y-axis, the maximum distance of the cylindrical surface of the wheel taper precision boring hole is found from the rebound point on the measuring dial indicator.

5. The method for machining wheel taper precision boring holes according to claim 4, characterized in that, The measuring tool also includes a ruler body, and the measuring gauge is connected to the ruler body. In step S3, during measurement, the limiting rod is in contact with the wheel surface, and the measuring gauge is located in the wheel taper precision boring hole.

6. The method for machining wheel taper precision boring holes according to claim 5, characterized in that, The measuring instrument also includes a probe, which is mounted on the ruler. The probe and the measuring instrument are arranged opposite each other. In step S3, during measurement, the probe contacts the cylindrical surface of the wheel taper precision boring hole.

7. The method for machining wheel taper precision boring holes according to any one of claims 1 to 3, characterized in that, The specific method of sample wheel comparison measurement is as follows: First, a sample wheel is calibrated using a three-coordinate measuring machine to obtain accurate precision boring values. The sample wheel is then used after being placed for a preset time. In actual production, a tapered precision boring comparison measuring tool is used to adjust the precision boring values ​​at a preset distance downward from the outer rim surface calibrated by the three-coordinate measuring machine. Two sets of data are measured for each wheel at 90° positions on both the upper and lower layers, and adjustments are made based on the dimensions marked on the drawings.

8. The method for machining wheel taper precision boring holes according to claim 7, characterized in that, The preset time is no less than 24 hours.

9. The method for machining wheel taper precision boring holes according to claim 7, characterized in that, The preset distance is no less than 30mm.

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