CN114154256A - Machining process for three-dimensional special-shaped rod part - Google Patents
Machining process for three-dimensional special-shaped rod part Download PDFInfo
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- CN114154256A CN114154256A CN202111238868.1A CN202111238868A CN114154256A CN 114154256 A CN114154256 A CN 114154256A CN 202111238868 A CN202111238868 A CN 202111238868A CN 114154256 A CN114154256 A CN 114154256A
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- 238000003754 machining Methods 0.000 title claims abstract description 34
- 238000005242 forging Methods 0.000 claims abstract description 24
- 238000005520 cutting process Methods 0.000 claims abstract description 23
- 238000012545 processing Methods 0.000 claims abstract description 17
- 238000000034 method Methods 0.000 claims abstract description 16
- 238000005259 measurement Methods 0.000 claims abstract description 11
- 238000003801 milling Methods 0.000 claims abstract description 9
- 238000007514 turning Methods 0.000 claims description 11
- 238000007689 inspection Methods 0.000 claims description 3
- 239000006247 magnetic powder Substances 0.000 claims description 3
- 238000004806 packaging method and process Methods 0.000 claims description 3
- 238000009966 trimming Methods 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 239000002699 waste material Substances 0.000 abstract description 3
- 239000000463 material Substances 0.000 description 7
- 238000013461 design Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005495 investment casting Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 230000002950 deficient Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/20—Design optimisation, verification or simulation
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- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F30/00—Computer-aided design [CAD]
- G06F30/10—Geometric CAD
- G06F30/17—Mechanical parametric or variational design
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Abstract
The invention relates to a three-dimensional special-shaped rod part machining process, which comprises the following steps: blanking; roughly forging a blank, and reserving machining allowance in the height and thickness directions; roughly milling a datum plane for subsequent measurement and processing positioning; measuring the contour of the forging blank by using a video measuring instrument and converting the contour of the forging blank into a DWG/DXF format graph; reading in the outline of the blank by using CAD drawing software, introducing the actual appearance of the product, and determining a linear cutting machining reference according to the shape of the blank; according to the datum point given by the CAD, the shape of the part in the height direction and the thickness direction is cut in a linear mode; and (5) secondary clamping and linear cutting of the shape in the width direction. According to the invention, the three-dimensional special-shaped long rod piece is processed by using the process scheme of combining the forging blank with the processing of the machine, so that the production cost is effectively reduced, and the production efficiency is improved. The video measurement is combined with CAD software to determine the processing line cutting processing reference, thereby effectively avoiding the waste caused by the deformation of the blank and greatly improving the finished product rate and the processing efficiency of the parts.
Description
Technical Field
The invention belongs to the field of machining of high-speed railway products, and particularly relates to a machining process of a three-dimensional special-shaped rod part.
Background
When manufacturing a special long rod for pushing action in a brake clamp of a high-speed rail, the special long rod belongs to a three-dimensional special long rod part, the section of the special long rod part is 10 multiplied by 10 square, the unfolding length is about 250mm, and the special long rod part has distance difference of 171.5/16/52.5mm in three directions of space X/Y/Z.
Due to the structural limitations and performance requirements of the parts involved, the parts have the following difficulties in practical production:
(1) after the slender spatial special-shaped rod is subjected to precision forging forming, the spatial size of a product is not easy to guarantee due to internal stress, and the forging difficulty is high;
(2) the precision forging die has complex design, high cost and long development period, and is not suitable for the early-stage trial production of products;
(3) the raw material is directly machined by a material machine, the material cutting rate is up to 93 percent, the raw material waste is serious, and the product performance is not easy to guarantee;
(4) the material is directly processed, and because the right end of the three-dimensional special-shaped rod piece is provided with the ball head and the annular groove, five-axis machine tools are needed for milling, the processing programming difficulty is high, the production period is long, the deformation of parts after processing is large, and the yield is low;
(5) the axes of the ball head at the right end of the part, the annular groove and the rod body at the left end of the part have 16 mm and 52.5mm eccentricity in two directions of Y, Z respectively, and the processing rotating shaft of the part is outside a part entity, so the turning processing difficulty is high.
Disclosure of Invention
The invention aims to provide a three-dimensional special-shaped rod part processing technology, which effectively solves the problems of long cycle, high cost, low machining efficiency, yield and the like of precision forging and precision casting of three-dimensional special-shaped long rod parts.
The technical scheme adopted by the invention is as follows:
a three-dimensional special-shaped rod part machining process comprises the following steps:
firstly, blanking;
secondly, roughly forging the blank, and reserving machining allowance in the height direction and the thickness direction;
thirdly, roughly milling a reference surface for subsequent measurement and processing positioning;
measuring the outline of the forging blank by using a video measuring instrument and converting the outline into a DWG/DXF format graph;
reading the outline of the blank by using CAD drawing software, introducing the actual appearance of the product, and determining a linear cutting machining reference according to the shape of the blank;
sixthly, according to the datum point given by the CAD, the outline of the part in the height direction and the thickness direction is cut in a linear mode;
seventhly, secondary clamping and linear cutting of the shape in the width direction.
Further, in the third step, three planes of rough milling are used as the subsequent video measurement, the CAD determination reference and the positioning reference of the linear cutting shape, and the three planes are three adjacent planes which are perpendicular to each other.
Further, in the fourth step, the contour of the forged blank in the thickness direction is projected on a video measuring instrument, and the measured contour of the blank is output into a DWG or DXF format file which can be identified by two-dimensional drawing software by utilizing the file export function of the instrument.
Further, in the fifth step, firstly, two-dimensional drawing software is utilized to read in the blank outline output in the fourth step; secondly, introducing the outline of the product, completely containing the outline of the product in the outline of a forging blank, and enabling two sides to have larger allowance as far as possible; and finally, measuring the XY distance from the part shape datum point to the blank datum plane according to the position of the product shape wheel line on the blank forging contour, thereby determining the datum of the linear cutting machining.
And further, positioning the blank by using the reference plane machined in the third step in the sixth step, and linearly cutting the outline of the part in the height and thickness directions according to the machining reference determined in the fifth step.
Further, the method also comprises the following steps after the seventh step:
eighthly, clamping the outer circle of the left end by a lathe, and turning an inner hole to form;
ninth, turning a right end ball head and an annular groove by using the space positioning of a lathe fixture, and ensuring the space distance relationship between a left end hole of the part and a right end axis;
tenth, trimming the edge of the part appearance by a bench worker;
marking and lettering according to the requirements of the parts;
twelfth, magnetic powder inspection;
thirteen, packaging and warehousing.
Furthermore, in the eighth step, when the inner hole is turned by the numerical control lathe, when the cylindrical surface at the left end is clamped by the three-jaw chuck, the three-jaw positioning part needs to be trimmed into a pointed shape so as to leave the combined position of the cylindrical surface and the cross section of the rod body, and meanwhile, the special-shaped rod body warps out of the three-jaw chuck.
Further, in the lathe fixture in the ninth step, the three-dimensional space positioning surface is formed by linear cutting through a program for linearly cutting the part shape, so that the positioning surface of the fixture is highly attached to the part shape, and the positioning precision is ensured.
Further, in the lathe fixture in the ninth step, the axial positioning of the fixture is performed by using a left end cylinder of the part, and the positioning of the rod body perpendicular to the axial direction and the direction of the three-dimensional positioning surface is performed by using two cylindrical pins.
Further, a heat treatment step is also carried out between the second step and the third step.
The invention has the positive effects that:
1. the three-dimensional special-shaped long rod piece is processed by using the technical scheme of processing the forging blank by combining a machine, so that the production cost is effectively reduced, and the production efficiency is improved.
2. The video measurement is combined with CAD software to determine a machining line cutting machining reference, so that waste products caused by blank deformation are effectively avoided, and the finished product rate and the machining efficiency of parts are greatly improved;
3. the process method for determining the datum by combining video measurement with CAD assistance can be widely popularized to other process designs which are not easy to determine the processing datum, and better social benefits are obtained.
Drawings
FIG. 1 is a process flow diagram of the present invention;
FIG. 2 is a two-dimensional schematic view of a part of the present invention;
FIG. 3 is a schematic illustration of a forged blank and rough milling datum for a part according to the present invention;
FIG. 4 is a schematic view of a video measurement in conjunction with CAD determined referencing of a part according to the present invention;
FIG. 5 is a schematic view of the present invention relating to two wire-cutting forming of a part;
FIG. 6 is a turning clamp drawing of a right end ball head and an annular groove of a part.
Detailed Description
As shown in the attached fig. 1-5, the processing technology of the invention specifically comprises the following steps:
step one, sawing a bar stock.
And step two, forging the blank, wherein the thickness direction is large due to stress deformation, and the machining allowance is required to be 3-4mm, so that the condition that the blank is deformed due to stress to cause material loss and scrap of the outline of the finished part is avoided. In addition, the deformation in the height direction is small, so that the unilateral allowance can be reduced to 1-2 mm.
And step three, the mechanical property of the product is ensured through quenching and tempering.
And step four, milling three mutually vertical adjacent planes by the vertical milling machine for subsequent measurement and processing positioning.
And step five, measuring the contour of the forging blank by using a video measuring instrument and converting the contour into a DWG/DXF format.
The contour of the forging blank in the thickness direction is projected on a video measuring instrument (the deformation in the direction is large, and the phenomenon of material loss of a finished product is easy to occur), and the measured contour line of the forging blank is output into a DWG or DXF format file which can be identified by CAD software by utilizing the file export function of the instrument.
Reading the outline of the blank by using two-dimensional drawing software such as a CAXA electronic drawing board, AUOTOCAD and the like, and introducing an actual outline drawing of the product to enable the outline to be completely contained in the outline of the forged blank and enable two sides to have larger allowance as far as possible, so that the situation that the actual outline is scrapped due to material loss after cutting is avoided; and measuring the XY distance from the part shape datum point to the blank datum plane according to the position of the product shape wheel line on the blank forging contour, thereby determining the datum of linear cutting machining.
Because the external dimensions and the stress deformation of a batch of forged blanks are basically consistent, the difference between the projection detection of the blank outline and the determination of the finish machining reference basic dimension by combining CAD is not large, so that the batch of blanks can be projected to determine the positioning dimension of 1-2 pieces, and the production efficiency is improved on the premise of ensuring the yield.
And step seven, positioning by using the reference surface in the step four, and linearly cutting the outline (thickness shape) of the part in the height direction according to the reference point and the reference dimension given by the CAD.
And step eight, secondary clamping, namely positioning by using the first linear cutting shape and the left side reference surface in the step four, and linearly cutting the shape in the width direction.
And ninthly, clamping the outer circular surface of the left end of the part by using a numerical control lathe and a sharp-end soft three-jaw chuck, keeping away the combination position of the cylindrical surface and the cross section of the rod body, simultaneously warping the special-shaped rod body out of the three-jaw chuck, and turning an inner hole for forming.
When the inner hole is turned by the numerical control lathe, when the cylindrical surface at the left end is clamped by the three-jaw chuck, the three-jaw positioning part needs to be trimmed into a pointed shape so as to keep the combined position of the cylindrical surface and the cross section of the rod body away, and meanwhile, the special-shaped rod body warps out of the three-jaw chuck.
Step ten, turning a right end ball head and an annular groove by using the space positioning of a special lathe fixture, and ensuring the space distance relation between a left end hole of the part and the axis of the right end.
The lathe fixture with the space positioning function is designed and manufactured, the space appearance and the right end cylindrical surface positioning of a part are utilized, the axis of a right end ball head and the axis of an annular groove of the part are ensured to be consistent with the rotation center of the fixture and the main shaft of a machine tool, and therefore the size and the form and position tolerance of the finally turned part are ensured to meet the product requirements.
The specific structure of the lathe fixture is as shown in fig. 6, and the lathe fixture comprises a C-shaped fixture body 1, a bottom plate 2 arranged at the opening position of the fixture body 1, a positioning surface 3 arranged on the bottom plate 2 and an axial circular positioning groove 4 arranged at one end of the positioning surface 3, wherein the positioning surface 3 is an inclined plane, corresponds to one side surface of a workpiece, and is arranged on the bottom plate 2, and two radial positioning pins 5 are arranged on one side of the positioning surface 3 to prevent the workpiece from shaking on the plane. The axial circle positioning groove 4 corresponds to an axial circle on the end part of a workpiece.
The special turning tool is adopted to complete the turning of the three-dimensional special-shaped long rod, the part processing efficiency is improved, and the part yield is ensured.
And step eleven, trimming the outline edge of the part by a bench worker.
And step twelve, marking and lettering according to the requirements of the parts.
And step thirteen, magnetic powder inspection.
And step fourteen, packaging and warehousing.
The invention creatively provides a process method for determining a machining reference by combining video measurement and CAD drawing, solves the problem of scrapping of machined surface deficient materials caused by deformation of a special-shaped forging blank, and effectively improves the yield by more than 3 times. Meanwhile, the problems of long cycle, high cost and low machining efficiency of precision forging and precision casting of the three-dimensional special-shaped long rod part are solved.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (10)
1. A three-dimensional special-shaped rod part machining process is characterized by comprising the following steps:
firstly, blanking;
secondly, roughly forging the blank, and reserving machining allowance in the height direction and the thickness direction;
thirdly, roughly milling a reference surface for subsequent measurement and processing positioning;
measuring the outline of the forging blank by using a video measuring instrument and converting the outline into a DWG/DXF format graph;
reading the outline of the blank by using CAD drawing software, introducing the actual appearance of the product, and determining a linear cutting machining reference according to the shape of the blank;
sixthly, according to the datum point given by the CAD, the outline of the part in the height direction and the thickness direction is cut in a linear mode;
seventhly, secondary clamping and linear cutting of the shape in the width direction.
2. The process for machining a three-dimensional special-shaped rod part according to claim 1, wherein three planes of rough milling are used as a reference for subsequent video measurement, CAD determination and positioning of the line-cut profile in the third step, and the three planes are three adjacent planes perpendicular to each other.
3. The process of claim 1, wherein in step four, the contour of the forged blank in the thickness direction is projected on a video measuring instrument, and the measured contour of the forged blank is output to a file in DWG or DXF format that can be identified by two-dimensional drawing software by using the file export function of the instrument.
4. The process for machining a three-dimensional special-shaped rod part according to claim 1, wherein in step five, a two-dimensional drawing software is used to read in the outline of the blank output in step four; secondly, introducing the outline of the product, completely containing the outline of the product in the outline of a forging blank, and enabling two sides to have larger allowance as far as possible; and finally, measuring the XY distance from the part shape datum point to the blank datum plane according to the position of the product shape wheel line on the blank forging contour, thereby determining the datum of the linear cutting machining.
5. The process for machining a three-dimensional special-shaped rod part according to claim 1, wherein the blank is positioned by using the reference plane machined in the third step in the sixth step, and the contour of the part in the height and thickness directions is cut by a wire according to the machining reference determined in the fifth step.
6. The three-dimensional special-shaped rod part machining process according to claim 1, characterized by further comprising the following steps after the seventh step:
eighthly, clamping the outer circle of the left end by a lathe, and turning an inner hole to form;
ninth, turning a right end ball head and an annular groove by using the space positioning of a lathe fixture, and ensuring the space distance relationship between a left end hole of the part and a right end axis;
tenth, trimming the edge of the part appearance by a bench worker;
marking and lettering according to the requirements of the parts;
twelfth, magnetic powder inspection;
thirteen, packaging and warehousing.
7. The process for machining a three-dimensional special-shaped rod part according to claim 6, wherein in the eighth step, when the numerical control lathe is used for turning an inner hole and the three-jaw chuck is used for clamping the cylindrical surface at the left end, the three-jaw positioning part needs to be trimmed to be in a pointed shape so as to leave the combination position of the cylindrical surface and the cross section of the rod body, and the special-shaped rod body warps out of the three-jaw chuck.
8. The process for machining a three-dimensional special-shaped rod part according to claim 6, wherein in the step nine, the lathe fixture is used for forming the three-dimensional space positioning surface by linear cutting through a program for linear cutting of the part shape, so that the positioning surface of the fixture is attached to the part shape at high height, and the positioning precision is guaranteed.
9. The process for machining a three-dimensional special-shaped rod part according to claim 6, wherein in the ninth step, the lathe fixture is used for positioning the left end of the part in an axial direction, and the rod body perpendicular to the axial direction and the three-dimensional positioning surface is positioned by using two cylindrical pins.
10. The process for machining a three-dimensional special-shaped rod part according to claim 1, wherein a heat treatment step is further performed between the second step and the third step.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111238868.1A CN114154256A (en) | 2021-10-25 | 2021-10-25 | Machining process for three-dimensional special-shaped rod part |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111238868.1A CN114154256A (en) | 2021-10-25 | 2021-10-25 | Machining process for three-dimensional special-shaped rod part |
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| CN114154256A true CN114154256A (en) | 2022-03-08 |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030004596A1 (en) * | 2001-03-14 | 2003-01-02 | Landers Diane M. | Horizontally-structured CAD/CAM modeling for virtual concurrent product and process design |
| US20120076973A1 (en) * | 2008-04-17 | 2012-03-29 | The Boeing Company | Method and apparatus for producing contoured composite structures and structures produced thereby |
| CN207123974U (en) * | 2018-02-01 | 2018-03-20 | 杨庆 | A kind of combination unit of primary school mathematics several teaching |
| CN108127347A (en) * | 2017-12-27 | 2018-06-08 | 哈尔滨汽轮机厂有限责任公司 | Detect the blade specific processing method of technique segmental arc amount |
| WO2019170243A1 (en) * | 2018-03-08 | 2019-09-12 | Carl Zeiss Industrielle Messtechnik Gmbh | Method for quality assurance and/or quality improvement |
-
2021
- 2021-10-25 CN CN202111238868.1A patent/CN114154256A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20030004596A1 (en) * | 2001-03-14 | 2003-01-02 | Landers Diane M. | Horizontally-structured CAD/CAM modeling for virtual concurrent product and process design |
| US20120076973A1 (en) * | 2008-04-17 | 2012-03-29 | The Boeing Company | Method and apparatus for producing contoured composite structures and structures produced thereby |
| CN108127347A (en) * | 2017-12-27 | 2018-06-08 | 哈尔滨汽轮机厂有限责任公司 | Detect the blade specific processing method of technique segmental arc amount |
| CN207123974U (en) * | 2018-02-01 | 2018-03-20 | 杨庆 | A kind of combination unit of primary school mathematics several teaching |
| WO2019170243A1 (en) * | 2018-03-08 | 2019-09-12 | Carl Zeiss Industrielle Messtechnik Gmbh | Method for quality assurance and/or quality improvement |
Non-Patent Citations (2)
| Title |
|---|
| 张宏良: "烟气轮机动叶片叶身数控加工方法研究", 中国优秀硕士论文电子期刊网, 15 September 2014 (2014-09-15), pages 5 - 30 * |
| 曾艳 等: "面向数控加工的大型螺旋桨桨叶的余量估算问题研究", 中国机械工程, vol. 17, no. 06, 30 March 2006 (2006-03-30), pages 566 - 569 * |
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