CN113579015A - Processing method of variable-thickness thin-wall component - Google Patents
Processing method of variable-thickness thin-wall component Download PDFInfo
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- CN113579015A CN113579015A CN202010362314.1A CN202010362314A CN113579015A CN 113579015 A CN113579015 A CN 113579015A CN 202010362314 A CN202010362314 A CN 202010362314A CN 113579015 A CN113579015 A CN 113579015A
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- padding
- thickness
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D5/00—Bending sheet metal along straight lines, e.g. to form simple curves
- B21D5/06—Bending sheet metal along straight lines, e.g. to form simple curves by drawing procedure making use of dies or forming-rollers, e.g. making profiles
- B21D5/08—Bending sheet metal along straight lines, e.g. to form simple curves by drawing procedure making use of dies or forming-rollers, e.g. making profiles making use of forming-rollers
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
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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
- G06F30/15—Vehicle, aircraft or watercraft design
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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
Abstract
The invention relates to the technical field of aircraft manufacturing, and discloses a method for processing a variable-thickness thin-wall component. The processing method of the variable-thickness thin-wall member comprises the following steps: processing the plate-shaped blank into an intermediate blank with a step-shaped section; calculating parameters, namely calculating discrete bending positions of the intermediate blank and the thickness of the padding at each bending position; processing the padding into strip padding with the thickness consistent with the calculation result; fixing the strip-shaped padding on the middle blank at a bending position corresponding to the thickness of the middle blank; and the bending die sequentially bends the bending positions of the middle blank fixed with the strip padding materials to form a workpiece. The processing method of the variable-thickness thin-wall member has high processing efficiency, saves padding materials and has high workpiece forming precision.
Description
Technical Field
The invention relates to the technical field of aircraft manufacturing, in particular to a method for processing a variable-thickness thin-wall component.
Background
The skin is an important structural part of an airplane, requires high strength and good plasticity of materials, also requires smooth surface and high corrosion resistance, and is a variable-thickness thin-wall component with certain curvature formed by processing a whole blank. In the traditional manufacturing method, the thickened thin plate member is usually formed by adopting a combined process of roll bending forming and chemical milling, but the chemical milling mode is gradually eliminated due to environmental unfriendliness, so that the forming method of the thickened thin-wall member is gradually improved to the direction of numerical control processing and press bending forming.
In the prior art, padding of a specific material is used for auxiliary processing during bending forming, namely, a whole piece of padding is covered and fixed on a blank with a step-shaped section so that the processed blank is in an equal-thickness state, and in the bending process, the padding transfers the force of a die to the blank, so that accurate bending forming is finally realized. The process of auxiliary bending of the padding is a coupling forming process of a multi-structure body, and the thickness, the material and the like of the padding can have certain influence on forming precision. In the prior art, a whole padding material is covered on a blank to be in an equal-thickness state, so that the padding material is wasted; on the other hand, the thickness of the padding at different bending positions is not easy to control, so that the forming precision of the workpiece is influenced.
Therefore, it is desirable to provide a method for processing a thin and thick member to solve the above problems.
Disclosure of Invention
The invention aims to provide a processing method of a variable-thickness thin-wall component, which can save padding and has high workpiece forming precision.
In order to achieve the purpose, the invention adopts the following technical scheme:
provided is a method for processing a variable-thickness thin-wall member, comprising the steps of:
processing the plate-shaped blank into an intermediate blank with a step-shaped section;
calculating parameters, namely calculating discrete bending positions of the intermediate blank and the thickness of the padding at each bending position;
processing the padding into strip padding with the thickness consistent with the calculation result;
fixing the strip-shaped padding on the middle blank at a bending position corresponding to the thickness of the middle blank;
and the bending die sequentially bends the bending positions of the middle blank fixed with the strip padding materials to form a workpiece.
Preferably, the bending die comprises an upper die, the upper die is a roller with a circular section, and the width of the strip-shaped padding is not larger than the diameter of the upper die.
Optionally, the length of the strip-shaped padding is the same as the length of the corresponding fixing position of the strip-shaped padding on the intermediate blank.
Optionally, the width of all the strip-shaped padding materials is uniform.
Optionally, in the calculating parameters step, the reference quantity includes a tolerance band of the workpiece and a size of the intermediate blank.
Optionally, the bending die comprises a lower die comprising two supports at a distance;
in the step of calculating the parameters, the step of calculating the reference quantity further includes a preset distance between the two supporting members.
Optionally, in the step of calculating parameters, the bending force to be applied by the bending die at each discrete bending position is calculated simultaneously.
Optionally, the material of the strip-shaped padding is 2024-O or nylon or rubber.
Optionally, the strip-shaped padding is fixed in a corresponding position of the intermediate blank by gluing.
Optionally, the intermediate blank is shaped by milling.
The invention has the beneficial effects that:
the processing method of the variable-thickness thin-wall component firstly calculates the discrete bending position of the intermediate blank 1 to be bent, and controls the bending position and the numerical control within a reasonable range, so that the bending can ensure the precision of the workpiece and improve the bending efficiency; meanwhile, the thickness of the padding required by each bending position is calculated, the padding is processed into a strip-shaped structure with corresponding thickness and then fixed at the corresponding bending position, the thickness of the padding at the position can be matched with the deformation amount required, the appropriate thickness of the padding at the bending position can be ensured, the bending precision is improved, the padding does not need to be fixed at the non-bending position, the using amount of the padding is saved, and the material cost is reduced. The processing method of the variable-thickness thin-wall member has high processing efficiency, saves padding materials and has high workpiece forming precision.
Drawings
FIG. 1 is a flow chart of a method of processing a thin-walled member with variable thickness according to an embodiment of the present invention;
FIG. 2 is a schematic structural view of an intermediate blank with a strip of dunnage secured thereto according to an embodiment of the present invention;
fig. 3 is a schematic view of a bending die for bending an intermediate blank with a strip of padding fixed thereto according to an embodiment of the present invention.
In the figure:
1-intermediate blank; 2-strip padding; 3, molding the die; and 4, lower die.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, removably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.
In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.
In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.
In the prior art, when a variable-thickness thin-wall member is processed by bending and forming, the padding needs to cover a blank with a step-shaped whole cross section, namely an intermediate blank, so as to change the intermediate blank into a state with equal thickness for bending, and on one hand, the padding is wasted; on the other hand, the thickness of the padding at different bending positions is not easy to control, so that the forming precision of the workpiece is influenced.
In view of the above problems, the present embodiment provides a method for processing a variable-thickness thin-wall member, which can be used in the technical field of aircraft manufacturing, and is particularly suitable for manufacturing a skin of an aircraft. As shown in fig. 1 to 3, the X direction is the thickness direction of the strip-shaped pad, the Y direction is the width direction of the strip-shaped pad, and the length direction of the strip-shaped pad is the direction perpendicular to both the X direction and the Y direction (i.e., the direction perpendicular to the paper). The method for processing the variable-thickness thin-wall component comprises the following steps of:
processing the plate-shaped blank into an intermediate blank 1 with a step-shaped section;
calculating parameters, namely calculating discrete bending positions of the intermediate blank 1 and the thickness of the padding at each bending position;
processing the padding into strip padding 2 with the thickness consistent with the calculation result;
fixing the strip-shaped padding 2 on the middle blank 1 at a bending position corresponding to the thickness of the middle blank;
the bending die sequentially bends the bending positions of the middle blank 1 fixed with the strip padding 2 to form a workpiece.
After a common plate-shaped blank is processed into an intermediate blank 1 with a step-shaped section, discrete bending positions at which the intermediate blank 1 needs to be bent are calculated, and the bending positions and the numerical control are controlled in a reasonable range, so that the precision of a workpiece can be ensured and the bending efficiency can be improved; meanwhile, the thickness of the padding required by each bending position is calculated, the padding is processed into a strip-shaped structure with corresponding thickness and then fixed at the corresponding bending position, the thickness of the padding at the position can be matched with the deformation amount required, the appropriate thickness of the padding at the bending position can be ensured, the bending precision is improved, the padding does not need to be fixed at the non-bending position, the using amount of the padding is saved, and the material cost is reduced. The processing method of the variable-thickness thin-wall member has high processing efficiency, saves padding materials and has high workpiece forming precision.
Specifically, in this embodiment, as shown in fig. 3, the bending die includes an upper die 3 and a lower die 4, where the upper die 3 is a roller with a circular cross section, the lower die 4 includes two supporting members, the two supporting members are of a columnar structure with a top end being an arc surface, and a distance between the two supporting members is adjustable. During operation, the intermediate blank 1 is placed between the upper die 3 and the lower die 4, the upper die rotates, a certain downward pressure is applied to the blank, and the two supporting pieces are matched, so that the blank is formed. And after the press bending of one press bending position is finished, lifting the upper die 3, driving the next press bending position of the intermediate blank 1 to the press bending die, and repeating the steps to finish the press bending of all the positions. Of course, in other embodiments, the bending die may also be a roller with a circular cross section as the upper die, and two rollers with a circular cross section as the lower die, and the distance between the two rollers of the lower die is adjustable. During operation, a blank is placed between the upper die and the lower die, the upper roller rotates and applies a certain downward pressure to the blank and is matched with the two lower rollers, so that the blank is formed, and the lower rollers rotate and can drive the blank to move to the next bending position.
The material properties, structural gaps and the like of the padding can affect the dimensional accuracy and surface quality of the workpiece, so the material of the strip-shaped padding 2 is 2024-O or nylon or rubber. These materials have good compression resistance and facilitate the transfer of the force of the press bending die to the intermediate blank 1, thus ensuring higher surface quality and dimensional accuracy of the final formed workpiece. Preferably, in this embodiment, the strip-shaped padding 2 is 2024-O, and the strength of the strip-shaped padding is closer to the strength of the workpiece material, so that the forming precision can be further improved. Further preferably, the strip-like padding 2 is fixed in position relative to the intermediate blank 1 by means of gluing. The strip-shaped packing material 2 is bonded on the middle blank 1, so that the contact surface between the strip-shaped packing material 2 and the middle blank 1 is uniform, the separation and the dislocation of the strip-shaped packing material 2 and the middle blank 1 can be avoided in the forming process, and the forming precision is further improved.
Preferably, the upper die 3 is a roll with a circular cross section, and the width of the strip-shaped padding 2 is not larger than the diameter of the upper die 3 of the bending die. In the process of pressing the middle blank 1 downwards by the upper die 3, the width of the effective deformation area is generally less than or equal to 20% of the diameter of the upper die 3, so that the width of the strip-shaped padding 2 is set to be not more than the diameter of the upper die 3 of the bending die, the strip-shaped padding 2 can be ensured to completely cover the deformation area, and the effect of reducing the consumption of the padding as much as possible can be achieved. Further, the width of the strip mat 2 in this embodiment is greater than 20% of the diameter of the upper die.
Further preferably, the widths of all strip-shaped packing materials 2 are the same, and when a plurality of strip-shaped packing materials are processed, if the thicknesses of the strip-shaped packing materials 2 required at different bending positions are the same, the widths are also set to be the same, and then the strip-shaped packing materials can be processed at the same time, so that the processing time is saved.
Optionally, the length of the strip-shaped padding 2 is the same as the length of the corresponding fixed position of the strip-shaped padding 2 on the workpiece. Namely, the strip-shaped padding material 2 is ensured to completely cover the intermediate blank 1 in the length direction.
Preferably, in the calculating parameters step, the calculation reference includes a tolerance band of the workpiece and a size of the intermediate blank 1. Parameters of the workpiece and parameters of the intermediate blank 1 are considered in the calculation model, so that more accurate bending position and padding thickness information of the corresponding position can be obtained. Further, in the step of calculating the parameters, the step of calculating the reference quantity further includes a preset distance between two supporting members of the lower die. The parameters of the die are added to the calculated factors at the same time, so that the forming precision of the final workpiece can be further improved.
In order to further improve the forming accuracy of the final workpiece, in the step of calculating parameters, the bending force that the bending die needs to apply at each discrete bending position is calculated simultaneously. Different bending positions respectively apply bending force matched with the deformation amount required by the positions, so that the forming precision of the whole workpiece can be improved.
In the actual processing process, before the bending die bends the intermediate blank 1 fixed with the strip-shaped padding 2, the lower die 4 is adjusted to the preset distance. The actual distance of the lower die is ensured to be consistent with the data used in the parameter calculation process, so that the machining precision is ensured.
Preferably, in this embodiment, the intermediate blank 1 is formed by milling. Namely, a platy blank is firstly milled into an intermediate blank 1 with a step-shaped section according to the shape of an actual workpiece, and then subsequent bending processing is carried out. The milling forming process is mature, and the processing efficiency is high.
The processing method of the variable-thickness thin-wall component comprises the following steps:
s1, milling the platy blank into an intermediate blank 1 with a step-shaped section;
s2, calculating parameters, calculating discrete bending positions of the intermediate blank 1, the thickness of the padding at each bending position and the bending force required to be applied by the bending die at each bending position according to the tolerance zone of the workpiece, the preset interval of the lower die 4 of the bending die and the size of the intermediate blank 1;
s3, processing the padding into strip-shaped padding 2 with the thickness consistent with the calculation result and the width equal to the calculation result;
s4, respectively adhering and fixing the strip-shaped padding materials 2 on the middle blank 1 at the bending positions corresponding to the thickness of the middle blank;
s5, adjusting the lower die 4 of the bending die to a preset distance and placing the intermediate blank 1 adhered with the strip-shaped padding 2 between the upper die 3 and the lower die 4;
s6, sequentially bending the bending positions of the middle blank 11 fixed with the strip-shaped padding 22 by the bending die to form a workpiece;
s7, the work is taken out, and the strip-shaped mat 2 is taken off.
It should be understood that the above-described embodiments of the present invention are merely examples for clearly illustrating the invention and are not to be construed as limitations of the embodiments of the present invention, but may be modified in various embodiments and applications by those skilled in the art according to the spirit of the present invention, and the content of the present description should not be construed as a limitation of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the claims of the present invention.
Claims (10)
1. A method for processing a variable-thickness thin-wall component is characterized by comprising the following steps:
processing the plate-shaped blank into an intermediate blank (1) with a step-shaped section;
calculating parameters, namely calculating discrete bending positions of the intermediate blank (1) and the thickness of the padding at each bending position;
processing the padding into strip-shaped padding (2) with the thickness consistent with the calculated result;
fixing the strip-shaped padding (2) on the middle blank (1) at a bending position corresponding to the thickness of the middle blank;
and the bending die sequentially bends the bending positions of the middle blank (1) fixed with the strip padding (2) to form a workpiece.
2. A method for manufacturing a thin-walled and variable-thickness member according to claim 1, wherein the bending die comprises an upper die (3), the upper die (3) is a roll with a circular cross section, and the strip-shaped pad (2) has a width not larger than the diameter of the upper die (3).
3. A method for manufacturing a thin-walled and variable-thickness member as claimed in claim 1 or 2, wherein the length of the strip-like mat (2) is the same as the length of the corresponding fixed position of the strip-like mat (2) on the intermediate blank.
4. A method of manufacturing a thin-walled and variable-thickness member as claimed in claim 1 or 2, wherein the strip-like mats (2) are all uniform in width.
5. A method of working a thin-walled member with a variable thickness according to claim 1 or 2, wherein in the step of calculating parameters, the reference quantity is calculated to include a tolerance band of the workpiece and a size of the intermediate blank (1).
6. A method of working a thin-walled, variable-thickness member according to claim 5, wherein the bending die comprises a lower die (4), the lower die (4) comprising two supports at a distance;
in the step of calculating the parameters, the step of calculating the reference quantity further includes a preset distance between the two supporting members.
7. The method of manufacturing a thin-walled member with a variable thickness according to claim 5, wherein the step of calculating parameters simultaneously calculates the bending force to be applied by the bending die at each discrete bending position.
8. A method for manufacturing a thin-walled member with a variable thickness as claimed in claim 1 or 2, wherein the material of the strip-shaped padding (2) is 2024-O or nylon or rubber.
9. A method for manufacturing a thin-walled and variable-thickness member as claimed in claim 1 or 2, wherein the strip-like padding (2) is fixed in the corresponding position of the intermediate blank (1) by gluing.
10. A method of machining a thin-walled, variable thickness component as claimed in claim 1, characterized in that the intermediate blank (1) is formed by milling.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202010362314.1A CN113579015B (en) | 2020-04-30 | 2020-04-30 | Processing method of variable-thickness thin-wall component |
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| CN202010362314.1A CN113579015B (en) | 2020-04-30 | 2020-04-30 | Processing method of variable-thickness thin-wall component |
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| CN113579015B CN113579015B (en) | 2022-12-06 |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU1794530C (en) * | 1990-12-17 | 1993-02-15 | Центральный научно-исследовательский институт технологии судостроения | Method for bending blank ends |
| US20090266135A1 (en) * | 2008-04-23 | 2009-10-29 | Benteler Automobiltechnik Gmbh | Method of producing sheet metal blanks having a varing thickness |
| CN102699653A (en) * | 2012-05-22 | 2012-10-03 | 大明重工有限公司 | Tailor-welding and bending method for multi-thick metal plate material |
| CN104138946A (en) * | 2014-06-27 | 2014-11-12 | 中国商用飞机有限责任公司 | Auxiliary padding bending and forming method for variable thickness thin-walled member |
| CN106881570A (en) * | 2017-03-17 | 2017-06-23 | 北京航星机器制造有限公司 | A kind of manufacture method of the circular arc with muscle covering |
| CN109866409A (en) * | 2017-12-05 | 2019-06-11 | 中国商用飞机有限责任公司 | A kind of manufacturing method of Varying-thickness covering |
-
2020
- 2020-04-30 CN CN202010362314.1A patent/CN113579015B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU1794530C (en) * | 1990-12-17 | 1993-02-15 | Центральный научно-исследовательский институт технологии судостроения | Method for bending blank ends |
| US20090266135A1 (en) * | 2008-04-23 | 2009-10-29 | Benteler Automobiltechnik Gmbh | Method of producing sheet metal blanks having a varing thickness |
| CN102699653A (en) * | 2012-05-22 | 2012-10-03 | 大明重工有限公司 | Tailor-welding and bending method for multi-thick metal plate material |
| CN104138946A (en) * | 2014-06-27 | 2014-11-12 | 中国商用飞机有限责任公司 | Auxiliary padding bending and forming method for variable thickness thin-walled member |
| CN106881570A (en) * | 2017-03-17 | 2017-06-23 | 北京航星机器制造有限公司 | A kind of manufacture method of the circular arc with muscle covering |
| CN109866409A (en) * | 2017-12-05 | 2019-06-11 | 中国商用飞机有限责任公司 | A kind of manufacturing method of Varying-thickness covering |
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| CN113579015B (en) | 2022-12-06 |
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