CN113118244B - High-strength aluminum alloy variable-section profile straightening method for aerospace and bridge - Google Patents
High-strength aluminum alloy variable-section profile straightening method for aerospace and bridge Download PDFInfo
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- CN113118244B CN113118244B CN202110426448.XA CN202110426448A CN113118244B CN 113118244 B CN113118244 B CN 113118244B CN 202110426448 A CN202110426448 A CN 202110426448A CN 113118244 B CN113118244 B CN 113118244B
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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
- B21D3/00—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
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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
- B21D3/00—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts
- B21D3/02—Straightening or restoring form of metal rods, metal tubes, metal profiles, or specific articles made therefrom, whether or not in combination with sheet metal parts by rollers
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Abstract
A method for straightening a high-strength aluminum alloy variable-section profile for spaceflight and bridges comprises the following steps: extruding to obtain a prefabricated variable cross-section profile, wherein the prefabricated variable cross-section profile comprises a large head area, a transition area and a profile area; straightening the big head area; carrying out transition pre-straightening on the transition area; then quenching and integral stretching and straightening are carried out; carrying out roller straightening on the section area; cutting off redundant parts of the section area and the large head area and then sizing; then local straightening is carried out to obtain the final product. According to the method, the pre-straightening is carried out in the big head area and the transition area, and then the quenching, stretching and straightening are carried out, so that the internal stress is greatly released, the production steps of the variable cross-section profile are simplified, and the quality of a final product is ensured.
Description
Technical Field
The application relates to a straightening method of a high-strength aluminum alloy variable-section profile for aerospace and bridges.
Background
The variable cross-section profile is generally used for transverse connecting structures such as wing trussed beams, bridges and the like of large transport airplanes and is a structural member for bearing load; high mechanical properties and dimensional accuracy are generally required. Therefore, the section 100mm before the joint (i.e. the transition zone) between the big end and the section is required to have high precision, and one big end causes the difficulty of straightening, stretching and finishing; if the roller cannot roll, the profile cannot be rolled in the area of 150mm in the transition area, and other corrective measures and technological methods are needed.
Disclosure of Invention
In order to solve the problems, the application provides a method for straightening a high-strength aluminum alloy variable-section profile for aerospace and bridges, which comprises the following steps:
extruding to obtain a prefabricated variable cross-section profile, wherein the prefabricated variable cross-section profile comprises a large head area, a transition area and a profile area;
straightening the big head area;
carrying out transition pre-straightening on the transition area;
then quenching and integral stretching and straightening are carried out;
carrying out roller straightening on the section area;
cutting off redundant parts of the section area and the large head area and then sizing;
then local straightening is carried out to obtain the final product. According to the method, the pre-straightening is carried out in the big head area and the transition area, and then the quenching, stretching and straightening are carried out, so that the internal stress is greatly released, the production steps of the variable cross-section profile are simplified, and the quality of a final product is ensured.
Preferably, the large head straightening is operated according to the following method: the method comprises the following steps of utilizing a vertical pressure straightener to straighten, arranging a supporting plate at the lower part of a transition area in the process of straightening large heads, arranging a shaping convex plate which is inserted into the transition area and is abutted against the inner surface of the transition area at the lower part of the transition area, and arranging the shaping convex plate in a matched manner with the vertical pressure straightener.
Preferably, the transition pre-straightening comprises a process of pressing the flaring or the closing of the transition area to a nominal size by using a vertical pressure straightening machine.
Preferably, the transitional pre-straightening further comprises the processes of planar flaring straightening and sidewall gap straightening; straightening the plane flaring within a range of 200mm extending from the transition area to the direction of the section part, and utilizing a spanner to pull up and down to finish the forming process; and the straightening of the side wall gap is a process of arranging an aluminum plate pad on the back of the bulge and then knocking the bulge part by using a knocking hammer.
Preferably, the roller straightening comprises flaring straightening and closing straightening, the flaring straightening comprises the steps of respectively arranging support cylinders on claw plates on two sides of the profile area, and then pressing the upper roller onto a bottom plate at the bottom of the profile area; the closing-in correction comprises the steps that a supporting column is arranged on a bottom plate at the bottom of the section area, then an upper roller is pressed into the bottom plate at the bottom of the section area, and the two sides of the upper roller are matched with the side walls of the section area.
Preferably, the roller straightening further comprises bend straightening, and the bend straightening further comprises knife bend straightening and upper and lower bend straightening; the knife-shaped bending correction comprises the process that one side wall of the section area is abutted with a bottom plate of the section area through a supporting plate, and then claw plates on the corresponding sides are abutted through upper rollers;
the upward and downward bending correction comprises the steps of abutting the bottom plate of the section area with a supporting plate, and then extruding and correcting the claw plates on two sides by utilizing the upper roller. The transition pre-straightening of the application comprises plane flaring straightening and side wall gap straightening, and the roller type straightening comprises primary treatment of a section area, wherein flaring straightening, closing correction and bending correction are carried out, the step is a continuous setting mode, most of defects and flaws can be basically treated, and a foundation is provided for subsequent local straightening.
Preferably, the local straightening comprises local flaring correction, local closing correction, upward and downward warping correction, claw plate wave bending correction and lateral bending correction.
Preferably, the partial flaring correction comprises the steps of arranging the profile area on a vertical pressure straightening machine, respectively arranging clamping blocks on claw plates on two sides of the profile area, and applying relative force to the clamping blocks by using the vertical pressure straightening machine; the local closing-in correction comprises the steps of arranging a profile area on a vertical pressure straightening machine, arranging a supporting plate on a bottom plate of the profile area, then arranging a wedge-shaped block on the upper part of an opening of the profile area, and then performing point pressing on the wedge-shaped block by using the vertical pressure straightening machine.
Preferably, the upward and downward tilting correction comprises the process of fixing the large head area by using a press machine, then carrying out claw plate sizing on the section area by using a wrench, and arranging an insert block at the corresponding position of the section area.
Preferably, the lateral bend correction comprises the process of fixing the large head area by using a press machine, fixing the section area by using a clamping piece, and then performing lateral extrusion; the clamping piece is a U-shaped piece which integrally wraps the section bar part or a U-shaped piece of which the middle part is provided with a clamping gap for clamping the claw plate. The local straightening of the application can reprocess local defect positions, and can obtain variable-section profiles meeting requirements on the premise of smaller local straightening work basically by means of good foundations of transition pre-straightening, stretching straightening and roller straightening before sizing.
This application can bring following beneficial effect:
1. the method has the advantages that the pre-straightening is carried out in the large head area and the transition area, and then the quenching, stretching and straightening are carried out, so that the internal stress is greatly released, the production steps of the variable cross-section profile are simplified, and the quality of a final product is ensured;
2. the transition pre-straightening comprises plane flaring straightening and side wall gap straightening, and the roller straightening comprises primary treatment of a profile area, namely flaring straightening, closing straightening and bending straightening;
3. the local straightening of the application can reprocess local defect positions, and can obtain variable-section profiles meeting requirements on the premise of smaller local straightening work basically by means of good foundations of transition pre-straightening, stretching straightening and roller straightening before sizing.
Drawings
The accompanying drawings, which are included to provide a further understanding of the application and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the application and together with the description serve to explain the application and not to limit the application. In the drawings:
FIG. 1 is a schematic structural diagram of the present application;
FIG. 2 is a schematic cross-sectional view of the large head region;
FIG. 3 is a schematic cross-sectional view of a profile section;
FIG. 4 is a schematic view of the large head being straightened;
FIG. 5 is a schematic view of a transition zone with a large head straightened;
FIG. 6 is a schematic view of a transition zone flare;
FIG. 7 is a schematic view of a transition zone closure;
FIG. 8 is a schematic view of the correction of the superior and inferior curves;
FIG. 9 is a schematic view of a knife bend correction;
FIG. 10 is a schematic view of partial flare correction;
figure 11 is a schematic view of a partial cuff correction;
FIG. 12 is a schematic view of a warp correction;
FIG. 13 is a schematic view of lateral bend correction;
FIG. 14 is a schematic view of a clamp during lateral bend correction;
figure 15 is a schematic view of a clamp during lateral bend correction.
Detailed Description
In order to clearly explain the technical features of the present invention, the present application will be explained in detail by the following embodiments in combination with the accompanying drawings.
As shown in the drawings, the following detailed description is given by way of example in order to more clearly explain the overall concept of the present application.
In addition, in the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like indicate orientations or positional relationships based on those shown in the drawings, merely for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be taken as limiting the present application.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments.
Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.
In this application, unless expressly stated or limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can include, for example, fixed connections, removable connections, or integral parts; the connection can be mechanical connection, electrical connection or communication; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.
In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through intervening media. In the description herein, reference to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the application. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
In a first embodiment, as shown in fig. 1-15, the present application discloses a method for straightening a high-strength aluminum alloy variable-section profile for aerospace and bridges, comprising the following steps:
s1, extruding to obtain a prefabricated variable cross-section profile, wherein the prefabricated variable cross-section profile comprises a large head area 1, a transition area 2 and a profile area 3;
s2, straightening the big head of the big head area 1;
the large head straightening is operated according to the following method: utilizing a vertical pressure straightener to straighten, arranging a supporting plate 5 at the lower part of the transition region 2 in the process of straightening the big end, arranging a shaping convex plate 4 which is inserted into the transition region 2 and is abutted against the inner surface of the transition region 2 at the lower part of the transition region 2, and arranging the shaping convex plate 4 in a matched manner with the vertical pressure straightener;
s3, performing transition pre-straightening on the transition region 2;
the transition pre-straightening comprises the process of extruding the flaring or closing of the transition area 2 to a nominal size by using a vertical pressure straightening machine; the transition pre-straightening also comprises the processes of plane flaring straightening and side wall gap straightening; the plane flaring straightening is within the range of 200mm extending from the transition area 2 to the direction of the section part, and a wrench 6 is used for carrying out up-and-down pulling to finish the forming process; the straightening of the side wall gap is a process of arranging an aluminum plate pad 7 on the back of the bulge and then knocking the bulge part by using a knocking hammer;
s4, quenching and integral stretching and straightening;
s5, carrying out roller straightening on the section area 3;
the roller straightening comprises flaring straightening and closing straightening, wherein the flaring straightening comprises the steps of respectively arranging support columns 9 on claw plates 8 on two sides of the profile area 3, and then pressing an upper roller 10 onto a bottom plate 11 at the bottom of the profile area 3; the closing correction comprises the steps that a support column 12 is arranged on a bottom plate 11 at the bottom of the section area 3, then an upper roller 10 is pressed onto the bottom plate 11 at the bottom of the section area 3, and two sides of the upper roller 10 are matched with side walls 13 of the section area 3; the roller straightening further comprises bending straightening, and the bending straightening further comprises knife-shaped bending straightening and upper and lower bending straightening; the knife-shaped bending correction comprises the process that one side wall 13 of the section area 3 is abutted with the bottom plate 11 of the section area 3 through the supporting plate 5, and then the claw plate 8 on the corresponding side is abutted through the upper roller 10; the upward and downward bending correction comprises the steps that a bottom plate 11 of the profile area 3 is abutted by a supporting plate 5, and then claw plates 8 on two sides are extruded and corrected by an upper roller 10;
s6, cutting off redundant parts of the section area 3 and the large head area 1, and then sizing;
s7, then carrying out local straightening to obtain a final product: the local straightening comprises local flaring correction, local closing correction, up-down warping correction, claw plate 8 wave bending correction and lateral bending correction. The local flaring correction comprises the steps that the profile area 3 is arranged on a vertical pressure straightening machine, clamping blocks 14 are respectively arranged on claw plates 8 on two sides of the profile area 3, and the vertical pressure straightening machine is utilized to apply relative force to the clamping blocks 14; the local closing-in correction comprises the steps of arranging a profile area 3 on a vertical pressure straightening machine, arranging a supporting plate 5 on a bottom plate 11 of the profile area 3, then arranging a wedge-shaped block 15 on the upper part of an opening of the profile area 3, and then performing point pressing on the wedge-shaped block 15 by using the vertical pressure straightening machine. The upward and downward warping correction comprises the process of fixing the large head area 1 by a press machine, then carrying out claw plate sizing on the section area 3 by a wrench 6, and arranging an embedding block 18 at the corresponding position of the section area. The lateral bend correction comprises the process of fixing the large head area 1 by a press machine, fixing the section area 3 by a clamping piece 16 and then laterally extruding; the clamping piece 16 is a U-shaped piece which integrally wraps the section bar part or a U-shaped piece of which the middle part is provided with a clamping gap 17 for clamping the claw plate 8.
The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, as for the system embodiment, since it is substantially similar to the method embodiment, the description is relatively simple, and reference may be made to the partial description of the method embodiment for relevant points.
The above are merely examples of the present application and are not intended to limit the present application. Various modifications and changes may occur to those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.
Claims (6)
1. A straightening method of a high-strength aluminum alloy variable-section profile for spaceflight and bridges is characterized by comprising the following steps of: the method comprises the following steps:
extruding to obtain a prefabricated variable cross-section profile, wherein the prefabricated variable cross-section profile comprises a large head area, a transition area and a profile area;
straightening the big head area;
carrying out transition pre-straightening on the transition area;
then quenching and integral stretching and straightening are carried out;
carrying out roller straightening on the section area;
cutting off redundant parts of the section area and the large head area and then sizing;
then carrying out local straightening to obtain a final product;
the transition pre-straightening comprises the process of extruding the flaring or closing of the transition area to the nominal size by using a vertical pressure straightening machine;
the transition pre-straightening also comprises the processes of plane flaring straightening and side wall gap straightening; the plane flaring straightening is within a range of 200mm extending from the transition area to the direction of the section part, and a wrench is used for pulling up and down to finish the forming process; the straightening of the side wall gap is a process of arranging an aluminum plate pad on the back of the bulge and then knocking the bulge part by using a knocking hammer;
the roller straightening comprises flaring straightening and closing straightening, wherein the flaring straightening comprises the steps of respectively arranging support cylinders on claw plates on two sides of a profile area, and then pressing an upper roller onto a bottom plate at the bottom of the profile area; the closing-in correction comprises the steps that a support column is arranged on a bottom plate at the bottom of a profile area, then an upper roller is pressed onto the bottom plate at the bottom of the profile area, and two sides of the upper roller are matched with the side wall of the profile area;
the roller straightening further comprises bending straightening, and the bending straightening further comprises knife-shaped bending straightening and upper and lower bending straightening; the knife-shaped bending correction comprises the process that one side wall of the section area is abutted with a bottom plate of the section area through a supporting plate, and then claw plates on the corresponding sides are abutted through upper rollers;
the upper and lower bending correction comprises the steps of abutting the bottom plate of the profile area with a supporting plate, and then extruding and correcting the claw plates on the two sides by utilizing the upper roller.
2. The method for straightening the high-strength aluminum alloy variable-section profile for the spaceflight and bridge according to claim 1, which is characterized by comprising the following steps of: the large head straightening is operated according to the following method: the method comprises the following steps of utilizing a vertical pressure straightener to straighten, arranging a supporting plate at the lower part of a transition area in the process of straightening large heads, arranging a shaping convex plate which is inserted into the transition area and is abutted against the inner surface of the transition area at the lower part of the transition area, and arranging the shaping convex plate in a matched manner with the vertical pressure straightener.
3. The straightening method of the high-strength aluminum alloy variable-section profile for spaceflight and bridges as claimed in claim 1, which is characterized in that: the local straightening comprises local flaring correction, local closing correction, up-down warping correction, claw plate wave bending correction and lateral bending correction.
4. The straightening method of the high-strength aluminum alloy variable-section profile for spaceflight and bridges as claimed in claim 3, which is characterized in that: the local flaring correction comprises the steps that a profile area is arranged on a vertical pressure straightening machine, clamping blocks are respectively arranged on claw plates on two sides of the profile area, and the vertical pressure straightening machine is utilized to apply relative force to the clamping blocks; the local closing-in correction comprises the steps of arranging a profile area on a vertical pressure straightening machine, arranging a supporting plate on a bottom plate of the profile area, then arranging a wedge-shaped block on the upper part of an opening of the profile area, and then performing point pressing on the wedge-shaped block by using the vertical pressure straightening machine.
5. The straightening method of the high-strength aluminum alloy variable-section profile for spaceflight and bridges as claimed in claim 3, which is characterized in that: the up-down tilting correction comprises the steps that a large head area is fixed through a press, then a spanner is used for shaping a claw plate in a section area, and an embedding block is arranged at the corresponding position of the section area.
6. The straightening method of the high-strength aluminum alloy variable-section profile for spaceflight and bridges as claimed in claim 3, which is characterized in that: the lateral bend correction comprises the process of fixing the large head area by using a press machine, fixing the section area by using a clamping piece and then performing lateral extrusion; the clamping piece is a U-shaped piece which integrally wraps the section bar part or a U-shaped piece of which the middle part is provided with a clamping gap for clamping the claw plate.
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| CN202110426448.XA CN113118244B (en) | 2021-04-20 | 2021-04-20 | High-strength aluminum alloy variable-section profile straightening method for aerospace and bridge |
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| CN202110426448.XA CN113118244B (en) | 2021-04-20 | 2021-04-20 | High-strength aluminum alloy variable-section profile straightening method for aerospace and bridge |
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| CN113118244B true CN113118244B (en) | 2023-03-21 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPH09285801A (en) * | 1996-04-25 | 1997-11-04 | Sumitomo Metal Ind Ltd | Method and equipment for manufacturing stainless steel shapes |
| CN105436249B (en) * | 2015-11-27 | 2017-09-29 | 攀钢集团攀枝花钢钒有限公司 | With the method for aligning of roll leveller straightening of kinked rail end |
| CN106513456B (en) * | 2016-11-16 | 2018-05-04 | 辽宁忠旺集团有限公司 | A kind of high-strength 2024 aluminium alloy thin-walled angle section production technology |
| CN107649530A (en) * | 2017-10-26 | 2018-02-02 | 西南铝业（集团）有限责任公司 | The production method and production equipment of space flight superelevation essence guide rail section |
| CN110129638B (en) * | 2019-05-10 | 2021-06-01 | 西北铝业有限责任公司 | Aluminum alloy multi-variable-section extruded section for aerospace and preparation method thereof |
| CN111604384A (en) * | 2020-05-13 | 2020-09-01 | 沈阳航空航天大学 | Preparation device and method for stage continuous extrusion gradient variable-section aluminum alloy section |
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