CN113579128A - Rolling process method of large aluminum alloy Y-shaped cross-section ring piece - Google Patents

Rolling process method of large aluminum alloy Y-shaped cross-section ring piece Download PDF

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Publication number
CN113579128A
CN113579128A CN202110861745.7A CN202110861745A CN113579128A CN 113579128 A CN113579128 A CN 113579128A CN 202110861745 A CN202110861745 A CN 202110861745A CN 113579128 A CN113579128 A CN 113579128A
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China
Prior art keywords
oblique angle
ring
flange
aluminum alloy
rolling
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CN202110861745.7A
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CN113579128B (en
Inventor
兰箭
华林
毛华杰
钱东升
邓加东
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Wuhan University of Technology WUT
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Wuhan University of Technology WUT
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21HMAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
    • B21H1/00Making articles shaped as bodies of revolution
    • B21H1/06Making articles shaped as bodies of revolution rings of restricted axial length
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21HMAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
    • B21H1/00Making articles shaped as bodies of revolution
    • B21H1/22Making articles shaped as bodies of revolution characterised by use of rolls having circumferentially varying profile ; Die-rolling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00Making machine elements
    • B21K1/76Making machine elements elements not mentioned in one of the preceding groups
    • B21K1/761Making machine elements elements not mentioned in one of the preceding groups rings

Abstract

The invention discloses a rolling process method of a large aluminum alloy ring with a fork-shaped section, which adopts a ring blank with a straight outer surface and a circumferential groove shape for being attached to a core roller, wherein a fork-shaped structure of the ring blank is placed downwards, the lower end surface of the fork-shaped structure is provided with an oblique angle, an adopted driving roller is in a straight shape, the outer surface of the core roller is matched with the inner surface of a designed ring forging, the core roller is provided with a flange, the upper end surface of the flange is provided with an oblique angle, the flange oblique angle can offset the axial offset load of the fork-shaped structure oblique angle, the outer edge of the bottom end of the flange oblique angle is lower than the plane of a workbench when the core roller is installed, the top end of the flange oblique angle is higher than the plane of the workbench, the fork-shaped structure oblique angle is contacted with the flange oblique angle, and a space formed by the flange oblique angle and the fork-shaped structure oblique angle enables the lower end of the outer edge of the ring blank to generate natural shrinkage in the rolling process, and the attachment length of the driving roller and the ring blank is reduced so as to reduce the required radial rolling force. The method can finish rolling the large aluminum alloy fork-shaped section ring piece by using the existing horizontal ring rolling mill, and has the advantages of simple process adjustment, easy use and good stability.

Description

Rolling process method of large aluminum alloy Y-shaped cross-section ring piece
Technical Field
The invention belongs to the field of metal material processing, and particularly relates to a rolling process method of a large aluminum alloy forked-section ring piece.
Background
The aluminum alloy Y-shaped cross-section ring piece is a very typical ring piece with a very complex cross-sectional shape, is widely used in the aerospace industry, and has a plurality of diameter size series, and the diameter size of 5m or more is difficult to manufacture due to more materials and large diameter-thickness ratio. At present, the manufacturing process of the aluminum alloy fork-shaped section ring piece is to roll the rectangular section ring piece and then carry out a large amount of subsequent machining to obtain the fork-shaped section ring piece, which not only wastes raw materials, but also greatly increases the manufacturing period.
In order to comply with the requirement of aerospace lightweight, the alloying degree of the novel aluminum-copper and aluminum-lithium alloy is improved, and the diameter of the alloy ingot is limited, so that the weight of the ingot which can be used for ring rolling is limited, the lightweight level of aerospace equipment and the diameter grade of the ring cannot be further improved, and the rolling of the ring with the special-shaped section is the only feasible way.
The existing horizontal ring rolling mill can just meet the rolling requirement of an original aluminum alloy rectangular-section ring forging with the diameter of 5 meters, the axial limit unbalance load of a core roller is smaller than 20 tons, but the special-shaped-section ring forging contains radial, axial and circumferential test blocks, the axial height of the original rectangular-section ring forging must be increased, and the rolling force requirement of the ring rolling mill is improved. Therefore, when large aluminum alloy forked section ring pieces are rolled on the existing horizontal ring rolling mill, the problems of insufficient rolling force, unstable rolling process, overlarge axial unbalance load and the like are faced.
Disclosure of Invention
The invention aims to provide a rolling process method of a large aluminum alloy forked cross-section ring piece, which aims at the problems of insufficient rolling force, unstable rolling process, overlarge axial unbalance load and the like of the existing horizontal ring rolling mill.
The technical scheme adopted by the invention is as follows:
a rolling process method for a large-scale aluminum alloy ring with a fork-shaped section comprises the steps that the outer surface of an adopted ring blank is flat, the inner surface of the adopted ring blank is provided with a circumferential groove type used for being attached to a core roller, a fork-shaped structure of the ring blank is placed downwards, the lower end face of the fork-shaped structure is provided with an oblique angle, an adopted driving roller is flat and straight, the outer surface of the core roller is matched with the inner surface of a designed ring forging, the core roller is provided with a flange, the upper end face of the flange is provided with an oblique angle, the flange oblique angle can offset axial unbalance loading of the fork-shaped structure oblique angle, the outer edge of the bottom end of the flange oblique angle is lower than a working platform plane when the core roller is installed, the top end of the flange oblique angle is higher than the working platform plane, the fork-shaped structure oblique angle is contacted with the flange oblique angle, and a space formed by the flange oblique angle and the fork-shaped structure oblique angle enables the ring blank to naturally draw and contract at the lower end of the outer edge in the rolling process, and the attachment length of the driving roller and the ring blank is reduced, so that required radial rolling force is reduced.
Further, assuming that the flange oblique angle is alpha, increasing alpha increases the requirement of radial rolling force, the increased radial rolling force needs to be smaller than the nominal radial rolling force of the horizontal ring rolling mill, and the maximum value of the radial rolling force and the maximum value of the axial rolling force are staggered in time of the rolling process, and the calculation formula of alpha is
Wherein, FmaxThe maximum axial load which can be borne by the connecting part of the core roll and the base of the horizontal ring rolling mill is P, and P is the radial rolling force required by the large aluminum alloy forked section ring piece.
Further, let the flange width be L, the calculation formula of L be
Wherein theta is a fork-shaped oblique angle FmaxThe maximum axial load borne by the connecting part of the core roller and the base of the horizontal ring rolling mill is P, the radial rolling force required by the large aluminum alloy forked section ring piece is L1Is a large aluminium alloy fork-shaped sectionTotal length of projection of the ring member in the axial direction, L2The axial projection length of a fork-shaped structure on the large aluminum alloy fork-shaped section ring piece is obtained.
Further, the fork-type structure bevel angle is 2-5 ° greater than the flange bevel angle.
Further, the circumferential groove depth of the inner surface of the ring blank is 30-50 mm.
Furthermore, the rolling feeding speed of the core roller is 0.1-0.6 mm/s.
Further, the processing method of the ring blank comprises the following steps: firstly, ingot casting, multidirectional upsetting, multi-directional upsetting, crushing, coarse phase refining and homogenizing grains, upsetting, punching and peeling to obtain an initial cake-shaped ring blank, then carrying out free forging saddle reaming to obtain a rectangular ring blank with the diameter as large as possible, then carrying out radial rolling and rounding to obtain a rectangular ring blank, and then machining the inner surface and the lower end face of the rectangular ring blank to obtain the required special-shaped cross section ring blank.
The invention has the beneficial effects that:
the method aims at the problems of insufficient rolling force, unstable rolling process, overlarge axial unbalance loading and the like of the existing horizontal ring rolling mill, the rolling production of the large aluminum alloy fork-shaped section ring piece can be completed by using the existing horizontal ring rolling mill by using the original straight driving roller and the core roller with the flange, the process is simple to adjust, the use is easy, and the stability is good.
Drawings
FIG. 1 is a schematic view of a large 2xxx series aluminum alloy fork-section ring forging in an embodiment of the invention.
FIG. 2 is a schematic view of the core roll of the horizontal ring rolling mill in the embodiment of the invention.
Fig. 3 is a schematic view of a ring blank with a profiled cross section in an embodiment of the invention.
FIG. 4 is a schematic view of the assembly relationship of the special-shaped section ring blank on the horizontal ring rolling mill when the rolling is started in the embodiment of the invention.
FIG. 5 is a diagram of an actual roll formed large 2xxx series aluminum alloy fork section ring forging.
Detailed Description
The invention is further described below with reference to the drawings and the examples.
Existing horizontal rollingThe maximum radial rolling force of the ring rolling mill is 300 tons, the maximum axial rolling force is 200 tons, and the axial bearing range of the core roller is +/-20 tons. The ring forging of the embodiment of the invention is shown in FIG. 1, and has an outer diameterThe maximum wall thickness is 175mm, the minimum wall thickness is 60mm, the overall axial height is 529mm, the axial height of a fork-shaped structure part is 207mm, the oblique angle of the fork-shaped structure is 28 degrees, and according to the volume of the ring forging shown in the figure 1, the required peeled ingot is obtained by considering the constant volume, the consumption in the middle blank making process and the quality of a 2xxx aluminum alloy ingotThe production process from the peeled cast ingot to the final large 2xxx series aluminum alloy fork-shaped section ring forging piece comprises the following steps of: 1) ingot casting multidirectional upsetting-pulling crushing coarse phase refining homogenizing grains; 2) upsetting, punching and peeling to obtain initial cake-shaped ring blank1555x300x530 mm; 3) free forging saddle reaming to obtain rectangular ring blank with diameter as large as possible3000x2600x552 mm; 4) radially rolling and rounding to obtain rectangular ring blank3200x2828x552 mm; 5) machining the inner surface and the lower end surface of the rectangular ring blank to obtain a ring blank with a special-shaped section; 6) and (4) loading the special-shaped section ring blank into a ring rolling mill to roll the special-shaped section ring blank into a large 2xxx series aluminum alloy forked section ring forging.
In the present embodiment, the calculation formula of the flange width L is:the oblique angle theta of the fork-shaped structure is 28 degrees, and the maximum axial load F borne by the connecting part of the core roll and the base of the horizontal ring rolling millmaxThe maximum radial rolling force of the horizontal ring rolling mill is 300 tons, and the radial rolling force required by the fork-shaped section ring piece is taken as the horizontal rolling ringThe maximum radial rolling force P of the machine is 300 tons, and the total length L of the projection of the fork-shaped section ring piece in the axial direction1529mm, the projection length L of the fork-shaped part of the fork-shaped section ring piece in the axial direction2207mm, obtainedTake L165 mm.
In the present embodiment, the flange inclination angle α is calculated by the formula:maximum axial load F capable of bearing connecting part of core roller and base of horizontal ring rolling millmaxThe maximum radial rolling force of the horizontal ring rolling mill is 300 tons at 20 tons, and the maximum axial load F is reachedmaxThe radial rolling force required by the ring piece with the cross-shaped section is staggered with the maximum radial rolling force of the horizontal ring rolling mill, and P is 250 tons to obtainTake α to 5 °.
In this embodiment, the flanged core roll is shown in fig. 2 in an axially vertical orientation, and the left end of fig. 2 is attached to the horizontal ring mill base work box in a manner and with a work box strength that allows only ± 20 tons of axial load, beyond which range core roll shifting or box crushing occurs. From the above calculation, the core roller had a flange width of 165mm and a maximum outer diameterThe upper end face of the flange is provided with a 5-degree inclined surface.
In this embodiment, the profiled ring blank is shown in fig. 3. The inner surface profile of the ring blank with the special-shaped section is similar to that of the ring forging of the embodiment shown in FIG. 1, the depth of the inner surface profile of the ring blank is 50mm, the lower end surface of the ring blank is provided with an inclined surface, namely a fork-shaped structure inclined angle, the inclined angle is 3 degrees larger than the corresponding flange inclined angle, and the inclined angle is 8 degrees.
In the embodiment, the special-shaped section ring blank is installed on a horizontal ring rolling mill to be rolled into a large 2xxx series aluminum alloy forked section ring forging. The schematic view of the assembly relationship of the special-shaped section ring blank on the horizontal ring rolling mill when rolling is started is shown in FIG. 4. The drive roller of the ring rolling mill is kept straight and does not need to be replaced, the axial position of the core roller with the flange is translated upwards to a position 25mm higher than the plane of the workbench, and the outer edge of the flange is an R60 round corner.
In the embodiment, the special-shaped section ring blank is hoisted and transferred to a position on a working table top of a horizontal ring rolling mill, which is as close to a driving roller as possible, then the core roller is rapidly fed towards the driving roller, through the matching of a flange inclined plane of the core roller and an inclined plane at the lower end of the special-shaped section ring blank, after the special-shaped section ring blank contacts the driving roller, the rolling feeding speed of the core roller is controlled to be 0.1-0.6 mm/s, and the rolling process is continuously carried out for 10-12 minutes until the preset outer diameter is reached5052 mm. The actual rolled large aluminum alloy Y-section ring is shown in FIG. 5.
It will be understood that modifications and variations can be made by persons skilled in the art in light of the above teachings and all such modifications and variations are intended to be included within the scope of the invention as defined in the appended claims.

Claims (7)

1. A rolling process method of a large aluminum alloy Y-shaped cross-section ring piece is characterized by comprising the following steps: the ring blank surface of adoption is straight, the internal surface has the circumference cell type that is used for laminating the core roller, the forked structure of ring blank is placed downwards and forked structure lower extreme mask has the oblique angle, the drive roller of adoption is straight shape, the core roller surface is coincide with design ring forging internal surface, the core roller has the flange and flange upper extreme mask has the oblique angle, the axial unbalance loading of forked structure oblique angle can be offset by the flange oblique angle, the bottom outer fringe of flange oblique angle is less than the workstation plane when the core roller is installed, the top is higher than the workstation plane, forked structure oblique angle contact is on the flange oblique angle, the space that flange oblique angle and forked structure oblique angle formed makes the ring blank produce the natural shrinkage at rolling in-process outer fringe lower extreme, thereby reduce the laminating length of drive roller and ring blank and reduce required radial rolling force.
2. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: setting the oblique angle of the flange as alpha, increasing alpha can increase the requirement of radial rolling force, the increased radial rolling force needs to be smaller than the nominal radial rolling force of the horizontal ring rolling mill, simultaneously, the maximum value of the radial rolling force and the maximum value of the axial rolling force are staggered in the time of the rolling process, and the calculation formula of alpha is
Wherein, FmaxThe maximum axial load which can be borne by the connecting part of the core roll and the base of the horizontal ring rolling mill is P, and P is the radial rolling force required by the large aluminum alloy forked section ring piece.
3. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: let the width of the flange be L, the calculation formula of L be
Wherein theta is a fork-shaped oblique angle FmaxThe maximum axial load borne by the connecting part of the core roller and the base of the horizontal ring rolling mill is P, the radial rolling force required by the large aluminum alloy forked section ring piece is L1Is the total length of the projection of the large aluminum alloy forked section ring piece in the axial direction, L2The axial projection length of a fork-shaped structure on the large aluminum alloy fork-shaped section ring piece is obtained.
4. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: the oblique angle of the fork-shaped structure is 2-5 degrees larger than that of the flange.
5. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: the circumferential groove depth of the inner surface of the ring blank is 30-50 mm.
6. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: the rolling feeding speed of the core roller is 0.1-0.6 mm/s.
7. The rolling process method of the large-scale aluminum alloy forked-section ring piece according to claim 1, characterized by comprising the following steps: the ring blank processing method comprises the steps of firstly carrying out ingot casting, multidirectional upsetting, multi-directional upsetting, crushing, coarse phase refining and homogenizing grains, then upsetting, punching and peeling to obtain an initial cake-shaped ring blank, then carrying out free forging trestle reaming to obtain a rectangular ring blank with the largest diameter, then carrying out radial rolling and rounding to obtain a rectangular ring blank, and then machining the inner surface and the lower end face of the rectangular ring blank to obtain the required special-shaped cross section ring blank.
CN202110861745.7A 2021-07-29 2021-07-29 Rolling process method of large aluminum alloy Y-shaped cross-section ring piece Active CN113579128B (en)

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Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU508320A1 (en) * 1973-04-09 1976-03-30 Ленинградское Конструкторское Бюротехнологического Оснащения A method of manufacturing ring de-hoists with a shaped outer surface
CN107931495A (en) * 2017-11-17 2018-04-20 武汉理工大学 A kind of cylindrical member it is each to deforming controllable enclosed roll former and method
CN108568489A (en) * 2018-03-30 2018-09-25 武汉理工大学 A kind of taper roll bearing outer ring precision cold-rolled manufacturing process
CN109482791A (en) * 2018-11-16 2019-03-19 贵州航天新力铸锻有限责任公司 A kind of C-shaped cross section ring centre embryo material preparation process
CN210450757U (en) * 2019-08-27 2020-05-05 张家港市亨通环形锻件制造有限公司 Die for manufacturing inner arc-shaped forge piece
CN111468653A (en) * 2020-04-15 2020-07-31 张家港海锅新能源装备股份有限公司 Ring rolling tool for producing bearing ring forge piece
CN211161700U (en) * 2019-11-27 2020-08-04 无锡隆迪精密锻件有限公司 Combined core roller for producing hub forging
CN213451964U (en) * 2020-10-23 2021-06-15 四川弘信能源装备制造有限公司 Blank before three-piece type ball valve cover forging is rolled
CN213645740U (en) * 2020-10-23 2021-07-09 四川弘信能源装备制造有限公司 Three-piece type flange ball valve cover rolling die

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
SU508320A1 (en) * 1973-04-09 1976-03-30 Ленинградское Конструкторское Бюротехнологического Оснащения A method of manufacturing ring de-hoists with a shaped outer surface
CN107931495A (en) * 2017-11-17 2018-04-20 武汉理工大学 A kind of cylindrical member it is each to deforming controllable enclosed roll former and method
CN108568489A (en) * 2018-03-30 2018-09-25 武汉理工大学 A kind of taper roll bearing outer ring precision cold-rolled manufacturing process
CN109482791A (en) * 2018-11-16 2019-03-19 贵州航天新力铸锻有限责任公司 A kind of C-shaped cross section ring centre embryo material preparation process
CN210450757U (en) * 2019-08-27 2020-05-05 张家港市亨通环形锻件制造有限公司 Die for manufacturing inner arc-shaped forge piece
CN211161700U (en) * 2019-11-27 2020-08-04 无锡隆迪精密锻件有限公司 Combined core roller for producing hub forging
CN111468653A (en) * 2020-04-15 2020-07-31 张家港海锅新能源装备股份有限公司 Ring rolling tool for producing bearing ring forge piece
CN213451964U (en) * 2020-10-23 2021-06-15 四川弘信能源装备制造有限公司 Blank before three-piece type ball valve cover forging is rolled
CN213645740U (en) * 2020-10-23 2021-07-09 四川弘信能源装备制造有限公司 Three-piece type flange ball valve cover rolling die

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