CN113333557B

CN113333557B - Flow spinning die for thin-wall cylinder section with crossed ribs and forming method thereof

Info

Publication number: CN113333557B
Application number: CN202110644862.8A
Authority: CN
Inventors: 于忠奇; 李淑慧; 赵亦希; 何霁; 余小鹏
Original assignee: Shanghai Jiaotong University
Current assignee: Shanghai Jiaotong University
Priority date: 2021-06-09
Filing date: 2021-06-09
Publication date: 2022-06-28
Anticipated expiration: 2041-06-09
Also published as: CN113333557A

Abstract

The invention relates to a flow spinning die for a thin-wall cylinder section with crossed ribs and a forming method thereof in the technical field of metal plastic processing, wherein the flow spinning die comprises a flange plate, a clamping ring, a mandrel, a section die, an end cover and a positioning plate; the flange plate and the end cover are respectively connected to the two axial ends of the mandrel, the outer diameters of the flange plate and the end cover are larger than the outer diameter of the mandrel, the clamping ring and the section die are sleeved on the outer peripheral surface of the mandrel, the section die is clamped between the clamping ring and the end cover, the other axial end of the clamping ring is in butt joint with the end surface of the flange plate, the other axial end of the end cover is connected with the positioning plate, and the outer peripheral surface of the positioning plate is higher than the outer peripheral surface of the section die. After the spinning is finished, the flange plate, the mandrel and the positioning plate are detached, and then the remaining clamping ring, the forming die, the end cover and the spinning-formed thin-wall cylinder section with the crossed ribs covering the forming die are placed into an aging furnace for heat treatment, so that the deformation of the thin-wall cylinder section with the crossed ribs in the process of manual aging is effectively reduced, and the purpose that a set of tool can be shared in the spinning and heat treatment is realized.

Description

Flow spinning die for thin-wall cylinder section with crossed ribs and forming method thereof

Technical Field

The invention relates to the technical field of metal plastic processing, in particular to a flow spinning die for a thin-wall cylinder section with crossed ribs and a forming method thereof.

Background

The thin-wall cylinder section with the crossed ribs is the first choice of the aerospace light-weight high-performance structural member due to the advantages of high rigidity, high strength, low structural weight coefficient and the like. For the integral manufacture of the thin-wall cylinder section with crossed ribs, the forming technology mainly adopted at present is a flow spinning process method. The integral manufacture process of the thin-wall cylinder section with the crossed ribs comprises two core procedures, namely, the thin-wall cylinder section with the crossed ribs is processed by flow spinning, and the mechanical property of the spun thin-wall cylinder section with the crossed ribs is strengthened by heat treatment. Due to the complex structure in the thin-wall cylinder section with the crossed ribs, the forming and the forming process are stripped by adopting the traditional flowing spinning-solid solution aging process, and the product form and position size is extremely easy to be out of tolerance due to heat treatment deformation in the actual processing process. At present, the problem of poor product form and position size caused by heat treatment deformation can be solved by adopting a solid solution state aluminum alloy spinning process route of 'tube blank solid solution-flow spinning-artificial aging'. However, due to the non-uniformity of spinning internal stress during the artificial aging process, the problems of out-of-tolerance of straightness and roundness of the thin-walled cylinder section with the crossed ribs still exist after the artificial aging process, and the artificial aging treatment in the mold is needed to further improve the dimensional precision.

The flow spinning die for the thin-wall cylinder with the crossed ribs has been developed. The document "Chinese invention patent with application publication number CN 109663680A" discloses a spinning forming die with longitudinal and transverse rib members and a design method. This solution has the following drawbacks: 1) the mould realizes the positioning of the ribbed groove core mould through the slide rail, and the core mould is separated from a workpiece when the base is disassembled after spinning, so that the mould can only be used for a tool during spinning forming and cannot be used for a tool during subsequent manual aging treatment. 2) The problem of high-efficiency disassembly of the tool in the flow spinning processing of the large thin-wall cylinder section with the crossed ribs is not considered.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a flow spinning die for a thin-wall cylinder section with crossed ribs and a forming method thereof.

The invention provides a flow spinning die for a thin-wall cylinder section with crossed ribs, which comprises a flange plate, a clamping ring, a mandrel, a section die, an end cover and a positioning plate;

the flange plate and the end cover are respectively connected to two axial ends of the mandrel, the outer diameters of the flange plate and the end cover are larger than that of the mandrel, the clamping ring and the section die are sleeved on the peripheral surface of the mandrel, the section die is clamped between the clamping ring and the end cover, the other axial end of the clamping ring is in butt joint with the end surface of the flange plate, the other axial end of the end cover is connected with the positioning plate, and the peripheral surface of the positioning plate is higher than that of the section die.

In some embodiments, the forming die is cut axially into a plurality of petals that are split circumferentially into the forming die.

In some embodiments, the petals include a first petal and a second petal, the cross section of the first petal is a quasi-rectangular, the cross section of the second petal is a quasi-trapezoid, the quasi-rectangular is a structure in which two side surfaces are parallel to each other and upper and lower end surfaces are arc surfaces, and the quasi-trapezoid is a structure in which two side surfaces are non-parallel surfaces and upper and lower end surfaces are arc surfaces.

In some embodiments, each said petal is provided with a separate criss-cross rib grid.

In some embodiments, the outer diameter of the clamping ring is greater than the outer diameter of the flange.

In some embodiments, the end of the flange plate connected with the mandrel is buckled with an adaptive L-shaped groove.

In some embodiments, the ends of the clamp ring that meet the swage are snap-fitted with mating L-shaped grooves.

In some embodiments, the end of the end cap that is connected to the swage is fastened by a matching L-shaped groove.

In some embodiments, the outer diameter of the end cap is smaller than the outer diameter of the die, and the groove between the die and the positioning plate is used for axially fixing the spinning blank.

The invention also provides a flow spinning forming method of the thin-wall cylinder section with the crossed ribs, which adopts the flow spinning die of the thin-wall cylinder section with the crossed ribs and comprises the following steps:

spinning: after the flange plate, the clamping ring, the mandrel, the section die and the end cover are assembled, a spinning blank is sleeved on the section die, then the positioning plate is tightly connected on the end cover, so that the spinning blank is clamped, and then the flow spinning die with the crossed rib thin-wall cylinder body with the spinning blank is tightly fixed on a machine tool through the flange plate to perform spinning operation;

and (3) artificial aging step: spinning and forming the thin-wall cylinder section with the crossed ribs through a spinning step, removing the flange plate, the mandrel and the positioning plate, and integrally feeding the remaining clamping ring, the forming die, the end cover and the thin-wall cylinder section with the crossed ribs covered on the forming die into an aging furnace for heat treatment;

demoulding: and demolding after the artificial aging step is finished.

Compared with the prior art, the invention has the following beneficial effects:

1. after the spinning is finished, the flange plate, the mandrel and the positioning plate are detached, and then the remaining clamping ring, the forming die, the end cover and the spinning-formed thin-wall cylinder section with the crossed ribs covering the forming die are placed into an aging furnace for heat treatment, so that the deformation of the thin-wall cylinder section with the crossed ribs in the process of manual aging is effectively reduced, and the purpose that a set of tool can be shared in the spinning and heat treatment is realized.

2. According to the invention, the flange plate is connected with the mandrel, the clamping ring is connected with the section mould, and the end cover is connected with the section mould in a buckling manner, so that the connected and assembled mould has better stability through a stepped structure on the whole.

3. According to the split-type structure forming die, the split-type structure of the forming die is optimized, the design of the crossed ribs on the split-type structure is further improved, the overall structural strength of the formed thin-wall cylinder section with the crossed ribs is improved, the demolding difficulty is reduced, meanwhile, the relative sliding between the split dies can be effectively prevented through the design of the split-type structure shape, and the structural strength of the spliced forming die is improved.

4. According to the invention, the outer diameter of the end cover is smaller than that of the section mould, so that a groove is formed between the section mould and the positioning plate, a limiting structure for limiting the axial displacement of the spinning blank is obtained, the function of the mould is enhanced, and the cost is reduced.

Drawings

Other features, objects and advantages of the invention will become more apparent upon reading of the detailed description of non-limiting embodiments with reference to the following drawings:

FIG. 1 is a schematic structural view of a flow spinning die for thin-walled cylinder sections with crossed ribs according to the present invention;

FIG. 2 is a cross-sectional view A-A of FIG. 1;

FIG. 3 is a schematic top view of the petals of the present invention;

FIG. 4 is a schematic view of the flange structure of the present invention;

FIG. 5 is a schematic view of the clamp ring structure of the present invention;

FIG. 6 is a schematic view of the end cap construction of the present invention;

FIG. 7 is a schematic view of a positioning plate according to the present invention;

FIG. 8 is a schematic view of the die structure under the aging condition of the invention.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that it would be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit of the invention. All falling within the scope of the present invention.

Example 1

The invention provides a flow spinning die with crossed rib cylinder sections, which comprises a flange plate 1, a clamping ring 2, a mandrel 3, a section die 4, an end cover 5 and a positioning plate 6, as shown in figures 1-8. The mandrel 3 is preferably a hollow shaft and is used for supporting the section mould 4, the section mould 4 is provided with reinforcing ribs 9 of crossed grids, the flange plate 1 and the end cover 5 are respectively and fixedly connected to the two axial ends of the mandrel 3 through the matching of screw holes and bolts, and the flange plate 1, the mandrel 3 and the end cover 5 are coaxial. The clamping ring 2 and the section mould 4 are sleeved on the outer peripheral surface of the mandrel 3, the section mould 4 is clamped between the clamping ring 2 and the end cover 5, wherein the outer diameter of the flange plate 1 is larger than that of the section mould 4, so that the other axial end surface of the clamping ring 2 can limit the clamping ring 2 in a manner of contacting with the end surface of the flange plate 1, and preferably, the outer diameter of the clamping ring 2 is larger than that of the flange plate 1 and that of the section mould 4. The positioning plate 6 is connected to the other axial end of the end cover 5, the positioning plate and the end cover can be fastened and connected through structural matching of screw holes and bolts, the peripheral surface of the positioning plate 6 is higher than the peripheral surface of the section mould 4, and therefore the spinning blank 7 is limited to move towards the direction of the positioning plate 6. The flange plate 1 can be detached together with the mandrel 3 and the positioning plate 6 after the spinning is finished, only the clamping ring 2, the section die 4, the end cover 5 and the spinning-formed thin-wall cylinder section 8 with the crossed ribs covering the section die 4 are left, and then the clamping ring 1, the section die 4, the end cover 5 and the spinning-formed thin-wall cylinder section with the crossed ribs are placed into an aging furnace for heat treatment during the artificial aging, so that the deformation of the thin-wall cylinder section with the crossed ribs in the artificial aging process is effectively reduced, and the purpose that a set of tool can be shared in the spinning and heat treatment is achieved.

Preferably, the end face of the flange plate 1 connected with the mandrel 3 is provided with an L-shaped groove, the L-shaped groove is arranged along the circumferential direction of the flange plate 1, correspondingly, the inner circumferential surface of the mandrel 3 is provided with a transverse L-shaped groove, and the mandrel 3 is fixedly connected with the flange plate 1 in a buckling manner. In the same optimization design, the connection mode of the end cover 5 and the section mould 4 and the butt joint of the clamping ring 2 and the section mould 4 are in buckled connection through the arranged matched L-shaped grooves. Through the buckling connection between the flange plate 1 and the mandrel 3, between the clamping ring 2 and the section die 4 and between the end cover 5 and the section die 4, the connected and assembled die integrally obtains better stability through a stepped structure.

Example 2

This embodiment 2 is formed on the basis of embodiment 1, and through optimizing the section mould to the components of a whole that can function independently structure to further to the design of cross muscle on the components of a whole that can function independently structure, improve the overall structure intensity of the thin-walled cylinder section of area cross muscle after the mould pressing takes shape, reduce the degree of difficulty of drawing of patterns, simultaneously through the design of components of a whole that can function independently structure shape, set up the lamella mould that the side inclination is different and splice, can effectively prevent the relative slip between the lamella mould, improve the structural strength of the section mould after the concatenation. Specifically, the method comprises the following steps:

as shown in fig. 1 to 8, a plurality of split molds 40 are spliced into a section mold 4 of an integral structure along the circumferential direction, and the two split molds 40 are basically free from gaps through process control. Preferably, the reinforcing rib grids on each petal 40 are independent, that is, the reinforcing rib grids on each petal 40 exist between two side faces of a single petal 40, but only one reinforcing rib grid is limited on each petal, and only the intersection points of the reinforcing rib grids need to be located in the boundaries of two adjacent petals 40, so that the overall structural strength of the molded cylinder section is improved. Further, the petal mould 40 mainly includes two kinds of structure formation, is first petal mould 401 and second petal mould 402 respectively, and wherein, first petal mould 401 is the similar rectangle structure, and second petal mould 402 is the similar trapezium structure, and the petal mould of two kinds constitutes holistic section mould 4 through the concatenation of circumference. The quasi-rectangular structure is a structure in which two side surfaces of a cross section of the first petal 401 are parallel to each other and upper and lower end surfaces are arc surfaces. The trapezoid-like structure is a structure in which two side surfaces of the cross section of the second petal 402 are non-parallel surfaces and upper and lower end surfaces are arc surfaces. The section mould design is for dividing the body structure, can reduce the degree of difficulty of drawing of patterns by a wide margin, simultaneously through setting up the different lamella moulds of side inclination and amalgamate, can effectively prevent the relative slip between the lamella mould, improves the structural strength of the section mould after the concatenation.

Example 3

Embodiment 3 is formed on the basis of

embodiment

1 or 2, and the outer diameter of the end cover is set to be smaller than the outer diameter of the die, so that a groove is formed between the die and the positioning plate, a limiting structure for limiting the axial displacement of the spinning blank is obtained, and the cost is reduced while the function of the die is enhanced. Specifically, the method comprises the following steps:

as shown in fig. 1-8, the outer diameter of the end cap 5 is smaller than the outer diameter of the die 4, after the die 4 is sleeved on the outer circumferential surface of the mandrel 3, the end surface of the die 4 is preferably connected with the end cap 5 in a snap fit manner through an adapted L-shaped groove, at this time, the outer diameter of the end cap 5 is designed to be smaller than the outer diameter of the die 4, after the positioning plate 6 is fixed on the other axial end of the end cap 5, a groove structure is formed between the die 4 and the positioning plate 6, after the spinning blank 7 is covered on the die 4, part of the spinning blank 7 is pressed into the groove, so as to form axial limit on the spinning blank 7, and prevent the blank from moving axially in the spinning process.

Example 4

This embodiment 4 is a flow-spinning forming method of a thin-walled cylinder section with intersecting ribs formed on the basis of embodiment 3, and the flow-spinning die of the cylinder section with intersecting ribs described in embodiment 3 is adopted, and includes a spinning step and an artificial aging step, as shown in fig. 1 to 8, where:

Spinning: when the flow spinning of the thin-wall cylinder section with the crossed ribs is carried out, a group of first split dies 401 and second split dies 402 are connected with a clamping ring 2 through positioning keys, other first split dies 401 and second split dies 402 are assembled in sequence, a mandrel 3 is inserted into a section die 4 and the clamping ring 2 in sequence, a flange plate 1 is fixed at the end part of the mandrel 3 through bolt connection, an end cover 5 is connected at the other axial end of the mandrel 3 and is in spinning lock joint with the end part of the section die 4, a blank 7 to be processed is sleeved on the section die 4, a positioning plate 6 is connected and fixed with the end cover 5 through bolts so as to clamp a spinning blank 7, and finally the flow spinning die of the thin-wall cylinder section with the crossed ribs is fastened on a machine tool through the flange plate 1 for spin forming.

Artificial aging step: through spinning, the thin-walled cylinder section 8 with the crossed ribs is molded, the flange plate 1, the mandrel 3 and the positioning plate 6 are removed, and the clamping ring 2, the section die 4, the end cover 5 and the formed thin-walled cylinder section 8 with the crossed ribs covered on the section die 4 are integrally conveyed into an aging furnace for heat treatment. Due to the supporting effect of the section die 4, the deformation of the thin-wall cylinder section 8 with the crossed ribs can be reduced in the artificial aging process. After the artificial aging working condition treatment is finished, the clamping ring 2, the end cover 5 and the split molds 40 of the combined forming mold 4 are disassembled, and the demolding of the thin-wall cylinder section 8 with the crossed ribs is finished.

In the description of the present application, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present application.

The foregoing description has described specific embodiments of the present invention. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention. The embodiments and features of the embodiments of the present application may be combined with each other arbitrarily without conflict.

Claims

1. A flow spinning die for a thin-wall cylinder section with crossed ribs is characterized by comprising a flange plate (1), a clamping ring (2), a mandrel (3), a forming die (4), an end cover (5) and a positioning plate (6);

The flange (1) and the end cover (5) are respectively connected to two axial ends of the mandrel (3), the outer diameters of the flange (1) and the end cover (5) are both larger than that of the mandrel (3), the clamping ring (2) and the section die (4) are sleeved on the outer peripheral surface of the mandrel (3), the section die (4) is clamped between the clamping ring (2) and the end cover (5), the other axial end of the clamping ring (2) is in butt joint with the end surface of the flange (1), the other axial end of the end cover (5) is connected with the positioning plate (6), and the outer peripheral surface of the positioning plate (6) is higher than that of the section die (4);

the outer diameter of the clamping ring (2) is larger than the outer diameter of the flange plate (1) and the outer diameter of the forming die (4) of the flange plate;

the outer diameter of the end cover (5) is smaller than that of the section mould (4), and a groove between the section mould (4) and the positioning plate (6) is used for axially fixing the spinning blank;

the flange plate (1) is fixedly connected to the end part of the mandrel (3) through bolts, and the end cover (5) is connected to the other axial end of the mandrel (3) and is buckled with the end part of the section mould (4);

The clamp ring (2) is limited when the flange plate (1) is connected with the mandrel (3), the flange plate (1) can be removed together with the mandrel (3) and the positioning plate (6) after the spinning is completed, only the clamp ring (2), the section die (4), the end cover (5) and the thin-wall cylinder section (8) with the crossed ribs, which is formed by spinning and covered on the section die (4), are left, and then the thin-wall cylinder section with the crossed ribs is put into an aging furnace for heat treatment during the artificial aging, so that the deformation of the thin-wall cylinder section with the crossed ribs in the artificial aging process is effectively reduced, and the purpose that one set of tool can be shared in the spinning and heat treatment is realized.

2. The thin-walled cylindrical segment flow spinning die with intersecting ribs as claimed in claim 1, characterized in that said forming die (4) is cut axially into a plurality of petals (40), and said petals (40) are split circumferentially to form said forming die (4).

3. The flow spinning die for the thin-wall cylinder section with the crossed ribs as recited in claim 2, wherein the petals (40) comprise a first petal (401) and a second petal (402), the cross section of the first petal (401) is a rectangle-like shape, the cross section of the second petal (402) is a trapezoid-like shape, the rectangle-like shape refers to a structure that two side faces are parallel to each other and upper and lower end faces are arc faces, and the trapezoid-like shape refers to a structure that two side faces are non-parallel faces and upper and lower end faces are arc faces.

4. The thin-walled cylindrical segment flow-spinning die with intersecting ribs as claimed in claim 2 or 3, wherein each said split die (40) is provided with independent criss-cross rib grids.

5. The flow spinning die for the thin-walled cylinder section with the crossed ribs as claimed in claim 1, wherein the end part of the flange plate (1) connected with the mandrel (3) is buckled through an adaptive L-shaped groove.

6. The flow spinning die for the thin-wall cylinder section with the crossed ribs as claimed in claim 1, wherein the end part of the clamping ring (2) connected with the section die (4) is buckled through an adaptive L-shaped groove.

7. The flow spinning die for the thin-walled cylinder section with the crossed ribs as claimed in claim 6, wherein the end part of the end cover (5) connected with the section die (4) is buckled through an adaptive L-shaped groove.

8. A flow spinning forming method for a thin-walled cylinder section with cross ribs, which is characterized in that the flow spinning die for the thin-walled cylinder section with the cross ribs as claimed in any one of claims 1 to 7 is adopted, and comprises the following steps:

spinning: after the flange plate (1), the clamping ring (2), the mandrel (3), the section die (4) and the end cover (5) are assembled, a spinning blank (7) is sleeved on the section die (4), then the positioning plate (6) is tightly connected on the end cover (5), so that the spinning blank (7) is clamped, and then the flow spinning die with the crossed rib thin-wall cylinder body and the spinning blank (7) is tightly fixed on a machine tool through the flange plate (1) to perform the operation;

Artificial aging step: spinning and forming a thin-walled cylinder section (8) with crossed ribs through a spinning step, removing the flange plate (1), the mandrel (3) and the positioning plate (6), and integrally feeding the remaining clamping ring (2), the forming die (4), the end cover (5) and the thin-walled cylinder section (8) with the crossed ribs covered on the forming die (4) into an aging furnace for heat treatment;

demoulding: and demolding after the artificial aging step is finished.