CN110899527B - Necking device for cylindrical part - Google Patents
Necking device for cylindrical part Download PDFInfo
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- CN110899527B CN110899527B CN201911179615.4A CN201911179615A CN110899527B CN 110899527 B CN110899527 B CN 110899527B CN 201911179615 A CN201911179615 A CN 201911179615A CN 110899527 B CN110899527 B CN 110899527B
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- cylinder
- cylinder body
- necking
- piston rod
- clamping plate
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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
- B21D41/00—Application of procedures in order to alter the diameter of tube ends
- B21D41/04—Reducing; Closing
Abstract
The invention discloses a tubular piece necking device which comprises a double-acting telescopic cylinder, an anti-crease device, an upper necking die, a lower necking die and a necking driving device, wherein the upper necking die is used for containing the upper part of a tubular piece and is fixedly connected with a slide block of a press machine, the lower necking die is used for containing the lower part of the tubular piece and is fixedly connected with a workbench of the press machine, the double-acting telescopic cylinder comprises a first cylinder body, a second cylinder body and a piston rod, the piston rod sequentially penetrates through an upper clamping plate, an elastic ring and a lower clamping plate, when the piston rod moves upwards, the piston rod can drive the upper clamping plate and the lower clamping plate to clamp the elastic ring, the elastic ring is compressed to generate radial expansion, meanwhile, supporting force is generated on the inner wall of a necking of the tubular piece, when the necking driving device drives the upper necking die to be subjected to necking, the phenomenon of annular wrinkling is reduced, meanwhile, the single.
Description
Technical Field
The invention relates to the field of necking and reducing forming, in particular to a cylindrical piece necking device.
Background
The reducer pipe and the multi-way part are one of indispensable pipe fittings in various pipeline systems in the fields of aerospace, petroleum, chemical engineering and the like. Generally, a reducer pipe and a multi-way part are all integral components formed by a pipe blank through internal high pressure, the components are in axial and radial multi-way structures, and necking is a main forming process for forming a reducing part. Necking is a forming step of reducing the diameter of the mouth of a semi-closed cylindrical member, which has been drawn in advance, to a predetermined size by passing the semi-closed cylindrical member through a necking die.
At present, the method for necking the cylindrical part is mainly to realize spinning necking by radial feeding of a spinning wheel or axial feeding of a die for necking. After spinning and necking, spinning wheel marks are often left on the surface, particularly on softer materials such as aluminum alloy and the like; the direct necking of the die is affected by circumferential destabilization wrinkling of the cylindrical part, single necking deformation cannot be too large, multiple necking is needed, and heat treatment is needed between processes.
Therefore, there is a need in the art for a necking device that prevents circumferential wrinkling, increases the amount of single deformation, and reduces the number of necking operations.
Disclosure of Invention
The invention aims to provide a cylindrical piece necking device, which is used for solving the problems in the prior art, preventing annular wrinkling, improving single deformation and reducing necking times.
In order to achieve the purpose, the invention provides the following scheme:
the invention provides a tubular piece necking device, which comprises a double-acting telescopic cylinder, a crease-resist device, a necking upper die, a necking lower die and a press machine, wherein the necking upper die is used for containing the upper part of a tubular piece and is fixedly connected with a slide block of the press machine, the necking lower die is used for containing the lower part of the tubular piece and is fixedly connected with a workbench of the press machine, the double-acting telescopic cylinder comprises a first cylinder body, a second cylinder body and a piston rod, the second cylinder body is sleeved inside the first cylinder body, the inner wall of the second cylinder body is connected with a piston in a sliding way, the piston is fixedly connected with the piston rod, the crease-resist device comprises an upper clamping plate, a lower clamping plate and an elastic ring, the piston rod sequentially penetrates through the upper clamping plate, the elastic ring and the lower clamping plate, when the piston rod moves upwards, the piston rod can drive the upper clamping plate and the lower clamping plate to clamp the elastic ring, the elastic ring generates expansion deformation to generate supporting force on the inner wall of the necking of the cylindrical part, and the double-acting telescopic cylinder is in signal connection with a control device;
the double-acting telescopic cylinder is a double-acting hydraulic cylinder, an oil cylinder sleeve is sleeved outside the first cylinder body, and the oil cylinder sleeve is fixedly connected with a sliding block of the press machine; the hydraulic cylinder is characterized in that a first cylinder upper cavity liquid inlet is formed in the upper end of the first cylinder, a first cylinder lower cavity liquid inlet is formed in the lower end of the first cylinder, a second cylinder lower cavity liquid inlet channel is formed in the lower end of the second cylinder, an opening is formed in the upper end of the second cylinder, and hydraulic oil can enter the lower cavity of the second cylinder from the first cylinder lower cavity liquid inlet through the second cylinder lower cavity liquid inlet channel; when first cylinder body epicoele inlet oil feed, hydraulic oil can drive the piston rod is in the internal downstream of second cylinder, when first cylinder body cavity inlet oil feed, hydraulic oil can drive the piston rod is in upward movement in the second cylinder body.
Preferably, the upper end of the first cylinder body is provided with a first cylinder body upper end cover, the lower end of the first cylinder body is provided with a first cylinder body lower end cover, the first cylinder body lower end cover is fixedly connected with an oil cylinder fixing plate, and the oil cylinder sleeve and the necking upper die are fixedly connected with the oil cylinder fixing plate.
Preferably, a second cylinder end cover is fixedly arranged at the lower part of the second cylinder body, and a sealing ring is arranged at the joint of the second cylinder end cover and the second cylinder body.
Preferably, a sealing ring is arranged at the joint of the upper end cover of the first cylinder body and the first cylinder body, a sealing ring is arranged at the joint of the lower end cover of the first cylinder body and the first cylinder body, and a sealing ring is arranged on the contact surface of the piston and the second cylinder body.
Preferably, the piston rod passes through the upper clamping plate, the elastic ring and the lower clamping plate in sequence and then is fixedly connected with a fixing piece, and the fixing piece is used for limiting the downward movement of the lower clamping plate.
Preferably, the fixing member is a nut.
Preferably, the elastic ring is a polyurethane ring.
Compared with the prior art, the invention has the following beneficial technical effects:
the invention provides a tubular piece necking device which comprises a double-acting telescopic cylinder, an anti-crease device, an upper necking die, a lower necking die and a necking driving device, wherein the upper necking die is used for containing the upper part of a tubular piece and is fixedly connected with a slide block of a press machine, the lower necking die is used for containing the lower part of the tubular piece and is fixedly connected with a workbench of the press machine, the double-acting telescopic cylinder comprises a first cylinder body, a second cylinder body and a piston rod, the piston rod sequentially penetrates through an upper clamping plate, an elastic ring and a lower clamping plate, when the piston rod moves upwards, the piston rod can drive the upper clamping plate and the lower clamping plate to clamp the elastic ring, the elastic ring is compressed to generate radial expansion, meanwhile, supporting force is generated on the inner wall of a necking of the tubular piece, when the necking driving device drives the upper necking die to be subjected to necking, the phenomenon of annular wrinkling is reduced, meanwhile.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.
FIG. 1 is a schematic view of a cylindrical piece necking device according to the present invention;
in the figure: 1-necking down die, 2-cylindrical part, 3-nut, 4-lower clamping plate, 5-elastic ring, 6-upper clamping plate, 7-piston rod, 8-second cylinder, 9-piston, 10-cylinder fixing plate, 11-first cylinder, 12-cylinder sleeve, 13-first cylinder upper cavity liquid inlet, 14-first cylinder lower cavity liquid inlet, 15-second cylinder lower cavity liquid inlet channel, 16-necking down die, 17-first cylinder upper end cover, 18-first cylinder lower end cover, 19-second cylinder end cover.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
The invention aims to provide a cylindrical piece necking device to solve the problems in the prior art.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in further detail below.
The invention provides a tubular piece necking device, as shown in figure 1, comprising a double-acting telescopic cylinder, a crease-resist device, a necking upper die 16, a necking lower die 1 and a press machine, wherein the necking upper die 16 is used for containing the upper part of a tubular piece 2 and is fixedly connected with a slide block of the press machine, the necking lower die 1 is used for containing the lower part of the tubular piece 2 and is fixedly connected with a workbench of the press machine, the double-acting telescopic cylinder comprises a first cylinder body 11, a second cylinder body 8 and a piston rod 7, the second cylinder body 8 is sleeved in the first cylinder body 11, the inner wall of the second cylinder body 8 is connected with a piston 9 in a sliding manner, the piston 9 is fixedly connected with the piston rod 7, the crease-resist device comprises an upper clamping plate 6, a lower clamping plate 4 and an elastic ring 5, the piston rod 7 sequentially passes through the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4, when the piston rod 7 moves upwards, the piston rod 7 can drive the, the elastic ring 5 expands and deforms to generate supporting force on the inner wall of the necking of the cylindrical part 2, and the double-acting telescopic cylinder is in signal connection with the control device.
In the specific application process of the tubular piece necking device, firstly, a tubular piece 2 is fixed in a necking lower die 1, a press machine is started, a sliding block of the press machine drives a necking upper die 16 to move downwards, so that the tubular piece 2 enters the necking upper die 16 and moves until the lower surface of a lower clamping plate 4 is flush with the end face of a tubular opening of the tubular piece 2; then starting the double-acting telescopic cylinder to enable a piston rod 7 of the double-acting telescopic cylinder to drive the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 to move downwards until the upper surface of the elastic ring 5 is flush with the end face of the cylinder opening of the cylindrical part 2; then, the double-acting telescopic cylinder is started, so that the piston rod 7 drives the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 to move upwards, due to the limiting effect of the second cylinder end cover 19, the lower clamping plate 4 and the upper clamping plate 6 can clamp the elastic ring 5, the elastic ring 5 is compressed to expand, is completely attached to the inner wall of the cylindrical part 2 and generates a supporting force, at the moment, the press is started, so that a sliding block of the press drives the necking upper die 16 to move downwards, the second cylinder body 8 drives the lower clamping plate 4, the upper clamping plate 6 and the elastic ring 5 in a compressed state to synchronously continue to move upwards, the supporting force is ensured to act on a conical deformation area of the cylindrical part 2 all the time, and necking is gradually completed on the cylinder opening of the cylindrical part 2; after the necking, the double-acting telescopic cylinder releases pressure to enable the piston rod 7 to move downwards, the elastic ring 5 recovers elasticity, the sliding block of the press machine drives the necking upper die 16 to move upwards to obtain the tubular piece 2 after necking, when the tubular piece 2 is subjected to necking, the elastic ring 5 is adopted to elastically support the necking part, annular wrinkling is prevented when necking is avoided, single deformation is improved, and the necking times are reduced.
In this embodiment, the double-acting telescopic cylinder is a double-acting hydraulic cylinder, a cylinder sleeve 12 is sleeved outside the first cylinder body 11, and the cylinder sleeve 12 is fixedly connected with a slide block of the press; the upper end of the first cylinder body 11 is provided with a first cylinder body upper cavity inlet 13, the lower end of the first cylinder body 11 is provided with a first cylinder body lower cavity inlet 14, the lower end of the second cylinder body 8 is provided with a second cylinder body lower cavity inlet channel 15, the upper end of the second cylinder body 8 is provided with an opening, hydraulic oil can enter the lower cavity of the second cylinder body 8 from the first cylinder body lower cavity inlet 14 through the second cylinder body lower cavity inlet channel 15 and then flows into the upper cavity of the first cylinder body 11 through the opening, when oil is fed into the first cylinder body upper cavity inlet 13, the hydraulic oil can drive the piston rod 7 to move downwards in the second cylinder body 8, and when oil is fed into the first cylinder body lower cavity inlet 14, the hydraulic oil can drive the piston rod 7 to move upwards in the.
In a specific application process, the lower cavity of the first cylinder 11 is a cavity for accommodating the second cylinder 8, the upper cavity of the first cylinder 11 is a cavity for not accommodating the second cylinder 8, the lower cavity of the second cylinder 8 is a cavity for accommodating the piston rod 7, the upper cavity of the second cylinder 8 is a cavity for not accommodating the piston rod 7, and the second cylinder 8 in the double-acting hydraulic cylinder is a cylinder of the piston rod 7 and a piston of the first cylinder 11, so that the second cylinder 8 can move up and down in the first cylinder 11 under the pressure of hydraulic oil, and the piston rod 7 can move up and down in the second cylinder 8 under the pressure of hydraulic oil, and the hydraulic cylinders have the following characteristics: when the lower cavity of the cylinder body is filled with oil and the upper cavity of the cylinder body is filled with oil, the piston rod moves upwards, and when the upper cavity of the cylinder body is filled with oil and the lower cavity of the cylinder body is filled with oil, the piston rod moves downwards. When oil is fed from a liquid inlet 13 of the upper cavity of the first cylinder body and oil is discharged from a liquid inlet 14 of the lower cavity of the first cylinder body, a piston rod 7 of the second cylinder body 8 drives the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 to move downwards until the upper surface of the elastic ring 5 is flush with the end surface of the cylinder opening of the cylindrical part 2; the oil is fed into a liquid inlet 14 of the lower cavity of the first cylinder body, the oil enters the lower cavity of the second cylinder body 8 through a liquid inlet channel 15 of the lower cavity of the second cylinder body, so that the piston rod 7 drives the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 to move upwards, due to the limiting effect of the second cylinder end cover 19, the elastic ring 5 can be clamped by the lower clamping plate 4 and the upper clamping plate 6, and the elastic ring 5 is compressed to expand, is completely attached to the inner wall of the cylindrical part 2 and generates supporting force.
In this embodiment, in order to realize the sealing performance of the first cylinder 11, the upper end of the first cylinder 11 is provided with a first cylinder upper end cover 17, the lower end of the first cylinder 11 is provided with a first cylinder lower end cover 18, the first cylinder lower end cover 18 is fixedly connected with a cylinder fixing plate 10, both the cylinder sleeve 12 and the necking upper die 16 are fixedly connected with the cylinder fixing plate 10, and the cylinder sleeve 12 is fixedly connected with the necking upper die 16, so that the stability of the necking device is improved.
In this embodiment, a second cylinder end cover 19 is fixedly disposed at the lower portion of the second cylinder 8, and a sealing ring is disposed at a joint of the second cylinder end cover 19 and the second cylinder 8, so that the second cylinder 8 is sealed.
In this embodiment, a sealing ring is disposed at a joint of the first cylinder upper end cover 17 and the first cylinder 11, a sealing ring is disposed at a joint of the first cylinder lower end cover 18 and the first cylinder 11, and a sealing ring is disposed on a contact surface between the piston 9 and the second cylinder 8, so that the sealing performance of the double-acting hydraulic cylinder is improved, and oil leakage and pressure relief are prevented.
In this embodiment, lubricating oil is applied to the necking position where the necking upper die 16 contacts the cylindrical part 2, so that the friction force between the necking upper die 16 and the necking part of the cylindrical part 2 is reduced, and the necking effect is improved.
In this embodiment, in order to realize that the piston rod 7 can drive the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 to move integrally, the piston rod 7 passes through the upper clamping plate 6, the elastic ring 5 and the lower clamping plate 4 in sequence and then is fixedly connected with a fixing member, and the fixing member is used for limiting the downward movement of the lower clamping plate 4.
In this embodiment, in order to ensure that the connection stability of the fixing member and the piston rod 7 is improved, the fixing member is a nut 3.
In the present embodiment, in order to secure the elastic expansion performance of the elastic ring 5, the elastic ring 5 is a polyurethane ring.
The principle and the implementation mode of the invention are explained by applying specific examples, and the description of the above examples is only used for helping understanding the method and the core idea of the invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, the specific embodiments and the application range may be changed. In summary, this summary should not be construed to limit the present invention.
Claims (7)
1. A cylindrical piece necking device is characterized in that: including two effect telescoping cylinder, crease-resistance device, throat go up mould, throat lower mould and press, the throat go up the mould be used for holding the upper portion of section of thick bamboo and with the slider fixed connection of press, the throat lower mould be used for holding the lower part of section of thick bamboo and with the workstation fixed connection of press, two effect telescoping cylinder includes first cylinder body, second cylinder body and piston rod, the second cylinder body cover is established the inside of first cylinder body, the inner wall sliding connection of second cylinder body has a piston, the piston with piston rod fixed connection, the crease-resistance device includes grip block, lower grip block and elastic ring, the piston rod passes in proper order the grip block, the elastic ring with lower grip block, during the piston rod upward movement, the piston rod can drive the grip block with the grip block presss from both sides tightly the elastic ring down, the elastic ring generates expansion deformation to generate supporting force on the inner wall of the necking of the cylindrical part, and the double-acting telescopic cylinder is in signal connection with a control device;
the double-acting telescopic cylinder is a double-acting hydraulic cylinder, an oil cylinder sleeve is sleeved outside the first cylinder body, and the oil cylinder sleeve is fixedly connected with a sliding block of the press machine; the hydraulic cylinder is characterized in that a first cylinder upper cavity liquid inlet is formed in the upper end of the first cylinder, a first cylinder lower cavity liquid inlet is formed in the lower end of the first cylinder, a second cylinder lower cavity liquid inlet channel is formed in the lower end of the second cylinder, an opening is formed in the upper end of the second cylinder, and hydraulic oil can enter the lower cavity of the second cylinder from the first cylinder lower cavity liquid inlet through the second cylinder lower cavity liquid inlet channel; when first cylinder body epicoele inlet oil feed, hydraulic oil can drive the piston rod is in the internal downstream of second cylinder, when first cylinder body cavity inlet oil feed, hydraulic oil can drive the piston rod is in upward movement in the second cylinder body.
2. The cylinder necking apparatus of claim 1, wherein: the upper end of the first cylinder body is provided with a first cylinder body upper end cover, the lower end of the first cylinder body is provided with a first cylinder body lower end cover, the first cylinder body lower end cover is fixedly connected with an oil cylinder fixing plate, and the oil cylinder sleeve and the necking upper die are fixedly connected with the oil cylinder fixing plate.
3. The cylinder necking apparatus of claim 1, wherein: and a second cylinder end cover is fixedly arranged at the lower part of the second cylinder body, and a sealing ring is arranged at the joint of the second cylinder end cover and the second cylinder body.
4. The cylinder necking apparatus of claim 1, wherein: the sealing ring is arranged at the joint of the upper end cover of the first cylinder body and the first cylinder body, the sealing ring is arranged at the joint of the lower end cover of the first cylinder body and the first cylinder body, and the sealing ring is arranged on the contact surface of the piston and the second cylinder body.
5. The cylinder necking apparatus of claim 1, wherein: the piston rod penetrates through the upper clamping plate, the elastic ring and the lower clamping plate in sequence and then is fixedly connected with a fixing piece, and the fixing piece is used for limiting the downward movement of the lower clamping plate.
6. The cylinder necking apparatus of claim 5, wherein: the fixing piece is a nut.
7. The cylinder necking apparatus of claim 1, wherein: the elastic ring is a polyurethane ring.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911179615.4A CN110899527B (en) | 2019-11-27 | 2019-11-27 | Necking device for cylindrical part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911179615.4A CN110899527B (en) | 2019-11-27 | 2019-11-27 | Necking device for cylindrical part |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110899527A CN110899527A (en) | 2020-03-24 |
| CN110899527B true CN110899527B (en) | 2021-01-12 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911179615.4A Active CN110899527B (en) | 2019-11-27 | 2019-11-27 | Necking device for cylindrical part |
Country Status (1)
| Country | Link |
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| CN (1) | CN110899527B (en) |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU510296A1 (en) * | 1974-12-02 | 1976-04-15 | Предприятие П/Я В-2877 | Stamp for crimping hollow blanks |
| SU543448A1 (en) * | 1975-05-27 | 1977-01-25 | Crimping Tool | |
| SU664722A1 (en) * | 1977-05-10 | 1979-05-30 | Предприятие П/Я А-3813 | Die for compression of tubular blanks |
| SU804110A1 (en) * | 1979-03-29 | 1981-02-15 | Московский Авиационный Технологическийинститут Им.K.Э.Циолковского | Apparatus for reducing thin-walled tubes |
| JP3855789B2 (en) * | 2002-02-08 | 2006-12-13 | 東洋製罐株式会社 | Method and apparatus for reducing diameter of can body |
| DE60308515T2 (en) * | 2002-06-03 | 2007-01-18 | Novelis, Inc., Toronto | LINEAR DRIVE OF A FORMING MACHINE |
| CN103028655A (en) * | 2011-09-29 | 2013-04-10 | 郝俊峰 | Sealing and necking forming die |
| CN102601199A (en) * | 2012-02-29 | 2012-07-25 | 苏州经贸职业技术学院 | Precise-spin reducing device for fixed core type thin wall pipe |
| CN204148389U (en) * | 2014-07-30 | 2015-02-11 | 宁波金凌中德汽车部件有限公司 | Lining necking down frock |
| CN208146772U (en) * | 2018-04-28 | 2018-11-27 | 东莞市华茂电子集团有限公司 | A kind of necking die |
| CN109013937A (en) * | 2018-08-13 | 2018-12-18 | 宋丽 | A kind of reducing device of precompressed compact form automobile air-conditioning pipe processing |
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2019
- 2019-11-27 CN CN201911179615.4A patent/CN110899527B/en active Active
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