CN106825160A - The method for reducing bend pipe cross section distortion using magnetorheological packing material - Google Patents
The method for reducing bend pipe cross section distortion using magnetorheological packing material Download PDFInfo
- Publication number
- CN106825160A CN106825160A CN201611206101.XA CN201611206101A CN106825160A CN 106825160 A CN106825160 A CN 106825160A CN 201611206101 A CN201611206101 A CN 201611206101A CN 106825160 A CN106825160 A CN 106825160A
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- CN
- China
- Prior art keywords
- pipe fitting
- magnetorheological
- bending
- magnetorheological materials
- induction coil
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- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- 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
- B21D9/00—Bending tubes using mandrels or the like
- B21D9/08—Bending tubes using mandrels or the like in press brakes or between rams and anvils or abutments; Pliers with forming dies
-
- 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
- B21D9/00—Bending tubes using mandrels or the like
- B21D9/15—Bending tubes using mandrels or the like using filling material of indefinite shape, e.g. sand, plastic material
-
- 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
- B21D9/00—Bending tubes using mandrels or the like
- B21D9/16—Auxiliary equipment, e.g. machines for filling tubes with sand
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Bending Of Plates, Rods, And Pipes (AREA)
Abstract
A kind of method for being reduced bend pipe cross section distortion using magnetorheological packing material, is comprised the following steps：(1) tube intracavity to be bent is injected into magnetorheological materials, pipe fitting two ends are sealed with rubber stopper；(2) pipe fitting is put into the relevant position of bending mould；(3) induction coil for being fixed on pipe fitting side is powered and produces magnetic field, magneticaction is applied to pipe fitting deformed area, change the rheological behavior of magnetorheological materials in pipe fitting；(4) pipe fitting is bent, while adjusting size of current to change magnetic field intensity, the rheological behavior of real-time regulation magnetorheological materials；(5) after the completion of bending, turn off electric current and pipe fitting is taken out from bending mould；(6) rubber stopper at removal pipe fitting two ends, magnetorheological materials are poured out and concentrated on reclaim in special container.Various bent tube techniques such as the present invention is suitable for going for a stroll, bends, stretch bending, can reduce the cross section distortion of bend pipe, and easy to operate, and magnetic flow liquid can be with Reusability, low cost.
Description
Technical field
Reduce bend pipe section using magnetorheological packing material the invention belongs to metal forming field, more particularly to one kind
The method of distortion.
Background technology
Elbow member is, using extremely extensive class hollow material product, typically to be caused using certain plastic molding method
Straight tube blank bends and is plastically deformed and is obtained.So far, for difference the need for be developed and go for a stroll, bend, rolling
Various bending pipes methods such as curved, stretch bending, and widely apply in production practices.But because tubing has thin-walled, hollow spy
There is corresponding limitation in different structure type, existing bending method, particularly bending quality is difficult to meet in actual applications
The requirement of precise treatment.For example, in these bending methods, pipe usually occurs different type and degree when bending in deformed area
Forming defects, including cross section distortion (fasciation or ovalization), local collapse, inner side gauffer and outside cracking etc., deformation
It is especially serious during more small curvature radius bend.For the thin-walled tube bending of square equal cross-section form, also there is distortion
Etc. the defect of other forms.These forming defectses not only influence attractive in appearance, the reduction part accuracy of product, also result in tubular construction
Bearing capacity declines, and has a strong impact on its military service performance.
Section fasciation when pipe bends almost is present in all of bend pipe process.In order to reduce this cross section distortion, people
Propose various methods, mandrel or filling steel ball, sand filler are such as increased using reversible deformation mould type groove, pipe inside
Deng.But either these methods are extremely limited to improving the effect of bending sections distortion, or lose practicality because of operating difficulties
Value, or because caused by filler internal pressure increase be difficult to control to be easy to occur tube wall rupture.In a word, existing method is difficult to
Meet the requirement to pipe fitting precision form in putting into practice.
Magnetorheological materials (Magnetorheological material) are that rheological behavior can be sent out under additional magnetic fields
A kind of life new material jumpy, including magnetic flow liquid, magnetic rheology elastic body and the powder with ferromagnetic effects etc. it is many
Type.Wherein, magnetic flow liquid is the Newtonian liquid that can be flowed freely when being acted on without externally-applied magnetic field, but is made in high-intensity magnetic field
Under, magnetic flow liquid can be changed into semisolid even solid-state in moment (Millisecond) from liquid, and controllable yield strength is presented, and
And this change is reversible.The special nature having using magnetic flow liquid, has started to use it for including that automobile hinders at present
The quite varied field such as Buddhist nun's damping, bearing seal.The original state of magnetic rheology elastic body is solid elastomer, its yield strength
Same meeting instantaneous variation with the change of externally-applied magnetic field.
Flexible die forming is by gas, fluid (such as aqueous water or oil), resisting medium, solid polyurethane rubber and discrete
The different types of materials such as grain carry out the extraordinary plastic forming technique of bulging etc. to thin-wall part as transmission medium, can be with
Obtain common plate process for stamping and be difficult to the thin wall parts such as the bellows that shapes.But gas, water or oil, resisting medium, solid-state are gathered
The tradition power transmission medium such as urethane rubber and discrete particle, can only be suitable for a range of Sheet Metal Forming respectively, and general
Store-through is the problems such as sealing difficulty, power transmission effect difference.Due to the above-mentioned special nature that magnetorheological materials have, also occur in recent years
The research of the flexible die forming process such as sheet bulging, such as Chinese patent CN102615164A are applied to as transmission medium
(a kind of sheet material magnetic flow liquid flexible die forming device and method), a kind of CN103273644A (sheet materials based on magnetic rheology elastic body
Flexible die forming device and method), CN104874662A (special-shaped plate magnetic medium damping building mortion and method) etc..But these
Magnetic flow liquid/elastomer is applied to the main purpose of flexible die forming as transmission medium, is to solve traditional transmission medium to exist
Sealing is difficult, power transmission effect difference the problems such as.In addition, magnetorheological materials are not yet obtained in terms of other of sheet forming field
To application.
The content of the invention
The need for the present invention is for accurate bending tube forming, there is provided one kind reduces bend pipe section using magnetorheological packing material
The method of distortion.To achieve these goals, the present invention is comprised the following steps：
(1) tube intracavity to be bent is injected into magnetorheological materials, the two ends of pipe fitting are sealed with rubber stopper.The magnetic
Rheo-material can be magnetic flow liquid, and iron powder and steel ball with ferromagnetic effects；
(2) pipe fitting is put into the relevant position of bending mould；
(3) induction coil for being fixed on pipe fitting side is powered, the bending using the magnetic field of induction coil generation to pipe fitting
Deformed area applies magneticaction, changes the rheological behavior of inside pipe fitting magnetorheological materials；
(4) bending forming is carried out to pipe fitting using bending mould.While pipe fitting deforms, can be by adjusting induction coil
The size of interior electric current changes magnetic field intensity, the rheological behavior of magnetorheological materials in regulation pipe fitting, so that real-time control pipe fitting is curved
The internal pressure of bent deformed area, reaches the purpose of the distortion for farthest reducing pipe fitting deformed area section；
(5) after the completion of bending operation, the electric current by the induction coil is turned off, while pipe fitting is taken from bending mould
Go out；
(6) rubber stopper at removal pipe fitting two ends, in pouring out the magnetorheological materials of tube intracavity and concentrate on special container
Reclaimed.
The invention has the advantages that：Using magnetorheological materials as inner chamber during hollow pipe fitting bending forming filling
Body, support can be provided in bend pipe to deformed area, while when can also be deformed according to pipe fitting the need for powder injection molding, adjusting in real time
Save the rheology characteristic of internal magnetorheological materials, the intelligent control of pipe fitting internal pressure realized, so as to reduce the cross section distortion of pipe fitting
Deng forming defects, the need for meeting accurate bending tube forming.Further, since magnetorheological materials have very well in no magnetic fields
Mobility, therefore the operation such as the filling and removal of magnetorheological materials in pipe fitting, and magnetorheological materials can be conveniently realized
Can reclaim and Reusability, use cost is low.Polytype light-wall pipes such as the present invention is suitable for going for a stroll, stretch bending, press-bending are curved
Bent technique.
Brief description of the drawings
Below in conjunction with the accompanying drawings, the present invention is further illustrated.
During Fig. 1 is for the present invention, using the schematic diagram of magnetic flow liquid filling control pipe fitting rotary draw bending cross section distortion；
Fig. 2 is schematic diagram of the present invention using magnetic flow liquid filling control pipe fitting press shaping die cross section distortion；
Fig. 3 is the shape of cross section of pipe deformed area after the magnetic flow liquid filled tube bending forming of finite element modelling.
In Fig. 1 to Fig. 2,1-mould of going for a stroll, the tight insert of 2-die clamp of going for a stroll, 3-mould gripping block of going for a stroll, 4-induction coil,
5-pressure mould, 6-pipe fitting, 7-magnetic flow liquid, 8-rubber stopper, 9-wrinkle resistant piece, 10-bending die, 11-roller.
Specific embodiment
Separately below by pipe fitting (6) go for a stroll with as a example by press shaping die, to the present invention by the use of magnetorheological materials as filling
Internal pressure when the hollow pipe of media implementation shapes regulates and controls, is illustrated so as to reduce the method for bend pipe cross section distortion.
In two embodiments, the magnetic flow liquid (7) that the magnetorheological materials for using are mixed to get for iron powder and silicone oil, its Young
Modulus is 1500MPa.Induction coil (4) is DC coil, the excursion for being applied to the magnetic field intensity B of pipe fitting (6) is 0~
14000Gs, under different magnetic field intensity B the shear yield strength K excursions of corresponding magnetic flow liquid (7) be 0.003~
0.2MPa, the static friction coefficient μ between magnetic flow liquid (7) and pipe fitting (6) inwall with K linear changes, scope is 0.38~
0.5。
After pipe fitting (6) bending forming, the ovality Φ calculations of deformed area cross section are as follows：
Φ=(Dmax-Dmin)/Dmax× 100%
Dmax, DminThe oval major axis in the cross section in deformed area centre position and short axle respectively after pipe fitting (6) bending forming.
Embodiment 1 --- go for a stroll
The material of rotary draw bending tubing is the aluminium alloys of Al 6061, and external diameter is 18mm, and wall thickness is 2mm, density 2.89g/mm2,
Poisson's ratio v is 0.33, and Young's modulus is 68900MPa, and yield strength is 65MPa, and angle of bend is 90 °.
The step of bending forming, is as follows：
1. magnetic flow liquid (7), the rubber stopper of the two ends cylinder of pipe fitting (6) are injected into pipe fitting (6) inner chamber to be bent
(8) sealed；
2. pipe fitting (6) is put into rotary draw bending mould, that is, mould of going for a stroll (1), the tight insert of die clamp of going for a stroll (2), die clamp of going for a stroll
Tight relevant position between block (3), pressure mould (5) and wrinkle resistant piece (9)；
3. the direct current induction coil (4) for pair being fixed on pipe fitting (6) side is powered, and is produced using direct current induction coil (4)
Magnetic field applies magneticaction to the bending deformation area of pipe fitting (6), so as to change the rheological behavior of pipe inside magnetic flow liquid (7)；
4. bending forming operation is carried out to pipe fitting (6) using bending mould, while the electric current adjusted in induction coil (4) is big
It is small, by the rheological behavior for changing the internal magnetic flow liquid (7) of magnetic field intensity real-time control pipe fitting (6)；
5. after the completion of bending operation, pipe fitting (6) is taken out from bend pipe mould, turned off by the induction coil (4)
Electric current；
6. the rubber stopper (8) at pipe fitting (6) two ends is removed, the magnetic flow liquid (7) of pipe fitting (6) inner chamber is concentrated and is poured into special appearance
Device, reclaims to magnetic flow liquid (7).
Following table is go for a stroll radius respectively 70mm, the numerical simulation result of 40mm and 30mm.It can be seen that, it is not filled by magnetic flow liquid
(7) when, the ovality after pipe fitting (6) is gone for a stroll under three kinds of bending radius is respectively 12.08,16.93 and 20.18；Addition magnetic current
After becoming liquid (7), significantly declining occurs in ovality Φ, illustrate pipe fitting (6) go for a stroll after cross section distortion obtained effective control
System.
Embodiment 2 --- bend
The external diameter of pipe fitting (6) is 18mm, and wall thickness is 2mm, and material is 20 steel, density 7.85g/mm2, Poisson's ratio v is 0.3,
Young's modulus is 206000MPa, and yield strength is 275MPa, and angle of bend is 90 °.The step of bending forming, is the same.
Subordinate list is respectively the numerical simulation result of the press-bending of 70mm, 50mm and 30mm for bending radius.In table, K is magnetic current
Become liquid (7) correspondence magnetic field intensity under shear yield stress, μ be correspondence magnetic field intensity under magnetic flow liquid (7) and tube wall between
Static friction coefficient.
When being not filled by magnetic flow liquid (7), the ovality Φ that pipe fitting (6) bends under three kinds of bending radius is respectively 5.49,
7.93 and 14.01, and after adding magnetic flow liquid (7), ovality Φ declines, cross section distortion reduces.
Claims (3)
1. the method that a kind of magnetorheological packing material of utilization reduces bend pipe cross section distortion, it is characterised in that methods described is to pass through
What following steps were realized：
(1) tube intracavity to be bent is injected into magnetorheological materials, the two ends of pipe fitting are sealed with rubber stopper；
(2) pipe fitting is put into the relevant position of bending mould；
(3) induction coil for being fixed on pipe fitting side is powered, the flexural deformation using the magnetic field of induction coil generation to pipe fitting
Area applies magneticaction, changes the rheological behavior of inside pipe fitting magnetorheological materials；
(4) bending forming is carried out to pipe fitting using bending mould；
(5) after the completion of bending operation, the electric current by the induction coil is turned off, while pipe fitting is taken out from bending mould；
(6) rubber stopper at removal pipe fitting two ends, the magnetorheological materials of tube intracavity are poured out and concentrated on carry out in special container
Reclaim.
2. the method that the magnetorheological packing material of utilization as described in claim one reduces bend pipe cross section distortion, it is characterised in that：
The magnetorheological materials can be magnetic flow liquid, and iron powder and steel ball with ferromagnetic effects.
3. the method that the magnetorheological packing material of utilization as described in claim one reduces bend pipe cross section distortion, it is characterised in that：
While pipe fitting deforms, magnetic field intensity, magnetic current in regulation pipe fitting can be changed by adjusting the size of electric current in induction coil
Become the rheological behavior of material.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611206101.XA CN106825160A (en) | 2016-12-23 | 2016-12-23 | The method for reducing bend pipe cross section distortion using magnetorheological packing material |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611206101.XA CN106825160A (en) | 2016-12-23 | 2016-12-23 | The method for reducing bend pipe cross section distortion using magnetorheological packing material |
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| CN106825160A true CN106825160A (en) | 2017-06-13 |
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| CN201611206101.XA Pending CN106825160A (en) | 2016-12-23 | 2016-12-23 | The method for reducing bend pipe cross section distortion using magnetorheological packing material |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107520300A (en) * | 2017-07-18 | 2017-12-29 | 凌云工业股份有限公司 | A kind of inflation clamping device near closed hollow ring bumper bending forming |
| CN110340194A (en) * | 2019-08-20 | 2019-10-18 | 来安县浦创轨道装备有限公司 | A kind of bending heavy luggage erection is standby |
| JP2019211092A (en) * | 2018-05-31 | 2019-12-12 | 昭和電工株式会社 | Heat exchanger |
| CN111085833A (en) * | 2019-11-26 | 2020-05-01 | 重庆大学 | Method for controlling volume plastic forming distortion of bent hole by using local temperature difference |
| CN111940574A (en) * | 2020-07-08 | 2020-11-17 | 广东省工业设备安装有限公司 | Elbow cold bending device and method |
| CN112139318A (en) * | 2020-09-09 | 2020-12-29 | 南昌航空大学 | Titanium alloy bending die and machining method thereof |
| CN113414259A (en) * | 2021-06-23 | 2021-09-21 | 江苏理工学院 | Space S-bend anti-wrinkle process for large-size multilayer composite hollow pipe |
| CN115139497A (en) * | 2021-03-30 | 2022-10-04 | 南京航空航天大学 | Method for regulating and controlling machining quality of free bending pipe fitting by novel silicon rubber-based medium core |
| EP4316681A1 (en) * | 2022-08-04 | 2024-02-07 | MAHLE International GmbH | Method for producing a corrugated flat tube made of metal |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107520300A (en) * | 2017-07-18 | 2017-12-29 | 凌云工业股份有限公司 | A kind of inflation clamping device near closed hollow ring bumper bending forming |
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| CN110340194A (en) * | 2019-08-20 | 2019-10-18 | 来安县浦创轨道装备有限公司 | A kind of bending heavy luggage erection is standby |
| CN111085833A (en) * | 2019-11-26 | 2020-05-01 | 重庆大学 | Method for controlling volume plastic forming distortion of bent hole by using local temperature difference |
| CN111085833B (en) * | 2019-11-26 | 2022-04-29 | 重庆大学 | Method for controlling volume plastic forming distortion of bent hole by using local temperature difference |
| CN111940574A (en) * | 2020-07-08 | 2020-11-17 | 广东省工业设备安装有限公司 | Elbow cold bending device and method |
| CN111940574B (en) * | 2020-07-08 | 2022-03-04 | 广东省工业设备安装有限公司 | Elbow cold bending device and method |
| CN112139318A (en) * | 2020-09-09 | 2020-12-29 | 南昌航空大学 | Titanium alloy bending die and machining method thereof |
| CN115139497A (en) * | 2021-03-30 | 2022-10-04 | 南京航空航天大学 | Method for regulating and controlling machining quality of free bending pipe fitting by novel silicon rubber-based medium core |
| CN113414259A (en) * | 2021-06-23 | 2021-09-21 | 江苏理工学院 | Space S-bend anti-wrinkle process for large-size multilayer composite hollow pipe |
| CN113414259B (en) * | 2021-06-23 | 2022-08-16 | 江苏理工学院 | Space S-bend anti-wrinkle process for large-size multilayer composite hollow pipe |
| EP4316681A1 (en) * | 2022-08-04 | 2024-02-07 | MAHLE International GmbH | Method for producing a corrugated flat tube made of metal |
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Application publication date: 20170613 |