CN107737825B - A method of control large diameter thin wall aluminium alloy pipe buckle fold - Google Patents
A method of control large diameter thin wall aluminium alloy pipe buckle fold Download PDFInfo
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- CN107737825B CN107737825B CN201711031986.9A CN201711031986A CN107737825B CN 107737825 B CN107737825 B CN 107737825B CN 201711031986 A CN201711031986 A CN 201711031986A CN 107737825 B CN107737825 B CN 107737825B
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- tubing
- straight line
- bending
- aluminium alloy
- large diameter
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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
- 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
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
-
- 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
- B21D9/16—Auxiliary equipment, e.g. machines for filling tubes with sand
- B21D9/18—Auxiliary equipment, e.g. machines for filling tubes with sand for heating or cooling of bends
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Bending Of Plates, Rods, And Pipes (AREA)
Abstract
The present invention relates to a kind of methods for controlling large diameter thin wall aluminium alloy pipe buckle fold, it is specifically designed a kind of method for being bent produced fold applied to control in aluminium alloy large diameter thin wall pipe bending process, its be applicable to hope for success tubing inner cavity and outer wall surface after shape carries out fluorescent penetrant inspection without face crack, welding bead is without cracking, and part fold maximum is no more than the thin-wall pipes bending process of 10mm after being bent, the major diameter refers to that the diameter of tubing is 200-500mm, the thin-walled refers to that the wall thickness of tubing is 3-6mm, bending angle when bending pipes is not more than 60 °.The large diameter thin wall aluminium alloy pipe prepared using this method, it is smooth to effectively improve inner cavity, outer wall, reduces cracking caused by bending, snaps, reduces crimp height after bending, avoid the generation that can not repair fold, improve curved qualification rate.
Description
Technical field
The present invention relates to a kind of methods for controlling large diameter thin wall aluminium alloy pipe buckle fold, are specifically designed a kind of application
The method of fold produced by control is bent in aluminium alloy large diameter thin wall pipe bending process, it is applicable to hope for success after shape and manages
Material inner cavity and outer wall surface carry out fluorescent penetrant inspection, and without face crack, welding bead, without cracking, and after bending, part fold is maximum
Thin-wall pipes bending process no more than 10mm, the major diameter refer to that the diameter of tubing is 200-500mm, the thin-walled
The wall thickness for referring to tubing is 3-6mm, and bending angle when bending pipes is not more than 60 °.
Background technique
Often there is defect in processing when carrying out bending process in aluminium alloy large diameter thin wall pipe.Traditional press machine
The frequent cracked and serious fold of the curved contour forming method of fit circular arc face pressure, in some instances it may even be possible to weld seam occur or cylinder ontology is opened
It splits, the size and external form after forming tubular product are difficult to control；And filling liquid stretch bending manufacturing process is more suitable for narrow tube, and
Requirement to equipment and tubing intensity itself is relatively high, is not suitable for forming said alloy large diameter thin wall pipe.It is, thus, sought for
A kind of satisfactory for the curved reliable method of large diameter thin wall aluminium alloy pipe, the operation that can reduce forming tubular product is wanted
Summation device demand also can guarantee the forming quality of part.
Summary of the invention
Technology of the invention solves the problems, such as: overcome the deficiencies in the prior art, proposes that a kind of control large diameter thin wall aluminium closes
The method of golden bending pipes fold, this method can be applied to control bending pleat in aluminium alloy large diameter thin wall pipe bending process
Wrinkle is formed and deformation extent, in aluminum alloy thin-wall tube bending, can effectively improve that inner cavity, outer wall are smooth, and reducing bending causes
Cracking, snap, reduce bending after crimp height, avoid the generation that can not repair fold.
Technical Solving of the invention is:
A method of control large diameter thin wall aluminium alloy pipe buckle fold, the step of this method include:
(1) it calculates the volume V of filler and prepares filler；
(2) cavity plate is prepared；
(3) one end of tubing is blocked；
(4) step (1) ready filler is heated；
(5) filler heated in step (4) is circulated into the tubing for carrying out one end sealing end in step (3), then
Natural cooling；
(6) tubing that step (5) encapsulating has filler is placed on the cavity plate prepared in step (2)；
(7) tubing is bent, the tubing after being bent.
In the step (1), the volume of filler is consistent with the volume inside tubing, the volume V=π (D/ of filler
2)2L；D is the internal diameter of tubing, and L is the length of tubing.
In the step (1), filler includes rosin and building sand, and the mass ratio of rosin and building sand is 2.4:
1。
In the step (2), the cavity plate is rotate with a special-shaped figure, and special-shaped figure is axial symmetry
Figure.
Special-shaped figure surrounds a closed figure by three straight lines and an abnormal-shaped curve, three straight lines be respectively straight line a,
Straight line b and straight line c, the two straight line a and straight line b connecting with abnormal-shaped curve are parallel to each other, straight line c and this two parallel to each other
Straight line a and straight line b are vertical；Wherein, the abnormal-shaped curve is formed by three sections of circular arc continuous transitions, the curvature half of the circular arc of two sides
Diameter is mutually all r1, and the radius of curvature of intermediate circular arc is r2, and r2 is greater than r1.
The cavity plate is rotate using straight line d as axis, straight line d be the straight line parallel with straight line c and straight line d with
Central point, that is, minimum point distance of abnormal-shaped curve is r.
In the step (4), heating temperature is 125-135 DEG C.
In the step (6), the plane and press-bending that require central axis-tubing welding bead of tubing to be formed when placing tubing
The acute angle in equipment actuation direction is not less than 70 degree.
In the step (7), bends time-division multi-pass and carry out, when bending angle Ф is at 15 degree or less, divide 2-3 passage
It uniformly bends, when bending angle Ф is when 15-45 is spent, 4-7 passage should be divided, bending angle Ф is at least needed at 45 degree or more
It bends 9 times.
In the step (7), according to the radius R of the Inner arc of tubing theory external form after bending before bending, calculates and bend
The inner circle arc length of deformation section, then corresponding deformation position with line segment marks corresponding length on tubing, then will mark
Line segment bend number according to design and draw multistage line segment, each line segment endpoint is as cavity plate and tubing contact point, when pressurization
The contact point of successive adjustment cavity plate and tubing makes tubing homogeneous deformation.
In press bending process, cavity plate is 300-400mm at a distance from the contact point of tubing and pressure head middle line；
The soft rubber pad of anti-scratch is placed on the pressure head and cavity plate of the press bending apparatus, soft rubber mat thickness is 10-
15mm。
Beneficial effect
(1) the radius of curvature r2 of the intermediate circular arc of abnormal-shaped curve of the invention is bigger than two sides circular arc r1 so that tubing with
The contact of working curved surface faster, reduces the generation of fold；
(2) radius of turn r is 3%-7% smaller than the Inner arc R radius of Theoretical Design bending tubing, to reduce rebound to last
The influence of forming dimension；It is placed with soft rubber pad on the pressure head and cavity plate of press bending apparatus, with anti-scratch；
(3) using the large diameter thin wall aluminium alloy pipe of this method preparation, it is smooth to effectively improve inner cavity, outer wall, reduces
Cracking caused by bending snaps, and reduces crimp height after bending, avoids the generation that can not repair fold, improve curved qualification rate.
Detailed description of the invention
Fig. 1 is that tubing is placed in the structural schematic diagram on cavity plate；
Fig. 2 is the structural schematic diagram of cavity plate；
Fig. 3 is the label schematic diagram of deformation section.
Specific embodiment
A method of control large diameter thin wall aluminium alloy pipe buckle fold, the step of this method include:
(1) it calculates the volume V of filler and prepares filler；
The volume of the filler is consistent with the volume inside tubing, i.e. V=π (D/2)2L；D is the diameter of tubing, L
For the length of tubing；
The filler includes rosin and building sand, and the mass ratio of rosin and building sand is 2.4:1；
(2) cavity plate is prepared；
The cavity plate is rotate with a special-shaped figure；
The special-shaped figure is zhou duicheng tuxing, surrounds a closed figure by three straight lines and an abnormal-shaped curve,
Three straight lines are respectively straight line a, straight line b and straight line c, and the two straight line a and straight line b connecting with abnormal-shaped curve are parallel to each other, directly
Line c is vertical with two straight line a parallel to each other and straight line b；Wherein, the abnormal-shaped curve is by three sections of circular arc continuous transition shapes
At the radius of curvature of the circular arc of two sides is mutually all r1, and the radius of curvature of intermediate circular arc is r2, and r2 is greater than r1；
The cavity plate is rotate using straight line d as axis, straight line d be the straight line parallel with straight line c and straight line d with
Central point, that is, minimum point distance of abnormal-shaped curve is r；
Abnormal-shaped curve is working curved surface by the curved surface that rotation is formed；
(3) it is blocked using the one end of end socket to tubing；
(4) step (1) ready filler is heated, heating temperature is 125-135 DEG C；
(5) filler heated in step (4) is circulated into the tubing for carrying out one end sealing end in step (3), then
Natural cooling；
(6) tubing that step (5) encapsulating has filler is placed on the cavity plate prepared in step (2), and tubing with it is recessed
The working curved surface of mould is in contact；The plane and press bending apparatus actuation for requiring central axis-tubing welding bead of tubing to be formed when placement
The acute angle in direction is not less than 70 degree；
(7) tubing is bent, bends time-division multi-pass and carry out, when bending angle Ф is at 15 degree or less, divides the road 2-3
Secondary uniform press-bending should divide 4-7 passage, bending angle Ф is at least needed at 45 degree or more when bending angle Ф is when 15-45 is spent
It bends 9 times；
Inner arc (radius of Inner arc the is R) length for bending deformation section is calculated before bending, then to strain on tubing
Shaped position marks corresponding length with line segment, and the tubing label of this segment length is segmented into (required press-bending passage+1) section later,
As cavity plate and tubing contact point, contact point should be adjusted after pressurization every time；
In press bending process, cavity plate is 300-400mm at a distance from the contact point of tubing and pressure head middle line；
The soft rubber pad of anti-scratch is placed on the pressure head and cavity plate of the press bending apparatus, soft rubber mat thickness is 10-
15mm；
(8) it bends after receiving, removes the filler and end socket in tubing, and clear up tube surfaces, the pipe after being bent
Material.
Highly preferred embodiment of the present invention is described in further detail with reference to the accompanying drawing.
By taking certain Ti Alloy Strip reinforcing rib cylindrical part as an example, part material is 5083 aluminium alloys, and cylinder overall diameter is
250mm, length 1200mm, wall thickness 3mm, it is desirable that bending angle Ф be 35 degree, and press-bending after piece surface do not generate cracking,
It snaps, wall surface does not generate scuffing and impression inside and outside part, and maximum crimp height is no more than 10mm after press-bending.
Specific real-time mode is carried out by following processing step:
(1) prepare calculating process, rosin and for building can be used in filler volume required for calculating according to part size
Sand mixing is used as filler, and the outer diameter of the mass ratio and aluminium alloy pipe of rosin and building sand is related with the ratio of wall thickness, because
It is 250:3 for the outer diameter of aluminium alloy pipe and the ratio of wall thickness, so the mass ratio 200* (wall thickness/outer diameter) of rosin and building sand
=2.4:1；
The volume V=π (250mm) of filler required for calculating2X1200mm；
(2) cavity plate is prepared, as shown in Figure 2；
The cavity plate is rotate with a special-shaped figure；
The special-shaped figure is zhou duicheng tuxing, surrounds a closed figure by three straight lines and an abnormal-shaped curve,
Three straight lines are respectively straight line a, straight line b and straight line c, and the two straight line a and straight line b connecting with abnormal-shaped curve are parallel to each other, directly
Line c is vertical with two straight line a parallel to each other and straight line b；Wherein, the abnormal-shaped curve is by three sections of circular arc continuous transition shapes
At the radius of curvature of the circular arc of two sides is mutually all r1=300mm, and the radius of curvature of intermediate circular arc is r2=500mm；
The cavity plate is rotate using straight line d as axis, straight line d be the straight line parallel with straight line c and straight line d with
Central point, that is, minimum point distance of abnormal-shaped curve is r=570mm；
Cavity plate working face is variable curvature multi-section circular arc rounding off perpendicular to the section of bending deformed planar, on section at
The position radius of curvature r2 that shape part contacts earliest is bigger than two sides circular arc r1, is calculated according to cylinder overall diameter 250mm, interior lateral curvature
Rate radius r2 is 500mm, and two sides circular arc r1 is 300mm；Cavity plate working face is circular arc in the section of bending deformed planar, circular arc
Radius r should be smaller by 5% than the Inner arc R radius that Theoretical Design is bent tubing, and design Inner arc R is 600mm, by the way that r is calculated
It should be 570mm；
(3) it is blocked using the one end of end socket to tubing；
(4) tubing preprocessing process, heats the solution state of filler to 130 DEG C, and the wide-mouth for being 1.5L with volume is heat-insulated
Container slowly pours by several times and seals one end thin-wall aluminum alloy tubing to be bent, to its natural cooling in air；
(5) mold process is pre-installed, pipe outer surface, press bending apparatus workspace and pressure head are cleared up after filler is cooling, by tubing
It is placed on cavity plate, as shown in Figure 1, tubing axis-formed plane of soldering and sealing welding bead and press bending apparatus actuation direction acute angle
It is 90 degree；
(6) press bending process, bending angle Ф are 35 degree, bend 5 passages and carry out, and bend angle and adjust process, design inner circle
Arc R is 600mm, and bending angle Ф is 35 degree, and calculating deformation section inner circle arc length is 366.5mm, and design is bent 5 times, and every section is pressed
About 73mm points of 5 segment marks go out cavity plate and tubing contact point, as shown in Figure 3；Contact point should be adjusted after pressurization every time；Ram position tune
It is had suffered journey, distance of the pressure head middle line apart from cavity plate and tubing contact point should be in 300mm；It is put on the pressure head and cavity plate of press bending apparatus
The soft rubber pad of anti-scratch is set, soft rubber mat thickness should be in 15mm；
(7) last handling process after bend pipe, removes rosin and end socket, clears up piece surface, and zero after being bent
Part.
Obtained part after bending is carried out visually, no visual crackle generates；Fluorescent penetrant is carried out to part after bending
Test, inspection result are generated without part surface crack, and welding bead is without cracking；Template comparison is carried out to part after bending, fold is maximum
No more than 10mm.
Claims (8)
1. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold, it is characterised in that the step of this method includes:
(1) it calculates the volume V of filler and prepares filler；
(2) cavity plate is prepared；
(3) one end of tubing is blocked；
(4) step (1) ready filler is heated；
(5) filler heated in step (4) is circulated into the tubing for carrying out one end sealing end in step (3), it is then natural
It is cooling；
(6) tubing that step (5) encapsulating has filler is placed on the cavity plate prepared in step (2)；
(7) tubing is bent, the tubing after being bent；
In the step (2), the cavity plate is rotate with a special-shaped figure, and special-shaped figure is axial symmetry figure
Shape；
Special-shaped figure surrounds a closed figure by three straight lines and an abnormal-shaped curve, and three straight lines are respectively straight line a, straight line
B and straight line c, the two straight line a and straight line b connecting with abnormal-shaped curve are parallel to each other, straight line c and two straight lines parallel to each other
A and straight line b are vertical；Wherein, the abnormal-shaped curve is formed by three sections of circular arc continuous transitions, the radius of curvature phase of the circular arc of two sides
It is all r1, the radius of curvature of intermediate circular arc is r2, and r2 is greater than r1.
2. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: in the step (1), the volume of filler is consistent with the volume inside tubing, the volume V=π (D/2) of filler2L；D
For the diameter of tubing, L is the length of tubing.
3. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: in the step (1), filler includes rosin and building sand, and the mass ratio of rosin and building sand is 2.4:1.
4. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: the cavity plate is rotate using straight line d as axis, and straight line d is the straight line parallel with straight line c and straight line d and abnormal shape
Central point, that is, minimum point distance of curve is r.
5. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: in the step (4), heating temperature is 125-135 DEG C.
6. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: in the step (6), the plane and press bending apparatus that require central axis-tubing welding bead of tubing to be formed when placing tubing
The acute angle in actuation direction is not less than 70 degree.
7. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 1, feature exist
In: in the step (7), bends time-division multi-pass and carry out, when bending angle Ф is at 15 degree or less, divide 2-3 passage uniform
It bends, when bending angle Ф is when 15-45 is spent, 4-7 passage should be divided, bending angle Ф at least needs to bend 9 at 45 degree or more
It is secondary.
8. a kind of method for controlling large diameter thin wall aluminium alloy pipe buckle fold according to claim 6, feature exist
In: in the step (7), according to the radius R of the Inner arc of tubing theory external form after bending before bending, calculates and bend deformation section
Inner circle arc length, then corresponding deformation position with line segment marks corresponding length on tubing, the line segment that then will have been marked
Number is bent according to design and draws multistage line segment, each line segment endpoint as cavity plate and tubing contact point, gradually adjust by when pressurization
The contact point of whole cavity plate and tubing makes tubing homogeneous deformation；In press bending process, contact point and the pressure head middle line of cavity plate and tubing
Distance is 300-400mm；The soft rubber pad of anti-scratch is placed on the pressure head and cavity plate of the press bending apparatus, soft rubber pad is thick
Degree is 10-15mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711031986.9A CN107737825B (en) | 2017-10-29 | 2017-10-29 | A method of control large diameter thin wall aluminium alloy pipe buckle fold |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711031986.9A CN107737825B (en) | 2017-10-29 | 2017-10-29 | A method of control large diameter thin wall aluminium alloy pipe buckle fold |
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| CN107737825A CN107737825A (en) | 2018-02-27 |
| CN107737825B true CN107737825B (en) | 2019-01-01 |
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| 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 |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS57152319A (en) * | 1981-03-17 | 1982-09-20 | Sumitomo Metal Ind Ltd | Manufacture of elbow |
| CN101700543A (en) * | 2009-11-17 | 2010-05-05 | 江苏华阳管业股份有限公司 | Molding method of non-standard bent pipe mold |
| CN103753118A (en) * | 2013-12-09 | 2014-04-30 | 北京航星机器制造有限公司 | Bending method of large-diameter thin-wall aluminum pipe and die |
| CN104475517B (en) * | 2014-10-24 | 2016-08-24 | 上海通用金属结构工程有限公司 | A kind of heavy wall stainless steel tube bending method |
| CN105436270A (en) * | 2015-12-11 | 2016-03-30 | 北京有色金属研究总院 | Method for machining metal pipe with tapered elbow |
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