CN102873119B - Drawing die for rectangular flat steel tube - Google Patents
Drawing die for rectangular flat steel tube Download PDFInfo
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- CN102873119B CN102873119B CN201210404731.3A CN201210404731A CN102873119B CN 102873119 B CN102873119 B CN 102873119B CN 201210404731 A CN201210404731 A CN 201210404731A CN 102873119 B CN102873119 B CN 102873119B
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Abstract
The invention discloses a drawing die for a rectangular flat steel tube, which does not need to be corrected after heat treatment and can ensure the precision and surface flatness of the rectangular flat steel tube. The drawing die comprises a die body, wherein a drawhole of the drawing die comprises an inlet section, a transition section and a sizing section, and the sizing section comprises a pair of straight short surfaces, a pair of arc long surfaces and four corner arc surfaces which connect the straight short surfaces with the arc long surfaces; the transition section comprises four transition inclined planes which are joined with the straight short surfaces and the arc long surfaces and four transition corner curved surfaces which connect the two adjacent transition inclined planes; and the inlet section comprises four leading-in curved surfaces which are respectively joined with the corresponding transition inclined planes and protrude outwards and inlet corner curved surfaces which connect the two adjacent leading-in curved surfaces, the four leading-in curved surfaces are all quadric surfaces, and the opposite leading-in curved surfaces are symmetrically distributed. The drawing die is used for drawing a circular steel tube to form the rectangular steel tube.
Description
Technical field
The present invention relates to the stretching die in Metal Forming technical field, refer more particularly to the stretching die that round steel pipe is drawn into rectangle Flat steel pipe.
Background technology
Important fixture component when drawing die is cold drawing steel tube production, has been widely used in steel pipe reducing or/and in the production process of distortion.Utilize stretching die to carry out cold drawn forming to steel pipe, there is the features such as stock utilization is high, energy consumption is low, properties of product are good, production efficiency is high, with low cost.In drawing die, by the different tubing shape of its drawing moulding, be divided into again conventional drawing die and heterotypic stretching mould, for cold-drawn special-shaped tubing is heterotypic stretching mould (also claiming special-shaped stretching die); Have linerless core to divide by it, be divided into again empty sinking stretching die and lining core drawing die, the larger set of specifications of draw apart from time, because Drawing Force is huge, can only adopt empty sinking stretching die.
At present, no matter the stretching die of flat steel pipe (one in special-shaped stretching die), be empty sinking stretching die or lining core drawing die, all has following defect:
1, because the cross section of flat steel pipe and the entrance circular arc pattern of mould are tending towards complicated, the material of flat steel pipe drawing die is very restricted.Under normal circumstances, what specification was larger selects conventional 45# mould steel, less high-carbon alloy steel Cr12 material or the carbide alloy W-Co kind YG series selected.Because drawing die is after Overheating Treatment, sizing section and entrance circular arc produce deformation, although the sizing section of mould and the deformation of entrance circular arc are limited, but in the time of steel pipe drawing, when metal produces horizontal sliding, be subject to mould influence of crust deformation, the coefficient of the distortion of steel pipe is far longer than the deformation coefficient of mould, and be no longer the relation of 1: 1, thereby cause the stretched mould cold-drawn of steel pipe back plane degree depression serious; And, be subject to flat drawing die type structure impact (long outlying much larger than minor face), steel pipe pipe is in the time producing deformation through flat drawing die, there is the larger phenomenon of drop in the pressure of surrounding and frictional force, long limit pressure is far longer than minor face pressure, therefore by the flat steel pipe after drawing die, always there is the serious phenomenon of depression degree on long limit.Precision and surface smoothness through the flat steel pipe of drawing moulding all cannot reach designing requirement.
2,45# steel drawing die is after Overheating Treatment carburizing, and sizing section and entrance circular arc produce deformation, conventionally all adopts the way of revising drawing die to obtain former design size.When correction, because this material drawing die carburized (case) depth is generally between 0.8～1.0mm, at this, below the degree of depth, the matrix hardness of steel, intensity and wearability are poor, thereby cause revised die surface hardness to decline, cannot meet the case hardness designing requirement of drawing die.While adopting revised mould drawing flat steel pipe, between steel pipe and mould, frictional force can increase, and the surface of steel pipe can be damaged in the surface of mould, makes flat steel tube surface after moulding occur pulling and draws the defects such as silk.And, due to the lower hardness on drawing die surface, greatly shortened the service life of mould.
3, high-carbon alloy steel Cr12 material drawing die is after Overheating Treatment, and sizing section and entrance circular arc produce deformation, conventionally all adopts the way of revising drawing die to obtain former design size.When correction, because this material belongs to micro-distortion, high carbon alloy mould steel, the inside and outside hardness of mold materials, intensity, wearability are basically identical, so can not adopt machining mode correction, can only rely on manual type correction, make to revise that working strength is high, difficulty is larger, and inefficiency.
In addition, in the production process of utilizing drawing die drawing flat steel pipe, also find, while adopting empty sinking drawing die to carry out draw to steel pipe, support owing to not serving as a contrast core (internal mold) in empty sinking drawing die, the depression degree of flat steel pipe is more serious.
Summary of the invention
Technical problem to be solved by this invention is: the stretching die that does not need to revise and can guarantee the precision of rectangle Flat steel pipe and the rectangle Flat steel pipe of surface smoothness after a kind of heat treatment is provided.
For solving the problems of the technologies described above, the technical solution adopted in the present invention is: the stretching die of rectangle Flat steel pipe, comprising: die ontology, on die ontology, offer draw hole, and this draw hole comprises connected successively entrance, changeover portion, sizing section;
Sizing section comprises: respectively with the minor face of rectangle Flat steel pipe cross-sectional profiles, long limit with connect the corner circular arc on short, long limit corresponding a pair of straight short, the long face of a pair of arc and the corner arc surface of four connections straight short and the long face of arc, the summit of the described long face of arc is 3～5 ‰ of rectangle Flat steel pipe thickness to the air line distance of a pair of end line place plane of the long face of this arc;
Described changeover portion comprises: four transition inclined-planes that are connected mutually with straight short and the long face of arc and four are connected the changeover portion corner curved surface on adjacent transition inclined-plane between two, angle between transition inclined-plane and the respective face of sizing section is 3～4 °, the long face depression that it is ellipsoid that the midpoint of the linking boundary line on the long face of arc of sizing section and the transition inclined-plane being attached thereto is provided with surface, the major semiaxis of long face depression upper edge hole be rectangle Flat steel pipe cross-sectional profiles long limit 2/3 to 3/4, the length of long face depression upper edge hole, the ratio of semi-minor axis is 3: 1～1.5, the degree of depth of long face depression is 0.8～1% of rectangle Flat steel pipe wall thickness,
Described entrance comprises: four cambered outwards importing curved surfaces that are connected mutually with corresponding transition inclined-plane respectively and be connected the entrance corner curved surface of adjacent importing curved surface between two, four import curved surface and are quadratic surface, relative importing curved surface is arranged symmetrically with, import the axial subsequent corrosion of curved surface and equal this to importing distance between the outer bead of curved surface summit and deduct and this being to importing the ultimate range between relative two faces of the corresponding sizing section of curved surface, divided by being four times in this importing curved surface, outer opening's edge the square value of the angle sine between line and the axis of two axial end points, importing the circumferential subsequent corrosion of curved surface equals to hang down and is cut in 0.9～1.15 times of distance between two summits of above-mentioned axial curved surface.
Described die ontology is also provided with in the outside of sizing section the nib communicating with sizing section, form the outlet section of draw hole, this outlet section comprises: four are connected the outlet corner curved surface on adjacent outlet inclined-plane between two with straight short the outlet inclined-plane being connected mutually with the long face of arc and four.
4～5%, 24～26%, 8～10% and 60～64% of the thickness of the die ontology described in described outlet section, sizing section, changeover portion and entrance accounts for separately.
Angle between described outlet inclined-plane and the respective face of sizing section is 30～45 °.
Straight short of described sizing section is provided with the midpoint of the linking boundary line on the transition inclined-plane being attached thereto short the depression that surface is ellipsoid, short depression upper edge hole major semiaxis be rectangle Flat steel pipe cross-sectional profiles minor face 2/3 to 3/4, the ratio of the long and short semiaxis of short depression upper edge hole is 3: 1～1.5, and the degree of depth of short depression is 0.8～1% of rectangle Flat steel pipe wall thickness.
Between described sizing section and changeover portion, be provided with smooth transition surface.
The radius of described smooth transition surface is 0.8～0.9 of sizing section length.
The invention has the beneficial effects as follows: the long face that the surface that is arranged on the midpoint of the long face of arc of sizing section and the linking boundary line on the transition inclined-plane that is attached thereto is ellipsoid caves in, can offset sizing section and entrance circular arc in heat treatment process and produce outside deformation, thereby the stretching die obtaining need not be revised, both reduced cost of manufacture, guarantee again the hardness of die surface, pressure and the frictional force of limit face while effectively having reduced steel pipe deformation, ensure steel pipe deformation smooth transition.The structure of described sizing section, changeover portion and entrance, can meet the requirement of described rectangle Flat steel pipe shape and size, and, also prevent that the long limit of flat steel pipe from producing depression, obtain high precision plane Flat steel pipe; In addition, due to the arranged outside at sizing section outlet section, to the outer interruption-forming protection of sizing section, extended the service life of described stretching die, and made the stability of Flat steel pipe precision obtain effective guarantee; In addition, be arranged on the moderate smooth transition surface of radian between sizing section and changeover portion, can further reduce wear, extend the service life of described stretching die, improve the quality of rectangle Flat steel pipe.
Accompanying drawing explanation
Fig. 1 is the structural representation of cold-drawn mould of the present invention.
Fig. 2 is the longitudinal cutting structure schematic diagram of Fig. 1.
Fig. 3 is the schematic diagram that the cross cut structure transposition 90 of Fig. 1 is spent
Fig. 4 is the figure of structure for amplifying signal of K part in Fig. 1.
Fig. 5 is the figure of structure for amplifying signal of J part in Fig. 2.
Fig. 6 is the cross sectional representation that adopts the rectangle Flat steel pipe that pulls into of stretching die of the present invention.
In Fig. 1 to Fig. 6: 1, die ontology, 11, first import curved surface, and 12, second import curved surface, 13, line, 21, First Transition inclined-plane, 22, the second transition inclined-plane, 31, straight short, 32, the long face of arc, 41, first export inclined-plane, and 42, second export inclined-plane; I, entrance, II, changeover portion, III, sizing section, IV, outlet section.
The specific embodiment
Below in conjunction with accompanying drawing, describe specific embodiments of the present invention in detail.
As shown in Figure 1, Figure 2 and Figure 3, the stretching die of rectangle Flat steel pipe of the present invention, comprise: die ontology 1, on die ontology 1, offer and comprise: the draw hole of connected entrance I, changeover portion II and sizing section III and outlet section IV successively, outlet section IV, sizing section III, changeover portion II and entrance I account for separately die ontology 1 thickness 4.5%, 25%, 9% and 61.5%, sizing section III comprises: respectively with minor face, the long limit of the cross-sectional profiles of the rectangle Flat steel pipe 8 shown in Fig. 6 with connect the corner circular arc on short, long limit corresponding a pair of straight short 31, the long face 32 of a pair of arc and the corner arc surface of four connections straight short 31 and the long face 32 of arc, the summit of the long face 32 of arc is 3～5 ‰ of rectangle Flat steel pipe thickness to the air line distance H2 of a pair of end line place plane of the long face of this arc---shown in Figure 4, described changeover portion II comprises two changeover portion corner curved surfaces that are connected respectively First Transition inclined-plane 21 and the second transition inclined-plane 22 with straight short the 31 First Transition inclined-plane 21 being connected mutually, two the second transition inclined-planes 22 that are connected mutually with the long face 32 of arc respectively and four, angle α between First Transition inclined-plane 21 and the second transition inclined-plane 22 and the respective face of sizing section III is 3～4 °---shown in Figure 5, between sizing section III and changeover portion II, be provided with smooth transition surface 23, the radius of smooth transition surface 23 is 0.8～0.9 of sizing section III length, as shown in Figure 3, the long face 32 of two arcs of sizing section III is respectively arranged with the midpoint of the linking boundary line on the second transition inclined-plane 22 that correspondence is connected with it the long face depression M that surface is ellipsoid, the major semiaxis of the upper edge hole of long face depression M be the cross-sectional profiles of rectangle Flat steel pipe 8 long limit 2/3 to 3/4, the ratio of the long and short semiaxis of the upper edge hole of long face depression M is 3:1～1.5, and the degree of depth of long face depression M is 0.8～1% of rectangle Flat steel pipe 8 wall thickness, described entrance I comprises: two cambered outwards the first importing curved surfaces 11 that are connected mutually with corresponding First Transition inclined-plane 21 respectively, two cambered outwards second importing curved surface 12 and four and are connected the first entrance corner curved surface that imports curved surface 11 and the second importing curved surface 12 of being connected mutually with corresponding the second transition inclined-plane 22 respectively, two first import curved surface 11 and second import curved surface 12 be quadratic surface, and, two first import curved surface 11 and are arranged symmetrically with, two second import curved surface 12 and are arranged symmetrically with, the axial subsequent corrosion that the first importing curved surface 11 and second imports curved surface 12 is identical with the computational methods of circumferential subsequent corrosion, take the first importing curved surface 11 as example, as shown in Figure 3, first imports the axial subsequent corrosion R1 of curved surface 11 equals this and distance H 4 between outer bead summit of the first importing curved surface 11 is deducted and this is to the ultimate range H3 between relative two faces of the corresponding sizing section III of the first importing curved surface 11, divided by be four times in the first importing curved surface 11 in, outer opening's edge the square value of the angle β sine between line 13 and the axis of two axial end points, that is: R1=(H4-H3) ÷ (4 × Sin
2β), its circumferential subsequent corrosion equals to hang down and is cut in 0.9～1.15 times of distance H 1 between two summits of above-mentioned axial curved surface.In the present embodiment, a pair of straight short 31 of described sizing section III is respectively arranged with the midpoint of the linking boundary line on the First Transition inclined-plane 21 being attached thereto short the depression L that surface is ellipsoid, the major semiaxis of short depression L upper edge hole be rectangle Flat steel pipe 8 cross-sectional profiles minor face 2/3 to 3/4, the ratio of the long and short semiaxis of short depression L upper edge hole is 3: 1～1.5,0.8～1% of the degree of depth rectangle Flat steel pipe wall thickness of short depression L; Described outlet section IV comprises: two are connected the first outlet inclined-plane 41 and second and export respectively the outlet corner curved surface on inclined-plane 42 with a pair of straight short 31 the first outlet inclined-plane 41 being connected mutually, the second outlet inclined-plane 42 that two are connected mutually with the long face 32 of a pair of arc respectively and four, and described first exports inclined-plane 41 and the second angle exporting between inclined-plane 42 and the respective face of sizing section III is 30～45 °.
Claims (7)
1. the stretching die of rectangle Flat steel pipe, comprising: die ontology, is characterized in that: on described die ontology, offer draw hole, this draw hole comprises connected successively entrance, changeover portion, sizing section;
Sizing section comprises: respectively with the minor face of rectangle Flat steel pipe cross-sectional profiles, long limit with connect the corner circular arc on short, long limit corresponding a pair of straight short, the long face of a pair of arc and the corner arc surface of four connections straight short and the long face of arc, the summit of the described long face of arc is 3～5 ‰ of rectangle Flat steel pipe thickness to the air line distance of a pair of end line place plane of the long face of this arc;
Described changeover portion comprises: four transition inclined-planes that are connected mutually with straight short and the long face of arc and four are connected the changeover portion corner curved surface on adjacent transition inclined-plane between two, angle between transition inclined-plane and the respective face of sizing section is 3～4 °, the long face depression that it is ellipsoid that the midpoint of the linking boundary line on the long face of arc of sizing section and the transition inclined-plane being attached thereto is provided with surface, the major semiaxis of long face depression upper edge hole be rectangle Flat steel pipe cross-sectional profiles long limit 2/3 to 3/4, the length of long face depression upper edge hole, the ratio of semi-minor axis is 3:1～1.5, the degree of depth of long face depression is 0.8～1% of rectangle Flat steel pipe wall thickness,
Described entrance comprises: four cambered outwards importing curved surfaces that are connected mutually with corresponding transition inclined-plane respectively and be connected the entrance corner curved surface of adjacent importing curved surface between two, four import curved surface and are quadratic surface, relative importing curved surface is arranged symmetrically with, import the axial subsequent corrosion of curved surface and equal this to importing distance between the outer bead of curved surface summit and deduct and this being to importing the ultimate range between relative two faces of the corresponding sizing section of curved surface, divided by four, again divided by this importing curved surface, outer opening's edge the square value of the angle sine between line and the axis of two axial end points, importing the circumferential subsequent corrosion of curved surface equals to hang down and is cut in 0.9～1.15 times of distance between two summits of above-mentioned axial curved surface.
2. the stretching die of rectangle Flat steel pipe as claimed in claim 1, it is characterized in that: described die ontology is also provided with in the outside of sizing section the nib communicating with sizing section, form the outlet section of draw hole, this outlet section comprises: four are connected the outlet corner curved surface on adjacent outlet inclined-plane between two with straight short the outlet inclined-plane being connected mutually with the long face of arc and four.
3. the stretching die of rectangle Flat steel pipe as claimed in claim 2, is characterized in that: 4～5%, 24～26%, 8～10% and 60～64% of the thickness of the die ontology described in described outlet section, sizing section, changeover portion and entrance accounts for separately.
4. the stretching die of rectangle Flat steel pipe as claimed in claim 2, is characterized in that: the angle between described outlet inclined-plane and the respective face of sizing section is 30～45 °.
5. the stretching die of rectangle Flat steel pipe as claimed in claim 1, it is characterized in that: straight short of described sizing section is provided with the midpoint of the linking boundary line on the transition inclined-plane being attached thereto short the depression that surface is ellipsoid, short depression upper edge hole major semiaxis be rectangle Flat steel pipe cross-sectional profiles minor face 2/3 to 3/4, the ratio of the long and short semiaxis of short depression upper edge hole is 3:1～1.5, and the degree of depth of short depression is 0.8～1% of rectangle Flat steel pipe wall thickness.
6. the stretching die of the rectangle Flat steel pipe as described in any one in claim 1 to 5, is characterized in that: between described sizing section and changeover portion, be provided with smooth transition surface.
7. the stretching die of rectangle Flat steel pipe as claimed in claim 6, is characterized in that: the radius of described smooth transition surface is 0.8～0.9 of sizing section length.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210404731.3A CN102873119B (en) | 2012-10-22 | 2012-10-22 | Drawing die for rectangular flat steel tube |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210404731.3A CN102873119B (en) | 2012-10-22 | 2012-10-22 | Drawing die for rectangular flat steel tube |
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| Publication Number | Publication Date |
|---|---|
| CN102873119A CN102873119A (en) | 2013-01-16 |
| CN102873119B true CN102873119B (en) | 2014-05-14 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201210404731.3A Active CN102873119B (en) | 2012-10-22 | 2012-10-22 | Drawing die for rectangular flat steel tube |
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Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103143629B (en) * | 2013-03-06 | 2016-08-31 | 青岛鑫家达工贸有限公司 | Steel pipe flattens mould and steel pipe flattens equipment and steel pipe flattening method |
| CN104741400B (en) * | 2015-04-13 | 2016-08-17 | 江苏华程工业制管股份有限公司 | A kind of rectangle steel tubes inequilateral empty sinking mould |
| CN108906902B (en) * | 2018-08-22 | 2024-09-13 | 广东海亮铜业有限公司 | Die and D-shaped pipe machining device |
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|---|---|---|---|---|
| JPS6015015A (en) * | 1983-07-05 | 1985-01-25 | Hitachi Cable Ltd | Processing equipment of metallic tube with grooved inner surface |
| AU5597086A (en) * | 1985-04-17 | 1986-11-06 | Shahum, Christian | Die device for forming tube from a metal band |
| CN2749595Y (en) * | 2004-12-13 | 2006-01-04 | 宁福宏 | Square tube core |
| CN101856790A (en) * | 2009-04-10 | 2010-10-13 | 许畴猛 | Production process for forming, forging and pressing square tubes in one step |
| CN201950112U (en) * | 2010-12-01 | 2011-08-31 | 上海飞轮有色新材料股份有限公司 | Drawing die of rectangular eccentric copper tubular lead for induction coil in inductive steel-making furnace |
| CN202845478U (en) * | 2012-10-22 | 2013-04-03 | 江苏华程工业制管股份有限公司 | Drawing mold of rectangular flat steel tube |
-
2012
- 2012-10-22 CN CN201210404731.3A patent/CN102873119B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6015015A (en) * | 1983-07-05 | 1985-01-25 | Hitachi Cable Ltd | Processing equipment of metallic tube with grooved inner surface |
| AU5597086A (en) * | 1985-04-17 | 1986-11-06 | Shahum, Christian | Die device for forming tube from a metal band |
| CN2749595Y (en) * | 2004-12-13 | 2006-01-04 | 宁福宏 | Square tube core |
| CN101856790A (en) * | 2009-04-10 | 2010-10-13 | 许畴猛 | Production process for forming, forging and pressing square tubes in one step |
| CN201950112U (en) * | 2010-12-01 | 2011-08-31 | 上海飞轮有色新材料股份有限公司 | Drawing die of rectangular eccentric copper tubular lead for induction coil in inductive steel-making furnace |
| CN202845478U (en) * | 2012-10-22 | 2013-04-03 | 江苏华程工业制管股份有限公司 | Drawing mold of rectangular flat steel tube |
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| CN102873119A (en) | 2013-01-16 |
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