CN1201878C - Cold machining process for manufacturing thin-wall copper pipe and thin-wall copper pipe manufactured by cold machining process - Google Patents
Cold machining process for manufacturing thin-wall copper pipe and thin-wall copper pipe manufactured by cold machining process Download PDFInfo
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- CN1201878C CN1201878C CN 03109033 CN03109033A CN1201878C CN 1201878 C CN1201878 C CN 1201878C CN 03109033 CN03109033 CN 03109033 CN 03109033 A CN03109033 A CN 03109033A CN 1201878 C CN1201878 C CN 1201878C
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- copper pipe
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Abstract
A cold-working technology for making thin-wall copper pipe and the thin-wall copper pipe made by it is a continuous casting state T2Or TP2The copper pipe blank is manufactured by a cold working process combining cold rolling and cold drawing with large deformation. Its finished product tube is phi 60±0.04X 2mm, and the total deformation is allowed to reach 92-95%; finished pipe phi 32±0.03X 0.5mm, total deformation amount allowed to reach 98.2-98.6%, roughness R of inner and outer surfaces of copper pipeaLess than or equal to 0.4 mu m, and the ratio of the wall thickness to the diameter t/D is less than or equal to 0.0156. Tensile strength sigma of finished copper pipeb＝350～420MPaElongation delta10Not less than 10%. The manufacturing process of the invention can be simplified to cooling-offThe subsequent continuous casting pipe blank is directly subjected to cold rolling, cold drawing and cold rolling or the cold rolling is finished by two working procedures. Compared with the conventional manufacturing process, the method reduces six working procedures, and is a new technical product with less process passes, less investment, small occupied area, less energy consumption, low cost, high yield, good surface quality and high dimensional precision.
Description
Technical field
The present invention relates to a kind of pipe, the specifically a kind of cold machining process of thin-wall copper pipe and thin-wall copper pipe of manufacturing thereof made.
Background technology
Metal rigidity pipe of the prior art, common have iron pipe, steel pipe, stainless steel tube, a copper pipe.For drinking-water pipe, used in the past galvanized pipe, because of its in the mill, all needing through overheated, cold working is to adopt hot-dip at last, just there is serious pollution its technology in itself, so do not get consumer reception.Iron pipe is easy to get rusty, stainless steel tube non-corrosive, pollution-free, attractive and durable, but the nickel of its contained usefulness, chromium element, cost an arm and a leg, cause cost higher, and the manufacturing process complexity, need through melting-pour into a mould-strip off the skin-crop-boring-heating-hot extrusion, carry out again that multi-pass is cold rolling, cold-drawn, annealing and cold-drawn form.Present T
2/ TP
2The traditional conventional manufacturing process of copper pipe, be with stainless steel-like with, but price will be lower than stainless steel tube, causes both at home and abroad demand to copper pipe rising year by year, has the trend that replaces.And the technology that follows the usual practice is brought is that equipment investment is big, and the processing passage is many, and lumber recovery is low, the deficiencies of extruding through hot extrusion such as the easy off-centre of tubing, and all be unable to do without hot-working, and also increased the consume of heat energy, force it must reform technology.
Summary of the invention
The present invention's purpose is deficiency, the reduction processing technology program for fear of above-mentioned traditional common process, improves T simultaneously
2/ TP
2The quality of continuous casting attitude shaping pipe, and the thin-wall copper pipe that provides a kind of cold machining process to make.
Task of the present invention is to realize like this; A kind of cold machining process of thin-wall copper pipe and thin-wall copper pipe of manufacturing thereof made, wherein the technology manufacturing is to adopt cold rolling, cold-drawn, it is characterized in that making cold rolling, the cold-drawn processing technology of thin-wall copper pipe, is to select continuous casting attitude T for use
2/ TP
2The copper pipe base, for columanar structure's structure (metallographic structure is seen shown in the accompanying drawing 1), at room temperature, technical process all adopts cold machine-shaping, its processing step is cold rolling-cold-drawn-cold rolling, that is: a, at first be on cold-rolling mill, the pass deformation of employing is 80%～83%, mill speed is 80 times/min, columanar structure's structure is processed with large deformation, become the deformation states institutional framework, this is a roughing technology; B, with the T after the roughing
2/ TP
2Copper pipe is implemented cold-drawn and is shaped: on drawbench tube reducing and attenuate wall thickness are implemented in the copper pipe cold-drawn, its draw speed is 10M/min, and pass deformation is 15%～20%; C, once more carry out cold rolling: adopting pass deformation on cold-rolling mill is 52%～55%, and mill speed is 90 times/min, the inside and outside surface roughness R of copper pipe
a≤ 0.4 μ m; The ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0333, and total deformation reaches 92%～95%.Processing step recited above can be with twice cold rolling process feature wherein, and each is made two work steps respectively and replaces i.e.: the cold rolling II-cold-drawn of the cold rolling I--cold rolling IV of cold rolling III-.Adopting cold rolling speed is 70～90 times/min, and the pass deformation of cold rolling I is 67%～70%, and the pass deformation of cold rolling II is 34%～37%, inside and outside surface roughness R
a≤ 0.6 μ m; Cold-drawn speed is 10M/min, and the cold-drawn pass deformation is 33%～36%; The pass deformation 73%～76% of cold rolling III, cold rolling speed are 90 times/min, and the ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0268, the inside and outside surface roughness R of copper pipe
a≤ 0.4 μ m; Cold rolling IV repeats it with reference to cold rolling III, and the ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0156, and total deformation allows to reach 98.2%～98.6%.
Adopt above-mentioned cold machining process; the thin-wall copper pipe metallographic structure is by as cast condition columanar structure structure, is transformed into the deformation states institutional framework, when in manufacturing procedure; be not hot-working character, when the annealing homogeneous micronization is handled, obtaining recrystallized structure structure mean grain size is 46 μ m.
The continuous casting attitude T that is adopted in the above-mentioned technology manufacturing
2/ TP
2Be to be material pipe vertical or that horizontal is cast.
Adopt the above-mentioned thin-wall copper pipe of being made by cold machining process, the metallographic structure that it is characterized in that the finished product copper pipe is that deformation states institutional framework, the external diameter of column crystal is φ 60
± 0.04～φ 32
± 0.03Mm, wall thickness are 2～0.5mm, and the external diameter tolerance is ± 0.04～0.03mm, the inside and outside lip-deep roughness R of copper pipe
aThe ratio of≤0.4 μ m thickness of pipe wall t and outer diameter D is t/D≤0.0333～0.0156, the tensile strength sigma of copper pipe
b=350～420MP
aThe thin-wall copper pipe that the present invention makes can be used as water pipe, tracheae or other liquid lines.
The advantage that the present invention and prior art are compared is; Whole processing all is cold technology, compares with the conventional processing technology of tradition, has reduced by five to six times processing passage, so cost decreases.Because of its no hot-working program, correspondingly reduced consumption, the heat discharging of firing equipment and heat energy, avoid thermal defect and off-centre simultaneously, make the lumber recovery height, surface quality is good, and obtains the high product of dimensional accuracy, high accuracy thin-wall copper pipe of the present invention is particularly suitable for doing drinking-water pipe.
The present invention is with continuous casting attitude T
2Or TP
2The high accuracy thin-wall copper pipe that pipe is made, the cold machining process that is carried out, its concrete operation is composed as follows:
1) single chassis two-high pilger cold-rolling mill cold rolling T
2Or TP
2Copper pipe
The as cast condition T that continuous casting is obtained at first
2Or TP
2The copper pipe base, at room temperature, be cut into fixed length and carry out roughing: place periodic two-high pilger cold-rolling mill table top, and penetrate core bar and coupled plug enters roller-way, push in the middle of the die cavity of the upper and lower band semi-circular grooves of two ring-like rollers, in long deformed area, implement the back and forth rolling of aximal deformation value, 80 times/min of mill speed.Deflection is 80%～83%, obtains the deformation states institutional framework, and metallographic structure is seen shown in the accompanying drawing 2.
2) T after roughing
2Or TP
2Copper pipe is implemented cold-drawn and is made shape
As cast condition copper pipe base through after the cold deformation 80%～83%, is pressed into 150～180mm length on heading machine, to square clamping pressure head, its square clamping pressure head catercorner length must be less than former calibrating strap size from circular gradual transition.Insert core bar and coupled short plug from copper pipe other end endoporus, deliver in the lump on the drawbench frame of 8-10 ton.Again the pressure head end was pushed away former, driving the drawbench dolly advances, make the jaw on the dolly bite the copper pipe pressure head end that stretches out from former, restart drawbench master motor, driving the drawbench dolly retreats, at the aft mounted pneumatic or hydraulic stop pin-lift arrangement of drawbench, advance core bar simultaneously to former calibrating strap position.Drawbench dolly traction copper pipe base by tube reducing, is subjected to the plug constraint to decide internal diameter and subtract wall thickness simultaneously to be pulled out draw speed 10M/min by former.
3) multiple roll cold pilger mill cold rolling T
2Or TP
2Copper pipe
With the copper pipe after the cold-drawn, through crop and after cutting sizing, penetrate core bar and coupled plug, from the feeding stand, will pull out the back copper pipe, push in the multiple roll cold pilger mill roll gap sizing die cavity by propulsive mechanism.The multiple roll cold pilger mill is through back and forth rolling, and 90 times/min of its mill speed rolls into the dimensions that sets value external diameter, internal diameter or wall thickness.
Description of drawings
Change the accompanying drawing description for executing metallographic real of the present invention below.
Fig. 1, be continuous casting attitude T
2/ TP
2Copper pipe base columanar structure structure.
Fig. 2, be to become deformation states institutional framework (φ 35 * 1 X200) after the large deformation processing of Fig. 1.
The specific embodiment
Embodiment 1: make the less pipe in aperture and also cold rolling process can be divided work two passages finish.
1) with φ 103.0mm, the T of wall thickness 18.0mm
2The continuous casting copper pipes base obtains φ 101.6mm behind the milling outer surface, wall thickness 17.3mm, and section fixed length is several as blank.Penetrate core bar and coupled plug on the cold pipe machine of LG-90 periodic two rollers, start the propulsive mechanism that propulsion electric machine is connected, make T
2Copper blank pipe moves on core bar and coupled plug, pushes and matches in the upper and lower semicircle die cavity of the ring-like roller that installs.LG-90 cold pilger mill afterbody has the device that limits the core bar displacement, prevents that the core bar string is moving.Start main drive motor and make the crank pull bar connect the gear that is connected with roll, make the roll rotation and make oscillating rectilinear motion along tooth bar, mill speed is 80/min.Make copper blank pipe in the upper and lower semicircle die cavity of two rolls and be subjected to the constraint of copper blank pipe internal taper plug, and, operation of rolling distortion in the deformed area, gradual change produces deformation.Finally roll into 69 * 4.5mm into φ, pass deformation allows to reach 80%～83%.
2) again with the T of φ 69 * 4.5mm
2Copper pipe one end 150～180mm is long to insert heading machine, is pressed into from the shape of circle to the square transition of gradual change, T
2Copper pipe other end endoporus penetrates core bar and coupled short plug.Be provided with the ejection core bar at 8 tons of drawbench lathe afterbodys, make plug be limited to the device at former calibrating strap position.With propulsive mechanism with T
2Copper pipe pressure head end pushed away the former inner chamber that cold drawing tube machine has been matched.Stretch out the outer pressure head end of die cavity, utilize the traction of drawing dolly to make copper pipe by setting the negative impression that apolegamy installs, draw speed 10M/min finally obtains the copper pipe of φ 65 * mm, and pass deformation allows to reach 15.9%～20%.
3) the 3rd passage is inserted the copper pipe of φ 65 * 4mm in the LD-60 multiple roll cold pilger mill sizing die cavity by the method for same material loading, punching bar and plug of first passage, implements reciprocating type finish rolling, 90 times/min of mill speed.Finally roll into φ 60
± 0.04The accurate copper pipe of * 2mm certain-length.Its inside and outside surface roughness R
a≤ 0.4 μ m, t/D≤0.0333 (t-copper pipe wall thickness, D-external diameter of pipe), pass deformation allows to reach 52.5%～55%, and total deformation allows to reach 92%～95%.Dissect copper pipe and stretch, measure the strong σ of tension
b=350～420MP
a, percentage elongation δ
10〉=10%.
Embodiment 2: continuous casting attitude TP
2The copper pipe base, the thin-walled copper plumbing is processed in cold rolling and a time cold-drawn through four-pass.
1) with φ 72.5 * 15.7mm, certain-length continuous casting attitude TP
2The copper pipe base places LG-55 periodic two-high pilger cold-rolling mill rack table; Penetrate apolegamy suitable core bar and plug coupled, that have certain taper (the tapering size is decided according to technological parameter) at its copper pipe base endoporus, the more related plug of core bar pushed upper and lower two roller centre of surfaces earlier, along the circumferential direction have the appropriate location size gradual change, in the semi-circular grooves; Starting propulsion electric machine uses the pusher push rod with TP
2The copper pipe base pushes the arrival end of upper and lower two rolls.LG-55 cold pilger mill afterbody is provided with the core bar anticreeping device.Send cooling fluid to restart drive motors earlier, drive the gear that connects roll by crank connecting link, make roll rotation and reciprocating along tooth bar, mill speed is 70 times/min, and propulsive mechanism is realized sending to synchronously simultaneously.Comply with the size of the calibrating strap of two roll grooves at last, guarantee the external diameter of cold rolling back tubing; Internal diameter relies on plug to limit to reach dimensional accuracy, last cold rolling φ 52 * 6.4mm copper pipe that goes out.Its roughness relies on the precision of moulds of industrial equipment and the quality of lubricating oil to realize.Pass deformation allows to reach 67.4%～70%.
2) match core bar and coupled plug again, penetrated φ 52 * 6.4mm TP
2In the copper pipe endoporus, insert in the lump on the LD-60 multiple roll cold pilger mill table top.Plug is sent to earlier and has been matched in the head in the roll die cavity that installs and set dimensions, adjusts the optimum position, again with the afterbody of cold pilger mill, with the triangle chuck clamp core bar make its can not before and after displacement; Start pusher, φ 52 * 6.4mm copper pipe material is moved, shifts onto the arrival end of cold pilger mill head roll on core bar, after starting the cooling fluid motor, restart main drive motor, head is done reciprocating linear motion on slideway by the crank pull bar, mill speed is 90 times/min; Roll in head along shaping curved surface track slideway toward the compound compression copper pipe, the final cold rolling copper pipe that goes out φ 47 * 4.5mm.Its inside and outside surface roughness R
a≤ 0.6 μ m, pass deformation allows to reach 34.5%～37%.
3) again with the TP of φ 47 * 4.5mm
2It is long that copper pipe one end is pressed into 150～180mm with heading machine, from circle to square transition, crossfade into square cramping head, the other end directly penetrates good core bar of apolegamy and coupled short plug.The pressure head end of copper pipe and plug, insert 10 tons of drawbenches in the lump and matched in the negative impression that installs, stretch out the pressure head end of die cavity outside, clamp with the trailer wagon jaw, start main drive motor and make the trailer wagon backward going, simultaneously the pneumatic or hydraulic mandril of drawbench afterbody promotes core bar and advances, plug is advanced to former calibrating strap position, copper pipe is gone out by cold-drawn from negative impression smoothly, its draw speed is 10M/min, just obtain φ 41 * 3.4mm copper pipe, pass deformation allows to reach 33.2%～36%.
4) again from the TP of φ 41 * 3.4mm
2The copper pipe endoporus penetrates the core bar matched and coupled plug; From LD-60 cold pilger mill table top, with TP
2Copper pipe and core bar insert in the head in the lump, matched in the die cavity that the multiple roll that installs forms, and adjusts the suitable location of plug, and with the triangle chuck of tail the core bar clamping being made it can not displacement; Start the pusher motor, the ejection copper pipe moves to the arrival end of head die cavity on core bar; After starting the cooling fluid motor, restart main drive motor, make in the head roll rotation and do reciprocating, 90 times/min of mill speed, the last cold rolling φ 35 that goes out
± 0.04The copper pipe of * 1.0mm.Pass deformation allows to reach 73.4%～76%, and wall thickness and diameter be than t/D≤0.0286, its inside and outside surface roughness R
a≤ 0.4 μ m.
5) passage technical process repetition 4) is with φ 35
± 0.04* 1.0mm copper pipe is rolled into φ 32 on the LD-60 cold pilger mill
± 0.04* 0.5mm thin-walled copper plumbing, its surfaces externally and internally roughness R
a≤ 0.4 μ m, total deformation allows to reach 98.2%～98.6%, and wall thickness and diameter are than t/D≤0.0156.
Claims (5)
1, a kind of cold machining process of making thin-wall copper pipe, wherein the technology manufacturing is to adopt cold rolling, cold-drawn, it is characterized in that: make the cold machining process of thin-wall copper pipe, select continuous casting attitude T for use
2/ TP
2The copper pipe base, be columanar structure's structure, at room temperature, the whole employings of technical process are cold rolling, cold-drawn shapes, its processing step is cold rolling-cold-drawn-cold rolling, that is: a, at first be on cold-rolling mill, adopting pass deformation is 80%～83%, mill speed is 80 times/min, columanar structure's structure is processed with large deformation, become the deformation states institutional framework, this is a roughing technology; B, with the T after the roughing
2/ TP
2Copper pipe is implemented cold-drawn and is shaped: on drawbench tube reducing and attenuate wall thickness are implemented in the copper pipe cold-drawn, adopting cold-drawn system speed is 10M/min, and pass deformation is 16%～20%; C, once more carry out cold rolling: adopting pass deformation on cold-rolling mill is 52%～55%, and mill speed is 90 times/min, and the inside and outside surface roughness of copper pipe is R
a≤ 0.4 μ m; The ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0333, and total deformation reaches 92%～95%.
2, the cold machining process of manufacturing thin-wall copper pipe according to claim 1, it is characterized in that: described processing step, can be with twice cold rolling process feature wherein, make two work steps respectively replaces with each, that is: cold rolling I-cold rolling II-cold-drawn-cold rolling III-cold rolling IV, adopting cold rolling speed is 70～90 times/min, and the pass deformation of cold rolling I is 67%～70%, the pass deformation of cold rolling II is 34%～37%, inside and outside surface roughness R
a≤ 0.6 μ m; Cold-drawn speed is 10M/min, and the cold-drawn pass deformation is 33%～36%; The pass deformation 73%～76% of cold rolling III, cold rolling speed are 90 times/min, and the ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0268, the inside and outside surface roughness R of copper pipe
a≤ 0.4 μ m; Cold rolling IV repeats it with reference to cold rolling III, and the ratio of thickness of pipe wall t and outer diameter D is t/D≤0.0156, and total deformation allows to reach 98.2%～98.6%.
3, the cold machining process of manufacturing thin-wall copper pipe according to claim 1 and 2 is characterized in that: the continuous casting as cast condition T that is adopted in the technology manufacturing
2/ TP
2, be to be material pipe vertical or that horizontal is cast.
4, a kind of thin-wall copper pipe of being made by cold machining process according to claim 1 and 2, it is characterized in that: the metallographic structure of finished product copper pipe is the deformation states institutional framework of as cast condition column crystal, and external diameter is φ 60
± 0.04～φ 32
± 0.03Mm, wall thickness are 2～0.5mm, and the external diameter tolerance is ± 0.04～0.03mm, the roughness R on the inside and outside surface of copper pipe
a≤ 0.4 μ m; Ratio t/D≤0.0333～0.0156 of thickness of pipe wall t and outer diameter D, tensile strength sigma
6=350～420MP
aPercentage elongation δ
10〉=10%.
5, the thin-wall copper pipe of making according to claim 1 or 2 or 3 described cold machining process, it is characterized in that: the thin-wall copper pipe metallographic structure is by as cast condition columanar structure structure, be transformed into the deformation states institutional framework, when in manufacturing procedure, be not hot-working character, when the annealing homogeneous micronization is handled, obtain to such an extent that recrystallized structure structure mean grain size is 46 μ m.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03109033 CN1201878C (en) | 2003-04-03 | 2003-04-03 | Cold machining process for manufacturing thin-wall copper pipe and thin-wall copper pipe manufactured by cold machining process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 03109033 CN1201878C (en) | 2003-04-03 | 2003-04-03 | Cold machining process for manufacturing thin-wall copper pipe and thin-wall copper pipe manufactured by cold machining process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1439465A CN1439465A (en) | 2003-09-03 |
| CN1201878C true CN1201878C (en) | 2005-05-18 |
Family
ID=27796704
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 03109033 Expired - Fee Related CN1201878C (en) | 2003-04-03 | 2003-04-03 | Cold machining process for manufacturing thin-wall copper pipe and thin-wall copper pipe manufactured by cold machining process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1201878C (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100448597C (en) * | 2004-09-30 | 2009-01-07 | 中铝洛阳铜业有限公司 | Cupronickel condensation tube production process using disk stretch |
| CN100503898C (en) * | 2007-05-03 | 2009-06-24 | 福建省京泰管业有限公司 | Method for manufacturing steel lining copper tube |
| CN101862763B (en) * | 2010-06-18 | 2013-03-27 | 常州市联谊特种不锈钢管有限公司 | Production process of large-caliber thin-walled seamless stainless steel pipe |
| CN102363256B (en) * | 2011-06-16 | 2013-08-21 | 深圳市北科航飞生物医学工程有限公司 | A method of processing cobalt-base alloy superfine thin-walled tubes for stents |
| CN102626724B (en) * | 2012-04-19 | 2014-11-26 | 常熟市异型钢管有限公司 | Method for producing titanium alloy pipe |
| CN108517478B (en) * | 2018-04-04 | 2019-10-29 | 浙江久立特材科技股份有限公司 | A kind of manufacturing process of the small-bore accurate pipe of 718 alloy |
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2003
- 2003-04-03 CN CN 03109033 patent/CN1201878C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN1439465A (en) | 2003-09-03 |
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