CN111069445B - Wall thickness control method for expanding and drawing copper pipe - Google Patents
Wall thickness control method for expanding and drawing copper pipe Download PDFInfo
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- 238000000034 method Methods 0.000 title claims abstract description 31
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 title claims abstract description 15
- 229910052802 copper Inorganic materials 0.000 title claims abstract description 15
- 239000010949 copper Substances 0.000 title claims abstract description 15
- 229910000570 Cupronickel Inorganic materials 0.000 claims abstract description 21
- 238000004513 sizing Methods 0.000 claims abstract description 14
- 238000000137 annealing Methods 0.000 claims abstract description 12
- 238000004364 calculation method Methods 0.000 claims description 8
- 238000012937 correction Methods 0.000 claims description 4
- 230000008859 change Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 9
- 238000013461 design Methods 0.000 abstract description 8
- 230000008569 process Effects 0.000 abstract description 7
- 238000009826 distribution Methods 0.000 abstract 1
- 239000002994 raw material Substances 0.000 abstract 1
- 230000009471 action Effects 0.000 description 14
- 238000005259 measurement Methods 0.000 description 10
- 238000012360 testing method Methods 0.000 description 10
- 230000000052 comparative effect Effects 0.000 description 8
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000009467 reduction Effects 0.000 description 2
- 238000005097 cold rolling Methods 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005489 elastic deformation Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
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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
- B21D39/00—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders
- B21D39/08—Tube expanders
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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
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
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Abstract
The invention relates to a wall thickness control method for expanding and drawing a copper pipe. The method comprises the steps of firstly determining the specification of a tube blank raw material and the diameter of an inner mold sizing belt, then calculating the wall thickness of the tube blank after being drawn without an outer mold by using an empirical formula, and finally determining the inner diameter of the outer mold sizing belt according to the wall thickness without the outer mold and the target wall thickness of the current pass. The invention relates to a method for calculating the wall thickness of a tube blank drawn without an outer die and a method for calculating the inner diameter of an outer die bearing belt during diameter-expanding drawing of an inner die and an outer die according to a target thickness, which are summarized by years of production experience of an inventor, are used as direct basis for designing a diameter-expanding drawing die and are used for accurately controlling the wall thickness of the tube drawn in each pass, the error rate is lower than 0.5 percent, direct basis can be provided for the deformation rate distribution of the diameter-expanding drawing pass of a large-caliber cupronickel tube, the design of an annealing process and the design of the drawing die, and the.
Description
Technical Field
The invention relates to a copper pipe expanding process, in particular to a wall thickness control method for expanding and drawing a copper pipe.
Background
The large-caliber white copper pipe is a key structural product required in the field of ocean engineering, and at present, only a few domestic enterprises have the production capacity of the product. The pipe for ocean engineering has high requirements on corrosion resistance, air tightness, weldability and the like, so that the white copper pipe product needs to have higher precision in the aspects of shape and size. The large-diameter seamless white copper pipe is generally produced by adopting an extrusion-cold rolling-drawing technology. Generally, the final forming for producing small-caliber pipes generally adopts common fixed short core print, long core bar or moving core print for reducing diameter, and for large-caliber seamless pipes, the diameter expanding and drawing technology is the best mode for realizing the diameter expanding and wall reducing. The production process of the large-diameter cupronickel tube is subjected to a plurality of processes, mainly comprising extrusion cogging, cold rolling, multi-pass expanding and drawing, annealing, finishing, straightening, flaw detection and the like, wherein the expanding and drawing is a key process influencing the size and shape precision of a product. The principle diagram of expanding and drawing is shown in FIG. 1.
The diameter expanding drawing process is divided into two types, one is diameter expanding drawing without an external die, and the other is diameter expanding drawing with an external die. The drawing without an external die is a processing method with lower precision, because the die only controls the inner diameter of the tube blank to be enlarged when the tube blank is drawn without the external die, the outer diameter direction of the tube blank is freely deformed, the wall thickness of the tube blank is changed, parameters such as the deformation amount after drawing are influenced by various factors such as the size of the tube blank, boundary friction, alloy state, resilience and the like, and the accurate prediction and control are generally difficult. In the expanding and drawing process with the external die, under the simultaneous action of the external die and the core die (internal die), the complete control of the internal diameter, the external diameter and the wall thickness can be theoretically realized, however, in the actual production, the design of the external die dimension is difficult to accurately grasp due to the unknown relation among the specification of the specific internal/external die and the internal diameter and the wall thickness of the pipe, so that the technical problem of inaccurate control of the wall thickness of the pipe after drawing is easily caused. If the inner diameter of the outer die working belt (the inner diameter of the bearing belt) is too large, the outer wall of the tube blank cannot be contacted, and the effect of limiting the wall thickness cannot be achieved; if the inner diameter of the outer die working belt (the inner diameter of the bearing belt) is too small, the drawing force and the nonuniformity and instability of deformation can be obviously increased due to too large diameter reduction deformation rate, pipe breakage can be caused in serious cases, the outer surface of a product can be damaged, and the surface quality of the pipe after diameter reduction drawing is seriously influenced.
Therefore, a set of feasible external mold design scheme is needed to be provided for reasonably designing the external mold size, so that the external mold size can be effectively controlled, the wall thickness of a product can be effectively controlled, the drawing deformation of a copper pipe is more uniform, the residual stress is reduced, the drawing force cannot be obviously increased, the production difficulty is reduced, and the smooth production of a large-caliber thin-wall white copper pipe product with high dimensional precision and high surface quality is ensured.
Disclosure of Invention
The invention aims to provide a wall thickness control method for copper pipe expanding and drawing in view of the prior art, and particularly aims to provide a wall thickness control method for copper pipe expanding and drawing in view of expanding and drawing with an external mold.
The technical scheme adopted by the invention for solving the problems is as follows: a wall thickness control method for copper pipe expanding and drawing is characterized in that an inner die and an outer die are jointly acted on a pipe blank to expand and draw the pipe blank, wherein the inner die is located inside the pipe blank, the outer die is located outside the pipe blank, a sizing belt of the outer die and a sizing belt of the inner die are matched with each other inside and outside to form a forming annular space, and according to the outer diameter of the sizing belt of the inner die, the initial specification and the target wall thickness of the pipe blank, the inner diameter D of the sizing belt of the outer die is calculated:
D＝M+(2d/M-k)×t1+k×t2(mm) (1)
in the formula (1), M is the outer diameter of the inner die bearing belt, and the unit is mm; d is the initial inner diameter of the tube blank, and the unit is mm; t is t1The thickness of the pipe wall obtained by the expanding and drawing without the outer die, namely the inner die is independently adopted, and the unit is mm, which is determined by the formula (2); t is t2Target wall thickness in mm; k is a wall thickness variation parameter before and after diameter change and is determined by the formula (3);
t1＝[1+ln(M/d)]×t0+C (2)
in the formula (2), C is a correction coefficient and has a value range of-0.1 mm to 0.2 mm;
k＝1-(t2-t0)/t0 (3)
in the formula (3), t0Initial wall thickness of tube blank, t2Is the target wall thickness.
Preferably, in the formula (2), the value of the correction coefficient C is determined with reference to (M-d):
(M-d)<10mm，C＝-0.1mm；
10≤(M-d)<20mm，C＝0mm；
20≤(M-d)<30mm，C＝0.1mm；
(M-d)≥30mm，C＝0.2mm。
the control method for the diameter-expanding drawing wall thickness is limited by the specification of the tube blank, the target specification and the material of the tube blank, and shows a reasonable application range. The application scope is as follows: the calculation methods of the formula (1) and the formula (2) are suitable for the initial wall thickness d of 220mm-320mm and the initial wall thickness t07.0mm-15.0mm of tube blank, 255mm-355mm of inner die bearing external diameter M and target wall thickness t2Is 6.0mm-15.0 mm.
Preferably, the pipe blank is annealed before the expanding drawing, and the expanding drawing is performed on the pipe blank in an annealed state.
Preferably, the method is suitable for expanding and drawing the cupronickel blank in an annealing state. In particular to an annealed BFe10-1-1 cupronickel tube blank.
Compared with the prior art, the invention has the advantages that: the invention relates to a wall thickness calculation and control method for expanding and drawing a copper pipe, which is summarized by combining years of practical experience of the inventor based on the mechanical principle of metal plastic deformation, and forms empirical formulas (1) and (2). When expanding and drawing, the metal in the plastic deformation area is in a more complex three-dimensional stress strain state, meanwhile, the non-plastic deformation area is in a remarkable elastic deformation state, and the drawing force is transmitted to the plastic deformation area in the die gap through the deformed tube blank. When the diameter expansion drawing is carried out without an external die, the die only controls the inner diameter expansion of the tube blank, the outer diameter direction of the tube blank is free plastic deformation, parameters such as the wall thickness change rate, the deformation amount after drawing and the like are influenced by various factors such as the size of the tube blank, boundary friction, alloy state and the like, and the accurate prediction and control are generally difficult. In the diameter expanding drawing with an external mold, under the simultaneous action of the external mold and the core mold (internal mold), the complete control of the internal diameter, the external diameter and the wall thickness can be theoretically realized, however, in the actual production, the design of the external mold size is difficult to be accurately mastered due to the lack of the specific quantitative corresponding relation among the internal/external mold size, the internal diameter of the tube blank and the wall thickness, and the external mold size is usually designed only by experience, which easily causes the technical problem of inaccurate control of the tube wall thickness after the drawing. The error rate between the wall thickness of the pipe after drawing and the expected target size is 1-5%.
The invention has the advantages that under the guidance of a mechanical theory, the inventor combines finite element numerical simulation and production experience summarization to establish the quantitative relationship among the dimensions of the inner/outer dies for expanding drawing, the inner diameter of the tube blank and the wall thickness, and can conveniently and accurately determine the inner diameter dimension of the outer die for drawing in each pass, so that the error rate of the wall thickness is less than 0.5 percent. Compared with the original die design method, the method provided by the invention has the advantages that the die design efficiency is obviously improved, the error rate of the tube wall thickness after expanding and drawing is lower than 0.5%, and the expanding and drawing precision of the product is obviously improved.
Drawings
FIG. 1 is a schematic diagram of expanding and drawing by using the combined action of an inner mold and an outer mold;
in the figure, 1 chuck, 2 plug core, 3 outer die, 4 tube blank, 5 lining core, 6 core bar and 7 push rod.
Detailed Description
The present invention will be described in further detail with reference to examples. The following examples, given by way of illustration, are intended to illustrate the invention and are not to be construed as limiting the invention.
The following method is a calculation method of tube blank wall thickness during expanding and drawing without external mold
Example 1
The specification is that the inner diameter is phi 220mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (7.0 mm, the actual size of the pipe blank is deviated, therefore, when the practical formula is used for calculation, the pipe blank needs to be measured again, and the practical measurement value is taken as the standard) is subjected to an expanding drawing test without an external mold under the action of a core mold with the diameter of a bearing diameter phi 255mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core mold used for the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Example 2
The specification is that the inner diameter is phi 260mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard), the diameter expanding drawing test without an external mold is carried out under the action of a core mold with the diameter phi of 275mm of the bearing diameter, the initial wall thickness of the pipe blank is measured, the bearing diameter of the core mold used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Example 3
The specification is that the inner diameter is phi 260mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard), the diameter expanding drawing test without an external mold is carried out under the action of a core mold with the diameter of a bearing diameter phi 285mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core mold used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Example 4
The specification is that the inner diameter is phi 260mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the actual size of the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard), an external mold-free expanding drawing test is carried out under the action of a core mold with the diameter of a bearing diameter phi 285mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core mold used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Example 5
The specification is that the inner diameter is phi 320mm and the wall thickness is t09.5mm annealed BFe10-1-1 cupronickel tube blank (the actual size of the tube blank is deviated, therefore, when the tube blank is calculated by an empirical formula, the tube blank needs to be measured again, and the actual measurement value is taken as the standard), an external-die-free expanding and drawing test is carried out under the action of a core die with a bearing diameter phi of 355mm, and the measured value is measuredMeasuring the initial wall thickness of the tube blank, determining the diameter of the bearing of the mandrel used in the drawing, and calculating the predicted value of the wall thickness by using an empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Example 6
The specification is that the inner diameter is phi 260mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard), an external mold-free expanding drawing test is carried out under the action of a core mold with the diameter of a bearing phi 275mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core mold used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Comparative example 1
The specification is that the inner diameter is phi 220mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard) is subjected to an expanding drawing test without an outer die under the action of a core die with the diameter of a bearing phi 245mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core die used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Comparative example 2
The specification is that the inner diameter is phi 260mm and the wall thickness is t0The annealing state BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, therefore, when the pipe blank is calculated by an empirical formula, the pipe blank needs to be measured again, and the actual measurement value is taken as the standard), the diameter expanding drawing test without an external mold is carried out under the action of a core mold with the diameter of a bearing diameter phi 375mm, the initial wall thickness of the pipe blank is measured, the diameter of the bearing of the core mold used in the drawing is determined, and the predicted value of the wall thickness is calculated by the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Comparative example 3
The specification is that the inner diameter is 270mm and the wall thickness is t0Annealed BFe10-1 at 6.5mm-1 blank of cupronickel tube (the actual size of the blank tube is deviated, therefore, when the blank tube is calculated by using empirical formula, the blank tube needs to be measured again, based on the actual measurement value), an external-die-free expanding drawing test is carried out under the action of a core die with a diameter phi 285mm, the initial wall thickness of the blank tube is measured, the diameter of the bearing of the core die used in the drawing is determined, and the predicted value of the wall thickness is calculated by using empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
Comparative example 4
The specification is that the inner diameter is 270mm and the wall thickness is t0The method comprises the steps of carrying out an external-die-free expanding drawing test on a 15.5mm annealed BFe10-1-1 cupronickel pipe blank (the actual size of the pipe blank is deviated, so that the pipe blank needs to be measured when an empirical formula is used for calculation, and the actual measurement value is taken as the standard) under the action of a core die with a bearing diameter phi 285mm, measuring the initial wall thickness of the pipe blank, determining the bearing diameter of the core die used for the drawing, and calculating the predicted value of the wall thickness by using the empirical formula (2) of the invention. And measuring the real wall thickness value after drawing.
The wall thickness calculated value t of the no-external-die drawing obtained in the above examples and comparative examples1And the measured value t of the wall thickness after drawingcThe error rate η is calculated using the following formula, as set forth in the table below:
η＝∣tc-t1∣/t1
the results are recorded in table 1:
TABLE 1 example and comparative example Processes and results
As can be seen from Table 1, in examples 1 to 6, by using the calculation method (formula 2) for the diameter-expanding and drawing wall thickness without the external die, the wall thickness value after diameter-expanding and drawing can be accurately predicted in the range of the external diameter phi 255mm to phi 355mm of the core die of the annealed BFe10-1-1 white copper pipe blank with the initial wall thickness range of 7.0mm to 15.0mm, and the error rate of the wall thickness value is less than 0.7%. In comparative examples 1 to 2, the outer diameter of the mandrel sizing belt is too small or too large, and in comparative examples 3 to 4, the wall thickness is too thick or too thin, so that the application range of the invention is exceeded, and the error rate is larger and reaches 1.8 to 2.6 percent.
In conclusion, by adopting the diameter-expanding drawing without the outer die, the control precision of the wall thickness of the tube blank is related to the outer diameter of the mandrel bearing, the initial wall thickness of the tube blank and the initial inner diameter, and in an application range, the empirical formula (2) of the invention can be used for guiding the determination of the outer diameter of the mandrel bearing used during the diameter-expanding drawing without the outer die or can be used for accurately pre-judging the target wall thickness after the diameter-expanding drawing of the tube blank.
Wall thickness control method for expanding and drawing under combined action of inner mold and outer mold at lower part
Example 7
In the embodiment, the inner die and the outer die are jointly used for expanding and drawing the tube blank. The tube blank of annealed BFe10-1-1 cupronickel with the inner diameter phi of 290mm and the wall thickness of 8.80mm is subjected to one-time expanding and drawing to form a tube with the inner diameter phi of 305mm and the wall thickness of 8.30 mm. In this embodiment, the following steps are adopted to determine the sizing diameters of the core mold and the outer mold, specifically, the determination of the outer diameter of the sizing band of the core mold and the inner diameter of the sizing band of the outer mold is adopted:
1. measuring the initial diameter d and the initial wall thickness t of the tube blank0Determining the diameter M of the core die drawn in the current pass and the target wall thickness t2Respectively as follows: d is 290 mm; t is t0＝8.80mm；M＝305mm；t2＝8.30mm；
2. The empirical formula (formula 2) of wall thickness control is utilized to calculate the wall thickness t of the tube blank after expanding and drawing under the condition of no external mold1(C in this example takes a value of 0):
t1＝[1+ln(M/d)]×t0+C＝8.36mm
3. designing the inner diameter of the outer mold sizing belt:
determining the external die bearing internal diameter D according to the formulas (1) and (3):
k＝1-(t2-t0)/t0＝0.943
D＝M+(2d/M-k)×t1+k×t2＝320.8mm
4. after determining that the outer diameter of the drawing core die is phi 305mm and the inner diameter of the external die bearing is phi 320.8mm, processing the die and performing an expanding drawing experiment on the three annealed tube blanks; firstly measuring the actual wall thickness, then measuring the wall thickness after drawing, comparing the actual wall thickness t after drawing with the target wall thickness of 8.30mm, and calculating the deviation ratio eta of the actual wall thickness and the expected wall thickness by the following formula:
η＝∣t-8.30∣/8.30
and is recorded in table 2.
TABLE 2 wall thickness and deviation of expanded drawn tube
As can be seen from Table 2, although the thickness of the drawn front wall of the tube blank has a certain deviation from the nominal size, the deviation ratio of the wall thickness of the tube blank from the wall thickness of the expected design can be controlled below 0.5 percent after the diameter expanding drawing with external die limitation. The diameter-expanding drawing die designed by the invention is qualified and can be put into production.
Although preferred embodiments of the present invention have been described in detail hereinabove, it should be clearly understood that modifications and variations of the present invention are possible to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A wall thickness control method for expanding and drawing a copper pipe is characterized by comprising the following steps: an inner die and an outer die are jointly acted on a tube blank to perform expanding and drawing on the tube blank, wherein the inner die is positioned inside the tube blank, the outer die is positioned outside the tube blank, a sizing belt of the outer die and a sizing belt of the inner die are matched inside and outside to form a forming annular gap, and the forming annular gap is formed according to the outer diameter M of the sizing belt of the inner die, the initial inner diameter d of the tube blank and the initial wall thickness t0And target wall thickness t2And calculating the inner diameter D of the bearing of the outer die by adopting the following calculation formula:
D＝M+(2d/M-k)×t1+k×t2(mm) (1)
in the formula (1), M is the outer diameter of the inner die bearing belt, and the unit is mm; d is the initial inner diameter of the tube blank, and the unit is mm; t is t1Without external die for expanding diameterDrawing, namely, independently adopting the inner die to expand and draw the obtained pipe wall thickness, wherein the unit is mm and is determined by the formula (2); t is t2Target wall thickness in mm; k is a wall thickness variation parameter before and after diameter change and is determined by the formula (3);
t1＝[1+ln(M/d)]×t0+C (2)
in the formula (2), C is a correction coefficient and has a value range of-0.1 mm to 0.2 mm;
k＝1-(t2-t0)/t0 (3)
in the formula (3), t0Initial wall thickness of tube blank, t2Is the target wall thickness.
2. The method for controlling the wall thickness of the copper pipe in expanding and drawing according to claim 1, wherein: in the formula (2), the value of the correction coefficient C is determined with reference to (M-d):
(M-d)<10mm，C＝-0.1mm；
10≤(M-d)<20mm，C＝0mm；
20≤(M-d)<30mm，C＝0.1mm；
(M-d)≥30mm，C＝0.2mm。
3. the method for controlling the wall thickness of the copper pipe in expanding and drawing according to claim 1, wherein: the calculation methods of the formula (1) and the formula (2) are suitable for the initial inner diameter d of 220mm-320mm and the initial wall thickness t07.0mm-15.0mm of tube blank, 255mm-355mm of inner die bearing external diameter M and target wall thickness t2Is 6.0mm-15.0 mm.
4. The method for controlling the wall thickness of the copper pipe in expanding and drawing according to claim 1, wherein: and annealing the tube blank before the expanding and drawing, and performing the expanding and drawing on the tube blank in an annealed state.
5. The method for controlling the wall thickness of the copper pipe in expanding and drawing according to claim 1, wherein: the method is suitable for expanding and drawing the white copper pipe blank in an annealing state.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09103819A (en) * | 1995-10-09 | 1997-04-22 | Nippon Light Metal Co Ltd | Pipe manufacturing method with excellent shape accuracy by drawing and tool for drawing |
| WO2001054839A1 (en) * | 2000-01-28 | 2001-08-02 | Schmittersysco Gmbh | Method and forming tool for the production of cylindrical tubes by extrusion |
| CN1406681A (en) * | 2001-08-30 | 2003-04-02 | 隆昌山川精密焊管有限责任公司 | Cold drawing precisive pipe for electrically welding magneto casing of car |
| CN1744956A (en) * | 2003-04-11 | 2006-03-08 | 杰富意钢铁株式会社 | Manufacturing method and manufacturing apparatus of high dimensional precision tube |
| CN102632094A (en) * | 2012-04-24 | 2012-08-15 | 西北有色金属研究院 | Method for improving surface quality of titanium and titanium alloy pipes and drawing die |
| JP2013094812A (en) * | 2011-10-31 | 2013-05-20 | Nippon Steel & Sumitomo Metal Corp | Cold-drawing apparatus and method of manufacturing metal pipe |
| CN108971247A (en) * | 2018-09-10 | 2018-12-11 | 江阴市洪腾机械有限公司 | A kind of combination cold drawing die reducing thickness of steel pipe difference |
-
2019
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Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09103819A (en) * | 1995-10-09 | 1997-04-22 | Nippon Light Metal Co Ltd | Pipe manufacturing method with excellent shape accuracy by drawing and tool for drawing |
| WO2001054839A1 (en) * | 2000-01-28 | 2001-08-02 | Schmittersysco Gmbh | Method and forming tool for the production of cylindrical tubes by extrusion |
| CN1406681A (en) * | 2001-08-30 | 2003-04-02 | 隆昌山川精密焊管有限责任公司 | Cold drawing precisive pipe for electrically welding magneto casing of car |
| CN1744956A (en) * | 2003-04-11 | 2006-03-08 | 杰富意钢铁株式会社 | Manufacturing method and manufacturing apparatus of high dimensional precision tube |
| JP2013094812A (en) * | 2011-10-31 | 2013-05-20 | Nippon Steel & Sumitomo Metal Corp | Cold-drawing apparatus and method of manufacturing metal pipe |
| CN102632094A (en) * | 2012-04-24 | 2012-08-15 | 西北有色金属研究院 | Method for improving surface quality of titanium and titanium alloy pipes and drawing die |
| CN108971247A (en) * | 2018-09-10 | 2018-12-11 | 江阴市洪腾机械有限公司 | A kind of combination cold drawing die reducing thickness of steel pipe difference |
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