WO2011093055A1 - Procédé de fabrication pour tuyau de petit diamètre à paroi mince - Google Patents

Procédé de fabrication pour tuyau de petit diamètre à paroi mince Download PDF

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Publication number
WO2011093055A1
WO2011093055A1 PCT/JP2011/000371 JP2011000371W WO2011093055A1 WO 2011093055 A1 WO2011093055 A1 WO 2011093055A1 JP 2011000371 W JP2011000371 W JP 2011000371W WO 2011093055 A1 WO2011093055 A1 WO 2011093055A1
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WO
WIPO (PCT)
Prior art keywords
pipe
thickness
tube
small
diameter
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Application number
PCT/JP2011/000371
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English (en)
Japanese (ja)
Inventor
拓也 花田
達也 奥井
Original Assignee
住友金属工業株式会社
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Filing date
Publication date
Application filed by 住友金属工業株式会社 filed Critical 住友金属工業株式会社
Publication of WO2011093055A1 publication Critical patent/WO2011093055A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C3/00—Profiling tools for metal drawing; Combinations of dies and mandrels
    • B21C3/02—Dies; Selection of material therefor; Cleaning thereof
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C3/00—Profiling tools for metal drawing; Combinations of dies and mandrels
    • B21C3/16—Mandrels; Mounting or adjusting same

Definitions

  • the present invention relates to a method for producing a small-diameter, thin-walled seamless steel pipe by drawing from a hot pipe-made base pipe. More particularly, the present invention relates to a method for manufacturing a small diameter thin walled tube that does not have internal streaks.
  • Standard-diameter thin-walled pipe A seamless steel pipe obtained by drawing a base pipe obtained by hot-rolling into a predetermined size by drawing, and the ratio of thickness / outer diameter (T / D) after drawing is 5 to 15%, an outer diameter of 20 to 30 mm, and a thickness of 1.0 to 3.5 mm.
  • a seamless steel pipe that is cold-finished is made by forming a solid steel slab into a hollow base pipe by hot pipe making by Mannesmann pipe manufacturing method or Eugene pipe manufacturing method, and then drawing the base pipe cold. Manufactured.
  • Mannesmann tube method Mannesmann is drilled in a steel slab, and a constant diameter or reduced diameter rolling is performed with a sizer or a reducer to form a raw pipe.
  • the obtained tube is subjected to cold drawing.
  • the main purposes of cold drawing are to improve the dimensional accuracy of the outer diameter, inner diameter, and wall thickness, to ensure mechanical strength, and to improve the inner surface smoothness. That is, the reduction of wrinkles on the inner surface of the steel pipe is one of the major purposes of the cold drawing process.
  • Seamless steel pipes finished by drawing have applications such as for plant piping and machine structures, and are sometimes used in automobiles as steel pipes for automobiles.
  • the seamless steel pipe is used as a pressure vessel and is used in a state in which a high-pressure gas is sealed. Therefore, wrinkles on the inner surface of the seamless pipe are not preferable.
  • the pressure vessel of the airbag is required to be small and light, a small-diameter thin-walled tube is used for the steel tube for the airbag.
  • the effect of removing the internal streak is larger as the thickness processing degree expressed by the following formula (1) is larger.
  • TD (T′ ⁇ T) / T ′ ⁇ 100 (1)
  • the thickness processing degree is TD (%)
  • the thickness of the steel pipe before drawing is T ′ (mm)
  • the thickness of the steel pipe after drawing is T (mm).
  • FIG. 1 is a schematic view showing a drawing process using a taper die and a semi-floating plug.
  • FIG. 1 shows a taper die 1, a plug 2 inserted into the inner surface of a blank pipe (steel pipe before drawing), and a blank pipe 3 to be drawn, in the direction indicated by the hatched arrow. By moving, it is drawn.
  • the taper die 1 guides the pipe material to the die exit side, so that the taper-shaped approach portion 1a in which the inner diameter of the die on the entry side is reduced, the bearing portion 1b having a constant inner diameter and determining the processing shape of the pipe material, And a side relief portion 1c.
  • the shape of the approach portion 1a of the taper die is defined by both angles ⁇ (°).
  • the semi-floating plug 2 is fixed at a processing position by a support rod 2c held at a fixed end (not shown), and has a taper portion 2a for preventing displacement of the plug as the raw pipe is thickened, and a finished inner diameter of the pipe. And a finishing portion 2b to be defined.
  • the shape of the tapered portion of the semi-floating plastic is defined by both angles ⁇ (°).
  • the tube 3 is reduced in diameter in accordance with the contact with the taper die approach portion 1a, and then further contacted with the taper portion 2a of the semi-floating plug to be thickened. Is done. Thereafter, the blank tube 3 is thickened by a tapered die bearing portion 1b and a semi-floating plug finishing portion 2b to be finished into a seamless steel pipe having a predetermined outer diameter and inner diameter.
  • ⁇ A frictional force acts on the semi-floating plug 2 in the drawing direction as the raw pipe is processed during drawing. Further, when the raw pipe is thickly processed by the tapered portion 2a and the tapered die approach portion 1a, a reaction force acts on the semi-floating plug 2 in the direction indicated by the white arrow in FIG.
  • the semi-floating plug 2 is fixed at the machining position by the support bar 2c.
  • the support bar 2c is elastically deformed by the frictional force, and the floating plug is displaced from the machining position. It causes drawing defects such as generation and breakage of the tube.
  • the component in the drawing direction of the reaction force is equal to the frictional force, and the support bar 2c suppresses elastic deformation.
  • Patent Document 1 proposes a drawing method that can stabilize the plug position.
  • both angles (die both angles) ⁇ (°) of the approach portion of the die and both angles (plug both angles) ⁇ (°) of the taper portion of the plug are the following (2) and (3 ) Satisfying the equation, the pulling direction component of the reaction force described above and the frictional force are balanced, so that the position of the plug can be prevented from shifting in the drawing direction, and the seizure of the blank tube to the die and the breakage of the blank tube Can be prevented.
  • the small-diameter thin-walled pipe obtained may have an internal stripe depending on the angle of the die even if the above equation (2) is satisfied. May remain.
  • the removal effect of the inner surface streak is higher as the wall thickness processing degree is larger. Therefore, in order to prevent the inner streak from remaining, it is conceivable to increase the thickness of the raw tube. If the thickness ratio between the thickness and the steel pipe wall thickness after drawing is too large, vibrations and breakage of the raw pipe occur during drawing, and stable drawing cannot be performed. For this reason, in the drawing process of a small-diameter thin wall tube, the thickness of the raw tube cannot be increased so much.
  • Patent Document 2 relates to the reduction of inner surface streaks in a thick-walled seamless steel pipe having a thickness / outer diameter (T / D) ratio of 20% or more, and is an oil-lubricated or chemical-coating-lubricated base pipe Has been proposed for drawing under the processing conditions that satisfy the conditional expression defined by the thickness processing degree and the die angle.
  • the thickness ratio before and after the drawing process does not increase so much even if the thickness of the raw pipe is increased. If the conditional expression is satisfied, good results can be obtained. However, in the case of a small-diameter thin-walled tube, as described above, since the thickness of the raw tube cannot be increased so much, even if the conditional expression described in Patent Document 2 is satisfied, depending on the die angle, inner surface streaks may remain. .
  • the pipe tube is drawn only with a taper die without using a plug, and a drawing test by “empty drawing” is performed, and the influence of both angles of the approach part of the taper die on the wall thickness of the pipe. confirmed.
  • FIG. 2 is a diagram showing the relationship between the thickness / outer diameter (T / D) ratio (%) and the thickness increase rate TW (%) when a small-diameter thin tube is obtained by emptying only with a taper die. . From FIG. 2, it can be confirmed that the thickness increase rate TW (%) is a positive value. From this test, it was found that the wall thickness was increased (thickened) by pulling out the small-diameter thin-walled tube using a taper die (empty drawing). Moreover, it turned out that the wall-thickening rate TW (%) increases by making both angles (alpha) of an approach part small.
  • the present inventors have obtained the following findings (a) to (c) based on the above test results.
  • the present invention has been completed based on the above findings and the results of the confirmation test described later, and the gist of the following (1) to (3) is a method for producing a small-diameter thin-walled tube:
  • a taper die having a tapered approach portion and a bearing portion for determining a drawing outer diameter as a processing die A method for producing a seamless steel pipe by drawing a small-diameter thin wall pipe using a plug inserted into an inner surface of a pipe that is drawn while being reduced in diameter by the taper die, A method for manufacturing a small-diameter thin-walled tube, wherein a taper die having both angles of 15 to 20 ° is used in the approach portion.
  • the method for producing a small-diameter thin-walled tube of the present invention has the following remarkable effects. (1) By drawing using a taper die and a plug, a small-diameter thin tube with excellent inner surface quality can be obtained by reducing inner surface streaks that occur during hot pipe manufacturing without increasing the thickness of the tube. Obtainable.
  • FIG. 1 is a schematic diagram showing a drawing process using a taper die and a semi-floating plug.
  • FIG. 2 is a diagram showing the relationship between the thickness / outer diameter (T / D) ratio (%) and the thickness increase rate TW (%) when a small-diameter thin tube is obtained by emptying only with a taper die.
  • FIG. 3 is a photograph of the inner surface properties of the pipe that was cut in the middle of the drawing process, and the pipe was cut.
  • FIG. 3A is a comparative example in which both angles of the approach portion of the taper die are 25 °.
  • FIG. 3B shows an example of the present invention in which both angles are 20 °.
  • FIG. 4 is a diagram showing the thickness ratio and the inner surface depth ratio at each position in the drawing direction of the pipe, with the pipe drawing process stopped in the middle and the pipe cut. ) Shows the wall thickness ratio at each position, and FIG. 4B shows the depth ratio of the inner surface reinforcement at each position.
  • the steel pipe that is the subject of the present invention is a small-diameter thin-walled pipe.
  • the small-diameter thin-walled pipe is a seamless steel pipe obtained by finishing a raw pipe obtained by hot pipe making into a predetermined dimension by drawing, and the thickness / outer diameter (T / D) after drawing.
  • the ratio is 5 to 15%
  • the outer diameter is 20 to 30 mm
  • the wall thickness is 1.0 to 3.5 mm.
  • the ratio of thickness / outer diameter (T / D) after drawing is 15% or the thickness exceeds 3.5 mm, the internal stripes can be reduced by the conventional drawing, and the small diameter thin wall of the present invention There is no need to use a tube manufacturing method.
  • the thickness / outer diameter (T / D) ratio after drawing is 5% or the thickness is less than 1.0 mm, sufficient strength as a pressure vessel for an airbag cannot be ensured.
  • the outer diameter after drawing is set to 20 to 30 mm based on the use of the steel pipe for airbag.
  • Small-diameter thin-walled pipes are made of various steel types such as Cr-Mo steel and carbon steel.
  • Cr-Mo steel When Cr-Mo steel is used, the inner pipes are likely to have internal striations, and the internal streaks are not removed even after drawing. It tends to remain. Therefore, it is preferable to use the method for producing a small-diameter thin tube of the present invention for drawing a small-diameter thin tube made of Cr—Mo steel.
  • the method for producing a small-diameter thin-walled tube according to the present invention includes a taper die having a tapered approach portion as a working die and a bearing portion for determining a drawing outer diameter, and is drawn while being reduced in diameter by the taper die.
  • both angles of the approach portion of the taper die are set to 15 to 20 °. From the results shown in FIG. 2, it can be seen that in the emptying of the small-diameter thin-walled tube, the thickness increase rate TW (%) increases when both angles of the approach portion are reduced. For this reason, in the drawing process using a plug, by reducing both angles of the approach part, it is possible to increase the thickness of the raw pipe (drawn pipe) at the approach part. Can increase the degree.
  • the approach portion since the thickness once increases, the thickness processing degree can be substantially secured in the processing at the bearing portion, and the inner surface streak of the obtained seamless steel pipe can be reduced.
  • both angles of the approach part of the taper die exceed 20 °, the thickness increase rate TW due to the taper die will decrease, so it is not possible to secure the wall thickness processing in the bearing part, and the obtained seamless steel pipe has no internal reinforcement. Remains.
  • both angles of the approach portion are less than 15 °, the contact distance between the approach portion and the raw pipe increases, and therefore vibration due to poor lubrication is likely to occur. In this case, the inner surface quality of the obtained seamless steel pipe deteriorates.
  • various plugs such as a cylindrical plug, a semi-floating plug, and a floating plug can be used as the plug, but it is preferable to use a semi-floating plug.
  • a semi-floating plug as the plug, the plug can be stably disposed at the processing position, and drawing defects can be suppressed.
  • both angles of the tapered portion satisfy the following expression (3). ⁇ -10 ⁇ ⁇ ⁇ ⁇ -3 (3)
  • both angles ⁇ (°) of the approach portion of the taper die are defined as both angles ⁇ (°) of the taper portion of the plug.
  • the small-diameter thin-walled tube used for the airbag is used in a state in which high-pressure gas is sealed, and therefore, internal streaks are not preferable.
  • the method for manufacturing a small-diameter thin-walled tube of the present invention it is possible to substantially secure the thickness processing degree without increasing the thickness of the raw tube so much. The inner surface streak can be removed.
  • the test of obtaining a small-diameter thin wall tube by drawing a hot-tubed raw tube by the method for producing a small-diameter thin wall tube of the present invention was conducted to verify the effect of the present invention.
  • Both angles of the approach portion of the taper die were set to 15 ° in the present invention example 1, 20 ° in the present invention example 2, and 25 ° in the comparative example 1. Further, both angles of the tapered portion of the floating plug were 10 ° in the present invention example 1, 15 ° in the present invention example 2, and 20 ° in the comparative example 1.
  • the inner surface properties of the drawn pipes were confirmed visually. Furthermore, in Invention Example 2 and Comparative Example 1, the pipe drawing process was stopped in the middle of the process, and after the pipe was cut, the thickness of the pipe and the depth of the inner surface streak were measured at a plurality of positions in the drawing direction. The wall thickness ratio and the depth ratio of the internal muscles were calculated.
  • the thickness ratio refers to a value represented by T / T ′, where T is the measured thickness of the tube and T ′ is the thickness of the raw tube.
  • the depth ratio of the inner surface streak is a value represented by A / A ′, where A is the measured depth of the inner surface streak and A ′ is the depth of the inner surface streak of the raw tube. That means.
  • FIG. 3 is a photograph of the inner surface properties of the pipe that was cut in the middle of the drawing process, and the pipe was cut.
  • FIG. 3A is a comparative example in which both angles of the approach portion of the taper die are 25 °.
  • FIG. 3B shows an example of the present invention in which both angles are 20 °.
  • 3 (a) and 3 (b) show a cut surface 3a of the drawn tube and a tube inner surface 3b.
  • the contact start position 3d with the approach portion of the taper die and the contact start position 3e with the finish portion of the floating plug are shown. Is indicated by a white dotted line.
  • a portion surrounded by a white imaginary line is an inner surface streak.
  • Example 2 of the present invention it was confirmed from FIG. 3 (b) that there was no streak on the inner surface 3b after drawing using a taper die having both angles of the approach portion of 20 °.
  • FIG. 4 is a diagram showing the wall thickness ratio and the inner surface muscle depth ratio at each position in the drawing direction of the pipe with respect to what the pipe drawing process is stopped in the middle of the process as in FIG.
  • FIG. 4A shows the thickness ratio at each position
  • FIG. 4B shows the inner surface depth ratio at each position.
  • the horizontal axes in FIGS. 4A and 4B indicate the distance from the contact position of the plug to the measurement position.
  • the approach side of the taper die is negative ( ⁇ ), and the relief side of the taper die is positive (+).
  • the wall thickness ratio before the bearing portion is larger in the present invention example 2 in which both angles of the approach portion are 20 ° than in Comparative Example 1 in which both angles of the approach portion of the taper die are 25 °. It was confirmed that it was large, that is, the wall thickness was increased more in the approach part. Therefore, it was confirmed that the substantial thickness processing degree in the bearing portion was increased.
  • Example 4B in Comparative Example 1 in which both angles of the approach portion are 25 °, the depth of the inner surface streak is reduced by the drawing process, but the inner surface streak remains after the drawing process. was confirmed. On the other hand, in Example 2 of the present invention in which both angles of the approach portion were 20 °, it was confirmed that the inner surface streak was removed after the drawing process.
  • the manufacturing method of the small-diameter thin wall tube of the present invention the amount of increase in the raw tube is increased in the approach part, and in the subsequent wall thickness processing, the wall thickness processing degree is increased according to the increase in the wall thickness increase in the approach part.
  • the method for producing a small-diameter thin-walled tube of the present invention has the following remarkable effects. (1) By drawing using a taper die and a plug, a small-diameter thin tube with excellent inner surface quality can be obtained by reducing inner surface streaks that occur during hot pipe manufacturing without increasing the thickness of the tube. Obtainable. (2) When the obtained small-diameter thin-walled tube is applied to a pressure vessel that constitutes an airbag, it has excellent resistance to bursting because it has no inner surface streaks. Therefore, according to the manufacturing method of the present invention, it is possible to provide a small-diameter thin-walled tube suitable for a pressure vessel used for an automobile airbag.
  • taper dies 1a. Approach section, 1b. Bearing part, 1c. 1. escape part, Semi-floating plug, 2a. Taper, 2b. Finishing part, 2c. 2. a support rod; Element tube, 3a. Raw tube cut surface, 3b. Inner surface of the tube 3c. Inner muscle, 3d. Contact start position with taper die, 3e. Contact start position with floating plug, ⁇ . Both angles of approach part, ⁇ . Both corners of taper

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Metal Extraction Processes (AREA)

Abstract

La présente invention concerne un procédé de fabrication pour un tuyau d'acier sans soudure selon lequel un tuyau de petit diamètre à paroi mince est étiré au moyen d'une matrice conique (1), qui est utilisée comme matrice de travail et est munie d'une partie d'approche (1a) qui présente une forme conique, et une partie portante (1b) qui délimite le diamètre extérieur lors du processus d'étirage, et un poinçon (2), qui est introduit dans la surface intérieure d'un tuyau (3) en cours d'étirage tandis que le diamètre du tuyau est réduit par la matrice conique (1). Grâce à l'utilisation de la matrice conique (1) dans laquelle la partie d'approche (1a) forme un angle (α) de 15 à 20°, il est possible de réduire les stries sur la surface intérieure du tuyau qui se produisent lors d'un processus de fabrication à chaud de tuyaux sans accroître l'épaisseur du tuyau de base, permettant ainsi d'obtenir un tuyau de petit diamètre à paroi mince avec une grand qualité de surface intérieure. Dans le procédé de fabrication selon l'invention pour un tuyau de petit diamètre à paroi mince, il est préférable que le poinçon (2) soit un poinçon semi-flottant muni d'une partie de finition (2b) qui ajuste le diamètre intérieur fini du tuyau et d'une partie conique (2a), qui est adjacente à la partie de finition.
PCT/JP2011/000371 2010-01-28 2011-01-25 Procédé de fabrication pour tuyau de petit diamètre à paroi mince WO2011093055A1 (fr)

Applications Claiming Priority (2)

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JP2010016551A JP2011152576A (ja) 2010-01-28 2010-01-28 小径薄肉管の製造方法
JP2010-016551 2010-01-28

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WO2011093055A1 true WO2011093055A1 (fr) 2011-08-04

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103624102A (zh) * 2013-12-04 2014-03-12 海盐三鑫钢管有限公司 冷拔油缸管的加工方法
CN103801575A (zh) * 2014-02-08 2014-05-21 芜湖鑫力管道技术有限公司 不锈钢复合管冷拔专用模具
US10850584B2 (en) 2016-06-07 2020-12-01 Beijingwest Industries Co., Ltd. Damper housing and a method for manufacturing the damper housing

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006272396A (ja) * 2005-03-29 2006-10-12 Sumitomo Metal Ind Ltd 管の引抜加工用工具及びこれを用いた管の製造方法

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0760335A (ja) * 1993-08-25 1995-03-07 Sumitomo Metal Ind Ltd 鋼管の引抜加工方法
JPH1161301A (ja) * 1997-08-08 1999-03-05 Tokin Corp ＴｉＮｉ系形状記憶合金管及びその製造方法

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006272396A (ja) * 2005-03-29 2006-10-12 Sumitomo Metal Ind Ltd 管の引抜加工用工具及びこれを用いた管の製造方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103624102A (zh) * 2013-12-04 2014-03-12 海盐三鑫钢管有限公司 冷拔油缸管的加工方法
CN103801575A (zh) * 2014-02-08 2014-05-21 芜湖鑫力管道技术有限公司 不锈钢复合管冷拔专用模具
US10850584B2 (en) 2016-06-07 2020-12-01 Beijingwest Industries Co., Ltd. Damper housing and a method for manufacturing the damper housing

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JP2011152576A (ja) 2011-08-11

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