KR101790100B1 - Manufacturing method of multi-layered pipe for seamless steel pipe with low weight and high strength - Google Patents

Manufacturing method of multi-layered pipe for seamless steel pipe with low weight and high strength Download PDF

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Publication number
KR101790100B1
KR101790100B1 KR1020150110747A KR20150110747A KR101790100B1 KR 101790100 B1 KR101790100 B1 KR 101790100B1 KR 1020150110747 A KR1020150110747 A KR 1020150110747A KR 20150110747 A KR20150110747 A KR 20150110747A KR 101790100 B1 KR101790100 B1 KR 101790100B1
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South Korea
Prior art keywords
pipe
steel pipe
diameter
molding
forming
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KR1020150110747A
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Korean (ko)
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KR20170017188A (en
Inventor
홍성박
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홍성박
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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
    • B21D39/04—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes with tubes; of tubes with rods
    • 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
    • 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
    • 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
    • B21D39/04—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes with tubes; of tubes with rods
    • B21D39/048—Application of procedures in order to connect objects or parts, e.g. coating with sheet metal otherwise than by plating; Tube expanders of tubes with tubes; of tubes with rods using presses for radially crimping tubular elements

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

Abstract

The present invention provides a method for manufacturing a weight reduction type multi-tube for forming high strength non-welded steel pipe. According to the method of manufacturing a multi-pipe for molding a heavy weight type high strength non-welded steel pipe according to the present invention, a plurality of steel pipes are pressed and joined together by a drawing process or a cold rolling process using a mold and a mandrel, It is possible to easily and easily manufacture a high strength non-steel pipe without increasing the thickness of the steel pipe, thereby reducing the weight of the high-strength pipe and reducing the manufacturing cost.
A method for manufacturing a weight reduction type high strength multimetal steel pipe for forming a multi-pipe according to the present invention is a method for manufacturing a heavy metal pipe having a molding hole portion 11 having an inner diameter equal to an outer diameter of an outer pipe (2) 10); The mandrel 20 having the molding surface portion 25a having the same outer diameter as the inner diameter of the inner tube 3 constituting the inner circumferential surface of the multi-gravity steel pipe 1 passes through the molding hole portion 11 of the mold 10 A mandrel positioning step disposed inside the inner tube material 3 '; An outer tube material 2 'and an inner tube material 3', which are formed into the outer tube 2 and the inner tube 3 of the multi-gravity steel pipe 1, are subjected to either one of a drawing process and a cold rolling process (2 ') in the course of passing through the molding hole portion (11) of the mold (10), and the multi-walled steel pipe (1) The outer diameter of the outer pipe 2 of the multifilamentary steel pipe 1 is reduced to the outer diameter of the outer pipe 2 and the molten metal passes through the molding surface portion 25a of the mandrel 20 positioned in the molding hole portion 11 of the mold 10 So that the inner diameter of the inner pipe material 3 'is reduced to the inner diameter of the inner pipe 3 of the multi-pipe type steel pipe 1.

Description

Technical Field [0001] The present invention relates to a method of manufacturing a multi-layer pipe for forming a high strength non-massive steel pipe,

More particularly, the present invention relates to a method for manufacturing a multi-tube for forming a heavy weight type high strength non-welded steel pipe, and more particularly, to a method for manufacturing a multi- The present invention relates to a method of manufacturing a multi-pipe for molding a high strength non-welded steel pipe, which can easily and easily manufacture a high strength non-welded steel pipe without increasing the thickness of the pipe, thereby reducing the weight of the high- will be.

The pipe for conveying the high-pressure gas or the high-pressure fluid is made of a high-strength material capable of withstanding high pressure, or the thickness thereof is increased to increase the strength. Regarding the technique of manufacturing the high strength pipe by improving the physical properties of the pipe material, Korean Patent Registration No. 10-0361471 entitled "Ultra high strength line pipe excellent in low temperature toughness and manufacturing method thereof" There is a problem in that the manufacturing process is cumbersome and the pipe manufacturing cost is increased.

Further, in the technique of increasing the pipe strength by increasing the pipe thickness, there is a problem that the pipe weight increases, the material cost increases, and the pipe installation becomes difficult.

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Korean Registered Patent Publication No. 10-0361471 "Ultra-high strength line pipe excellent in low temperature toughness and manufacturing method thereof"

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a method of manufacturing a steel pipe for a steel pipe, It is possible to manufacture a high strength non-steel pipe easily and easily without increasing the pipe thickness, and to reduce the weight of the high-strength pipe and to reduce the manufacturing cost, a new type of weight reduction type high strength non- And to provide a method for manufacturing a multi-tube for use in a pipe.

According to an aspect of the present invention for achieving the above object, the present invention provides a metal mold having a molding hole portion (11) having an inner diameter equal to an outer diameter of an outer tube (2) constituting an outer peripheral surface of a multi- The mold 10 is provided with a discharge space 14 formed in a tapered shape so as to have a diameter larger than that of the molding hole portion 11 in front of the molding hole portion 11, (12) formed in a tapered shape so as to have a larger diameter than the molding hole portion (11), and an inlet space (13) formed in the shape of a cylinder behind the molding hole introduction portion (12) (10a) and is mounted to the die holder (30);
The mandrel 20 having the molding surface portion 25a having the same outer diameter as the inner diameter of the inner tube 3 constituting the inner circumferential surface of the multi-gravity steel pipe 1 passes through the molding hole portion 11 of the mold 10 Shaped molding part (not shown) which is disposed inside the inner pipe material 3 'and has a molding surface part 25a parallel to the inner circumferential surface 11a forming the molding hole part 11 of the mold 10, 25); A tip portion 26 extending from the tip of the forming portion 25 and tapered to have a smaller diameter than the forming portion 25; The tapered angle is formed in a shape extending from the rear end of the forming part 25 to have a diameter larger than that of the forming part 25, (27) formed such that an inner circumferential surface (12a) thereof is smaller than a tapered angle; A guide portion 28 extending from the rear end of the introduction portion 27 and having a cylindrical shape larger in diameter than the molding portion 25; A floating mandrel 20b having a configuration including a rear end portion 29 extending from the rear end of the guide portion 28 and tapered so as to have a smaller diameter than the guide portion 28 is used as the mandrel 20 A mandrel placement step;
The outer tubular material 2 'and the inner tubular material 3', which are formed into the outer tube 2 and the inner tube 3 of the multi-gravity steel pipe 1, pass through the inside of the mold 10 by the drawing process (1), which are integrally joined to each other,
The outer diameter of the outer tube material 2 'is reduced to the outer diameter of the outer tube 2 of the multi-gauge steel pipe 1 in the course of passing through the molding hole portion 11 of the mold 10, The inner diameter of the inner tube material 3 'passing through the molding surface portion 25a of the mandrel 20 positioned in the molding hole portion 11 is reduced to the inner diameter of the inner tube 3 of the multi- And a plurality of tube forming steps,
A coating layer 4 made of zirconium material is formed on the inner circumferential surface of the outer tube material 2 'and the outer circumferential surface of the inner tube material 3' constituting the multi-gravity steel pipe 1, So,
A plurality of steel tubes including an outer tube 2 forming an outer peripheral surface and an inner tube 3 forming an inner peripheral surface are joined to each other through a drawing process using a mold 10 and a mandrel 20, A method for manufacturing a weight reduction type multi-pipe for forming high strength non-welded steel pipe, characterized by molding a steel pipe (1).

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According to the method of manufacturing a multi-pipe for forming a heavy-weight heavy-duty seamless steel pipe according to the present invention, it is possible to easily and easily manufacture a high strength non-pipe steel pipe without increasing the thickness of the pipe. .

1 is a block diagram illustrating a method for manufacturing a weight reduction type multi-pipe for forming high strength non-steel pipe according to an embodiment of the present invention;
FIG. 2 is a view showing a mold used in a method for manufacturing a weight reduction type high strength multimode steel pipe multi-pipe according to an embodiment of the present invention;
3 (a) and 3 (b) illustrate a drawing die and a roll die-forming die for a method of manufacturing a weight reduction type high strength multimode steel pipe multi-pipe according to an embodiment of the present invention;
4 (a) and 4 (b) illustrate a mandrel for a weight reduction type multi-tube manufacturing method for forming a high strength non-welded steel pipe according to an embodiment of the present invention;
5 (a) and 5 (b) illustrate how a multi-walled steel pipe is formed through a method for manufacturing a weight reduction type high strength seamless steel pipe according to an embodiment of the present invention;
6 (a) and 6 (b) are diagrams illustrating the formation of a multi-walled steel pipe through an outer pipe and an inner pipe having a zircon coating layer.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings 1 to 6. On the other hand, in the drawings and the detailed description, there is a description of the construction and operation that can be easily understood by those skilled in the art from a general seamless steel pipe, a drawing process, a cold rolling process, a mold, a mandrel, a fixed mandrel, The cities and references are brief or omitted. In the drawings and specification, there are shown in the drawings and will not be described in detail, and only the technical features related to the present invention are shown or described only briefly. Respectively.

The method for manufacturing a multi-pipe for forming a heavy-weight type heavy-duty non-welded steel pipe according to the present invention comprises the steps of: forming an outer pipe (2) to form an outer circumferential surface of an ungrained steel pipe (1) Are joined to each other through a drawing process or a cold rolling process using a mold (10) and a mandrel (20) to mold a multi-core steel pipe (1) having high strength. For this purpose, a method for manufacturing a multi-pipe for forming a weight reduction type high strength non-welded steel pipe according to an embodiment of the present invention is performed through a mold-including step and a multi-tube forming step as shown in FIG.

The step of providing a mold is a step of providing a mold 10 having a molding hole portion 11 having an inner diameter equal to the outer diameter of the outer tube 2 constituting the outer peripheral surface of the multi- 2, the mold 10 has a discharge space 14 formed in a tapered shape so as to have a larger diameter than the molding hole portion 11 in front of the molding hole portion 11, a molding hole portion 11, A molding hole introducing portion 12 formed in a rearward tapered shape so as to have a diameter larger than the molding hole portion 11 and an inlet space 13 formed in a cylindrical shape rearward of the molding hole introducing portion 12 Lt; / RTI > 3 (a), the step of providing a mold to be applied to the drawing process includes a drawing die 10a to be mounted on the die holder 30, and a roll die forming mold 10b as shown in FIG.

The mandrel positioning step is a step of positioning the mandrel 20 having the molding surface portion 25a having the same outer diameter as the inner diameter of the inner tube 3 forming the inner peripheral surface of the multi- Is disposed inside the inner tube material 3 'through which the hole portion 11 passes.

The mandrel 20 may be composed of a fixed mandrel 20a or a floating mandrel 20b.

The fixed mandrel 20a has a main cylindrical body 20a having an outer peripheral surface formed with a molding surface portion 25a parallel to the inner peripheral surface 11a forming the molding hole portion 11 of the mold 10 as shown in Fig. 21); A tip end portion 22 formed from a tip end of the main cylindrical body 21 and tapered so as to have a smaller diameter than the main cylindrical body 21; A rear end portion 23 extending from the rear end of the main cylindrical body 21 and tapered so as to have a smaller diameter than the main cylindrical body 21; And a connecting rod (24) extending from the rear end (23).

The floating mandrel 20b includes a cylindrical molding portion 25 having a molding surface portion 25a parallel to the inner peripheral surface 11a forming the molding hole portion 11 of the mold 10, A tip portion 26 extending from the tip of the forming portion 25 and tapered to have a smaller diameter than the forming portion 25; An introducing portion 27 formed to extend from the rear end of the forming portion 25 and tapered so as to have a larger diameter than the forming portion 25; A guide portion 28 extending from the rear end of the introduction portion 27 and having a cylindrical shape larger in diameter than the molding portion 25; And a rear end portion 29 extending from the rear end of the guide portion 28 and tapered so as to have a smaller diameter than the guide portion 28. [ The taper angle of the introduction part 27 constituting the floating mandrel 20b is formed such that the inner peripheral surface 12a of the molding hole introduction part 12 connected to the molding hole part 11 of the mold 10 is smaller than the taper angle .

The multi-tube forming step is carried out in such a manner that the outer tube material 2 'and the inner tube material 3', which are formed into the outer tube 2 and the inner tube 3 of the multi- And then joined together while passing through the inside of the mold 10 to form an integrated multi-gauge steel pipe 1. The outer diameter of the outer tube material 2 'is reduced to the outer diameter of the outer tube 2 of the multi-gauge steel pipe 1 in the process of passing through the molding hole portion 11 of the mold 10, The inner diameter of the inner tube material 3 'passing through the molding surface portion 25a of the mandrel 20 positioned in the molding hole portion 11 of the inner tube 3 of the multi- . The thickness of the outer pipe material 2 'and the inner pipe material 3' are pressed and joined between the mold 10 and the mandrel 20 to increase the material density, The strength is increased.

Meanwhile, as shown in FIG. 6, the method for manufacturing a weight reduction type high strength multi-core steel pipe according to an embodiment of the present invention includes the steps of forming an inner circumferential surface of an outer pipe material 2 ' A coating layer 4 made of a zirconium material is formed on the outer circumferential surface of the steel tube 3 ', and then the multiple tube forming step is performed, thereby increasing the bonding force between the plurality of steel tubes.

The method for manufacturing a weight reduction type high strength multimode steel pipe for forming multiple pipes according to an embodiment of the present invention having a structure as described above is characterized in that a plurality of steel pipes are connected to each other by a pull die 10a or roll die forming mold 10b The steel pipe can be manufactured by a drawing process or a cold rolling process in which a plurality of steel pipes 1 are formed while being passed through a plurality of steel pipes 1, The weight of the pipe can be reduced and the manufacturing cost can be reduced.

As described above, the method for manufacturing a weight reduction type multi-tube for forming high strength non-welded steel pipe according to an embodiment of the present invention has been described with reference to the above description and drawings, but this is merely an illustrative example, It will be understood by those skilled in the art that various changes and modifications may be made without departing from the scope of the invention.

1: Multiple steel pipe 2: External pipe
2 ': outer tube material 3: inner tube
3 ': inner tube material 4: zirconium coating layer
10: mold 10a: drawing mold
10b: roll die forming mold 11: molding hole portion
11a: Molding hole area inner circumferential surface 12: Molding hole introduction part
12a: Molding hole introduction part inner peripheral surface 13: Entrance space
14: discharge space 20: mandrel
20a: Fixed mandrel 20b: Floating mandrel
21: main cylinder 22: distal end
23: rear end portion 24: connecting rod
25: forming part 25a: forming surface part
26: distal end 27:
28: guide portion 29: rear end portion

Claims (7)

delete The mold 10 is provided with a molding hole portion 11 having an inner diameter equal to the outer diameter of the outer tube 2 constituting the outer circumferential surface of the multi- (14) formed in a tapered shape so as to have a diameter larger than that of the molding hole portion (11), a tapered shape formed so as to have a larger diameter than the molding hole portion (11) behind the molding hole portion (10) having a forming hole introducing portion (12) and an inlet space (13) formed in the shape of a cylinder behind the forming hole introducing portion (12) and being mounted to the die holder (30) ;
The mandrel 20 having the molding surface portion 25a having the same outer diameter as the inner diameter of the inner tube 3 constituting the inner circumferential surface of the multi-gravity steel pipe 1 passes through the molding hole portion 11 of the mold 10 Shaped molding part (not shown) which is disposed inside the inner pipe material 3 'and has a molding surface part 25a parallel to the inner circumferential surface 11a forming the molding hole part 11 of the mold 10, 25); A tip portion 26 extending from the tip of the forming portion 25 and tapered to have a smaller diameter than the forming portion 25; The tapered angle is formed in a shape extending from the rear end of the forming part 25 to have a diameter larger than that of the forming part 25, (27) formed such that an inner circumferential surface (12a) thereof is smaller than a tapered angle; A guide portion 28 extending from the rear end of the introduction portion 27 and having a cylindrical shape larger in diameter than the molding portion 25; A floating mandrel 20b having a configuration including a rear end portion 29 extending from the rear end of the guide portion 28 and tapered so as to have a smaller diameter than the guide portion 28 is used as the mandrel 20 A mandrel placement step;
The outer tubular material 2 'and the inner tubular material 3', which are formed into the outer tube 2 and the inner tube 3 of the multi-gravity steel pipe 1, pass through the inside of the mold 10 by the drawing process (1), which are integrally joined to each other,
The outer diameter of the outer tube material 2 'is reduced to the outer diameter of the outer tube 2 of the multi-gauge steel pipe 1 in the course of passing through the molding hole portion 11 of the mold 10, The inner diameter of the inner tube material 3 'passing through the molding surface portion 25a of the mandrel 20 positioned in the molding hole portion 11 is reduced to the inner diameter of the inner tube 3 of the multi- And a plurality of tube forming steps,
A coating layer 4 made of zirconium material is formed on the inner circumferential surface of the outer tube material 2 'and the outer circumferential surface of the inner tube material 3' constituting the multi-gravity steel pipe 1, So,
A plurality of steel tubes including an outer tube 2 forming an outer peripheral surface and an inner tube 3 forming an inner peripheral surface are joined to each other through a drawing process using a mold 10 and a mandrel 20, A method for manufacturing a weight reduction type high strength non-welded steel pipe for forming a multiple pipe, characterized by molding the steel pipe (1). delete delete delete delete delete
KR1020150110747A 2015-08-05 2015-08-05 Manufacturing method of multi-layered pipe for seamless steel pipe with low weight and high strength KR101790100B1 (en)

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KR1020150110747A KR101790100B1 (en) 2015-08-05 2015-08-05 Manufacturing method of multi-layered pipe for seamless steel pipe with low weight and high strength

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KR1020150110747A KR101790100B1 (en) 2015-08-05 2015-08-05 Manufacturing method of multi-layered pipe for seamless steel pipe with low weight and high strength

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KR101790100B1 true KR101790100B1 (en) 2017-10-25

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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003112218A (en) * 2001-09-28 2003-04-15 Usui Internatl Ind Co Ltd Method for manufacturing thick-wall thin-diameter tube
JP2005104287A (en) * 2003-09-30 2005-04-21 Miyata Ind Co Ltd Bicycle frame pipe and its processing method
KR101175461B1 (en) * 2008-02-08 2012-08-20 수미도모 메탈 인더스트리즈, 리미티드 Drawing plug of pipe material and drawing method employing the plug

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3519966B2 (en) 1999-01-07 2004-04-19 新日本製鐵株式会社 Ultra-high-strength linepipe excellent in low-temperature toughness and its manufacturing method

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003112218A (en) * 2001-09-28 2003-04-15 Usui Internatl Ind Co Ltd Method for manufacturing thick-wall thin-diameter tube
JP2005104287A (en) * 2003-09-30 2005-04-21 Miyata Ind Co Ltd Bicycle frame pipe and its processing method
KR101175461B1 (en) * 2008-02-08 2012-08-20 수미도모 메탈 인더스트리즈, 리미티드 Drawing plug of pipe material and drawing method employing the plug

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