US20110023569A1 - Method for Producing Seamless Pipe - Google Patents
Method for Producing Seamless Pipe Download PDFInfo
- Publication number
- US20110023569A1 US20110023569A1 US12/884,983 US88498310A US2011023569A1 US 20110023569 A1 US20110023569 A1 US 20110023569A1 US 88498310 A US88498310 A US 88498310A US 2011023569 A1 US2011023569 A1 US 2011023569A1
- Authority
- US
- United States
- Prior art keywords
- plug
- rolls
- pass line
- piercing
- pair
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 20
- 238000005096 rolling process Methods 0.000 claims abstract description 41
- 230000037303 wrinkles Effects 0.000 abstract description 10
- 230000003746 surface roughness Effects 0.000 description 12
- 229910000831 Steel Inorganic materials 0.000 description 9
- 239000010959 steel Substances 0.000 description 9
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000004513 sizing Methods 0.000 description 4
- 230000003247 decreasing effect Effects 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000009467 reduction Effects 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- 229910000851 Alloy steel Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 238000009499 grossing Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 239000000523 sample Substances 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 230000000593 degrading effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 238000007788 roughening Methods 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
- B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
- B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B25/00—Mandrels for metal tube rolling mills, e.g. mandrels of the types used in the methods covered by group B21B17/00; Accessories or auxiliary means therefor ; Construction of, or alloys for, mandrels or plugs
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B27/00—Rolls, roll alloys or roll fabrication; Lubricating, cooling or heating rolls while in use
- B21B27/02—Shape or construction of rolls
- B21B27/024—Rolls for bars, rods, rounds, tubes, wire or the like
- B21B27/025—Skew rolls
Definitions
- the present invention relates to a method for producing a seamless pipe.
- the Mannesmann process is known in which a seamless pipe is obtained by subjecting a heated round billet to piercing-rolling with a piercing mill, then to elongation rolling with a mandrel mill, a plug mill or the like, and further to sizing with a sizing mill to yield the seamless pipe.
- the piercing mill is usually a piercing machine having rolling rolls consisting of a pair of barrel-shaped or cone-shaped main rolls (also referred to as skew rolls), guide devices such as a guide shoe, disk rolls, a roller-type guide or the like, and an inner surface regulating tool referred to as a plug.
- rolling rolls consisting of a pair of barrel-shaped or cone-shaped main rolls (also referred to as skew rolls), guide devices such as a guide shoe, disk rolls, a roller-type guide or the like, and an inner surface regulating tool referred to as a plug.
- FIG. 1 is a schematic view illustrating an example of a skew piercing mill using cone-shaped skew rolls
- FIG. 2 is a schematic view taken in the direction of A-A in FIG. 1
- FIG. 3 is a view schematically illustrating the shape of the plug.
- a pair of main rolls 1 is disposed to face each other so as for each of the axial centerlines of the rolls to form a cross angle of ⁇ in relation to the pass line X-X of the round billet B as a workpiece.
- one of the main rolls 1 is disposed to form a feed angle ⁇ in relation to the pass line X-X.
- the other main roll 1 not shown in FIG. 2 is disposed to face the one of the main rolls 1 , with the pass line X-X interposed therebetween, at the feed angle ⁇ in relation to the pass line X-X.
- the main rolls 1 to exert spiral movement to the round billet B are directly connected to driving devices 4 respectively, so as to be rotated about the axial centerlines of the rolls as the rotational centerlines.
- a pair of disk rolls 2 is disposed to face each other, around the pass line with a phase shift of 90° from the pair of main rolls 1 .
- the pair of disk rolls 2 is rotationally driven in the same direction as the traveling direction of the workpiece at a predetermined speed, to serve an important role in making the workpiece round in shape through suppressing the increase of the circumferential length of the workpiece during wall thickness processing.
- a plug 3 has a bombshell-like shape whose base end is supported by the front end of a mandrel bar M, and the plug 3 and the mandrel bar M are disposed on the pass line X-X.
- the material for the plug 3 Cr—Ni low alloy steels are usually used, and an oxide layer is formed on the plug by heat pretreatment in order to enhance the durability.
- the plug 3 is mainly composed of a rolling section 31 , a reeling section 32 and a relief section 33 , and has the maximum diameter of Pd at the boundary between the reeling section 32 and the relief section 33 .
- the rolling section 31 mainly plays a role of piercing the solid billet
- the reeling section 32 plays a role of equalizing the wall thickness of the hollow shell and at the same time a role of smoothing the inner surface of the hollow shell.
- the reeling section 32 has a half angle ⁇ p in relation to the axial center of the plug, namely, the pass line of the round billet (see FIG. 5 ).
- the heated round billet B is fed rightward on the pass line X-X in the figure, and rolled while the round billet is being subjected to wall thickness processing with the main rolls 1 and the plug 3 during the passage of the round billet through the gap between the skew rolls.
- the round billet B spirally moves on the pass line X-X, and the axial center portion of the round billet is pierced with the plug 3 to be converted into a hollow shell.
- the asperities formed on the inner surface of the hollow shell are flattened out by the inner surface regulating tools in the lower process such as the plug of the elongator, the bar of the mandrel mill and the plug of a plug mill, and then the asperities develop into wrinkle flaws (eruption flaws).
- the occurrence of the fine inner surface flaws in final products is attributed to the properties and conditions (roughness) of the inner surface of the hollow shell after the piercing with a piercing mill.
- Patent Document 1 a method for producing a seamless steel pipe by using a plug where the scale coated layer of the reeling section is made thinner than that of the rolling section.
- Patent Document 1 JP10-249412A
- the removal amount of the scale coated layer is required to be strictly regulated, and when the control of the coated layer thickness is not performed properly to make the coated layer thickness too thin, problems such as the scoring of the reeling section and shortening of the tool life of the plug may arise.
- the present invention takes as its object the provision of a method for producing a seamless pipe, capable of improving the properties and conditions of the inner surface of a hollow shell after piercing-rolling and suppressing the wrinkle flaws of a seamless pipe.
- FIG. 4 is a schematic view illustrating an example of the piercing-rolling process in the cross section perpendicular to the pass line.
- a workpiece 5 is pressed into the space formed by the pair of main rolls 1 and the plug 3 , and thus the workpiece 5 is subjected to the wall thickness processing. Thereafter, the outer diameter increase is suppressed at a half-turned position by the disk rolls 2 , and the wall thickness processing is conducted again by the pair of main rolls 1 and the plug 3 .
- the wall thickness processing is conducted again by the pair of main rolls 1 and the plug 3 .
- the inner surface of the workpiece 5 having reached the region indicated by “a” in FIG. 4 undergoes the action of a contraction force in the circumferential direction, and thus wrinkles can occur.
- the outer surface of the workpiece is brought into contact with the main rolls 1 .
- the workpiece 5 undergoes the outer diameter processing, and hence the inner surface wrinkles formed in the region “a” are deepened.
- the inner surface of the workpiece 5 is brought into contact with the plug 3 . At this time, the wrinkles are stretched in the circumferential direction to develop into fine flaws.
- the present inventor investigated the factors degrading the properties and conditions of the inner surface of workpieces, and consequently has discovered the following findings with respect to the occurrence of the piercing troubles such as the roughening of the inner surface of a pipe and the tail clogging of the workpiece (meaning the condition in which on completion of piercing-rolling, the workpiece is not yet detached from the main rolls or the plug remains in the bottom portion of the workpiece).
- ⁇ r means the half angle (see “ ⁇ r ” in FIG. 5 ) between the pass line and the main roll face in the condition where the feed angle of the main roll is zero
- ⁇ p means the half angle (see “ ⁇ r ” in FIG. 5 ) between the pass line and the reeling section of the plug. It is to be noted that the number of times R n of the reeling of the plug is obtained from the following formula:
- L p means the length (mm) of the reeling section
- d means the value obtained from the following formula
- ⁇ means the feed angle (°) of the main rolls:
- d 1 is the outer diameter (mm) of the round billet
- d 2 is the outer diameter of the hollow shell
- the present invention has been achieved on the basis of such findings as described above, and involves a method for producing a seamless pipe shown in the following [1] to [4].
- R n The number of times of the reeling of the plug
- R n The number of times of the reeling of the plug
- R n The number of times of the reeling of the plug
- the reeling section means the part satisfying any one of the following conditions:
- G 1 The distance (mm) between the plug and the roll at the starting position in the corresponding part of the plug
- G 2 The distance (mm) between the plug and the roll at the completion position in the corresponding part of the plug
- Face angle difference (°) face angle of the concerned part of the plug-face angle of the exit side of the rolls:
- the starting position in the corresponding part of the plug means, for example, the position of the border line between the sections indicated by reference numerals 31 and 32 in FIG. 3
- the completion position in the corresponding part of the plug means, for example, the position of the border line between the sections indicated by reference numerals 32 and 33 in FIG. 3 .
- the properties and conditions of the inner surface of a hollow shell after piercing-rolling can be improved, and the wrinkle flaws in a seamless pipe which is obtained by performing elongation rolling and sizing after piercing-rolling can be prevented.
- FIG. 1 is a schematic view illustrating an example of a skew piercing mill using cone-shaped skew rolls
- FIG. 2 is a schematic view showing a view taken in the direction of A-A in FIG. 1 ;
- FIG. 3 is a view schematically illustrating the shape of a plug
- FIG. 4 is a schematic view illustrating an example of a piercing-rolling process in a cross section perpendicular to a pass line;
- FIG. 5 is a schematic view illustrating main rolls and the plug under the conditions that the feed angle ⁇ is zero;
- FIG. 6 is a graph showing the relation between ⁇ and R n ;
- FIG. 7 is a graph showing the relation between D 2 /D 1 and R n .
- a piercing mill can be used in which a plug is disposed along a pass line, between a pair of skew rolls and also between a pair of guide devices, the members in each of these pairs being disposed to face each other around the pass line, and which has usual guide devices such as guide shoes, disk rolls or roller-type guides.
- the shape of the plug is also not particularly limited.
- a plug having a structure which consists of the rolling section 31 , the reeling section 32 and the relief section 33 as shown in FIG. 3 and which has a maximum diameter at the boundary between the reeling section 32 and the relief section 33 .
- disk rolls as the guide device because the disk rolls can increase the speed of the material in the axial direction. It is also preferable to use cone-shaped rolls as the main rolls.
- the round billet to be subjected to piercing-rolling is required to be heated to 1300° C. or lower.
- the temperature of the round billet exceeds 1300° C., inner surface flaws occur due to the melting of the inner surface of the round billet to degrade the properties and conditions of the inner surface of the pipe.
- the resistance to deformation of the round billet becomes greater with the considerable decrease of the temperature to make it impossible to perform piercing-rolling or remarkably shorten the operating lives of the plug and other production facilities. Therefore, it is preferable to set the temperature of the round billet at 1150° C. or higher.
- ⁇ defined by the following formula (a) is required to be set at ⁇ 1.0 or more:
- the inner surface of the hollow shell after piercing-rolling is smoothed by increasing the number of times R n of the reeling of the plug; however, depending on the value of the plug face angle ⁇ p relative to that of the exit-side face angle ⁇ r of the main rolls, some problems may occur including the insufficient smoothness and the failures such as the tail clogging and the unevenness of the wall thickness. This tendency is enhanced with the decrease of the above-described ⁇ , and when ⁇ is less than ⁇ 1.0, even the increase of the number of times Rr, of the reeling of the plug fails in smoothing the inner surface of the hollow shell after piercing-rolling. Therefore, ⁇ is set at ⁇ 1.0 or more.
- the number of times R n of the reeling of the plug is required to satisfy the relation represented by the following formula (b) in terms of ⁇ . More preferable is the case where the following formula (b1) is satisfied:
- R n of the reeling of the plug preferably further satisfies the following formula (c). More preferable is the case where the following formula (d) is satisfied:
- the inner surface roughness of the hollow shell after piercing-rolling tends to be affected by the roll diameter at the position on the exit side of the main rolls.
- the main roll outer diameter D 2 at the maximum diameter position of the plug is set to be larger than the gorge portion diameter D 1 of the main rolls, the compressive strain in the circumferential direction acting on the inner surface of the workpiece tends to be relaxed, and consequently the suppression of the wrinkles on the inner surface of the pipe is facilitated.
- the small ⁇ value make it difficult to smooth the inner surface of the pipe, however, by setting the relation between D 2 /D 1 and R n so as to satisfy the conditions represented by the above-described formula (c), the surface roughness of the inner surface of the pipe can be improved.
- the surface roughness of the inner surface of the pipe is further improved by setting the relation between D 2 /D 1 and R n so as to satisfy the above-described formula (d).
- the method for producing a seamless pipe according to the present invention can be applied to any pipes such as metal pipes, ordinary steel pipes, low-alloy steel pipes and high-alloy steel pipes, and is particularly suitable for steel pipes with smooth inner surfaces which are used for automobile components.
- a slab produced by continuous casting from the steel having the chemical composition shown in Table 1 was subjected to blooming and finished into a round billet of 225 mm in outer diameter, and from the central portion of the round billet, a round billet of 70 mm in outer diameter was machined to prepare a sample material.
- the guide device disk rolls were used; the main roll shape and the plug shape were varied, and thus piercing-rolling was performed under the production conditions shown in Table 2 or 3; and the inner surface roughness (the maximum height Rz defined by JIS-0601) of each of the obtained hollow shells was measured.
- FIG. 6 shows the properties and conditions of the inner surface of the hollow shell produced under the conditions shown in Table 2 with respect to ⁇ and R n
- FIG. 7 shows the properties and conditions of the inner surface of the hollow shell produced under the conditions shown in Table 3 with respect to D 2 /D 1 and R n .
- ⁇ , ⁇ and ⁇ mean that the inner surface roughness of the hollow shell is such that Rz>150 ⁇ m, 100 ⁇ m ⁇ Rz ⁇ 150 ⁇ m, and Rz ⁇ 100 ⁇ m, respectively.
- x means that piercing troubles such as the tail clogging occurred.
- the inner surface roughness Rz of the hollow shell exceeded 150 ⁇ m or piercing trouble occurred.
- ⁇ was ⁇ 1.0
- the surface roughness Rz was increased.
- the production conditions were regulated in such a way that R n fell in the region equal to or larger than “ ⁇ 0.24 ⁇ +1.73,” the surface roughness Rz was able to be made smaller.
- a continuous cast material having the chemical composition shown in Table 1 was converted into round billets of 191 mm in outer diameter by blooming, then each of the round billets was subjected to piercing-rolling under the conditions shown in Table 4 and from each of the round billets, 100 seamless steel pipes of 73 mm in outer diameter and 5.51 mm in wall thickness were produced, and the properties and conditions of the inner surface of the obtained seamless steel pipes were investigated. The results thus obtained are shown in Table 5.
- the properties and conditions of the inner surface of a hollow shell after piercing-rolling can be improved, and the wrinkle flaws in a seamless pipe which is obtained by performing elongation rolling and sizing after piercing-rolling can be prevented.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Reduction Rolling/Reduction Stand/Operation Of Reduction Machine (AREA)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2008082734 | 2008-03-27 | ||
JP2008-082734 | 2008-03-27 | ||
PCT/JP2009/053652 WO2009119245A1 (ja) | 2008-03-27 | 2009-02-27 | 継目無管の製造方法 |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2009/053652 Continuation WO2009119245A1 (ja) | 2008-03-27 | 2009-02-27 | 継目無管の製造方法 |
Publications (1)
Publication Number | Publication Date |
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US20110023569A1 true US20110023569A1 (en) | 2011-02-03 |
Family
ID=41113451
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/884,983 Abandoned US20110023569A1 (en) | 2008-03-27 | 2010-09-17 | Method for Producing Seamless Pipe |
Country Status (7)
Country | Link |
---|---|
US (1) | US20110023569A1 (ja) |
EP (1) | EP2281641A4 (ja) |
JP (1) | JP4471134B2 (ja) |
CN (1) | CN101980802A (ja) |
BR (1) | BRPI0910031B1 (ja) |
MX (1) | MX2010010439A (ja) |
WO (1) | WO2009119245A1 (ja) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180169738A1 (en) * | 2015-06-10 | 2018-06-21 | Jun Zhou | Method, module, and apparatus for roll-processing external pipe thread, and external pipe thread production line |
US11273483B2 (en) * | 2016-12-13 | 2022-03-15 | Shanghai Pan-China Fastening System Co., Ltd. | Threading method, rolling head, apparatus, module and production line for pipe thread, and products thereof |
CN116393515A (zh) * | 2023-06-09 | 2023-07-07 | 太原理工大学 | 一种无缝金属复合管界面热力可控连续轧制设备及方法 |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111589869B (zh) * | 2020-01-09 | 2023-08-18 | 安徽汉正轴承科技有限公司 | 一种2219铝合金管的高强韧二辊斜轧穿孔方法 |
JP7549212B2 (ja) | 2020-04-07 | 2024-09-11 | 日本製鉄株式会社 | 継目無金属管の製造方法 |
CN115156307B (zh) * | 2022-07-29 | 2024-06-25 | 无锡华贝钢管制造有限公司 | 适用于无缝钢管的数据处理方法及系统 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
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JP3228169B2 (ja) | 1997-03-07 | 2001-11-12 | 住友金属工業株式会社 | 継目無金属管の穿孔圧延用プラグおよびこのプラグを用いた継目無金属管の製造方法 |
JP3823762B2 (ja) * | 2001-06-13 | 2006-09-20 | 住友金属工業株式会社 | 継目無金属管の製造方法 |
AU2003289244A1 (en) * | 2002-12-12 | 2004-06-30 | Sumitomo Metal Industries, Ltd. | Seamless metal tube producing method |
-
2009
- 2009-02-27 CN CN2009801107802A patent/CN101980802A/zh active Pending
- 2009-02-27 MX MX2010010439A patent/MX2010010439A/es not_active Application Discontinuation
- 2009-02-27 BR BRPI0910031-8A patent/BRPI0910031B1/pt active IP Right Grant
- 2009-02-27 EP EP09723678.0A patent/EP2281641A4/en not_active Withdrawn
- 2009-02-27 JP JP2009509805A patent/JP4471134B2/ja active Active
- 2009-02-27 WO PCT/JP2009/053652 patent/WO2009119245A1/ja active Application Filing
-
2010
- 2010-09-17 US US12/884,983 patent/US20110023569A1/en not_active Abandoned
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20180169738A1 (en) * | 2015-06-10 | 2018-06-21 | Jun Zhou | Method, module, and apparatus for roll-processing external pipe thread, and external pipe thread production line |
US10913103B2 (en) * | 2015-06-10 | 2021-02-09 | Jun Zhou | Method, module, and apparatus for roll-processing external pipe thread, and external pipe thread production line |
US11273483B2 (en) * | 2016-12-13 | 2022-03-15 | Shanghai Pan-China Fastening System Co., Ltd. | Threading method, rolling head, apparatus, module and production line for pipe thread, and products thereof |
CN116393515A (zh) * | 2023-06-09 | 2023-07-07 | 太原理工大学 | 一种无缝金属复合管界面热力可控连续轧制设备及方法 |
US11911840B1 (en) | 2023-06-09 | 2024-02-27 | Taiyuan University Of Technology | Continuous rolling device and method continuous rolling device and method with interfacial temperature-force controllability for seamless metal cladding pipe |
Also Published As
Publication number | Publication date |
---|---|
EP2281641A1 (en) | 2011-02-09 |
EP2281641A4 (en) | 2013-10-02 |
MX2010010439A (es) | 2011-03-21 |
JP4471134B2 (ja) | 2010-06-02 |
BRPI0910031A2 (pt) | 2018-09-11 |
WO2009119245A1 (ja) | 2009-10-01 |
BRPI0910031B1 (pt) | 2020-07-14 |
CN101980802A (zh) | 2011-02-23 |
JPWO2009119245A1 (ja) | 2011-07-21 |
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Owner name: SUMITOMO METAL INDUSTRIES, LTD., JAPAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:INAGE, TAKATERU;YAMAKAWA, TOMIO;SHIMODA, KAZUHIRO;SIGNING DATES FROM 20100915 TO 20101013;REEL/FRAME:025157/0951 |
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STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |