JPH07303907A - Production of electric resistance welded steel tube excellent in roundness - Google Patents
Production of electric resistance welded steel tube excellent in roundnessInfo
- Publication number
- JPH07303907A JPH07303907A JP9948294A JP9948294A JPH07303907A JP H07303907 A JPH07303907 A JP H07303907A JP 9948294 A JP9948294 A JP 9948294A JP 9948294 A JP9948294 A JP 9948294A JP H07303907 A JPH07303907 A JP H07303907A
- Authority
- JP
- Japan
- Prior art keywords
- rolls
- electric resistance
- strength
- roundness
- roll
- 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.)
- Granted
Links
Abstract
Description
【0001】[0001]
【産業上の利用分野】本発明は真円度の優れた電縫鋼管
の製造方法に関し、さらに詳しくは管体の真円度ととも
に鋼管を切断した部分の真円度の優れた電縫鋼管を製造
する方法に関するものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an electric resistance welded steel pipe having an excellent roundness, and more particularly to an electric resistance welded steel pipe having an excellent roundness of a tubular body and a roundness of a cut portion of the steel pipe. The present invention relates to a manufacturing method.
【0002】[0002]
【従来の技術】従来の電縫鋼管は孔型を有するロ−ルで
帯鋼を連続的に円筒状に成形して電縫溶接を行い、その
後定形のために複数配置した絞りスタンドにて真円に近
い形状の成形を行っている。たとえば、特開昭64−2
709号公報に見られるように、従来は2個のロ−ルで
絞りをかけて、孔型で真円に近い成形を行う方法をとっ
ており、上下1組の2ロ−ルスタンドの前段には、該ス
タンドとはロ−ル軸角度が90゜異なる水平サイドロ−
ルを配して、数段の絞り成形を行うのが一般である。2. Description of the Related Art A conventional electric resistance welded steel pipe is formed by continuously forming a strip steel into a cylindrical shape by a roll having a hole shape, performing electric resistance welding, and then using a plurality of drawing stands arranged for a fixed shape. We are molding a shape close to a circle. For example, Japanese Patent Laid-Open No. 64-2
As disclosed in Japanese Patent Publication No. 709, the conventional method is to draw with two rolls to form a hole-shaped molding close to a perfect circle, and the front stage of a pair of upper and lower two roll stands. Has a horizontal side roll whose roll axis angle is 90 ° different from that of the stand.
It is common to arrange the reels and perform several stages of draw forming.
【0003】このような従来の成形法では、最終絞り成
形前のサイドロ−ルの位置設定により鋼管にかかる歪履
歴を制御して、管端の真円度をほぼ管体に近い真円度に
入る成形を行う必要がある。In the conventional forming method as described above, the strain history applied to the steel pipe is controlled by setting the position of the side roll before the final draw forming, so that the roundness of the pipe end is made to be close to that of the pipe body. It is necessary to carry out molding.
【0004】ところが、薄肉、高強度の鋼管、例えば自
動車のプロペラシャフト用鋼管のようにt/D(t:肉
厚、D:外径)が3%以下のパイプでは、管体の真円度
は良好であっても切断部が楕円形を示し真円度が劣化す
る場合があり、これは上記の2ロ−ルスタンドでは防止
が困難である。However, in the case of a thin-walled, high-strength steel pipe, for example, a pipe having a t / D (t: wall thickness, D: outer diameter) of 3% or less, such as a steel pipe for a propeller shaft of an automobile, the roundness of the tubular body is small. However, even if it is good, the cut portion may show an elliptical shape and the roundness may deteriorate, which is difficult to prevent with the above-mentioned two roll stand.
【0005】従来の成形法における2ロ−ルスタンドで
は最終絞り成形前のサイドロ−ルの位置設定により鋼管
にかかる歪履歴を制御して、管端の真円度をほぼ管体に
近い真円度に入るように成形を行なう必要がある。しか
しながら、この方法ではシーム部と母材の差などの材料
強度やt/Dにあわせて、前段のサイドロ−ル設定や孔
型を変えるなど諸条件変更の必要があり、安定操業は困
難である。In the conventional two-roll stand in the conventional forming method, the strain history applied to the steel pipe is controlled by setting the position of the side roll before the final draw forming, so that the roundness of the pipe end is a perfect circle close to that of the pipe body. It is necessary to carry out molding so that it can be repeated. However, with this method, it is necessary to change various conditions such as changing the side roll setting and the hole type in the previous stage according to the material strength such as the difference between the seam and the base material and t / D, and stable operation is difficult. .
【0006】また、特開平5−285508号公報では
材料が均質な場合には0.05〜0.5%の絞り率で4
ロ−ル分割することで定形を行なうことにより管端の変
形防止できるとしているが、シーム部と母材強度に差が
ある場合には強度差の影響による管端変形が発生し、完
全に管端変形は除去できない。Further, in Japanese Unexamined Patent Publication No. 5-285508, when the material is homogeneous, a draw ratio of 0.05 to 0.5% is used.
It is said that the pipe end can be prevented from being deformed by performing the fixed shape by dividing the roll.However, if there is a difference in the strength between the seam and the base metal, the pipe end will be deformed due to the influence of the difference in strength and the pipe will be completely deformed. Edge deformation cannot be removed.
【0007】[0007]
【発明が解決しようとする課題】本発明は、従来の方法
では困難であった、管端および管体ともに高真円度を確
保した薄肉電縫鋼管を容易に製造する方法を提供するこ
とを目的とするものである。SUMMARY OF THE INVENTION The present invention provides a method for easily manufacturing a thin electric resistance welded steel pipe having a high roundness at both the pipe end and the pipe body, which has been difficult to achieve by the conventional methods. It is intended.
【0008】[0008]
【課題を解決するための手段】本発明者らは上記の難点
を解決せんとして、サイザーの成形を詳細に解析した結
果、t/Dの小さい鋼管で鋼管の管端の真円度を高くす
ることができない原因は、2ロ−ルを用いて溶接後の鋼
管を絞り定形する成形において、管軸方向の曲げ・曲げ
戻し変形と周方向圧縮の変形が、パイプ円周方向で異な
るためであることを見いだした。DISCLOSURE OF THE INVENTION The inventors of the present invention have made a detailed analysis of the molding of the sizer to solve the above-mentioned problems, and as a result, increase the roundness of the pipe end of the steel pipe with a steel pipe having a small t / D. The reason why it is not possible is that, in the forming in which the steel pipe after welding is drawn and shaped using two rolls, the bending / bending back deformation in the pipe axial direction and the deformation due to the circumferential compression are different in the pipe circumferential direction. I found a thing.
【0009】しかも、その原因はロ−ル分割数が2ロ−
ルと少ないことに加え、さらに、パイプの材料強度が円
周方向で異なる場合には管端の真円度劣化が一段と顕著
であり、電縫鋼管においては、電縫溶接部の強度が他の
部分に比べ局部的に高く、あるいは低いことによって、
塑性変形しにくい場合やしやすい場合に管端の変形が著
しくなることを見い出した。Moreover, the cause is that the number of roll divisions is 2 rolls.
In addition, in the case where the material strength of the pipes differs in the circumferential direction, the deterioration of the roundness of the pipe end is more remarkable. By locally higher or lower than the part,
It was found that when the plastic deformation is difficult or easy, the pipe end deformation becomes remarkable.
【0010】これに対して本発明者らは上記の課題を解
決せんとして種々の方法を検討した結果、サイザー工程
において少なくとも最終段のスタンドのロ−ルをパイプ
の円周方向に4分割とすれば、管体および管端の真円度
を向上させることが可能であり、かつ電縫部の強度と母
材部の強度との比に応じて上下と左右のロ−ル底径比を
変えると管体および管端の真円度がさらに一段とよくな
ることを見出し、本発明を完成した。On the other hand, as a result of studying various methods to solve the above problems, the present inventors found that at least the roll of the stand at the final stage was divided into four in the circumferential direction of the pipe in the sizer process. For example, it is possible to improve the roundness of the pipe body and the pipe end, and to change the roll bottom diameter ratio of the upper and lower sides and the left and right sides according to the ratio of the strength of the electric resistance portion and the strength of the base material portion. The present invention has been completed by finding that the roundness of the tube body and the tube end is further improved.
【0011】すなわち、本発明の要旨とするところは、
帯鋼を連続的にロ−ル成形を行い電縫鋼管を製造する方
法において、寸法および形状を整えるサイザー工程にお
いて少なくとも最終段のスタンド部のロールをパイプ円
周方向に4分割とし、電縫部の強度と母材部の強度比に
応じて上下と左右のロ−ルの底径の比を変えて絞り成形
することを特徴とする真円度の優れた電縫鋼管の製造方
法にある。That is, the gist of the present invention is that
In a method of continuously rolling a strip steel to produce an electric resistance welded steel pipe, at least a roll of a stand portion at the final stage is divided into four in the circumferential direction of the pipe in a sizer process for adjusting the size and shape of the electric resistance welded pipe. A method for producing an electric resistance welded steel pipe having an excellent roundness, which is characterized in that the ratio of the bottom diameters of the upper and lower rolls and the left and right rolls is changed according to the strength ratio of the strength and the strength of the base material to perform draw forming.
【0012】以下、本発明の実施態様を例として、本発
明を詳細に説明する。サイザー成形の最終段に図1の如
く、鋼管1の周方向の絞りが均一になるようロ−ルを4
個(上下ロ−ル5a,5b及びサイドロール5c,5
d)とし、電縫部と母材の強度にあわせて上下ロ−ル
(5a,5b)とサイドロ−ル(5c,5d)の底径比
( Dtb/Ds )を変えることより、成形後の管端の変形
を防止することが可能になる。Hereinafter, the present invention will be described in detail with reference to embodiments of the present invention. At the final stage of the sizer molding, as shown in Fig. 1, roll the steel pipe 1 so that the circumferential drawing is uniform.
Individual (upper and lower rolls 5a, 5b and side rolls 5c, 5
d) and the bottom diameter ratio of the upper and lower rolls (5a, 5b) and side rolls (5c, 5d) according to the strength of the electric resistance welded part and the base metal.
By changing (D tb / D s ), it becomes possible to prevent deformation of the tube end after molding.
【0013】図2の如く電縫部の強度が高い場合に、等
径ロ−ルにより絞り成形を行うと、管端変形は電縫部部
分を通る軸を長軸とする楕円を示す。このとき、上下ロ
−ル(5a,5b)の底径Dtbをサイドロ−ル(5c,
5d)の底径Ds よりも小さくすることにより、この楕
円変形を相殺することが可能となるため、管端変形の防
止が可能になる。When the strength of the electric resistance welded portion is high as shown in FIG. 2, the pipe end deformation shows an ellipse whose major axis is the axis passing through the electric resistance welded portion when the draw forming is performed by the equal diameter roll. At this time, the bottom diameter D tb of the upper and lower rolls (5a, 5b) is set to the side roll (5c,
By making it smaller than the bottom diameter D s of 5d), it becomes possible to cancel this elliptical deformation, and therefore it becomes possible to prevent the pipe end deformation.
【0014】図2には母材強度が500MPa で、電縫部
の強度が母材強度よりも100MPa高い場合のロ−ル異
径化の効果を示すが、上下ロ−ルのロ−ル径Dtbに対
し、サイドロ−ルの底径Ds を、例えば0.65倍(D
tb/Ds =0.65)とすることで、変形がなく全長に
わたり高真円度な鋼管の製造が可能となることがわか
る。FIG. 2 shows the effect of changing the diameter of the roll when the strength of the base metal is 500 MPa and the strength of the electric resistance portion is 100 MPa higher than the strength of the base metal, but the roll diameter D of the upper and lower rolls is shown. For tb , the bottom diameter D s of the side roll is, for example, 0.65 times (D
tb / D s = 0.65) With, it can be seen that the deformation is the production of high roundness steel pipe over the entire length without becomes possible.
【0015】逆に電縫部の強度が母材部よりも低い場合
には、DtbをDs よりも大きくすればよい。さらに、電
縫部の強度が母材部よりも高い場合には、高くなるに従
ってDtb/Ds 比を小さくすることが好ましい。On the contrary, when the strength of the electric resistance portion is lower than that of the base material portion, D tb may be made larger than D s . Further, when the strength of the electric resistance welded portion is higher than that of the base material portion, it is preferable to decrease the D tb / D s ratio as the strength increases.
【0016】本発明のサイザーロ−ルは、シーム部分を
成形するロ−ル径のみの変更だけでなく、上下、左右は
対として対称とし、ロ−ル径を同径とするのはパイプの
非対称変形による曲がりなどの発生を防止するためであ
る。In the sizer roll of the present invention, not only the diameter of the roll for forming the seam portion is changed, but also the upper and lower sides and the left and right sides are made symmetrical as a pair. This is to prevent bending and the like due to deformation.
【0017】図3に具体的な造管の成形装置の構成例を
示す。図において、1は鋼管、2は溶接用スクイズロ−
ル、3は垂直(サイド)ロ−ル、4は水平ロ−ルであ
る。水平、垂直の組み合わせによるサイザースタンドが
複数段配置されたのち、異径4ロ−ルサイザーロ−ル5
を設置し最終定形工程とする。FIG. 3 shows an example of the construction of a concrete pipe forming apparatus. In the figure, 1 is a steel pipe, 2 is a squeeze roll for welding.
3 is a vertical (side) roll and 4 is a horizontal roll. After arranging a plurality of horizontal and vertical sizer stands, different diameter 4 rolls sizer roll 5
Is set as the final standard process.
【0018】[0018]
【実施例】本発明の実施例として、外径D=75.0
(mm)で肉厚t=1.6mm(t/D=2.1%)の薄肉
電縫鋼管を製造するのに際して、母材部の強度が500
MPa、電縫部の強度が600MPa の場合において、サイ
ザーの最終段を本発明法と従来の2ロ−ル法、等径の4
ロ−ル法を比較した。最終段の絞り量を0.2%とした
ときの管端部分の真円度測定結果を図4に示す。図4
は、従来の2ロ−ル法、等径4ロ−ル(Dtb/Ds =
1.0)、本発明による異径4ロ−ル(Dtb/Ds =
0.65)のパイプの管端形状を示す。EXAMPLE As an example of the present invention, the outer diameter D = 75.0
When manufacturing a thin electric resistance welded steel pipe with a wall thickness of t = 1.6 mm (t / D = 2.1%) in (mm), the strength of the base material is 500
In the case of MPa and the strength of the electric resistance welded portion is 600 MPa, the final stage of the sizer is the method of the present invention and the conventional two-roll method.
The roll methods were compared. FIG. 4 shows the roundness measurement results of the pipe end portion when the final stage drawing amount was 0.2%. Figure 4
Is the conventional 2-roll method, isometric 4-roll (D tb / D s =
1.0), different diameter 4 rolls according to the present invention (D tb / D s =
The pipe end shape of the pipe of 0.65) is shown.
【0019】本発明方法では溶接部分の高強度の影響を
相殺し、ほぼ管体とおなじ真円度で管端変形が発生して
いないことは明らかである。これに対して、2ロ−ル法
では水平方向の変形が著しく、等径4ロ−ル法では電縫
部を通る軸を長軸とする楕円になっており、いずれも管
端の真円度は著しく劣っていることが分かる。In the method of the present invention, the influence of the high strength of the welded portion is canceled out, and it is clear that the pipe end deformation does not occur with almost the same roundness as the pipe body. On the other hand, in the 2-roll method, the horizontal deformation is remarkable, and in the equal-diameter 4-roll method, an ellipse whose major axis is the axis passing through the electric resistance welded portion is used. Turns out to be significantly inferior.
【0020】さらに、本発明は既存のサイザーの最終段
に組み込むか、最終段のサイザーを変更することのいず
れでもよく、どちらでも管端変形を改善した薄肉電縫鋼
管を製造できる。また、ロ−ルは無駆動でも或いは駆動
方式としてもいずれでも良く、コストや前段までの装置
形式に応じていずれかを選択すればよい。Further, the present invention may be incorporated into the final stage of an existing sizer or the sizer of the final stage may be changed, and both of them can produce a thin electric resistance welded steel pipe with improved pipe end deformation. Further, the roll may be non-driving or may be a driving system, and either one may be selected according to the cost and the apparatus type up to the preceding stage.
【0021】[0021]
【発明の効果】本発明方法は、薄肉電縫鋼管において、
全長にわたり高真円度を示す鋼管を容易に製造すること
を可能にしたものであり、工業上有益な効果をもたらし
得るものである。The method of the present invention is applicable to thin-wall ERW steel pipes,
It is possible to easily manufacture a steel pipe having a high roundness over the entire length, and it is possible to bring industrially beneficial effects.
【図1】本発明において用いるロ−ル構成図。FIG. 1 is a block diagram of a roll used in the present invention.
【図2】本発明のサイザーロ−ル径比と管端の真円度の
関係を示す図。FIG. 2 is a diagram showing a relationship between a sizer roll diameter ratio of the present invention and roundness of a pipe end.
【図3】造管の成形装置の構成図。FIG. 3 is a configuration diagram of a pipe forming apparatus.
【図4】従来2ロ−ルと本発明の4ロ−ルで成形した場
合の鋼管の真円度形状の比較図。FIG. 4 is a comparison diagram of roundness shapes of steel pipes formed by the conventional 2 rolls and the 4 rolls of the present invention.
1 鋼管 2 溶接用SQロ−ル 3 垂直(サイドロ−ル) 4 水平(上下ロ−ル) 5 本発明の4ロ−ル 5a 上ロ−ル 5b 下ロ−ル 5c,5d サイドロ−ル 1 Steel Pipe 2 SQ Roll for Welding 3 Vertical (Side Roll) 4 Horizontal (Upper and Lower Roll) 5 4 Roll of the Present Invention 5a Upper Roll 5b Lower Roll 5c, 5d Side Roll
Claims (1)
を製造する方法において、寸法および形状を整えるサイ
ザー工程において少なくとも最終段のスタンドのロール
をパイプ円周方向に4分割として、電縫部の強度と母材
部の強度との比に応じて上下と左右のロ−ルの底径の比
を変えて、絞り成形することを特徴とする真円度の優れ
た電縫鋼管の製造方法。1. A method for producing an electric resistance welded steel pipe by continuously rolling a strip steel, wherein at least a roll of a stand at a final stage is divided into four in a pipe circumferential direction in a sizer process for adjusting a size and a shape. , ERW steel pipe with excellent roundness, characterized in that the ratio of the bottom diameters of the upper and lower rolls and the left and right rolls is changed according to the ratio of the strength of the electric resistance welded portion to the strength of the base metal portion, and draw forming is performed. Manufacturing method.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6099482A JP2994202B2 (en) | 1994-05-13 | 1994-05-13 | Manufacturing method of ERW steel pipe with excellent roundness |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP6099482A JP2994202B2 (en) | 1994-05-13 | 1994-05-13 | Manufacturing method of ERW steel pipe with excellent roundness |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH07303907A true JPH07303907A (en) | 1995-11-21 |
JP2994202B2 JP2994202B2 (en) | 1999-12-27 |
Family
ID=14248534
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6099482A Expired - Lifetime JP2994202B2 (en) | 1994-05-13 | 1994-05-13 | Manufacturing method of ERW steel pipe with excellent roundness |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2994202B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007007688A (en) * | 2005-06-30 | 2007-01-18 | Jfe Steel Kk | Method for preventing bend of steel tube |
CN102489915A (en) * | 2011-11-25 | 2012-06-13 | 长春轨道客车股份有限公司 | Manufacturing method of anti-deformation arc-shaped positioning copper strips for stainless steel car roof skeleton |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
KR101220867B1 (en) | 2011-07-22 | 2013-01-11 | 주식회사 포스코 | Hybrid severe plastic deformation machine |
-
1994
- 1994-05-13 JP JP6099482A patent/JP2994202B2/en not_active Expired - Lifetime
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2007007688A (en) * | 2005-06-30 | 2007-01-18 | Jfe Steel Kk | Method for preventing bend of steel tube |
CN102489915A (en) * | 2011-11-25 | 2012-06-13 | 长春轨道客车股份有限公司 | Manufacturing method of anti-deformation arc-shaped positioning copper strips for stainless steel car roof skeleton |
Also Published As
Publication number | Publication date |
---|---|
JP2994202B2 (en) | 1999-12-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
JP3498312B2 (en) | Cold reduction roll forming method for metal tube and metal tube formed thereby | |
JPH07303907A (en) | Production of electric resistance welded steel tube excellent in roundness | |
US4590781A (en) | Method for forming an electric resistance welded steel pipe | |
JPH11104710A (en) | Making of seamless square steel pipe | |
JP3119821B2 (en) | Roll forming method and breakdown roll group in ERW steel pipe manufacturing | |
JP2543283B2 (en) | Manufacturing method of ERW steel pipe with excellent roundness | |
JPS6150688B2 (en) | ||
JPH1071423A (en) | Square steel tube and its production | |
JPS63286220A (en) | Production of electric resistance welded tube | |
JPS5927654B2 (en) | Roll forming method in ERW pipe manufacturing | |
EP0133245B1 (en) | A method for forming an electric resistance welded steel pipe | |
JPH11104711A (en) | Production method for seamless square shaped steel pipe | |
JPH10258312A (en) | Manufacture of welded tube excellent in roundness | |
SU1197756A1 (en) | Method of producing rectangular tubes | |
JP2000140947A (en) | Tube forming method by bending roll and the tube | |
JPH0312975B2 (en) | ||
JP2669841B2 (en) | Welded tube forming method | |
JPH02104419A (en) | Manufacture of welded pipe | |
JPH05237540A (en) | Method for preventing tube end deformation of electric resistance welded tube | |
JP3328392B2 (en) | Welded pipe forming method | |
JP3328524B2 (en) | Open pipe manufacturing method | |
JPH0551373B2 (en) | ||
SU1704879A1 (en) | Method of producing helical-seam tubes from rolled steel strip | |
JPH05305309A (en) | Manufacture of steel tube for rack bar | |
JPH10258303A (en) | Manufacture of square seamless steel tube |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19991005 |