JPH11104710A - Making of seamless square steel pipe - Google Patents

Making of seamless square steel pipe

Info

Publication number
JPH11104710A
JPH11104710A JP27118297A JP27118297A JPH11104710A JP H11104710 A JPH11104710 A JP H11104710A JP 27118297 A JP27118297 A JP 27118297A JP 27118297 A JP27118297 A JP 27118297A JP H11104710 A JPH11104710 A JP H11104710A
Authority
JP
Japan
Prior art keywords
stand
tube
steel pipe
square
elliptical
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.)
Pending
Application number
JP27118297A
Other languages
Japanese (ja)
Inventor
Yoshitomi Onoda
義富 小野田
Takuya Nagahama
拓也 長濱
Takaaki Toyooka
高明 豊岡
Hideo Sato
秀雄 佐藤
Nobuhiko Morioka
信彦 森岡
Masaharu Kita
政春 喜多
Kenichi Yamamoto
健一 山本
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Steel Corp
Original Assignee
Kawasaki Steel Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kawasaki Steel Corp filed Critical Kawasaki Steel Corp
Priority to JP27118297A priority Critical patent/JPH11104710A/en
Publication of JPH11104710A publication Critical patent/JPH11104710A/en
Pending legal-status Critical Current

Links

Abstract

PROBLEM TO BE SOLVED: To obtain a product, corner roundness of which is small and side is flat, by hot-rolling an angle pipe with an angle molding stand, after a cross section of a cylindrical element tube is molded into an oval shape of specific ellipticity by a fixed form stand of a fixed form rolling mill located in the upstream of the first angle molding stand. SOLUTION: An oval caliber 4 is arranged on the roll 3 of a stand #5, by which the cross section of the cylindrical element tube passing through the stand #1-4 is molded to be an oval. Then, the roll 3 having the caliber 4 of square shape is used to mold the oval element tube, whose circumference length is almost determined, into square shape in succession at a stand #6-8. The corner radius of curvature of the caliber 4 of the stand #6 and #7 is made small in order to prevent the concave at the edge in forming. Ellipticity D defined in the equation of the oval element tube is made to be 1.0-30.0%. In the equation, (a) stands for the major axis length (mm) and (b) stands for the minor axis length (mm).

Description

【発明の詳細な説明】DETAILED DESCRIPTION OF THE INVENTION

【0001】[0001]

【発明の属する技術分野】本発明は、断面が角形の継目
無鋼管の製造方法に関し、特に、1スタンドが2ロール
で複数列のスタンドからなる定形圧延機(サイザー・ミ
ル)を使用し、熱間圧延で該継目無角形鋼管を製造する
技術である。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a seamless steel pipe having a rectangular cross section, and more particularly, to a method for manufacturing a seamless steel pipe using a fixed rolling mill (sizer mill) in which one stand comprises two rolls and a plurality of rows of stands. This is a technique for producing the seamless rectangular steel pipe by cold rolling.

【0002】[0002]

【従来の技術】近年、一般構造用、建材用、あるいは機
器部材として、角形鋼管が多用されるようになった。こ
れら周知の角形鋼管は、サイズ、肉厚等によって、いく
つかの製造方法が知られている。例えば、複雑な断面形
状をした角形鋼管は、熱間押出し成形法で製造され、通
常の角形鋼管は、鋼板を曲げ加工し、突き合わせ部を溶
接で接合して製造されていた。この溶接による方法は、
特開昭63−220922号公報で開示されているよう
に、まず、鋼板を円形に成形して継目部を溶接して円形
素管(所謂電縫管)を作り、これを複数スタンドからな
る角形鋼管用サイザー・ミルを通すことによって徐々に
角形断面に加工するものである。しかし、これらの方法
は、通常冷間加工によるため、製造される角鋼管の肉厚
やサイズ等に限界があり、また加工後の加工歪みを除去
する工程を必要としていた。
2. Description of the Related Art In recent years, rectangular steel pipes have been frequently used for general structures, building materials, and equipment members. Several manufacturing methods are known for these well-known square steel pipes depending on the size, wall thickness, and the like. For example, a rectangular steel pipe having a complicated cross-sectional shape is manufactured by a hot extrusion molding method, and a normal square steel pipe is manufactured by bending a steel plate and joining a butt portion by welding. This welding method is
As disclosed in JP-A-63-220922, first, a steel plate is formed into a circular shape, and a seam is welded to form a circular raw tube (so-called electric resistance welded tube). It is processed gradually into a square cross section by passing through a steel pipe sizer mill. However, since these methods are usually performed by cold working, there are limitations on the thickness, size, and the like of the square steel pipe to be manufactured, and a step of removing working distortion after working is required.

【0003】そこで、最近は、多サイズ、特に厚肉の角
形鋼管を量産できるよう、継目無鋼管の製造設備(図6
参照)の利用に着眼し、鋼鋳片(以下、ビレットとい
う)を用い直接角形にする試みが種々なされている。例
えば、特開平4−41006号公報は、「ビレットを穿
孔後、圧延加工によって円形断面の素管1を得、次いで
再加熱後多数のスタンド列より構成されるサイザー・ミ
ル2により所要断面に縮管し、次いで、前記サイザー・
ミル2の後段の少なくとも一つ以上のスタンドに配置し
た、複数のロール3より形成されパス断面を角形とした
サイザー・ミルで熱間加工することを特徴とする継目無
角形鋼管の製造方法を開示している。
In recent years, a facility for manufacturing seamless steel pipes (FIG. 6) has been developed so that large-sized, especially thick-walled rectangular steel pipes can be mass-produced.
Various attempts have been made to focus on the use of steel slabs (hereinafter referred to as billets) and focus on the use of steel slabs. For example, Japanese Unexamined Patent Publication No. Hei 4-41006 discloses that "after piercing a billet, a raw tube 1 having a circular cross-section is obtained by rolling, and then, after reheating, reduced to a required cross-section by a sizer mill 2 composed of a number of rows of stands. And then the sizer
Disclosed is a method for manufacturing a seamless rectangular steel pipe characterized by hot working with a sizer mill formed of a plurality of rolls 3 and having a rectangular path cross section, which is arranged on at least one or more stands at the subsequent stage of the mill 2. doing.

【0004】ところで、角型鋼管を柱のような建築構造
物に使用するには、日本工業規格(JIS G 346
6)を満足させる必要がある。その一つに、図5に示す
鋼管断面の角部の寸法(S値、下記(2)式で定義され
る)が肉厚tの3倍以下(S≦3.0t),及び角鋼管
断面の辺の平坦度Pが辺長Lの0.5%以下(P/L≦
0.005)という規定がある。つまり、角の丸みがで
きるだけ少なく、辺が平坦であることである。なお、実
用上は、該角部の寸法(S値)は、もっと厳しく1.5
t以下が望まれている。
By the way, in order to use a square steel pipe for a building structure such as a pillar, Japanese Industrial Standard (JIS G 346) has been adopted.
It is necessary to satisfy 6). One of them is that the dimension (S value, defined by the following equation (2)) of the corner of the steel pipe section shown in FIG. 5 is three times or less (S ≦ 3.0 t) of the wall thickness t, and Is 0.5% or less of the side length L (P / L ≦
0.005). That is, the corners are as small as possible and the sides are flat. In practice, the size (S value) of the corner is more strictly 1.5 times.
t or less is desired.

【0005】 S=(1/2)×(L−LF ) ・・・・・(2)式 ここで、L: 角鋼管断面の辺長(mm) LF :角鋼管断面の辺のフラット部長さ(mm) t: 角鋼管の肉厚(mm) かかる要望を現在国内で主流となっている冷間圧延で達
成しようとすると、角部の曲率半径R(ほぼS値と同じ
意味を持つ)が大、つまり丸みが大きくなる。特に、t
/L≧0.05の厚肉鋼管では、R/t>3になり、そ
の結果として、図5に示す辺のフラット部の長さLF
短くなる。そこで、熱間圧延で加工し易くして製造すれ
ば、この問題は解消すると考えられた。事実、加工度を
高め、鋼管断面の圧延による減面率(後述するが、1−
0 /Ai で表わされる)を大きくすれば、前記Rは小
さくなり、辺のフラット部の長さが長くなると共に、S
値も小さくなった。なお、この減面率は、図5に示すよ
うに、断面の実肉部での値であり、空間部は含まない。
S = (1 /) × (L−L F ) Equation (2) where L: side length (mm) of the cross section of the square steel pipe L F : flat of the side of the cross section of the square steel pipe Section length (mm) t: Wall thickness of square steel pipe (mm) If this demand is to be achieved by cold rolling, which is currently the mainstream in Japan, the radius of curvature R of the corner (which has almost the same meaning as the S value) ) Is large, that is, the roundness is large. In particular, t
The thick steel pipe /L≧0.05, becomes R / t> 3, as a result, also shortened the length L F of the flat portion of the side shown in FIG. Therefore, it was considered that this problem would be solved by manufacturing by making it easy to work by hot rolling. In fact, the degree of work was increased, and the area reduction rate due to the rolling of the steel pipe section (described later, 1-
When A 0 / A i is increased, R becomes smaller, the length of the flat portion of the side becomes longer, and S
The value has also decreased. Note that, as shown in FIG. 5, the area reduction rate is a value at a solid portion of the cross section and does not include a space portion.

【0006】しかしながら、このように減面率を大きく
すると、圧延中の鋼管に座屈が生じ、前記した角鋼管断
面の辺の平坦度が悪くなるという別の問題が生じた。前
記特開平4−41006号公報には、1スタンドに3つ
のロールを使用したサイザー・ミル(定形圧延機)で熱
間圧延する記載があるが、具体的に実施する条件の記載
がないので、該公報からかかる問題の解決に関する情報
は一切得られなかった。
However, when the area reduction rate is increased as described above, buckling occurs in the steel pipe during rolling, and another problem that the flatness of the side of the cross section of the square steel pipe deteriorates occurs. Japanese Patent Application Laid-Open No. 4-41006 describes that hot rolling is performed by a sizer mill (standard-size rolling mill) using three rolls for one stand. No information on solving such a problem was obtained from the publication.

【0007】そこで、本出願人は、最近、1スタンドに
2ロールを使用したサイザー・ミル(定形圧延機)を用
いて円筒状素管を角筒に成形し、継目無角形鋼管を製造
することを試み、比較的良好な結果を得ている。しかし
ながら、前記円筒状素管1をサイザー・ミル2のうち角
成形スタンドに通管させると、図3(a)に示すよう
に、ロール3に設けた角形カリバー12の底側では、被
成形体の肉がカリバー形状にほぼ一致するが、ロール3
の間隙では、前記被成形体の一部の肉がカリバーよりは
み出し、角が必要以上に鋭くなることが多い。これで
は、図3(b)のように、角鋼管11の断面が不均一に
なり、前記したユーザの要望を満足できないことが明ら
かである。
Therefore, the present applicant has recently produced a seamless tubular steel tube by forming a cylindrical tube into a rectangular tube using a sizer mill (standard-size rolling mill) using two rolls per stand. And obtained relatively good results. However, when the cylindrical raw tube 1 is passed through a square forming stand of the sizer mill 2, as shown in FIG. Meat almost matches the caliber shape, but roll 3
In the gap, a part of the body of the molded body protrudes from the caliber, and the corner is often sharpened more than necessary. In this case, as shown in FIG. 3 (b), the cross section of the square steel pipe 11 becomes non-uniform, and it is apparent that the above-mentioned demand of the user cannot be satisfied.

【0008】[0008]

【発明が解決しようとする課題】本発明は、かかる事情
を鑑み、1スタンドに2ロールを使用しても、角部の丸
みが少なく、且つ辺の平坦な製品が得られる継目無角形
鋼管の製造方法を提供することを目的としている。
SUMMARY OF THE INVENTION In view of such circumstances, the present invention is directed to a seamless rectangular steel pipe having a rounded corner and a product having a flat side even if two rolls are used for one stand. It is intended to provide a manufacturing method.

【0009】[0009]

【課題を解決するための手段】発明者は、上記目的を達
成するため、継目無鋼管製造設備のサイザー・ミルに1
スタンドが2ロールの角成形スタンドを用い、角形鋼管
の角部の丸み低減と辺の平坦化を達成する圧延条件を見
い出すことに鋭意努力した。その結果、角成形スタンド
に送入する素管の形状変更で上記目的が達成できること
を知り、本発明を完成させた。
In order to achieve the above object, the inventor of the present invention has proposed a method for installing a steel pipe in a seamless steel pipe manufacturing facility.
Using a two-roll square forming stand, we worked diligently to find out the rolling conditions for reducing the roundness of the corners of the rectangular steel pipe and flattening the sides. As a result, the present inventors have found that the above object can be achieved by changing the shape of the raw tube fed into the square forming stand, and completed the present invention.

【0010】すなわち、本発明は、継目無鋼管製造設備
でビレットに穿孔して得た円筒状素管を、1スタンドが
2ロールからなる定形圧延機で熱間圧延して角筒に成形
するに際し、前記定形圧延機のうち最初の角成形スタン
ドより上流側の定形スタンドで、前記円筒状素管の断面
を楕円状に成形してから、該楕円状素管を角成形スタン
ドに通管して角筒に熱間圧延することを特徴とする継目
無角形鋼管の製造方法である。
That is, the present invention relates to a method for hot rolling a cylindrical raw tube obtained by perforating a billet in a seamless steel pipe manufacturing facility with a fixed rolling mill in which one stand comprises two rolls to form a square tube. In a fixed stand on the upstream side of the first square forming stand of the fixed mill, the cross section of the cylindrical base tube is formed into an elliptical shape, and then the elliptical base tube is passed through the square forming stand. A method for producing a seamless rectangular steel pipe, comprising hot rolling into a rectangular tube.

【0011】また、本発明は、前記楕円状素管の断面の
長辺を、角成形ロールに設けたカリバー底側に向けて、
該楕円状素管を熱間圧延することを特徴とする継目無角
形鋼管の製造方法である。さらに、本発明は、前記楕円
状素管の下記(1)式で定義する楕円率(D)を、1.
0〜30.0%とすることを特徴とする請求項1又は2
記載の継目無角形鋼管の製造方法でもある。
[0011] Further, the present invention provides a method according to the present invention, wherein a long side of the cross section of the elliptical base tube is directed toward a caliber bottom provided on a square forming roll.
A method for producing a seamless rectangular steel pipe, comprising hot rolling the elliptical raw pipe. Further, the present invention provides an ellipticity (D) defined by the following equation (1) of the elliptical elemental tube:
3. The method according to claim 1, wherein the content is 0 to 30.0%.
It is also a method for manufacturing the seamless rectangular steel pipe described.

【0012】 D={(b−a)/a}×100 ・・・(1)式 ここで、a:楕円の長径長さ(mm) b:楕円の短径長さ(mm) 本発明では、円筒状素管の断面を一旦楕円状にしてから
角成形スタンドで熱間圧延したので、製品鋼管の断面で
角部の丸みが低減し、辺の平坦度も所望の値を満足する
ようになる。これにより、従来から使用している継目無
鋼管設備でロールを角形カリーバーを備えたものに交換
するだけで、安価に角形鋼管が量産できるようになる。
D = {(ba) / a} × 100 (1) where a: length of major axis of ellipse (mm) b: length of minor axis of ellipse (mm) Since the cross-section of the cylindrical tube was once made elliptical and then hot-rolled with a square forming stand, the roundness of the corners was reduced in the cross-section of the product steel tube, and the flatness of the side also satisfied the desired value. Become. Thus, the square steel pipe can be mass-produced inexpensively simply by replacing the rolls with the conventional steel pipe equipment having a square carry bar.

【0013】[0013]

【発明の実施の形態】図1に、本発明に係る継目無角形
鋼管の製造に用いる定形圧延機(サイザー・ミル)2の
ロール3例を示す。図1では、サイザー・ミル2が8ス
タンドあり、#1〜4スタンドまでのロール3は、圧延
時における素管断面の周長を確保するため、通常の円筒
状鋼管製造用のカリバー4(孔型)が設けられている。
そして、本発明は、#5スタンドのロールに楕円状のカ
リバーを設け、それによって、#1〜4スタンドを通過
してきた円筒状素管の断面を楕円状に成形するのであ
る。そこでほぼ周長の定まった楕円状素管1は、引き続
き#6〜8スタンドにおいて角状に成形するため、それ
らスタンドは、角形のカリバー4を有するロール3が使
用される。これによって、外側角部に対応して内側角部
が定まる。また、#6と#7スタンドのカリバー4は、
定形時に辺の凹みを防止するため、角部の曲率半径Rを
小さくしてある。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows three examples of rolls of a fixed rolling mill (sizer mill) 2 used for manufacturing a seamless rectangular steel pipe according to the present invention. In FIG. 1, the sizer 2 has eight stands, and the rolls 3 from # 1 to # 4 stand are calibers 4 (holes) for producing a normal cylindrical steel pipe in order to secure the circumferential length of the tube section during rolling. Type) is provided.
In the present invention, the elliptical caliber is provided on the roll of the # 5 stand, whereby the cross-section of the cylindrical tube passing through the # 1 to # 4 stands is formed into an elliptical shape. Then, since the elliptical base tube 1 having a substantially set peripheral length is continuously formed into a square shape in # 6 to # 8 stands, a roll 3 having a square caliber 4 is used for those stands. Thereby, the inner corner is determined corresponding to the outer corner. Also, caliber 4 of # 6 and # 7 stands,
The radius of curvature R at the corners is reduced to prevent dents on the sides at the time of the standard shape.

【0014】なお、本発明の実施に際しては、図2に示
すように、#5スタンド(図2(b)参照)で断面を楕
円された素管を、#6〜8スタンド(図2(c)及び
(d)参照)で楕円の長辺を角成形ロールのカリバー底
に向けて配置する。その結果、ロールの間隙には、楕円
の短辺が位置するので、カリバーからはみ出す肉が少な
くなり、角の鋭角が緩和される。長辺は、もとよりカリ
バー底に充満するので、形状の問題は生じないのであ
る。
In practicing the present invention, as shown in FIG. 2, a base tube having an elliptical cross section with a # 5 stand (see FIG. 2B) is replaced with a # 6 to 8 stand (FIG. 2C). ) And (d)), the long side of the ellipse is arranged toward the caliber bottom of the square forming roll. As a result, since the short side of the ellipse is located in the gap between the rolls, the flesh that protrudes from the caliber is reduced, and the acute angle is reduced. Since the long side is naturally filled with the caliber bottom, there is no shape problem.

【0015】また、本発明では、楕円状素管の楕円率を
前記のごとく1.0〜30%、好ましくは1〜5%とす
る。発明者の研究によれば、1.0%未満では、図4に
示すS値でS1>S2となり、30%を超えると、S1
<S2となって、角形鋼管の断面の左右対称性が悪くな
るからである。
Further, in the present invention, the ellipticity of the elliptical tube is set to 1.0 to 30%, preferably 1 to 5% as described above. According to the study of the inventor, when the value is less than 1.0%, S1> S2 is satisfied at the S value shown in FIG.
This is because S2 becomes poor in the left-right symmetry of the cross section of the rectangular steel pipe.

【0016】[0016]

【実施例】図6のピアサー・ミルで穿孔された種々の外
径を有する円筒状素管1に、本発明に係る製造方法を適
用して、継目無角形鋼管11を製造した。なお、該素管
1の鋼種は、JISG3466STKR400であり、
穿孔減肉・延伸圧延後の再加熱温度は、いずれも850
〜1050℃内としてある。使用したサイザー・ミル2
は、1スタンドが2ロールで8スタンドあり、各スタン
ドのロール3には、図1に示した通りのカリバー4を有
するものを使用した。つまり、#1〜#4スタンドが円
形カリバー4で、#5スタンドが楕円、#6〜#8スタ
ンドが角状カリバー4を有するロールを使用している。
表1に、#5スタンドでの楕円率を、各実施例ごとに示
す。
EXAMPLE A seamless square steel pipe 11 was manufactured by applying the manufacturing method according to the present invention to a cylindrical raw pipe 1 having various outer diameters perforated by a piercer mill shown in FIG. The steel type of the raw tube 1 is JISG3466STKR400,
The reheating temperature after piercing-thinning and elongation rolling was 850.
It is within 501050 ° C. Sizer Mill 2 used
As for the stand, there were eight stands with two rolls, and a roll 3 of each stand having a caliber 4 as shown in FIG. 1 was used. That is, the rolls having the circular caliber 4 are used for the stands # 1 to # 4, the ellipse is used for the stand # 5, and the roll having the angular caliber 4 is used for the stands # 6 to # 8.
Table 1 shows the ellipticity of the # 5 stand for each example.

【0017】[0017]

【表1】 [Table 1]

【0018】その後、表1の楕円状素管を、角成形ロー
ルで角筒に熱間圧延したが、その結果を鋼管断面の左右
角部のS値の差(図4参照)で評価し、表1に示す。つ
まり、断面形状の均一性で評価したのである。表1よ
り、楕円率が本発明の範囲にあるものは、ΔS値が満足
できる所望の値となった。
Thereafter, the elliptical tube shown in Table 1 was hot-rolled into a rectangular tube by a square forming roll. The result was evaluated based on the difference between the S values of the right and left corners of the cross section of the steel tube (see FIG. 4). It is shown in Table 1. That is, the evaluation was made based on the uniformity of the cross-sectional shape. As shown in Table 1, when the ellipticity was within the range of the present invention, the ΔS value was a desired value that could be satisfied.

【0019】[0019]

【発明の効果】以上述べたように、本発明により、断面
での角部の丸みが小さく、且つ辺の平坦な継目無角形鋼
管が、1スタンドが2ロールの定形圧延機で効率良く、
且つ安価に製造できるようになった。
As described above, according to the present invention, a seamless rectangular steel pipe having a rounded corner with a small cross-section and a flat side can be efficiently produced by a fixed-rolling mill having two rolls per stand.
In addition, it can be manufactured at low cost.

【図面の簡単な説明】[Brief description of the drawings]

【図1】本発明に係る継目無角形鋼管を成形するサイザ
ー・ミルに配置したロールのカリバー形状を示す模式図
である。
FIG. 1 is a schematic diagram showing a caliber shape of a roll arranged in a sizer mill for forming a seamless rectangular steel pipe according to the present invention.

【図2】図1の斜視図であり、(a)はサイザー・ミル
全体、(b)は#5スタンド、(c)は#6スタンド、
(d)は#8スタンドでの圧延状況である。
FIG. 2 is a perspective view of FIG. 1, wherein (a) is an entire sizer mill, (b) is a # 5 stand, (c) is a # 6 stand,
(D) is a rolling situation at the # 8 stand.

【図3】1スタンドが2ロールの角成形スタンドで、円
筒状素管より角筒に成形する時の問題点を示す図であ
り、(a)は圧延時、(b)は製品の断面である。
FIGS. 3A and 3B are diagrams showing a problem when forming a rectangular tube from a cylindrical tube into a rectangular tube, where one stand is a two-roll square forming stand, wherein FIG. is there.

【図4】本発明の実施結果を評価するΔS値の説明図で
ある。
FIG. 4 is an explanatory diagram of a ΔS value for evaluating an implementation result of the present invention.

【図5】角形鋼管の各部サイズを説明する断面図であ
る。
FIG. 5 is a sectional view illustrating the size of each part of the rectangular steel pipe.

【図6】継目無鋼管の製造設備を示すフロー図である。FIG. 6 is a flowchart showing a facility for manufacturing a seamless steel pipe.

【符号の説明】[Explanation of symbols]

1 素管(円筒状素管)又はビレット 2 定形圧延機(サイザー・ミル) 3 ロール 4 カリバー 5 加熱炉 6 ピアサー・ミル 7 エロンゲータ 8 プラグ・ミル 9 リーラ 10 再加熱炉 11 継目無角形鋼管又は角形鋼管(角筒) 12 角カリバー 13 楕円形状 DESCRIPTION OF SYMBOLS 1 Raw pipe (cylindrical raw pipe) or billet 2 Fixed rolling mill (Sizer mill) 3 Roll 4 Caliber 5 Heating furnace 6 Piercer mill 7 Elongator 8 Plug mill 9 Reeler 10 Reheating furnace 11 Seamless square steel pipe or square Steel pipe (square tube) 12 Square caliber 13 Oval shape

───────────────────────────────────────────────────── フロントページの続き (72)発明者 長濱 拓也 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 (72)発明者 豊岡 高明 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 (72)発明者 佐藤 秀雄 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 (72)発明者 森岡 信彦 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 (72)発明者 喜多 政春 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 (72)発明者 山本 健一 愛知県半田市川崎町1丁目1番地 川崎製 鉄株式会社知多製造所内 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takuya Nagahama 1-1, Kawasaki-cho, Handa-shi, Aichi Kawasaki Steel Corp. Chita Works (72) Inventor Takaaki Toyooka 1-1-1, Kawasaki-cho, Handa-shi, Aichi Kawasaki (72) Inventor Hideo Sato 1-1-1, Kawasaki-cho, Handa-shi, Aichi Prefecture Kawasaki Steel Corporation Chita Works (72) Inventor Nobuhiko Morioka 1-1-1, Kawasaki-cho, Handa-shi, Aichi Prefecture Kawasaki Inside Chita Works, Steel Works (72) Inventor Masaharu Kita 1-1-1, Kawasaki-cho, Handa City, Aichi Prefecture Inside Chita Works, Kawasaki Works (72) Kenichi Yamamoto 1-1-1, Kawasaki-cho, Handa City, Aichi Prefecture Kawasaki Inside the Chita Works of Iron and Steel Corporation

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 継目無鋼管製造設備でビレットに穿孔し
て得た円筒状素管を、1スタンドが2ロールからなる定
形圧延機で熱間圧延して角筒に成形するに際し、 前記定形圧延機のうち最初の角成形スタンドより上流側
の定形スタンドで、前記円筒状素管の断面を楕円状に成
形してから、該楕円状素管を角成形スタンドに通管して
角筒に熱間圧延することを特徴とする継目無角形鋼管の
製造方法。
1. The method according to claim 1, wherein when the cylindrical raw tube obtained by perforating a billet in a seamless steel pipe manufacturing facility is hot-rolled by a fixed-rolling machine having two rolls in one stand to form a square tube, The cross section of the cylindrical raw tube is formed into an elliptical shape on a standard stand upstream of the first square forming stand of the machine, and then the elliptical raw tube is passed through the square forming stand to heat the rectangular tube. A method for producing a seamless rectangular steel pipe, characterized by being subjected to cold rolling.
【請求項2】 前記楕円状素管の断面の長辺を、角成形
ロールに設けたカリバー底側に向けて、該楕円状素管を
熱間圧延することを特徴とする請求項1記載の継目無角
形鋼管の製造方法。
2. The elliptical tube according to claim 1, wherein a long side of the cross section of the elliptical tube is directed toward a caliber bottom provided on a square forming roll, and the elliptical tube is hot-rolled. Manufacturing method of seamless square steel pipe.
【請求項3】 前記楕円状素管の下記(1)式で定義す
る楕円率(D)を、1.0〜30.0%とすることを特
徴とする請求項1又は2記載の継目無角形鋼管の製造方
法。 D={(b−a)/a}×100 ・・・(1)式 ここで、a:楕円の長径長さ(mm) b:楕円の短径長さ(mm)
3. The seamless element according to claim 1, wherein the ellipticity (D) of the elliptical base tube defined by the following equation (1) is 1.0 to 30.0%. Manufacturing method of square steel pipe. D = {(ba) / a} × 100 (1) where a: length of major axis of ellipse (mm) b: length of minor axis of ellipse (mm)
JP27118297A 1997-10-03 1997-10-03 Making of seamless square steel pipe Pending JPH11104710A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP27118297A JPH11104710A (en) 1997-10-03 1997-10-03 Making of seamless square steel pipe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP27118297A JPH11104710A (en) 1997-10-03 1997-10-03 Making of seamless square steel pipe

Publications (1)

Publication Number Publication Date
JPH11104710A true JPH11104710A (en) 1999-04-20

Family

ID=17496499

Family Applications (1)

Application Number Title Priority Date Filing Date
JP27118297A Pending JPH11104710A (en) 1997-10-03 1997-10-03 Making of seamless square steel pipe

Country Status (1)

Country Link
JP (1) JPH11104710A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002024366A1 (en) * 2000-09-25 2002-03-28 Nakayama Corporation Method of forming cold diametrally reducing roll for metal pipe and metal pipe formed by the method
WO2004037455A1 (en) * 2002-10-22 2004-05-06 Outokumpu Oyj Method and apparatus for rolling a tube
EP1815921A1 (en) * 2004-11-26 2007-08-08 Nakata Manufacturing Company Limited Roll for molding square tube and method and device for rollingly molding square tube
EP2017019A1 (en) * 2007-07-17 2009-01-21 Tromba Maurizio snc Method and device for the manufacture of metal tubes with oval or elliptical section
CN102284547A (en) * 2011-06-23 2011-12-21 重庆大学 Method for processing rectangular aluminum alloy waveguide through multi-pass rolling drawing
CN111941088A (en) * 2020-08-06 2020-11-17 四川同一热能设备有限公司 Heat exchanger connecting pipe forming integrated machine
CN112718869A (en) * 2020-12-09 2021-04-30 天津市天元昌昊农业设施有限公司 Shaping rolling mill for steel pipe
CN113543901A (en) * 2019-03-15 2021-10-22 杰富意钢铁株式会社 Method for manufacturing seamless square steel pipe

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2002024366A1 (en) * 2000-09-25 2002-03-28 Nakayama Corporation Method of forming cold diametrally reducing roll for metal pipe and metal pipe formed by the method
WO2004037455A1 (en) * 2002-10-22 2004-05-06 Outokumpu Oyj Method and apparatus for rolling a tube
CN1329137C (en) * 2002-10-22 2007-08-01 奥托库姆普联合股份公司 Method and apparatus for rolling a tube
EP1815921A1 (en) * 2004-11-26 2007-08-08 Nakata Manufacturing Company Limited Roll for molding square tube and method and device for rollingly molding square tube
EP1815921A4 (en) * 2004-11-26 2008-07-23 Nakata Mfg Company Ltd Roll for molding square tube and method and device for rollingly molding square tube
EP2017019A1 (en) * 2007-07-17 2009-01-21 Tromba Maurizio snc Method and device for the manufacture of metal tubes with oval or elliptical section
CN102284547A (en) * 2011-06-23 2011-12-21 重庆大学 Method for processing rectangular aluminum alloy waveguide through multi-pass rolling drawing
CN113543901A (en) * 2019-03-15 2021-10-22 杰富意钢铁株式会社 Method for manufacturing seamless square steel pipe
CN113543901B (en) * 2019-03-15 2023-08-04 杰富意钢铁株式会社 Method for manufacturing seamless square steel tube
CN111941088A (en) * 2020-08-06 2020-11-17 四川同一热能设备有限公司 Heat exchanger connecting pipe forming integrated machine
CN112718869A (en) * 2020-12-09 2021-04-30 天津市天元昌昊农业设施有限公司 Shaping rolling mill for steel pipe

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