JPS5927704A - Method for controlling wall thickness of shell in mandrel mill for seamless pipe - Google Patents

Method for controlling wall thickness of shell in mandrel mill for seamless pipe

Info

Publication number
JPS5927704A
JPS5927704A JP57137902A JP13790282A JPS5927704A JP S5927704 A JPS5927704 A JP S5927704A JP 57137902 A JP57137902 A JP 57137902A JP 13790282 A JP13790282 A JP 13790282A JP S5927704 A JPS5927704 A JP S5927704A
Authority
JP
Japan
Prior art keywords
shell
mandrel
caliber
mandrel bar
rolling
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
JP57137902A
Other languages
Japanese (ja)
Inventor
Shigeo Kawabata
川畑 成夫
Shinji Akita
秋田 真次
Naoya Fushimi
直哉 伏見
Megumi Tanaka
恵 田中
Masayuki Hatanaka
畑中 政之
Morio Saito
斉藤 森生
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 Engineering Corp
Original Assignee
NKK Corp
Nippon Kokan Ltd
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 NKK Corp, Nippon Kokan Ltd filed Critical NKK Corp
Priority to JP57137902A priority Critical patent/JPS5927704A/en
Publication of JPS5927704A publication Critical patent/JPS5927704A/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B17/00Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling
    • B21B17/02Tube-rolling by rollers of which the axes are arranged essentially perpendicular to the axis of the work, e.g. "axial" tube-rolling with mandrel, i.e. the mandrel rod contacts the rolled tube over the rod length

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)

Abstract

PURPOSE:To roll a seamless pipe so as to have the specified thickness in the longitudinal direction thereof by determining the outside diameter distribution of a mandrel bar from the temp. distribution thereof in the longitudinal direction measured right after the end of rolling the seamless steel pipe and controlling the caliber heights of rolling rolls of the stands with the measured values. CONSTITUTION:The outside diameter of a mandrel bar 3 measured in the longitudinal direction thereof right after the passage of the trailing end thereof through a final stand 1 (#n) upon ending of rolling of a seamless steel pipe (shell) 2 is inputted to a calculator 6. The calculator 6 calculates the spaces between the caliber surfaces of a pair of rolling rolls 1a, 1b and the surface of the 2nd and succeeding bars 3 in each stand in accordance with said measured value. More specifically, said calculator calculates the caliber height between the rolls 1a and 1b in the respective positions in the longitudinal direction of the 2nd and succeeding bars 3 for each of the stands so that the caliber height is kept constant in the longitudinal direction of the 2nd and succeeding bars 3. The calculator 6 controls a controller 6 in accordance with the calculated values, and the controller 6 adjusts an adjuster 4 in accordance with the signal from the calculator 6.

Description

【発明の詳細な説明】 この発明は、継目無管をその長さ方向に肉厚一定になる
ように圧延することができる継目無管マンドレルミルに
おけるシェルの肉厚制御層ミに関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thickness control layer of a shell in a seamless pipe mandrel mill capable of rolling a seamless pipe so that the wall thickness is constant in the length direction of the seamless pipe.

従来、継目無管マンドレルミルの操業法においては、シ
ェル(継目無管)を、その長さ方向に肉厚一定になるよ
うに、有効に圧延する方法が確立されていなかった。
Conventionally, in the operating method of a seamless pipe mandrel mill, no method has been established for effectively rolling a shell (seamless pipe) so that the wall thickness is constant in the length direction.

そこで本発明者等は、以上のような問題な解消すべく研
究を行なった結果、次に示す通りの知見を得た。
The inventors of the present invention conducted research to solve the above-mentioned problems, and as a result, they obtained the following knowledge.

(1)、マンドレルミルによって圧延されたシェルにお
いて、その長さ方向に肉厚変化が生しる最も大きな要因
の1つとして、圧延に伴なって、マンドレルバ−の外径
が不均一に変化することが挙けられる。この外径変化は
、圧延の際における、相対画に移動するマンドレルバ−
とシェルとの間の接触面の熱伝達に伴い、マンドレルバ
ーがその長さ方向に不均一に熱膨張することによって生
じ、しかもこの変化は、同一ロット内の複数のシェルの
各々において実質的に同一である(複数本使われるマン
ドレルバーは同一規格である)。
(1) One of the biggest reasons why the wall thickness changes in the length direction of a shell rolled by a mandrel mill is that the outer diameter of the mandrel bar changes non-uniformly during rolling. This can be mentioned. This change in outer diameter is caused by the mandrel bar moving in a relative direction during rolling.
This is caused by non-uniform thermal expansion of the mandrel bar along its length due to heat transfer at the contact surface between the They are the same (mandrel bars used in multiple sizes are of the same standard).

(2) 、 従来は、マンドレルミルにおける各スタン
ド毎に、一定力リバー高さでシェルの圧延を行なってお
り、そのため、(1)で述べたように゛、圧延中ニオイ
て、マンドレルバ−外径がその長さ方向に不均一に変化
すると、各スタンドにおいて、圧延ロールのカリバー表
面とマンドレルバーの表面との間隙が、マンドレルバ−
の長さ方向に変化し、これがシェルの長さ方向の肉厚変
化に結びつ〈。
(2) Conventionally, shells were rolled at a constant force and lever height for each stand in a mandrel mill, and as a result, as mentioned in (1), there was an odor during rolling, and the outside diameter of the mandrel bar was reduced. If the caliber changes unevenly along its length, the gap between the caliber surface of the rolling roll and the surface of the mandrel bar will change at each stand.
changes in the length direction of the shell, which leads to changes in the wall thickness of the shell in the length direction.

(3)、マンドレルミルによってシェルをIEE 延終
Tした直後のマンドレルバーの長さ方向の温度分布の測
定結果の一例を第1図に示す。第1図に示すように、圧
延終了直後のマンドレルバ−の長さ方向の温度分布は、
その(進行方向下流側)先端から後端に向って、一旦単
純に増加し、そして平坦寿曲線になっている(マンドレ
ルバーの外径分布もこれと同様である)。従って、8基
のスタンド(#1〜#8で示す)からなるマンドレルミ
ルにおケル、シェル2およびマンドレルバ−3の位置と
、マンドレルバー3の長さ方向の推定温度分布との関係
の−・例を示す第2図のように、圧延途中における、マ
ンドレルバ−3の長さ方向の温度分布を推定することが
できる(マンドレルバ−の外径モその長さ方向に推定す
ることができる)。
(3) FIG. 1 shows an example of the measurement results of the temperature distribution in the length direction of the mandrel bar immediately after the shell was IEE-rolled by the mandrel mill. As shown in Figure 1, the temperature distribution in the length direction of the mandrel bar immediately after rolling is
From the tip (on the downstream side in the direction of travel) to the rear end, it simply increases, and then becomes a flat life curve (the outer diameter distribution of the mandrel bar is also similar to this). Therefore, the relationship between the positions of the shell 2 and mandrel bar 3 in a mandrel mill consisting of eight stands (indicated by #1 to #8) and the estimated temperature distribution in the length direction of the mandrel bar 3. As shown in FIG. 2, which shows an example, the temperature distribution in the length direction of the mandrel bar 3 during rolling can be estimated (the outer diameter of the mandrel bar can also be estimated in the length direction).

(4)、従って、シェルを圧延終了した直後のマンドレ
ルバ−の長さ方向の温度分布を測定して、その測定結果
からマンドレルバーの外径分布を求め、または適当な測
定手段によって、シェルを圧延終了した直後のマンドレ
ルバ−の外径分布を直接求め、かくして得られたマンド
レルバーの外径分布に基づいて、各スタンドにおける圧
延ロールのカリバー高さを、次回以降のマンドレルバー
の通過位置に対応させて変更することによって、各スタ
ンドにおいて、圧延ロールのカリバー表面と次回以降の
マンドレルバ−の表面との間隙を、次回以降のマンドレ
ルバーの長さ方向に一定にすることができ、その結果、
次回以降のマンドレルバ−に装着された新シェルを、そ
の長さ方向に肉厚一定になるように圧延することができ
る(なお、マンドレルミル通過後のシェルは、サイジン
グミルによって、所定外径、且つ真円になるように成形
される)。
(4) Therefore, immediately after rolling the shell, measure the temperature distribution in the length direction of the mandrel bar and determine the outer diameter distribution of the mandrel bar from the measurement results, or use an appropriate measuring method to roll the shell. Directly determine the outer diameter distribution of the mandrel bar immediately after finishing, and based on the outer diameter distribution of the mandrel bar obtained in this way, the caliber height of the rolling roll in each stand is made to correspond to the passing position of the mandrel bar from the next time onward. By changing this, the gap between the caliber surface of the rolling roll and the surface of the next and subsequent mandrel bars can be made constant in the length direction of the next and subsequent mandrel bars in each stand, and as a result,
The new shell attached to the next mandrel bar can be rolled so that the wall thickness is constant in the length direction (the shell after passing through the mandrel mill is rolled to a predetermined outer diameter and (shaped into a perfect circle).

この発明は、上記知見に基づいてなされたもので、複数
のスタンドからなるマンドレルミルによってシェルを圧
延終了した直後のマンドレルバーの外径を、その長さ方
向に沿って測定し、前記マンドレルバーの長さ方向に沿
った外径の測定値に基づいて、前記複数のスタンドのう
ちの少なくとも最終2スタンドの各々における圧延ロー
ルのカリバー高さを、□次回以降のマンドレルバ−の通
過位置に対応させて変更して、前1記複数のスタンドの
うちの少なくとも最終2スタンドの各々において、前記
圧延ロールのカリバー表面と前記次回以降のマンドレル
バ−の表面との間隙な、前記次回以降のマンドレルバ−
の長さ方向に一定にする継目無管マンドレルミルにおケ
ルシェルノ肉厚制御法としたことに特徴を有する。
This invention was made based on the above knowledge, and the outer diameter of the mandrel bar is measured along its length immediately after the shell has been rolled by a mandrel mill consisting of a plurality of stands. Based on the measured value of the outer diameter along the length direction, the caliber height of the rolling roll in each of at least two final stands of the plurality of stands is made to correspond to the passing position of the mandrel bar from the next time onwards. Modified, in each of at least the last two stands of the first plurality of stands, a gap between the caliber surface of the rolling roll and the surface of the next and subsequent mandrel bars.
The feature is that the Kerschelno wall thickness control method is applied to the seamless mandrel mill, which keeps the wall thickness constant in the length direction.

以下この発明を、実施例により図面を参照しながら説明
する。
The present invention will be explained below by way of examples with reference to the drawings.

第3図は、この発明にかかる方法を実施するための肉厚
制御装置の概略構成図である。図において、■は、継目
無管マンドレルミルを構成するスタンドであり、la、
Ibはその圧延ロール(カリバー付)である。図におい
ては、# ]のスタンド1と#nのスタンドlとを示し
である。2はシェル(継目無管)であり、シェル2は、
各スタンド1の1対の圧延ロールla、Jb間を通過す
る。
FIG. 3 is a schematic configuration diagram of a wall thickness control device for implementing the method according to the present invention. In the figure, ■ is a stand that constitutes a seamless mandrel mill, la,
Ib is the rolling roll (with caliber). In the figure, stand 1 of #] and stand l of #n are shown. 2 is a shell (seamless pipe), and shell 2 is
It passes between a pair of rolling rolls la and Jb of each stand 1.

3は、シェル2の中に配されたマンドレルバ−である。3 is a mandrel bar placed inside the shell 2.

かくして、シェル2は、各スタンド1を通過する際に、
1対の圧延ロールla、lbと、マンドレルバ−3とに
よって、各スタンド毎に所定肉厚となるように圧延され
る。
Thus, as the shell 2 passes through each stand 1,
Each stand is rolled to a predetermined thickness by a pair of rolling rolls la and lb and a mandrel bar 3.

4は、第4図にJ対の圧延ロールIa、Jb(7)一部
の概略関係図で示すように、各スタンド1における1対
の圧延ロール1 a+  1 b間ツカIJ ハ−高さ
Kを変更するための、圧延ロール1aに連結された、カ
リバー高さ調節機である。
4 is the height K between the pair of rolling rolls 1 a + 1 b in each stand 1, as shown in a partial schematic relationship diagram of J pairs of rolling rolls Ia and Jb (7) in FIG. This is a caliber height adjuster connected to the rolling roll 1a for changing the height of the roll.

各カリバー高さ調節機4は、カリバー高さ制御器5によ
って制御される。6は演算器である。シェル2を圧延し
終えて、最終スタンド1 (#n)をその後端が通過し
た直後のマンドレルバ−3の外径は、適当な測定手段(
図示せず)によって、その長さ方向に沿って測定され、
この測定値は、演算器6に入力される。
Each caliber height adjuster 4 is controlled by a caliber height controller 5. 6 is a computing unit. The outer diameter of the mandrel bar 3 immediately after the shell 2 has been rolled and its rear end has passed through the final stand 1 (#n) is determined by an appropriate measuring means (
(not shown) along its length;
This measured value is input to the calculator 6.

演算器6は、かくして入力されたマンドレルバ−3の長
さ方向に沿った外径の測定値に基づいて、各スタンド1
において、1対の圧延ロールla。
The calculator 6 calculates the size of each stand 1 based on the measured value of the outer diameter along the length of the mandrel bar 3 thus input.
, a pair of rolling rolls la.

Ib(7)カリバー表面と次回以降のマンドレルバ−の
表面との間隙を、次回以降のマンドレルバ−の長さ方向
に一定になるように、各スタンド毎に、次回以降のマン
ドレルバ−の長さ方向各位置における、1対の圧延ロー
ルla、Ib間のカリバー高さを演算する。
Ib (7) In order to keep the gap between the caliber surface and the surface of the mandrel bar from the next time constant in the length direction of the mandrel bar from the next time onward, for each stand, The caliber height between the pair of rolling rolls la and Ib at the position is calculated.

かくして得られた演算値に基づいて、演算器6は、カリ
バー高さ制御器5を制御し、カリバー高さ制御器5は、
演算器6からの信号によって各カリバー高さ調節機4を
制御する。その結果、新シェルの圧延に際して、前記演
算値に対応するように、各カリバー高さ調節機4は、各
スタンド】における1対の圧延ロールla、lb間のカ
リバー高さKを調節する。
Based on the calculated value thus obtained, the calculator 6 controls the caliber height controller 5, and the caliber height controller 5
Each caliber height adjuster 4 is controlled by a signal from the calculator 6. As a result, when rolling a new shell, each caliber height adjuster 4 adjusts the caliber height K between the pair of rolls la and lb on each stand in accordance with the calculated value.

なお、マンドレルバー3の外径は、その温度に対応する
ことから、最終スタンド1(#4n)通過直後のマンド
レルバ−3の長さ方向の温度を測定し、この温度測定値
に基づいて、マンドレルバ−3の長さ方向に沿った外径
を求めることができる。
Since the outer diameter of the mandrel bar 3 corresponds to its temperature, the temperature in the length direction of the mandrel bar 3 is measured immediately after passing through the final stand 1 (#4n), and based on this temperature measurement, the mandrel bar is The outer diameter along the length direction of −3 can be determined.

うに、各スタンドのカリバー高さを設定した、8基のス
゛タンドを有するマンドレルミルを準備した。
A mandrel mill with eight stands was prepared, with the caliber height of each stand set.

マンドレルバ−は、140.5 mm 9’の同一規格
のものを複数本準備した。シェルは同一ロットのものを
複数準備した。
A plurality of mandrel bars having the same standard of 140.5 mm 9' were prepared. Multiple shells from the same lot were prepared.

そして、各スタンドにおけるカリバー高さを不変にして
、1木目のシェルの圧延を行なった。その圧延終了直後
のマンドレルバ−の長さ方向の温度を測定した。この温
度測定値に基づいて、マンドレルバーの外径(分布)を
その長さ方向に沿って求めた。その−例を第5図に示す
Then, the first grain shell was rolled while keeping the caliber height unchanged on each stand. Immediately after the rolling was completed, the temperature in the longitudinal direction of the mandrel bar was measured. Based on this temperature measurement, the outer diameter (distribution) of the mandrel bar was determined along its length. An example thereof is shown in FIG.

2本目のシェルの圧延に際して、かくして得られたマン
ドレルバーの外径分布のデータに基づいて、各スタンド
毎に、マンドレルバーの長さ方向各位置に対応してカリ
バー高さを変更した。その結果得られた2本目のシェル
の長さ方向の肉厚分布を、第6図中aで示す。なお、各
スタンドにおけるカリバー高さ不変状態で圧延を行なっ
た1木目のシェルの長さ方向の肉厚分布を、比較のため
に、第6図中すで示す。
When rolling the second shell, the caliber height was changed for each stand, corresponding to each position in the length direction of the mandrel bar, based on the thus obtained data on the outer diameter distribution of the mandrel bar. The thickness distribution in the length direction of the second shell obtained as a result is shown by a in FIG. For comparison, the wall thickness distribution in the longitudinal direction of the first-grain shell, which was rolled with the caliber height unchanged on each stand, is already shown in FIG.

第5図から、この発明によって、肉厚か長き方向に一定
なシェルが得られることが明らかである。
It is clear from FIG. 5 that the invention provides a shell whose wall thickness is constant in the longitudinal direction.

以」二説明したように、この発明においては、シェル(
継目無管)を、その長さ方向に肉厚一定になるように圧
延することができる。
As explained below, in this invention, the shell (
Seamless pipes) can be rolled so that the wall thickness is constant in the length direction.

【図面の簡単な説明】[Brief explanation of the drawing]

第1図はシェルを圧延終了した直後のマンドレルバーの
長さ方向の温度分布の測定結果の一例を示す図、第2図
はシェルおよびマンドレルバーの位置とマンドレルバ−
の長さ方向の推定温度分布との関係の一例を示す図、第
3図はこの発明にかかる方法を実施するための肉厚制御
装置の概略構成図、第4図は一対の圧延ロールの−・部
の概略関係図、第5図はマンドレルバーの外径分布の一
例を示す図、第6図はシェルの長さ方向の肉厚分布を示
す図である。 出願人 日本鋼管株式会社
Figure 1 shows an example of the measurement results of the temperature distribution in the length direction of the mandrel bar immediately after the shell has been rolled, and Figure 2 shows the positions of the shell and mandrel bar and the temperature distribution of the mandrel bar.
FIG. 3 is a schematic configuration diagram of a wall thickness control device for carrying out the method according to the present invention, and FIG. 4 is a diagram showing an example of the relationship between the FIG. 5 is a diagram showing an example of the outer diameter distribution of the mandrel bar, and FIG. 6 is a diagram showing the wall thickness distribution in the longitudinal direction of the shell. Applicant Nippon Kokan Co., Ltd.

Claims (1)

【特許請求の範囲】[Claims] (1)、複数のスタンドからなるマンドレルミルによっ
てシェルを圧延終了した直後のマンドレルバ−の外径を
、その長さ方向に沿って測定し、前記マンドレルバ−の
長さ方向に沿った外径の測定値に基づいて、前記複数の
スタンドのうちの少なくとも最終2スタンドの各々にお
ける圧延ロールのカリバー高さを、次回以降のマンドレ
ルバーの通過位置に対応させて変更して、前記複数のス
タンドのうちの少なくとも最終2スタンドの各々におい
て、前記圧延ロールのカリバー表面と前記次回以降のマ
ンドレルバ−の表面との間隙を、前記次回以降のマンド
レルバ−の長さ方向に一定にすることを特徴とする継目
無管マンドレルミルにおけるシェルの肉厚制御力i大。
(1) Measure the outer diameter of the mandrel bar along its length immediately after rolling the shell with a mandrel mill consisting of multiple stands, and measure the outer diameter of the mandrel bar along its length. Based on the value, the caliber height of the rolling roll in each of the last two stands among the plurality of stands is changed in accordance with the passing position of the mandrel bar from the next time onwards, A seamless pipe characterized in that in each of at least two final stands, the gap between the caliber surface of the rolling roll and the surface of the next and subsequent mandrel bars is made constant in the length direction of the next and subsequent mandrel bars. The shell thickness control force i in a mandrel mill is large.
JP57137902A 1982-08-10 1982-08-10 Method for controlling wall thickness of shell in mandrel mill for seamless pipe Pending JPS5927704A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP57137902A JPS5927704A (en) 1982-08-10 1982-08-10 Method for controlling wall thickness of shell in mandrel mill for seamless pipe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP57137902A JPS5927704A (en) 1982-08-10 1982-08-10 Method for controlling wall thickness of shell in mandrel mill for seamless pipe

Publications (1)

Publication Number Publication Date
JPS5927704A true JPS5927704A (en) 1984-02-14

Family

ID=15209345

Family Applications (1)

Application Number Title Priority Date Filing Date
JP57137902A Pending JPS5927704A (en) 1982-08-10 1982-08-10 Method for controlling wall thickness of shell in mandrel mill for seamless pipe

Country Status (1)

Country Link
JP (1) JPS5927704A (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6114010A (en) * 1984-06-29 1986-01-22 Nippon Kokan Kk <Nkk> Method for controlling rolling with mandrel mill
WO2008123276A1 (en) 2007-03-30 2008-10-16 Sumitomo Metal Industries, Ltd. Seamless pipe manufacturing method

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6114010A (en) * 1984-06-29 1986-01-22 Nippon Kokan Kk <Nkk> Method for controlling rolling with mandrel mill
JPH0569606B2 (en) * 1984-06-29 1993-10-01 Nippon Kokan Kk
WO2008123276A1 (en) 2007-03-30 2008-10-16 Sumitomo Metal Industries, Ltd. Seamless pipe manufacturing method
EP2133159A1 (en) * 2007-03-30 2009-12-16 Sumitomo Metal Industries, Ltd. Seamless pipe manufacturing method
EP2133159A4 (en) * 2007-03-30 2011-10-26 Sumitomo Metal Ind Seamless pipe manufacturing method

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