JP2002275537A - Hearth roll type annealing furnace for continuously annealing pipe - Google Patents

Hearth roll type annealing furnace for continuously annealing pipe

Info

Publication number
JP2002275537A
JP2002275537A JP2001074133A JP2001074133A JP2002275537A JP 2002275537 A JP2002275537 A JP 2002275537A JP 2001074133 A JP2001074133 A JP 2001074133A JP 2001074133 A JP2001074133 A JP 2001074133A JP 2002275537 A JP2002275537 A JP 2002275537A
Authority
JP
Japan
Prior art keywords
pipe
hearth roll
furnace
annealing
hearth
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.)
Withdrawn
Application number
JP2001074133A
Other languages
Japanese (ja)
Inventor
Takeo Kitaoka
武夫 北岡
Kaho Fujimoto
佳穂 藤本
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.)
Nippon Steel Nisshin Co Ltd
Original Assignee
Nisshin Steel Co 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 Nisshin Steel Co Ltd filed Critical Nisshin Steel Co Ltd
Priority to JP2001074133A priority Critical patent/JP2002275537A/en
Publication of JP2002275537A publication Critical patent/JP2002275537A/en
Withdrawn legal-status Critical Current

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  • Heat Treatments In General, Especially Conveying And Cooling (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a continuous annealing furnace for continuously annealing pipes in which the pipes are moved by hearth rolls, in which the pipe is passed through straight in the furnace to eliminate troubles such as stubbing in the furnace, and the annealing efficiency and the efficiency of straightening any bend in the following step by preventing generation of the bend during the cooling can be improved. SOLUTION: A plurality of hearth rolls are disposed in the direction orthogonal to the pipe traveling direction, and the angle of a plurality of V-shaped grooves provided in the surface of the hearth rolls are set to 80-100 deg.. The pipes can be traveled in the furnace while restricting and straightening the bend caused by the thermal distortion in the V-shaped grooves, and the bend is less even when the pipes are cooled in water.

Description

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

【0001】[0001]

【産業上の利用分野】本発明は、パイプをハースロール
により走行させながら連続的に焼鈍するための連続焼鈍
炉に関するものである。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a continuous annealing furnace for continuously annealing a pipe while traveling by a hearth roll.

【0002】[0002]

【従来の技術】溶接管等の鋼パイプは、品質を均質化す
るため、加工後連続焼鈍炉で焼鈍されている。図1に示
されるように、入側ローラーテーブル2上に載せられた
パイプPはロールの回転により順次焼鈍炉1内に挿入さ
れ、熱を受けて焼鈍され、水冷部3で水冷の後、出側ロ
ーラーテーブル4から取り出されている。このように連
続的に焼鈍しようとする時、均一加熱を行なおうとする
観点から被加熱パイプを回転させつつ炉内を走行させて
いる。図2に示すように、炉内ハースロール5をパイプ
走行方向の垂直方向に対して約3°角度を付けて取り付
け、ハースロール5を回転させることにより、被加熱パ
イプPを回転されながら炉内を走行させている。また、
曲がりを抑え、真っ直ぐに走行させるために、ハースロ
ールにV形状の溝を設けている。
2. Description of the Related Art Steel pipes such as welded pipes are annealed in a continuous annealing furnace after processing in order to homogenize quality. As shown in FIG. 1, a pipe P placed on an entrance roller table 2 is sequentially inserted into an annealing furnace 1 by rotation of a roll, and is annealed by receiving heat. It is taken out from the side roller table 4. As described above, when performing continuous annealing, the furnace is run in the furnace while rotating the pipe to be heated from the viewpoint of performing uniform heating. As shown in FIG. 2, the furnace hearth roll 5 is attached at an angle of about 3 ° with respect to the vertical direction of the pipe running direction, and by rotating the hearth roll 5, the heated pipe P is rotated while rotating the hearth roll 5. Is running. Also,
A V-shaped groove is provided on the hearth roll to suppress bending and allow the vehicle to run straight.

【0003】[0003]

【発明が解決しようとする課題】ところで、このような
ハースロール式の連続焼鈍炉でパイプを連続的に焼鈍す
る時、被焼鈍パイプが炉内に入ると、加熱により先端に
熱歪みが発生してパイプが曲がることがある。曲がった
状態で走行させると、V形状溝を外れて3°傾いたハー
スロールの垂直方向に進行し、炉壁に突っかかって通管
トラブルを発生させることに繋がる。また、走行の際、
本来のV形状溝をはずれ、次々と隣りのV形状溝にはま
り、側端のパイプが焼鈍炉側壁に突っかかって通管トラ
ブルに至ることもしばしば起こっている。このため、曲
がりが予想される方向(図2においては上方)の焼鈍炉
側壁近傍のV形状溝を予め2〜3つ空けて、すなわち通
管本数を減少させて焼鈍を行なっており、処理能力を低
下させている。さらに、曲がったパイプを炉出側での水
冷による冷却時に曲がりがさらに大きくなり、次工程で
の曲がり矯正作業が困難になっている。
When pipes are continuously annealed in such a hearth roll type continuous annealing furnace, when the pipe to be annealed enters the furnace, heat distortion occurs at the tip due to heating. Pipes may bend. When the vehicle is run in a bent state, it travels in the vertical direction of the hearth roll, which is out of the V-shaped groove and is inclined by 3 °, hits the furnace wall and leads to occurrence of a pipe trouble. Also, when traveling,
It is often the case that the original V-shaped groove is detached and then successively inserted into the adjacent V-shaped groove, and the pipe at the side end strikes the side wall of the annealing furnace, leading to a trouble in piping. For this reason, the V-shaped groove near the side wall of the annealing furnace in the direction in which the bending is expected (upward in FIG. 2) is preliminarily provided with two or three V-shaped grooves, that is, the number of passages is reduced to perform the annealing. Is decreasing. Furthermore, when the bent pipe is cooled by water cooling on the outlet side of the furnace, the bending is further increased, which makes it difficult to perform the bending correction work in the next step.

【0004】本発明は、このような問題を解消すべく案
出されたものであり、パイプをハースロールで走行させ
ながら連続的に焼鈍する炉において、パイプを真っ直ぐ
に通管させて炉内での突っかかり等のトラブルを解消す
るとともに、焼鈍処理効率と、冷却時の曲がり発生を防
止して次工程での曲がり矯正処理作業の効率を向上させ
ることができる連続焼鈍炉を提供することを目的とす
る。
The present invention has been devised in order to solve such a problem. In a furnace in which a pipe is continuously annealed while being run on a hearth roll, the pipe is passed straight through the furnace. It is an object of the present invention to provide a continuous annealing furnace which can eliminate troubles such as plunging of the steel, and can improve the annealing treatment efficiency and the bending correction processing work efficiency in the next process by preventing the occurrence of bending during cooling. And

【0005】[0005]

【課題を解決するための手段】本発明のパイプ連続焼鈍
用ハースロール式焼鈍炉は、その目的を達成するため、
複数のハースロールをパイプ走行方向に対して直角方向
に配設するとともに、該ハースロール表面に設けた複数
のV形状溝の溝角度を80〜100°に設定したもので
ある。また、ハースロールの一端を、焼鈍炉側壁部でそ
の軸方向の移動不能に軸支するとともに、他端を、焼鈍
炉他側壁部でその軸方向の移動可能に軸支してハースロ
ールの熱膨張による影響を回避した。さらに、複数のハ
ースロールを複数のグループに分割し、パイプの進行方
向後段グループのハースロール回転速度を、前段グルー
プのハースロール回転速度よりも速くして、パイプを出
側に向けて張力を付与した。
Means for Solving the Problems A hearth roll type annealing furnace for continuous pipe annealing according to the present invention has the following objects.
A plurality of hearth rolls are arranged in a direction perpendicular to the pipe running direction, and the angle of the plurality of V-shaped grooves provided on the surface of the hearth roll is set to 80 to 100 °. In addition, one end of the hearth roll is supported by the side wall of the annealing furnace so as not to be movable in the axial direction, and the other end is supported by the other side wall of the annealing furnace so as to be movable in the axial direction. Avoided the effects of expansion. Furthermore, the hearth rolls are divided into multiple groups, and the rotation speed of the hearth roll in the rear group is faster than the rotation speed of the hearth roll in the preceding group, and tension is applied to the pipe toward the outlet side. did.

【0006】[0006]

【作用および実施の態様】従来のパイプ連続焼鈍用ハー
スロール式焼鈍炉においては、前述のように、ハースロ
ールをパイプの進行直角方向に対し僅かに傾けて設置し
て、パイプを回転させながら走行させて均一加熱を行っ
ていた。本発明は、走行中のパイプを回転させず、加熱
による熱応力で曲がりが発生しても、その曲がりをパイ
プのV形状溝による拘束によって矯正しようとする発想
に基づくものである。まず、ハースロール5をパイプ走
行方向に対して直角に配置した(図面省略)。したがっ
て、ハースロールをパイプ走行方向に対して平行に回転
させると、被加熱パイプは回転されることなく走行され
る。そのために、V形状溝に沿って炉内に装入されたパ
イプは、加熱され、熱応力が発生して曲がりが起こりや
すいが、この曲がりをV形状溝の側壁により拘束し、パ
イプの自重で矯正させる。
In the conventional hearth roll type annealing furnace for continuous pipe annealing, as described above, the hearth roll is installed at a slight angle to the direction perpendicular to the direction of travel of the pipe, and the pipe runs while rotating. And uniform heating was performed. The present invention is based on the idea that even if a bend is generated by thermal stress due to heating without rotating the pipe during traveling, the bend is corrected by the constraint of the V-shaped groove of the pipe. First, the hearth roll 5 was arranged at right angles to the pipe running direction (not shown). Therefore, when the hearth roll is rotated in parallel with the pipe running direction, the heated pipe runs without being rotated. For this reason, the pipe inserted into the furnace along the V-shaped groove is heated and generates thermal stress, which is likely to bend. However, this bend is constrained by the side wall of the V-shaped groove, and the pipe is weighed by its own weight. Let it be corrected.

【0007】図3に、ハースロール表面に形成されてい
るV形状溝の溝角度を示す。従来(a)のV形状溝の溝
角度は約120°程度であったが、本発明(b)では、
その角度を80〜100°とした。この角度が小さいほ
どパイプの自重によるV形状溝の内側方向への応力負荷
の割合は大きくなって、パイプの曲がりを矯正する作用
は大きくなる。しかし、80°に満たないと曲がったパ
イプがV形状溝の壁に突っかかりやすくなり、円滑な走
行ができなくなる恐れがある。また、100°を越える
と内側方向への応力負荷割合が小さくなり自重により矯
正効果が少なくなる。
FIG. 3 shows the angle of the V-shaped groove formed on the surface of the hearth roll. Conventionally, the groove angle of the V-shaped groove in (a) was about 120 °, but in the present invention (b),
The angle was set to 80 to 100 °. The smaller the angle is, the larger the ratio of the stress load in the inward direction of the V-shaped groove due to the weight of the pipe increases, and the effect of correcting the bending of the pipe increases. However, if the angle is less than 80 °, the bent pipe tends to strike against the wall of the V-shaped groove, and there is a possibility that smooth running may not be achieved. On the other hand, if it exceeds 100 °, the ratio of the stress load in the inward direction becomes small, and the correction effect is reduced due to its own weight.

【0008】図4に、ハースロールの炉壁部における軸
支状況を説明する。従来(a)、ハースロール軸は軸方
向への熱膨張を許容するように、筒状の軸受8によって
軸方向に移動可能に軸支され、その先に回転用のスプロ
ケット9が取り付けられ、チェーン6によって回転され
ている。ハースロールの両端が軸方向に移動自在に軸支
されているために、熱を受けたとき、各ハースロールは
それぞれが統一されず思いの向きに膨張している。この
ため、炉内を走行するパイプからみると、各ハースロー
ル上のV形状溝は一直線上に並ばず、ジグザグ状となっ
て、パイプの円滑な走行を妨げたり、パイプによけいな
応力を負荷し、パイプの曲がりを助長することにもなっ
ていた。
FIG. 4 illustrates the state of the support of the hearth roll at the furnace wall. Conventionally, (a) the hearth roll shaft is axially movably supported by a cylindrical bearing 8 so as to allow thermal expansion in the axial direction, and a sprocket 9 for rotation is attached to a tip of the shaft. 6 has been rotated. Since both ends of the hearth roll are supported so as to be movable in the axial direction, when receiving heat, the hearth rolls are not unified but expand in a desired direction. For this reason, when viewed from the pipe running in the furnace, the V-shaped grooves on each hearth roll do not line up in a straight line, but form a zigzag shape, which hinders smooth running of the pipe and applies extra stress to the pipe. And it was supposed to promote the bending of the pipe.

【0009】そこで、本発明(b)では、炉壁一端の筒
状軸受8とハースロールの間のハースロール軸にスペー
サ12を嵌装した。軸受8とスプロケット9の間にもス
ペーサ12を嵌装させた。なお、ハースロール軸の他端
は従来と同じようにスペーサを嵌装させることなく筒状
の軸受により、軸方向に移動自在に軸支している。この
ように、一端を移動できないように軸支することによ
り、ハースロール軸の熱膨張は、固定していない方向の
みの一方向に揃うので、その表面のV形状溝は一方向に
一律に移動する。走行するパイプから見ると、V形状溝
は一直線上に並び、パイプは円滑に走行することになっ
て、パイプは曲がり難くなる。
Therefore, in the present invention (b), the spacer 12 is fitted on the hearth roll shaft between the cylindrical bearing 8 at one end of the furnace wall and the hearth roll. The spacer 12 was also fitted between the bearing 8 and the sprocket 9. The other end of the hearth roll shaft is movably supported in the axial direction by a cylindrical bearing without fitting a spacer as in the related art. In this way, by supporting the one end so that it cannot move, the thermal expansion of the hearth roll shaft is aligned in one direction only in the non-fixed direction, so the V-shaped groove on the surface moves uniformly in one direction. I do. When viewed from the running pipe, the V-shaped grooves are aligned, and the pipe runs smoothly, making it difficult for the pipe to bend.

【0010】本発明のさらに好ましい態様では、図5に
示すように、複数のハースロール(図面上では9本)を
複数のグループ(図面上では3つずつ、、の3つ
グループ)に分割し、パイプの進行方向後段グループの
ハースロール回転速度を、前段グループのハースロール
回転速度よりも速く(図面上ではのグループをのグ
ループよりも1〜2%速く、さらにのグループをの
グループよりも1〜2%速く)した。具体的には、ハー
スロールを回転させるスプロケットの枚数を、1枚ずつ
変えることにより、駆動チェーンの速度を変えることな
く、それぞれのハースロールの回転速度を変えることが
できる(詳細図面省略)。後段ほどハースロール回転速
度を速くすることにより、走行するパイプに出側方向に
張力が働き、パイプ走行の直進性がより向上される。
In a further preferred embodiment of the present invention, as shown in FIG. 5, a plurality of hearth rolls (nine in the drawing) are divided into a plurality of groups (three in the drawing, three groups). The hearth roll rotation speed of the rear group in the traveling direction of the pipe is higher than the hearth roll rotation speed of the previous group (1-2% faster than the group in the drawing and 1% higher than the group in the drawing). ~ 2% faster). Specifically, by changing the number of sprockets that rotate the hearth rolls one by one, the rotation speed of each hearth roll can be changed without changing the speed of the drive chain (detailed drawings are omitted). By increasing the rotation speed of the hearth roll in the later stage, tension acts on the running pipe in the outlet side direction, and the straightness of the running of the pipe is further improved.

【0011】上記のように、ハースロールの設置角度お
よびハースロール上に設けたV溝の形状を変更するとと
もに、ハースロール固定方法ならびに駆動方法を変更す
ることにより、本発明の実施後10ヶ月経ても、炉内で
のパイプの突っかかりによる走行トラブルの発生は全く
ない。また、冷却時の曲がりもほとんどなくなった。さ
らに、焼鈍炉の側壁近傍に空きスペースを設ける必要が
なくなったので、処理能力が2割アップした。従来は、
小径管通管時、曲がり発生により7〜8割の割合でパイ
プが斜めに走行し、炉壁に突っかかって走行トラブルに
なるため、炉内監視が必要であった。本改善により、走
行トラブルがなくなり、監視業務分の作業負担減となっ
た。
As described above, by changing the installation angle of the hearth roll and the shape of the V-groove provided on the hearth roll, and changing the hearth roll fixing method and the driving method, 10 months after the practice of the present invention, However, there is no running trouble caused by the pipe sticking in the furnace. In addition, bending during cooling was almost eliminated. Further, since it is not necessary to provide an empty space near the side wall of the annealing furnace, the processing capacity is increased by 20%. conventionally,
When the small-diameter pipe is passed, the pipe runs obliquely at a rate of 70 to 80% due to the occurrence of a bend, and runs into a furnace wall to cause a trouble, so that monitoring in the furnace was necessary. This improvement eliminated running troubles and reduced the workload for monitoring work.

【0012】[0012]

【発明の効果】以上に説明したように、本発明では、ハ
ースロール設置角度およびV形状溝の溝角度の変更によ
り、パイプを回転させることなく真っ直ぐに通管させて
炉内での突っかかり等のトラブルを解消するとともに、
焼鈍処理効率と、冷却時の曲がり発生を防止して次工程
での曲がり矯正処理作業の効率を大幅に向上させること
ができた。
As described above, according to the present invention, by changing the setting angle of the hearth roll and the groove angle of the V-shaped groove, the pipe is made to pass straight without rotating, and the pipe is struck in the furnace. To solve the problems of
The efficiency of annealing treatment and the prevention of bending at the time of cooling were able to be greatly improved, and the efficiency of the bending correction processing work in the next step could be greatly improved.

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

【図1】 ハースロール式連続焼鈍炉で焼鈍を行う概念
FIG. 1 is a conceptual diagram of annealing performed in a hearth roll type continuous annealing furnace.

【図2】 ハースロール式連続焼鈍炉の、従来のハース
ロール配設状況を示す図
FIG. 2 is a diagram showing a conventional hearth roll installation state of a hearth roll type continuous annealing furnace.

【図3】 ハースロール表面に設けたV形状溝のV角度を
示す縦断面、従来のものと(a)と、本発明によるもの
(b)
FIG. 3 is a longitudinal section showing the V-angle of a V-shaped groove provided on the surface of a hearth roll, the conventional one, (a) and the present invention (b).

【図4】 ハースロールの炉壁端部における支持構造を
示す断面図、従来のもの(a)と、本発明によるもの
(b)
FIG. 4 is a cross-sectional view showing a supporting structure of a hearth roll at an end of a furnace wall, a conventional one (a) and a one according to the present invention (b).

【図5】 ハースロール駆動方法を説明する概念図FIG. 5 is a conceptual diagram illustrating a hearth roll driving method.

【符号の説明】[Explanation of symbols]

P:被焼鈍パイプ 1:焼鈍炉 2:入り側ローラーテーブル 3:水
冷部 4:出側ローラーテーブル 5:ハースロール
6:駆動チェーン 7:ライン方向 8:軸受 9:スプロケット
10:冷却水用穴 11:冷却水入り側 12:スペーサー 13:キ
ャップ 14:ボルト
P: Annealed pipe 1: Annealing furnace 2: Inlet roller table 3: Water cooling section 4: Outlet roller table 5: Hearth roll
6: Drive chain 7: Line direction 8: Bearing 9: Sprocket
10: Cooling water hole 11: Cooling water entering side 12: Spacer 13: Cap 14: Bolt

Claims (3)

【特許請求の範囲】[Claims] 【請求項1】 複数のハースロールをパイプ走行方向に
対して直角方向に配設するとともに、該ハースロール表
面に設けた複数のV形状溝の溝角度を80〜100°に
したことを特徴とするパイプ連続焼鈍用ハースロール式
焼鈍炉。
1. A plurality of hearth rolls are disposed in a direction perpendicular to a pipe running direction, and a plurality of V-shaped grooves provided on a surface of the hearth roll have a groove angle of 80 to 100 °. Hearth roll annealing furnace for continuous pipe annealing.
【請求項2】 ハースロールの一端を、焼鈍炉側壁部で
その軸方向の移動不能に軸支するとともに、他端を、焼
鈍炉他側壁部でその軸方向の移動可能に軸支した請求項
1に記載のパイプ連続焼鈍用ハースロール式焼鈍炉。
2. The hearth roll has one end pivotally supported by the side wall of the annealing furnace so as not to be movable in the axial direction, and the other end supported by the other side wall of the annealing furnace so as to be movable in the axial direction. 2. A hearth roll type annealing furnace for continuous pipe annealing according to 1.
【請求項3】 複数のハースロールを複数のグループに
分割し、パイプの進行方向後段グループのハースロール
回転速度を、前段グループのハースロール回転速度より
も速くした請求項1または2に記載のパイプ連続焼鈍用
ハースロール式焼鈍炉。
3. The pipe according to claim 1, wherein the plurality of hearth rolls are divided into a plurality of groups, and the hearth roll rotation speed of the rear group in the traveling direction of the pipe is higher than the hearth roll rotation speed of the preceding group. Hearth roll type annealing furnace for continuous annealing.
JP2001074133A 2001-03-15 2001-03-15 Hearth roll type annealing furnace for continuously annealing pipe Withdrawn JP2002275537A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2001074133A JP2002275537A (en) 2001-03-15 2001-03-15 Hearth roll type annealing furnace for continuously annealing pipe

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010255910A (en) * 2009-04-23 2010-11-11 Sanken Sangyo Co Ltd Roller hearth type continuous furnace
CN102140611A (en) * 2011-03-18 2011-08-03 上海海隆石油管材研究所 135 steel-level drill rod connector and heat treatment process thereof
JP2012197960A (en) * 2011-03-18 2012-10-18 Mitsubishi Heavy Ind Ltd Heat treatment system, and heat treatment method
JP2018119170A (en) * 2017-01-23 2018-08-02 大同プラント工業株式会社 Method and apparatus for quenching

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010255910A (en) * 2009-04-23 2010-11-11 Sanken Sangyo Co Ltd Roller hearth type continuous furnace
CN102140611A (en) * 2011-03-18 2011-08-03 上海海隆石油管材研究所 135 steel-level drill rod connector and heat treatment process thereof
JP2012197960A (en) * 2011-03-18 2012-10-18 Mitsubishi Heavy Ind Ltd Heat treatment system, and heat treatment method
JP2018119170A (en) * 2017-01-23 2018-08-02 大同プラント工業株式会社 Method and apparatus for quenching

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