JP3104255B2 - Hot joining method of steel - Google Patents
Hot joining method of steelInfo
- Publication number
- JP3104255B2 JP3104255B2 JP02338528A JP33852890A JP3104255B2 JP 3104255 B2 JP3104255 B2 JP 3104255B2 JP 02338528 A JP02338528 A JP 02338528A JP 33852890 A JP33852890 A JP 33852890A JP 3104255 B2 JP3104255 B2 JP 3104255B2
- Authority
- JP
- Japan
- Prior art keywords
- hot
- steel
- joining
- hot steel
- 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.)
- Expired - Fee Related
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B15/00—Arrangements for performing additional metal-working operations specially combined with or arranged in, or specially adapted for use in connection with, metal-rolling mills
- B21B15/0085—Joining ends of material to continuous strip, bar or sheet
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metal Rolling (AREA)
- Straightening Metal Sheet-Like Bodies (AREA)
- Pressure Welding/Diffusion-Bonding (AREA)
Description
【発明の詳細な説明】 （産業上の利用分野） この発明は、圧延ライン上の熱間鋼材を高歩留りでし
かも高能率に接合する方法に関する。Description: TECHNICAL FIELD The present invention relates to a method for joining a hot steel material on a rolling line with high yield and high efficiency.
（従来の技術） 製鉄工場の圧延工程では、歩留りの向上と生産性の向
上とを主目的にラインの連続化が進められている。最近
重要視されているのは、例えば500〜1200℃に熱間鋼材
（熱いままの鋼材）を圧延機の前で接合し、熱間鋼材を
連続圧延する技術である。例えば、連続圧延するために
粗圧延後の熱間コイルと仕上圧延中の熱間コイルとを溶
接または圧接によって接合する方法が、特開昭57−1095
04号公報または特開昭58−112601号公報に提案されてい
る。しかしながら、これらの方法はいずれも先行する熱
間コイルの後端（テールエンド）と後続する熱間コイル
の先端（リーディングエンド）とを切断し、その後熱間
接合する方法である。即ち、仕上圧延機において仕上圧
延中の先行する熱間コイルの後端と粗圧延機によって粗
圧延された後続する熱間コイルの先端とをシャーと称す
る切断機を用いて切断し、熱間コイルの接合端部形状を
整えた後接合する方法である。これらの接合方法によっ
て、熱間コイルの連続圧延は可能となるが、熱間コイル
の曲がりが存在する先後端を切断することは、圧延工程
での歩留り向上という目的に反し、かつ切断されたクロ
ップ（コイル鋼片）の処理に余計な工数を必要とする。(Prior Art) In a rolling process of an iron mill, continuous production of a line has been promoted mainly for improving yield and productivity. What has recently been emphasized is a technique of joining hot steel (hot steel) at, for example, 500 to 1200 ° C. in front of a rolling mill and continuously rolling the hot steel. For example, a method in which a hot coil after rough rolling and a hot coil during finish rolling are joined by welding or pressure welding for continuous rolling is disclosed in Japanese Patent Application Laid-Open No. 57-1095.
No. 04 or Japanese Patent Application Laid-Open No. 58-112601. However, each of these methods is a method in which a rear end (tail end) of a preceding hot coil and a front end (leading end) of a subsequent hot coil are cut, and then hot bonding is performed. That is, the rear end of the preceding hot coil during finish rolling in the finish rolling machine and the front end of the subsequent hot coil roughly rolled by the rough rolling machine are cut using a cutter called a shear, and the hot coil is cut. After the shape of the joining end is adjusted, the joining is performed. With these joining methods, continuous rolling of the hot coil is possible, but cutting the front and rear ends where the bending of the hot coil exists is contrary to the purpose of improving the yield in the rolling process, and the cut crop is cut. (Coil billet) processing requires extra man-hours.
一方、先行する熱間コイルの後端と後続する熱間コイ
ルの先端とを切断せずに熱間接合することは、熱間コイ
ルの端部に曲がりが存在したままであるから、後述のと
おり様々な問題を含む。On the other hand, performing hot joining without cutting the rear end of the preceding hot coil and the front end of the subsequent hot coil is because the bend remains at the end of the hot coil, as described below. Including various problems.
さて、熱間鋼材の熱間接合を能率よく行う方法として
圧接法がある。この圧接法では、従来、接合面のスケー
ルを事前に除去して清浄化することが必須であると考え
られていた。しかし、本出願人は還元雰囲気下で圧接を
行うならば、事前の脱スケールを必ずしも行わなくても
よいという知見を基にして、先に「鋼材の熱間接合方
法」の発明を特許出願した（特開平２−268748号、以
下、これを先願発明という）。As a method for efficiently performing hot joining of a hot steel material, there is a pressure welding method. In this pressure welding method, it has been conventionally considered that it is essential to remove the scale of the bonding surface in advance and clean it. However, based on the knowledge that prior descaling is not necessarily performed if pressure welding is performed in a reducing atmosphere, the present applicant has previously filed a patent application for the invention of "Hot joining method for steel materials". (Japanese Unexamined Patent Publication No. 2-268748, hereinafter referred to as a prior invention).
（発明が解決しようとする課題） 前記の先願発明の還元雰囲気下で行う熱間接合方法に
よれば、熱間鋼材の接合を簡単な方法で能率よく行うこ
とができる。しかし、熱間鋼材の後端もしくは先端に、
または後端と先端の両方に曲がりが存在すると、熱間鋼
材の重ね合わせまたは突き合わせの作業が困難となり、
時間がかかるのみではなく、熱間鋼材の重ね合わせまた
は突き合わせの精度が不足する。(Problem to be Solved by the Invention) According to the hot joining method performed in a reducing atmosphere of the prior application, the joining of hot steel materials can be efficiently performed by a simple method. However, at the rear end or front end of hot steel,
Or, if there is a bend at both the rear end and the front end, the work of overlapping or butting hot steel becomes difficult,
Not only is it time-consuming, but the accuracy of the superposition or butting of the hot steel is insufficient.
熱間鋼材の重ね合わせまたは突き合わせの精度が不足
したまま熱間接合すると、接合部の強度が不足し、次の
連続圧延工程で接合部に亀裂が発生したり、接合部が幅
方向あるいは長手方向にずれたりして、最悪の場合接合
部から破断する。When hot joining is performed while the accuracy of superposition or butting of hot steel materials is insufficient, the strength of the joint is insufficient, cracks are generated in the joint in the next continuous rolling process, and the joint is in the width direction or longitudinal direction. And in the worst case breaks from the joint.
本発明の目的は、先行熱間鋼材の後端の曲がりの部分
と後続熱間鋼材の先端の曲がりの部分を切断することな
く、重ね合わせまたは突き合わせて還元雰囲気下で熱間
接合し、次の工程の連続圧延を可能とすることにある。An object of the present invention is to superimpose or butt and hot-join under a reducing atmosphere without cutting a bent portion at a rear end of a preceding hot steel material and a bent portion at a front end of a subsequent hot steel material, and It is to enable continuous rolling of the process.
（課題を解決するための手段） 本発明は、重ね合わせまたは突き合わせを行う前に、
先行熱間鋼材の後端もしくは後続熱間鋼材の先端に、ま
たは先行熱間鋼材の後端と後続熱間鋼材の先端の両方に
曲がり矯正を施し、その後先行熱間鋼材および後続熱間
鋼材を重ね合わせまたは突き合わせて、還元雰囲気下で
加熱し圧接する鋼材の熱間接合方法を要旨とする。(Means for Solving the Problems) The present invention relates to a method for superposing or matching,
Bending straightening is applied to the rear end of the preceding hot steel or the front end of the subsequent hot steel, or to both the rear end of the preceding hot steel and the front end of the subsequent hot steel, and then the preceding hot steel and the subsequent hot steel are removed. The gist of the present invention is a method of hot joining steel materials which are superposed or butt-connected and heated and pressed under a reducing atmosphere.
ここで、熱間鋼材とは主に、粗圧延後の熱圧鋼板を意
味するが、熱間圧延棒鋼、或る種の熱間圧延形鋼などに
も本願発明は適用できる。Here, the hot steel material mainly means a hot-pressed steel sheet after rough rolling, but the present invention can also be applied to a hot-rolled steel bar, a certain type of hot-rolled section steel, and the like.
還元雰囲気とは、ArとH2の混合ガスのような還元性ガ
スで囲まれた雰囲気、またはアセチレン、プロパンガス
等の可燃性ガスが完全燃焼する量よりも少ない酸素で燃
焼するときにできる炎（「還元炎」という）を用いて接
合部を加熱すると得られる雰囲気を意味する。A reducing atmosphere, a flame that can when the atmosphere is surrounded by a reducing gas such as a mixed gas of Ar and H 2, or acetylene, and combustible gas such as propane gas burns with less oxygen than the amount to completely burn (Referred to as "reducing flame") means an atmosphere obtained by heating the joint.
熱間接合というのは、上記の熱間鋼材を、例えば圧延
ライン上で、熱いままの状態で接合することを意味す
る。The hot joining means joining the above-mentioned hot steel materials in a hot state, for example, on a rolling line.
（作用） 本発明の方法の大きな特徴は、先行熱間鋼材の後端も
しくは後続熱間鋼材の先端に、または先行熱間鋼材の後
端と後続熱間鋼材の先端の両方に、曲がり矯正を施した
後、重ね合わせまたは突き合わせて圧接する熱間接合を
行うことにある。(Action) A major feature of the method of the present invention is that the straightening is performed on the rear end of the preceding hot steel or the front end of the subsequent hot steel, or on both the rear end of the preceding hot steel and the front end of the subsequent hot steel. After applying, it is to perform hot joining which overlaps or butts and presses.
まず、端部が曲がったままの鋼板１、２を用いて、第
２図に示すように重ね合わせまたは突き合わせて熱間接
合の試験を行った。第２図の（ａ）は重ね合わせの場合
であり、第２図の（ｂ）は突き合わせの場合である。こ
の結果、端部の曲がりが大きいほど重ね合わせまたは突
き合わせに多くの時間を要し、かつその精度が不足し、
その後の連続圧延工程において接合部に亀裂が発生した
り、接合部が幅方向あるいは長手方向にずれたりして良
好な圧延ができないことが判明した。First, using the steel plates 1 and 2 whose ends were bent, as shown in FIG. 2, they were overlapped or butted to perform a hot joining test. FIG. 2A shows the case of superposition, and FIG. 2B shows the case of butting. As a result, the greater the bend at the end, the more time it takes to overlap or abut, and the accuracy is poor,
It has been found that in the subsequent continuous rolling step, cracks are generated in the joints, and the joints are shifted in the width direction or the longitudinal direction, so that good rolling cannot be performed.
つぎに、端部に曲がりのある鋼板に、第１図に示すよ
うな方法で曲がり矯正を施した後、重ね合わせまたは突
き合わせて熱間接合の試験を行った。第１図は、圧延機
６で矢印Ａの方向へ圧延中の先行熱間鋼板１の後端の曲
がりを曲がり矯正機３で矯正し、つぎに後続熱間鋼板２
の先端の曲がりを曲がり矯正機３で矯正した後、両鋼板
１、２を還元雰囲気発生装置４で還元、加熱して圧延機
５で熱間接合するラインを示している。曲がり矯正の結
果、熱間鋼板の曲がりが存在する端部を切断しなくて
も、熱間鋼板の重ね合わせまたは突き合わせの作業が容
易となり、確実な熱間接合ができ、その後の連続圧延工
程においても良好な圧延ができた。Next, a steel plate having a bent end portion was subjected to bending correction by a method as shown in FIG. 1, and then subjected to a hot joining test by overlapping or butting. FIG. 1 shows that the bending of the rear end of the preceding hot steel sheet 1 being rolled in the direction of arrow A by the rolling mill 6 is straightened by the bending straightener 3 and then the subsequent hot steel sheet 2
2 shows a line in which both the steel plates 1 and 2 are reduced and heated by the reducing atmosphere generating device 4 and then hot-joined by the rolling mill 5 after the bending of the tip of the steel plate is corrected by the bending straightening machine 3. As a result of the straightening, the work of laminating or butting the hot steel sheets becomes easy, without having to cut the end of the hot steel sheet where the bending exists, and reliable hot joining can be performed. Also good rolling was achieved.
この熱間鋼板の曲がり矯正は、例えば第１図に示すよ
うな上下ロールにより挟む方法（ロールベンダー方式）
あるいは上下プレスにより圧下する方法等がある。ロー
ルベンダー方式では、熱間鋼材を移動させながらロール
を固定したままで曲がり矯正が行える。上下プレスによ
り圧下する方法には、熱間鋼材の移動速度（圧延速度）
と同期させながら上下プレス本体をも移動させて曲がり
矯正を行う方式、およびルーパー機構を利用して熱間鋼
材の端部を静止させ、上下プレス本体を固定して曲がり
矯正を行う方式がある。This straightening of the hot steel plate is performed, for example, by a method of sandwiching the upper and lower rolls as shown in FIG. 1 (roll bender method).
Alternatively, there is a method of rolling down by a vertical press. In the roll bender method, bending correction can be performed while the roll is fixed while moving the hot steel material. The method of rolling down by the up and down press includes the moving speed (rolling speed) of hot steel.
In addition, there is a method in which the upper and lower press bodies are also moved while correcting the bending, and a method in which the end of the hot steel material is stopped using a looper mechanism and the upper and lower press bodies are fixed to perform the bending correction.
矯正は、曲がりの存在する熱間鋼材の端部のみに施せ
ばよいい。しかし、端部の曲がりの有無を常に検出して
曲がりの存在する端部のみに矯正を施すよりは、むしろ
常に端部に矯正を施した方が望ましい。曲がり矯正を施
すと、基本的に熱間接合にとって負の因子となるスケー
ル（薄いスケールまたは浮いたスケール）をも同時に除
去できるからである。また圧延の前の熱間鋼材の脱スケ
ールは必須ではないが、極端に厚いスケールは予め除去
しておくほうが望ましい。なお、本発明方法は、従来の
接合方法のように熱間鋼材の先後端の曲がった部分の切
断除去を行わないことを基本とする。しかし、特に熱間
鋼材を突き合わせて接合する場合には、接合面を矩形に
するために最小限度の端部切断を行ってもよい。更にま
た、熱間鋼材を重ね合わせて接合する場合には、先行鋼
材の後端もしくは後続鋼材の先端に、またはその両方に
開先加工を施しておくのが望ましい。あるいは、重ね合
わせ面の端部を直線形状にするために最小限度の端部切
断を行ってもよい。The straightening may be performed only on the end of the hot steel material having a bend. However, it is preferable to always correct the end rather than to always detect whether the end is bent and correct only the end where the bend exists. This is because, when the straightening is performed, a scale (a thin scale or a floating scale) which is basically a negative factor for hot bonding can be removed at the same time. Although descaling of the hot steel material before rolling is not essential, it is desirable to remove extremely thick scale in advance. The method of the present invention is based on the fact that the bent portion at the front and rear ends of the hot steel material is not cut and removed unlike the conventional joining method. However, particularly when hot steel materials are butt-joined, a minimum end cutting may be performed to make the joining surface rectangular. Furthermore, when hot steel materials are overlapped and joined, it is desirable that a groove is formed on the rear end of the preceding steel material, the front end of the succeeding steel material, or both. Alternatively, a minimum amount of end cutting may be performed in order to make the end of the superposed surface straight.
（実施例） 板厚10mm、幅300mm、長さ500mmの低炭素鋼板の端部
に、あらかじめ第３図に示すような曲がり（長さ100mm
において、最大上反り量20mm）を与え、加熱炉で1150℃
に加熱した。(Example) A low carbon steel plate having a thickness of 10 mm, a width of 300 mm, and a length of 500 mm was bent in advance as shown in FIG.
At a maximum warpage of 20mm) and heating furnace at 1150 ℃
Heated.
加熱炉から抽出後、先行熱間鋼板の後端および後続熱
間鋼板の先端に曲がりを存在させたまま第１図に示した
ような圧延ラインへ搬送した。圧延ラインは、３ロール
ベンダー、還元バーナおよびプレス圧接機からなる。After being extracted from the heating furnace, the steel sheet was conveyed to a rolling line as shown in FIG. 1 with a bend existing at the rear end of the preceding hot steel sheet and at the front end of the subsequent hot steel sheet. The rolling line is composed of a three-roll bender, a reduction burner and a press welding machine.
曲がり矯正では、３ロールベンダーを使用し、先行熱
間鋼板の後端および後続熱間鋼板の先端の両方に曲がり
矯正を施した。還元雰囲気の形成では、還元バーナを使
用し、プロパンガスの還元炎（完全燃焼させるために必
要な酸素の70％の酸素で燃焼させたときの炎）を発生さ
せ、この還元炎を接合部に直接吹きつけて加熱すること
により行った。In the straightening, a three-roll bender was used to straighten both the rear end of the preceding hot steel sheet and the front end of the subsequent hot steel sheet. In the formation of a reducing atmosphere, a reducing burner is used to generate a reducing flame of propane gas (a flame when burned with 70% of the oxygen required for complete combustion), and this reducing flame is applied to the joint. This was done by direct spraying and heating.
熱間接合では、先行熱間鋼板の後端と後続熱間鋼板の
先端とを30mm幅重ね合わせ、重ね合わせた接合部の板厚
が10mmになるまで上下プレスで圧接した。In the hot joining, the rear end of the preceding hot steel sheet and the leading end of the subsequent hot steel sheet were overlapped by 30 mm in width, and pressed by a vertical press until the thickness of the overlapped joint became 10 mm.
圧接後、接合部に曲率半径10mmの工具を押しつける常
温曲げ試験を行い、接合部の割れ率を評価した。割れ率
の定義は下記のとおりである。After pressure welding, a room temperature bending test was performed in which a tool having a radius of curvature of 10 mm was pressed against the joint, and the crack rate of the joint was evaluated. The definition of the cracking rate is as follows.
第１表に上記曲げ試験後の結果を示す。なお、第１表
で、例えば試験No.1は、還元炎中で10秒間保持して鋼板
温度を900℃とし、この温度で上下プレスで圧接を行っ
たものである。第１表に示す本発明例のNo.1〜５は、３
ロールベンダーによって端部の曲がり部がほぼ水平にな
るように矯正し、その後上下プレスで圧接し、２つの鋼
板を熱間接合したものである。比較例のNo.6〜10は、曲
がり矯正を施さずに、上下プレスで圧接し、２つの鋼板
を熱間接合したものである。なお、No.1〜10のいずれも
圧接前の脱スケールは行っていない。比較例において
は、曲がり矯正を施していないため、鋼板の重ね合わせ
が困難で、圧接するときも重ね合わせ部のずれが生じ
た。また割れ率も著しく高かった。これに対して、本発
明例では、鋼板の端部に曲がり矯正を施した後に圧接を
行なったため、鋼板の重ね合わせが容易であり、また良
好な接合部が得られ、その結果割れ率も格段に小さかっ
た。 Table 1 shows the results after the bending test. In Table 1, for example, Test No. 1 is a test in which the steel plate was held in a reducing flame for 10 seconds, the steel plate temperature was set to 900 ° C., and pressure welding was performed by a vertical press at this temperature. Nos. 1 to 5 of the present invention examples shown in Table 1
The bent portion at the end is corrected so as to be substantially horizontal by a roll bender, and then pressed by a vertical press to hot-join two steel plates. Nos. 6 to 10 of the comparative examples were obtained by hot-joining two steel plates by press-fitting with a vertical press without performing bending correction. In addition, descaling before pressure welding was not performed for any of Nos. 1 to 10. In the comparative example, since the straightening was not performed, it was difficult to overlap the steel sheets, and the overlapped portion was shifted even when pressed. The cracking rate was also remarkably high. On the other hand, in the present invention example, since the pressure welding was performed after the bending of the end portion of the steel sheet was performed, it was easy to overlap the steel sheets, and a good joint was obtained. Was small.
（発明の効果） 従来、熱間鋼材の接合においては、鋼材の端部に曲が
りが存在するため、その端部を切断することが常識であ
った。本発明の方法は、熱間鋼材の端部の曲がりの部分
を切断しなくても熱間接合を可能とする方法であり、次
工程の連続圧延を確実に行うことができるのみでなく、
圧延工程での歩留りを格段に向上させることができる。 (Effect of the Invention) Conventionally, in the joining of a hot steel material, it is common sense to cut the end portion of the steel material because the end portion is bent. The method of the present invention is a method that enables hot joining without cutting the bent portion of the end of the hot steel material, and not only can the continuous rolling in the next step be reliably performed,
The yield in the rolling process can be significantly improved.
【図面の簡単な説明】 第１図は、本発明方法の、熱間鋼材の熱間接合前に熱間
鋼材の端部に曲がり矯正を施すことを説明する概念図で
ある。 第２図は、端部に曲がりのある熱間鋼材を曲がりが存在
したままで、重ね合わせまたは突き合わせて熱間接合す
る場合の概念図である。 第３図は、実施例において使用した鋼板の曲がり量を説
明する図であり、寸法の単位はmmである。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a conceptual diagram for explaining that a bending correction is applied to an end of a hot steel material before hot joining of the hot steel material according to the method of the present invention. FIG. 2 is a conceptual diagram in the case where hot steel materials having a bend at an end are overlapped or butted and hot-joined while the bend is present. FIG. 3 is a diagram for explaining the amount of bending of the steel plate used in the example, and the unit of the dimension is mm.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) B23K 20/00 - 20/14 B21B 1/26 B21B 15/00 B21D 1/00 ────────────────────────────────────────────────── ─── Continued on the front page (58) Fields investigated (Int. Cl. 7 , DB name) B23K 20/00-20/14 B21B 1/26 B21B 15/00 B21D 1/00
Claims (1)
先行熱間鋼材の後端および／または後続熱間鋼材の先端
に曲がり矯正を施した後、先行熱間鋼材および後続熱間
鋼材を重ね合わせまたは突き合わせて、還元雰囲気下で
加熱し圧接する鋼材の熱間接合方法。1. The method according to claim 1, further comprising the steps of:
After performing bending correction on the rear end of the preceding hot steel material and / or the front end of the subsequent hot steel material, the preceding hot steel material and the subsequent hot steel material are overlapped or abutted, and heated and pressed in a reducing atmosphere to form a steel material to be pressed. Hot joining method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02338528A JP3104255B2 (en) | 1990-11-30 | 1990-11-30 | Hot joining method of steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02338528A JP3104255B2 (en) | 1990-11-30 | 1990-11-30 | Hot joining method of steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04200984A JPH04200984A (en) | 1992-07-21 |
| JP3104255B2 true JP3104255B2 (en) | 2000-10-30 |
Family
ID=18319015
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP02338528A Expired - Fee Related JP3104255B2 (en) | 1990-11-30 | 1990-11-30 | Hot joining method of steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3104255B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0520156U (en) * | 1991-07-11 | 1993-03-12 | 東北リコー株式会社 | Cable holding device for barcode scanner |
-
1990
- 1990-11-30 JP JP02338528A patent/JP3104255B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0520156U (en) * | 1991-07-11 | 1993-03-12 | 東北リコー株式会社 | Cable holding device for barcode scanner |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04200984A (en) | 1992-07-21 |
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