JP4047470B2 - Steel strip joining method - Google Patents

Steel strip joining method Download PDF

Info

Publication number
JP4047470B2
JP4047470B2 JP33996998A JP33996998A JP4047470B2 JP 4047470 B2 JP4047470 B2 JP 4047470B2 JP 33996998 A JP33996998 A JP 33996998A JP 33996998 A JP33996998 A JP 33996998A JP 4047470 B2 JP4047470 B2 JP 4047470B2
Authority
JP
Japan
Prior art keywords
steel
welding
steel strips
steel strip
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.)
Expired - Lifetime
Application number
JP33996998A
Other languages
Japanese (ja)
Other versions
JP2000158165A (en
Inventor
雅謙 竹本
康治 田中
満 岡本
庸夫 佐々木
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 Corp
Original Assignee
Nippon 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 Nippon Steel Corp filed Critical Nippon Steel Corp
Priority to JP33996998A priority Critical patent/JP4047470B2/en
Publication of JP2000158165A publication Critical patent/JP2000158165A/en
Application granted granted Critical
Publication of JP4047470B2 publication Critical patent/JP4047470B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2101/00—Articles made by soldering, welding or cutting
    • B23K2101/18—Sheet panels
    • B23K2101/185—Tailored blanks
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K2103/00—Materials to be soldered, welded or cut
    • B23K2103/02—Iron or ferrous alloys
    • B23K2103/04—Steel or steel alloys

Description

【０００１】
【発明の属する技術分野】
本発明は板厚や強度或いは性質などの異なる複数の鋼帯を、その長手方向の端部を溶接しプレス成形用に供される鋼帯の接合方法に関するものである。
【０００２】
【従来の技術】
従来、自動車部品の製造において、深絞り成形、張出し成形等成形性が要求される自動車部品あるいは高強度が要求される自動車部品毎に、その要求に応じた鋼板をプレス成形して自動車部品を製造していたが、自動車部品の中には、成形性が厳しく要求される部位とそれ程成形性が要求されない部位とを備えた自動車部品や高強度が厳しく要求される部位とそれ程高強度が要求されない部位を備えた自動車部品等がある。このような自動車部品を製造する場合、従来は要求される性能に耐えられる一枚の鋼板を用いてプレス成形を行い、成形後の自動車部品を溶接して自動車を製造していた。
【０００３】
また、最近では自動車部品の製造において、必要な部位に必要な板厚と強度を持たせるために、板厚あるいは強度の異なる鋼板をレーザー等で接合して一枚の鋼板となし、その後一体でプレスに供するという、いわゆるテーラードブランクと呼ばれる方法が注目されてきており、このような方法は、例えば、特開平７−２９０１８２号、特開平８−１７４２４６号公報等に見ることができる。また、亜鉛メッキ鋼帯同士をレーザービームで突き合わせ溶接する方法も特公平５−２５５９６号公報などにより公知となっている。
【０００４】
【発明が解決しようとする課題】
しかしながら、同一素材の一枚の鋼板を用いて自動車部品を成形する方法では、成形する自動車部品に要求される成形性がそれ程要求されない部位まで優れた成形性を有することになり、言い換えれば、素材のオーバーアクションとなるもので、それに伴う素材費のコストアップとなる問題を有していた。また、特開平７−２９０１８２号公報、特開平８−１７４２４６号公報などにより知られるテーラードブランク法は、鋼板を小さな形状に剪断し、これを接合して一枚の鋼板とするために生産性が高められないという課題を有しており、更に、溶接開始端と終了端では接合品質が安定せず、この部分を切り捨てなければならず、製品の歩留りが悪いという欠点を有しており、一方、前述した特公平５−２５５９６号公報に記載された方法では接合が満足するものでなく、有利な接合方法の出現が待たれているところである。
【０００５】
【課題を解決するための手段】
前記した要望に応えることを目的として完成された本発明に係る鋼帯の接合方法の基本構成は、 ３条の異なる鋼帯１、２、３のエッジ部を連続的に溶接するに際し、鋼帯１、２の溶接を行わない側の端部の一方に、鋼帯の端部位置決め装置を設置し、鋼帯１、２を、溶接ロ−ルと、前記端部位置決め装置を設置してある方向に押付力が働くように同一方向に傾斜して配置する複数の押さえロ−ルとの間を通過させることにより鋼帯に幅方向の力を加えて鋼帯１、２のエッジ部端面に押付力が働くようにしながらレ−ザ−溶接し、次いで、溶接された鋼帯１、２と鋼帯３を、別の溶接ロ−ルと、前記押さえロ−ルと同一方向に傾斜して配置する別の複数の押さえロ−ルとの間を通過させることにより鋼帯に幅方向の力を加えて鋼帯１、２と鋼帯３のエッジ部端面に押付力が働くようにしながらレ−ザ−溶接することにある。また、このような方法において、レ−ザ−溶接する溶接点の上流側にフランジロ−ルを配置して鋼帯の間に隙間を設けるようにしてあることを特徴とする鋼帯の接合方法を請求項２に係る発明とする。
【０００６】
即ち、本発明は、自動車部品に供される鋼板を同一素材の一枚の鋼板とするのではなく、プレス成形する前に板厚や強度或いは性質などの異なる素材を鋼帯のまま溶接しておき、これより成形しようとする自動車部品が要求する成形性あるいは強度を必要な部位に具備する鋼板を得る鋼帯の接合方法であり、しかも、異質の鋼板を小さな形状に剪断した後、これらの端部を突き合わせて接合するという生産性が悪い方法に代え、コイルから捲戻された３条の異なる鋼帯の端部同士を連続的に溶接することにより、生産性が良好でしかも鋼帯の端部の形状精度が悪い場合でも接合品質が良好となる極めて有利となる鋼帯の接合方法を提供することにある。なお、本発明により得られた鋼帯から製造される自動車部品としては、自動車の骨格構造部位などの柱状に近い部品あるいはフロアなどの異種材が平行に接合されて使用される可能性のある部品などがあり、本発明方法によってこれらの部品の飛躍的生産性と歩留りの向上を図ることができることとなる。
【０００７】
【発明の実施の形態】
本発明は前記したように、材質、板厚等の異なる３条の鋼帯１、２、３のエッジ部を連続的に有利に溶接する鋼帯の接合方法であり、その大きな特徴とするところは、傾斜する押さえロールを鋼帯１、２に押しつけることにより鋼帯の幅方向に力を加えて鋼帯のエッジ間に押付力が働くようにして溶接し、次いで、溶接された鋼帯１、２と鋼帯３を前述したと同様に傾斜する押さえロールを用いてエッジ間に押付力が働くようにして溶接位置が異にして溶接し、３条の鋼帯１、２、３の溶接を容易にして生産性と共に、接合品質が良好となる接合を可能とした点にある。
【０００８】
以下、図１〜図８を参照しながら本発明を詳細に説明する。
本発明では材質、板厚等の異なる３種類の鋼帯１、２、３のエッジ部を連続的に接合するものであり、先ず、鋼帯１、２を並べて上側の押さえロール４ａ、５ａと、これら押さえロール４ａ、５ａに比べて大径の溶接ロール７ａとの間を通過させる。このとき鋼帯１、２は大径の溶接ロール７ａ側に巻き付けて通過するものであるが、前記押さえロール４ａ、５ａは鋼帯１、２の進行方向と直交するよう配置されている溶接ロール７ａの長手方向に対してそれぞれ角度θ1 、θ2 だけ傾斜させて配置されるようにし、鋼帯１、２に幅方向の力が積極的に加えられるようにして溶接ロール７ａに押し付ける。
【０００９】
このように本発明では、押さえロール４ａ、５ａを傾斜させておくことにより鋼帯１、２に幅方向の力を積極的に加え、溶接する鋼帯１、２のエッジ間に面圧を働かせることを大きな特徴としている。鋼帯１、２の端部を突き合わせてレーザー溶接する際、溶接する鋼帯１、２の間に隙間が発生すると溶接後にアンダーカット等の品質不良が発生しやすくなる。しかし、通常、鋼帯を製造する際には鋼帯幅精度や鋼帯端部の形状品位を確保するために、鋼帯中央部をスリットしたり、端部をトリミングするなどの端部の剪断加工により仕上げるが、鋼帯端部には微少な凹凸が残るため、これらの端面を突き合わせた場合に多少の隙間が発生し、更に、レーザー溶接を行う場合、溶接部の熱収縮により鋼帯の突き合わせ面を押し開こうとする力が加わるため溶接部上流近傍では隙間が発生する。そこで、本発明では押さえロール４ａ、５ａを傾斜させ、鋼帯１、２に幅方向の力を加え、溶接する鋼帯１、２の端部に突き合わせ力を与えることにより、熱収縮による隙間を押しつけ、更に、鋼帯端部の凸部の弾性変形もしくは塑性変形を加え、凹凸による隙間についても著しく低減させることにより、溶接点において、鋼帯１、２の端部間の隙間を著しく小さくすることができ、安定した溶接品質の確保を可能とするものである。
【００１０】
この際、鋼帯の幅方向の力を与えるには、通常、サイドガイドロール等の鋼帯の溶接しない側の端部から力を加える方法が一般的に考えられるが、自動車部品に用いられるような薄手の鋼帯に対しては、これらの方法では大きな力を加えると鋼帯の座屈や端部の耳荒れ等を発生するため大きな力を加えることができず、十分に前述の溶接する鋼帯の端部間の隙間を小さくすることができないという問題があった。そこで、本発明では鋼帯１、２に幅方向の力を加えるのに押さえロール４ａ、５ａを傾斜させて押しつけるという方法を採用し、押さえロール４ａ、５ａの押し付ける力と傾斜角度を適正に調整することにより、鋼帯１、２の座屈や端部の耳荒れを発生させることなく十分な押し付ける力を自動車部品に用いられるような薄手の鋼帯にも与えることができるようにする。
【００１１】
また、本発明では鋼帯１、２の溶接を行わない側の端部の一方に、鋼帯の端部位置決め装置を設置し、押さえロール４ａ、５ａをそれぞれの鋼帯１、２が前記端部位置決め装置を設置してある方向に押付力が働くように傾斜させておくもので、このために押さえロール４ａ、５ａを同一方向に傾斜させることも特徴としている。即ち、鋼帯１と鋼帯２の接合面１０ａに対して、一般的には接合面１０ａに向かって両側より押しつける力を働かせて接合するものであるが、本発明では鋼帯１と鋼帯２共に同一方向に押付力を働かせるようにしたものであり、そのために、押さえロール４ａ、５ａは共にそれぞれ同じ方向の角度θ1 、θ2 だけ傾斜させるものとしてある。接合面１０ａに向かって両側より押付力を働かせるのは、接合面１０ａが常に溶接位置に変動しないように両側よりに押付力をバランス良く調整する必要があるが、その両側よりの押付力を調整することが難しく、本発明の如く、端部位置決め装置側の鋼帯１に対し、押さえロール４ａをθ1 傾けて押しつけることにより鋼帯１の端部位置決め装置側の端部を端部位置決め装置に押し付け、鋼帯１の幅方向位置を安定させることができることとなる。さらに、押さえロール５ａをθ2 傾けて押し付けることにより鋼帯１の溶接端部に押し付けられる鋼帯２の幅方向位置も安定することから、接合面１０ａと溶接位置が変動しないように調整することが極めて容易とする知見より成されたものである。また、溶接する鋼帯端部間の押付力は押さえロール５ａの押し付け力と傾斜角θ2 を調整することにより容易に制御することができ、さらにまた、鋼帯１、２を大径の溶接ロール７ａに巻き付けるのは鋼帯１、２の厚み方向の突き合わせ精度を良く合わせることが可能となるもので、巻き付けをしないと鋼帯１、２と溶接ロール７ａの間の空間ができやすく、鋼帯１と鋼帯２の厚み方向の突き合わせ精度が十分でない可能性が高いからである。
【００１２】
本発明はレーザービーム８ａを照射する固定されたレーザー発射管９ａの位置に対して、溶接される接合面１０ａが常に溶接位置になるように種々の検討を行い、その結果、通常の発想とは大きく異なる本発明に至ったものである。即ち、通常は接合面１０ａの位置が溶接位置から変動しないように接合面１０ａを中心に、その位置へ両側から押付力が鋼帯に与える発想がなされるものであるが、本発明では鋼帯１、２の一側に鋼帯が移動するよう押付力を付与する発想よりなされたものである。例えば、図１の示す如く、端部位置決め装置として鋼帯１の外側にエッジガイド１１ａ、１１ｂ、１１ｃを設け、そのエッジガイド１１ａ、１１ｂ、１１ｃの方向へ鋼帯１が移動するよう傾斜した押さえロール４ａを溶接ロール７ａの上部に設ける。押さえロール４ａは、例えば、シリンダーなどにより溶接ロール７ａへ押さえる力を与え、鋼帯１を拘束しながら鋼帯１を矢印の方向へ移動させる。このとき押さえロール４ａは角度θ1 だけ傾斜しているので、鋼帯１はエッジガイド１１ａ、１１ｂへ押し付けられるものである。なお、鋼帯１のエッジが損傷しないように押さえロール４ａは押し付け力と角度θ1 を調整できるようにしている。また、鋼帯１がエッジガイド１１ａ、１１ｂに拘束された時、鋼帯１の溶接される接合面１０ａの位置が溶接位置となるようにエッジガイド１１ａ、１１ｂを鋼帯１の幅方向の調整が可能としている。
【００１３】
このように鋼帯１を巾方向の位置調整するものであるが、同様に鋼帯２を角度θ2 だけ傾斜させた押さえロール５ａにより拘束した状態で移動させ、且つ、θ2 と押さえロール５ａの押さえ力を適度に調整することにより、鋼帯２の接合面１０ａが鋼帯１の接合面１０ａに適度な押付力を働かせるようにし、鋼帯１、２のエッジ面の面圧を立て、隙間を押し潰した状態で溶接することとなり、言い換えれば、ピンチ方式の突き合わせをすることにより、溶接品質が向上し、極めて有利なものである。かくすることにより、一方向への押付力を考慮するのみで、鋼帯１、２の接合位置が精度良く調整できると共に、鋼帯１、２のエッジ間に面圧を立てて溶接することとなり溶接品質が向上するものである。このように鋼帯１、２の接合面１０ａを溶接位置へ調整した後にレーザー発射管９ａよりレーザービーム８ａを照射して溶接し、鋼帯１、２を接合する。
【００１４】
このように鋼帯１と鋼帯２を溶接した後、溶接された鋼帯１、２と鋼帯３を、別の溶接ロール７ｂと、傾斜して配置する別の複数の押さえロール４ｂ、５ｂ、６との間を通過させることにより鋼帯に幅方向の力を加えて鋼帯１、２と鋼帯３のエッジ端面に押付力が働くようにしながらレーザー溶接するものである。
即ち、鋼帯１と鋼帯２とを溶接したのと同様に、溶接された鋼帯１、２に鋼帯３を溶接するものであり、角度θ3 、θ4 だけ傾斜した押さえロール４ｂ、５ｂを溶接ロール７ｂの上部に設け、該押さえロール４ｂ、５ｂにより溶接ロール７ｂへ押さえる力を与え、鋼帯１、２をエッジガイド１１ｂ、１１ｃの方向へ移動させる。同様に、鋼帯３を角度θ5 だけ傾斜した押さえロール６により拘束した状態で移動させ、且つ、θ5 と押さえロール６の押さえ力を適度に調整することにより、鋼帯３の接合面１０ｂが鋼帯１、２の接合面１０ｂに適度な押付力を働かせるようにし、鋼帯１、２と鋼帯３のエッジ面に面圧を立て、隙間を押し潰した状態で溶接することとなり、溶接品質が向上し、極めて有利なものである。
なお、押さえロール４、５、６は図３、図４に示す如く、鋼帯１、２、３毎に４個用いてもよく、その配置形態は種々考えられるが、特にこだわるものではない。
【００１５】
また、溶接ロール７ａは図５に示す如く、溶接位置に相当する箇所に溝１２ａを設けたものとして、溶接時における溶接ロール７ａの熱影響による損傷を防止するものとしている。この図５では厚みの異なる鋼帯１、２、３の接合を示しているが、溶接ロール７ａの径が全長にわたって同一径としているために鋼帯１、２は鋼帯１、２の下面に合わせて溶接するようにしている。なお、図６では鋼帯１、２の上面の合わせて溶接し、図７では厚い鋼帯１の厚みの中央に薄い鋼帯２を溶接しているものであるが、このような接合の形態は溶接ロール７の溝１２ａを挟んで左右の径を変えた溶接ロール７ａを用いるようにすれば容易になされるものである。また、溶接ロール７ａの左右の径を可変するのは溶接ロール７ａを拡縮自在とするようにしてもよくその手段は特にこだわるものではない。なお、図５〜図７により溶接ロール７ａを例にして溝１２ａについて述べたが、溶接ロール７ｂについても溶接位置に相当する箇所に溝１２ｂ（図示せず）が設けられており、溶接ロール７ｂについても溶接ロール７ａとその形態は同様である。
【００１６】
さらに、本発明では図８に示す如く、溶接点１３ａの上流側にフランジロール１４ａを配置して鋼帯１、２の間に隙間を設けるようにしている。また、本発明は鋼帯１、２を同一平面上で通板し、溶接点１３ａへ搬送するものであるが、その為に、鋼帯１、２の接合面１０ａが擦れたり、鋼帯１と鋼帯２が重なる場合があるので、それを防止するために鋼帯１、２間にフランジロール１４ａを設けることはより好ましいものである。なお、溶接点１３ｂの上流側にもフランジロール１４ｂを設けることは同様により好ましいものである。
【００１７】
なお、本発明に用いる押さえロール４、５、６は、それぞれ角度θ1 〜θ5 傾斜させるものであるが、角度θ1 〜θ5 は共に２°〜２５°が好ましく、また、押さえロール４、５、６の押さえ力は３５０Ｎ〜２００００Ｎが好ましい。その理由は、角度θ1 〜θ5 が２°未満もしくは押さえ力が３５０Ｎ未満では、鋼帯１、２、３の幅方向への押付力が不足して溶接品質が好ましくなく、角度θ1 〜θ5 が２５°超もしくは押さえ力が２００００Ｎ超では押付力が大きくなりすぎ、鋼帯１、２、３の座屈等が発生する場合があるからである。但し、角度や押さえ力の前記した範囲は好ましい範囲を述べたに過ぎないもので、座屈等の発生がなければこの範囲にこだわるものでない。
また、本発明の３条の異なる鋼帯とは、隣接する鋼帯の材質とか板厚等を異にしているものであり、両端の鋼帯が同一で中央の鋼帯が異なるものも対象としているものである。
【００１８】
【実施例１】
常法に従い製造された表１に示す化学成分の板厚０．７ｍｍ、幅２５０ｍｍの鋼帯１と板厚１．４ｍｍ、幅６９０ｍｍの鋼帯２と、板厚０．７ｍｍ、幅２５０ｍｍの鋼帯３を準備し、２ｋｗのレーザー溶接機にて１．７ｍ／分の速度で鋼帯１と鋼帯２を接合し、次いで、溶接された鋼帯１、２に鋼帯３を２ｋｗのレーザー溶接機にて１．７ｍ／分の速度で接合した。
以下、鋼帯の成分を表１に示し、接合条件および溶接結果を表２、３に示す。
【００１９】
【表１】

Figure 0004047470
【００２０】
【表２】
Figure 0004047470
【００２１】
【表３】
Figure 0004047470
上表から明らかなように、本発明によると座屈の発生もなく、アンダーカットの発生もなく、極めて良好な溶接品質が得られる。
【００２２】
【実施例２】
実施例１で示す鋼帯１と鋼帯２と鋼帯３を自動車部品（センターピラー）に成形すべく、各々１０００ｍｍに切断した。この場合、本発明は鋼帯１、２、３を接合した後に切断し、比較例では鋼帯１、２、３を切断した後に鋼板を接合した。その時の所要時間を表４に示す。
【００２３】
【表４】
Figure 0004047470
表４に示すように、本発明によると比較例で示す切板接合法に比べると、生産性も飛躍的に向上することが判る。
【００２４】
【発明の効果】
前記説明から明らかなように本発明によれば、自動車部品等をテーラードブランク法で製造する際、溶接品質が良好で、しかも、生産性の良い鋼帯の接合が可能となり、その効果は極めて大きいものである。
【図面の簡単な説明】
【図１】 本発明方法の平面説明図である。
【図２】 図１に示す本発明方法の側面説明図である。
【図３】 押さえロールを多くした本発明方法の平面説明図である。
【図４】図３に示す本発明方法の側面説明図である。
【図５】 本発明方法の溶接近傍を示す拡大説明図である。
【図６】 本発明方法の溶接近傍を示す拡大説明図である。
【図７】 本発明方法の溶接近傍を示す拡大説明図である。
【図８】本発明方法の溶接点上流側にフランジロールを具備した状態の説明図である。
【符号の説明】
１ 鋼帯１
２ 鋼帯２
３ 鋼帯３
４ 押さえロール
５ 押さえロール
６ 押さえロール
７ 溶接ロール
８ レーザービーム
９ レーザー発射管
10 接合面
11 エッジガイド
12 溝
13 溶接点
14 フランジロール[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for joining steel strips that are used for press forming by welding a longitudinal end portion of a plurality of steel strips having different thicknesses, strengths, or properties.
[0002]
[Prior art]
Conventionally, in the production of automobile parts, automobile parts are manufactured by press-molding steel sheets according to the requirements of automobile parts that require formability such as deep drawing and stretch forming or automobile parts that require high strength. However, some automotive parts are not required to have high strength and parts that require parts that require high formability and parts that do not require formability. There are car parts with parts. In the case of manufacturing such automobile parts, conventionally, a single steel plate that can withstand the required performance is used for press forming, and the automobile parts after forming are welded to manufacture the automobile.
[0003]
Recently, in the production of automobile parts, in order to give the necessary thickness and strength to the necessary parts, steel plates with different thicknesses or strengths are joined with a laser or the like to form a single steel plate, and then integrated together. A so-called tailored blank, which is used for pressing, has attracted attention. Such a method can be found in, for example, JP-A-7-290182 and JP-A-8-174246. A method for butt welding galvanized steel strips with a laser beam is also known from Japanese Patent Publication No. 5-25596.
[0004]
[Problems to be solved by the invention]
However, in the method of forming an automobile part using a single steel sheet of the same material, the formability required for the automobile part to be molded will have excellent formability up to a part that is not required so much, in other words, the material There was a problem that the material cost would be increased. In addition, the tailored blank method known from JP-A-7-290182, JP-A-8-174246, etc. has a high productivity because the steel plates are sheared into small shapes and joined to form a single steel plate. In addition, there is a problem that the welding quality is not stable at the start and end of welding, and this part has to be discarded, resulting in poor product yield. However, the method described in the above-mentioned Japanese Patent Publication No. 5-25596 does not satisfy the joining, and the advent of an advantageous joining method is awaited.
[0005]
[Means for Solving the Problems]
The basic structure of the method for joining steel strips according to the present invention completed for the purpose of satisfying the above-mentioned demand is that when continuously welding the edge portions of steel strips 1, 2, and 3 having three different strips, The end positioning device of the steel strip is installed on one of the end portions on the side where the welding is not performed, and the steel strips 1 and 2 are installed with the welding roll and the end positioning device. By applying a force in the width direction to the steel strips by passing between a plurality of holding rolls that are inclined in the same direction so that a pressing force is exerted in the direction, the edge portions of the steel strips 1 and 2 while allowing the pressing force acts Les - the - welding, then the steel strip 1 and the steel strip 3 that is welded to another welding Russia - and Le, the pressing Russia - inclined Le same direction The steel strips 1, 2 and the steel strip are applied by applying a force in the width direction to the steel strip by passing between a plurality of other holding rolls to be arranged. The laser welding is performed while applying a pressing force to the end face of the edge portion 3. Moreover, in such a method, a steel strip joining method characterized in that a flange roll is arranged upstream of a welding point to be laser welded so that a gap is provided between the steel strips. The invention according to claim 2.
[0006]
In other words, the present invention does not use a single steel plate as the steel plate used for automobile parts, but welds different materials such as plate thickness, strength or properties as steel strips before press forming. This is a method for joining steel strips to obtain a steel plate having the formability or strength required by the automobile parts to be formed in the necessary parts, and after shearing a dissimilar steel plate into a small shape, Instead of the low productivity method of joining the ends, the end portions of the three different steel strips that have been turned back from the coil are continuously welded together, so that the productivity is good and the steel strip An object of the present invention is to provide a method for joining steel strips, which is extremely advantageous in that joining quality is good even when the shape accuracy of the end portion is poor. In addition, as an automobile part manufactured from the steel strip obtained by the present invention, a part having a possibility of being used by joining different kinds of materials such as a part close to a column shape such as a framework structure part of an automobile or a floor in parallel. The method of the present invention can improve the productivity and the yield of these parts.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
As described above, the present invention is a method for joining steel strips in which the edge portions of three strips of steel strips 1, 2, and 3 having different materials, thicknesses, etc. are continuously and advantageously welded. The steel strips 1 and 2 are welded so as to apply a force in the width direction of the steel strip by pressing an inclined pressing roll against the steel strips 1 and 2 so that a pressing force acts between the edges of the steel strip. 2 and the steel strip 3 are welded at different welding positions by using a pressing roll that is inclined in the same manner as described above so that a pressing force acts between the edges, and welding of the three steel strips 1, 2, and 3 This makes it possible to facilitate the bonding and improve the bonding quality as well as the productivity.
[0008]
Hereinafter, the present invention will be described in detail with reference to FIGS.
In this invention, the edge part of three types of steel strips 1, 2, and 3 from which a material, plate | board thickness, etc. differ is joined continuously, First, the steel strips 1 and 2 are put in order, and upper holding roll 4a, 5a and These are passed between the press rolls 4a and 5a and the welding roll 7a having a larger diameter. At this time, the steel strips 1 and 2 are wound around and passed through the large-diameter welding roll 7a side, but the pressing rolls 4a and 5a are welding rolls arranged so as to be orthogonal to the traveling direction of the steel strips 1 and 2. It is arranged so as to be inclined by angles θ 1 and θ 2 with respect to the longitudinal direction of 7a, and pressed against the welding roll 7a so that a force in the width direction is positively applied to the steel strips 1 and 2.
[0009]
As described above, in the present invention, by pressing the pressing rolls 4a and 5a, a force in the width direction is positively applied to the steel strips 1 and 2, and a surface pressure is applied between the edges of the steel strips 1 and 2 to be welded. This is a major feature. When the end portions of the steel strips 1 and 2 are butted and laser-welded, if a gap is generated between the steel strips 1 and 2 to be welded, quality defects such as undercuts are likely to occur after welding. However, when manufacturing a steel strip, in order to ensure the steel strip width accuracy and the shape quality of the steel strip end, the end shearing such as slitting the center of the steel strip or trimming the end is recommended. Although it is finished by processing, since slight irregularities remain at the end of the steel strip, some gaps are generated when these end faces are abutted, and further, when laser welding is performed, due to thermal contraction of the weld zone, Since a force is applied to push the butt surface open, a gap is generated near the upstream of the weld. Therefore, in the present invention, the press rolls 4a and 5a are inclined, a force in the width direction is applied to the steel strips 1 and 2, and a butting force is applied to the end portions of the steel strips 1 and 2 to be welded, thereby forming a gap due to heat shrinkage. The gap between the ends of the steel strips 1 and 2 is remarkably reduced at the welding point by pressing and further applying elastic deformation or plastic deformation of the convex portion at the end of the steel strip to significantly reduce the gap due to the unevenness. Therefore, stable welding quality can be ensured.
[0010]
At this time, in order to give a force in the width direction of the steel strip, a method of applying a force from an end portion of the steel strip such as a side guide roll that is not welded is generally considered, but it is used for an automobile part. For thin steel strips, if these methods are applied with a large force, buckling of the steel strips and rough edges of the ends will occur, so a large force cannot be applied. There was a problem that the gap between the ends of the steel strip could not be reduced. Therefore, in the present invention, a method of inclining and pressing the pressing rolls 4a and 5a to apply the force in the width direction to the steel strips 1 and 2 is adopted, and the pressing force and the inclination angle of the pressing rolls 4a and 5a are adjusted appropriately. By doing so, a sufficient pressing force can be applied to a thin steel strip used for automobile parts without causing buckling of the steel strips 1 and 2 and roughening of the ears of the ends.
[0011]
Further, in the present invention, an end positioning device for the steel strip is installed on one of the end portions on which the steel strips 1 and 2 are not welded, and the press strips 4a and 5a are connected to the end portions of the steel strips 1 and 2, respectively. It is characterized by tilting the pressing rolls 4a and 5a in the same direction. That is, the steel strip 1 and the steel strip 2 are generally joined by applying a pressing force from both sides toward the joint surface 10a. Both of them are configured to exert a pressing force in the same direction, and for this reason, the pressing rolls 4a and 5a are both inclined by angles θ 1 and θ 2 in the same direction. To apply the pressing force from both sides toward the joint surface 10a, it is necessary to adjust the pressing force in a balanced manner from both sides so that the joint surface 10a does not always move to the welding position, but the pressing force from both sides is adjusted. It is difficult to do so, and as in the present invention, the end portion on the end positioning device side of the steel strip 1 is pressed against the steel strip 1 on the end positioning device side by inclining the pressing roll 4a by θ 1. The position in the width direction of the steel strip 1 can be stabilized. Further, the position in the width direction of the steel strip 2 pressed against the weld end of the steel strip 1 is also stabilized by pressing the press roll 5a with an inclination of θ 2, so that the joining surface 10a and the welding position are adjusted so as not to fluctuate. Is made from knowledge that makes it extremely easy. Moreover, welding to the pressing force between the strip ends can be easily controlled by adjusting the pressing force of the roll 5a and the inclination angle theta 2 retainer furthermore welded steel strip 1 large-diameter Wrapping around the roll 7a makes it possible to match the accuracy in the thickness direction of the steel strips 1 and 2 well. If the winding is not performed, a space between the steel strips 1 and 2 and the welding roll 7a is easily formed. This is because there is a high possibility that the butting accuracy of the band 1 and the steel band 2 in the thickness direction is not sufficient.
[0012]
In the present invention, various investigations are made so that the welding surface 10a to be welded is always at the welding position with respect to the position of the fixed laser emitting tube 9a that irradiates the laser beam 8a. This has led to a very different present invention. That is, the idea is that the pressing force is usually applied to the steel strip from both sides to the position so that the position of the joint surface 10a does not fluctuate from the welding position. This is based on the idea of applying a pressing force so that the steel strip moves to one side of one or two. For example, as shown in FIG. 1, edge guides 11a, 11b, and 11c are provided outside the steel strip 1 as an end positioning device, and the steel plate 1 is inclined so that the steel strip 1 moves in the direction of the edge guides 11a, 11b, and 11c. The roll 4a is provided on the upper part of the welding roll 7a. The pressing roll 4a gives a force for pressing the welding roll 7a with a cylinder or the like, for example, and moves the steel strip 1 in the direction of the arrow while restraining the steel strip 1. Since roll 4a pressing this time is inclined by an angle theta 1, the steel strip 1 is intended to be pressed against the edge guide 11a, to 11b. Incidentally, roll 4a retainer such that the edge of the steel strip 1 is not damaged is to be able to adjust the pressing force and the angle theta 1. Moreover, when the steel strip 1 is restrained by the edge guides 11a and 11b, the edge guides 11a and 11b are adjusted in the width direction of the steel strip 1 so that the position of the joint surface 10a to be welded becomes the welding position. Is possible.
[0013]
In this way, the position of the steel strip 1 is adjusted in the width direction. Similarly, the steel strip 2 is moved in a state of being restrained by the press roll 5a inclined by the angle θ 2 , and θ 2 and the press roll 5a are moved. By appropriately adjusting the pressing force of the steel strip 2, the joining surface 10a of the steel strip 2 exerts an appropriate pressing force on the joining surface 10a of the steel strip 1, and the surface pressure of the edge surfaces of the steel strips 1 and 2 is raised. In other words, welding is performed in a state in which the gap is crushed, in other words, by performing a pinch-type butt, the welding quality is improved, which is extremely advantageous. In this way, the welding position of the steel strips 1 and 2 can be accurately adjusted only by considering the pressing force in one direction, and the surface pressure is set between the edges of the steel strips 1 and 2 for welding. The welding quality is improved. Thus, after adjusting the joining surface 10a of the steel strips 1 and 2 to a welding position, the laser beams 8a are irradiated and welded from the laser emitting tube 9a, and the steel strips 1 and 2 are joined.
[0014]
After welding the steel strip 1 and the steel strip 2 in this way, the welded steel strips 1 and 2 and the steel strip 3 are separated from another welding roll 7b and another plurality of pressing rolls 4b and 5b that are inclined. , 6 is applied to the steel strip to apply a force in the width direction so that the pressing force is applied to the edge ends of the steel strips 1 and 2 and the steel strip 3, and laser welding is performed.
That is, in the same manner as welding the steel strip 1 and the steel strip 2, the steel strip 3 is welded to the welded steel strips 1 and 2, and the pressing roll 4b inclined by the angles θ 3 and θ 4 , 5b is provided on the upper portion of the welding roll 7b, and the pressing rolls 4b and 5b apply a force to press the welding roll 7b to move the steel strips 1 and 2 in the direction of the edge guides 11b and 11c. Similarly, the joining surface 10b of the steel strip 3 is moved by moving the steel strip 3 in a state of being restrained by the press roll 6 inclined by an angle θ 5 and adjusting the press force of θ 5 and the press roll 6 appropriately. Is to apply an appropriate pressing force to the joint surface 10b of the steel strips 1 and 2, and establishes a surface pressure on the edge surfaces of the steel strips 1 and 2 and the steel strip 3, and welds in a state where the gap is crushed, The welding quality is improved, which is extremely advantageous.
In addition, as shown in FIGS. 3 and 4, four pressing rolls 4, 5, and 6 may be used for each of the steel strips 1, 2, and 3, and various arrangement forms may be considered, but there is no particular concern.
[0015]
Further, as shown in FIG. 5, the welding roll 7a is provided with a groove 12a at a position corresponding to the welding position, so that the welding roll 7a is prevented from being damaged due to the heat effect during welding. FIG. 5 shows the joining of the steel strips 1, 2 and 3 having different thicknesses. However, since the diameter of the welding roll 7a is the same, the steel strips 1 and 2 are formed on the lower surface of the steel strips 1 and 2. We are trying to weld them together. In FIG. 6, the upper surfaces of the steel strips 1 and 2 are welded together, and in FIG. 7, the thin steel strip 2 is welded to the center of the thickness of the thick steel strip 1. Can be easily achieved by using a welding roll 7a having different left and right diameters across the groove 12a of the welding roll 7. Further, the right and left diameters of the welding roll 7a may be varied so that the welding roll 7a can be freely expanded and contracted, and the means is not particularly limited. Although the groove 12a has been described with the welding roll 7a as an example with reference to FIGS. 5 to 7, the groove 12b (not shown) is provided at a position corresponding to the welding position in the welding roll 7b, and the welding roll 7b. As for the welding roll 7a, the form thereof is the same.
[0016]
Furthermore, in this invention, as shown in FIG. 8, the flange roll 14a is arrange | positioned in the upstream of the welding point 13a, and it is trying to provide a clearance gap between the steel strips 1 and 2. As shown in FIG. In the present invention, the steel strips 1 and 2 are passed through the same plane and conveyed to the welding point 13a. For this reason, the joining surface 10a of the steel strips 1 and 2 is rubbed or the steel strip 1 is rubbed. Since the steel strip 2 may overlap, it is more preferable to provide the flange roll 14a between the steel strips 1 and 2 in order to prevent this. In addition, it is more preferable to provide the flange roll 14b on the upstream side of the welding point 13b as well.
[0017]
Incidentally, the pressing roll 4, 5, 6 used in the present invention are those which each angle theta 1 through? 5 inclination angle theta 1 through? 5 are both 2 ° to 25 ° is preferred, also, the pressing roll 4 The pressing force of 5 and 6 is preferably 350N to 20000N. The reason is that when the angles θ 1 to θ 5 are less than 2 ° or the pressing force is less than 350 N, the pressing force in the width direction of the steel strips 1, 2, and 3 is insufficient and the welding quality is not preferable, and the angle θ 1 to This is because if θ 5 exceeds 25 ° or the pressing force exceeds 20000 N, the pressing force becomes too large, and buckling of the steel strips 1, 2, and 3 may occur. However, the above-described ranges of the angle and the pressing force are merely preferable ranges, and do not stick to these ranges unless buckling occurs.
In addition, the three different steel strips of the present invention are those in which the materials and thicknesses of adjacent steel strips are different, and the steel strips at both ends are the same and the central steel strips are different. It is what.
[0018]
[Example 1]
A steel strip 1 having a thickness of 0.7 mm and a width of 250 mm and a steel strip 2 having a thickness of 1.4 mm and a width of 690 mm, and a steel having a thickness of 0.7 mm and a width of 250 mm of chemical components shown in Table 1 manufactured according to a conventional method. Prepare strip 3 and join steel strip 1 and steel strip 2 at a speed of 1.7 m / min with a 2 kw laser welder, and then weld steel strip 3 to welded steel strips 1 and 2 with a 2 kw laser. Joining was performed at a speed of 1.7 m / min with a welding machine.
Hereinafter, the components of the steel strip are shown in Table 1, and the joining conditions and welding results are shown in Tables 2 and 3.
[0019]
[Table 1]
Figure 0004047470
[0020]
[Table 2]
Figure 0004047470
[0021]
[Table 3]
Figure 0004047470
As is apparent from the above table, according to the present invention, there is no occurrence of buckling and no occurrence of undercut, and extremely good weld quality can be obtained.
[0022]
[Example 2]
In order to form the steel strip 1, the steel strip 2, and the steel strip 3 shown in Example 1 into automobile parts (center pillars), each was cut into 1000 mm. In this case, the present invention cuts after joining the steel strips 1, 2, and 3, and in the comparative example, the steel strips were joined after cutting the steel strips 1, 2, and 3. Table 4 shows the required time at that time.
[0023]
[Table 4]
Figure 0004047470
As shown in Table 4, it can be seen that according to the present invention, productivity is dramatically improved as compared with the cut plate joining method shown in the comparative example.
[0024]
【The invention's effect】
As apparent from the above description, according to the present invention, when manufacturing automobile parts and the like by the tailored blank method, it is possible to join steel strips with good welding quality and good productivity, and the effect is extremely large. Is.
[Brief description of the drawings]
FIG. 1 is an explanatory plan view of a method of the present invention.
2 is an explanatory side view of the method of the present invention shown in FIG.
FIG. 3 is an explanatory plan view of the method of the present invention in which the number of pressing rolls is increased.
4 is an explanatory side view of the method of the present invention shown in FIG. 3. FIG.
FIG. 5 is an enlarged explanatory view showing the vicinity of welding in the method of the present invention.
FIG. 6 is an enlarged explanatory view showing the vicinity of welding in the method of the present invention.
FIG. 7 is an enlarged explanatory view showing the vicinity of welding in the method of the present invention.
FIG. 8 is an explanatory view showing a state in which a flange roll is provided on the upstream side of the welding point in the method of the present invention.
[Explanation of symbols]
1 Steel strip 1
2 Steel strip 2
3 Steel strip 3
4 Pressing roll 5 Pressing roll 6 Pressing roll 7 Welding roll 8 Laser beam 9 Laser launch tube
10 Joint surface
11 Edge guide
12 groove
13 Weld point
14 Flange roll

Claims (2)

３条の異なる鋼帯１、２、３のエッジ部を連続的に溶接するに際し、鋼帯１、２の溶接を行わない側の端部の一方に、鋼帯の端部位置決め装置を設置し、鋼帯１、２を、溶接ロ−ルと、前記端部位置決め装置を設置してある方向に押付力が働くように同一方向に傾斜して配置する複数の押さえロ−ルとの間を通過させることにより鋼帯に幅方向の力を加えて鋼帯１、２のエッジ部端面に押付力が働くようにしながらレ−ザ−溶接し、次いで、溶接された鋼帯１、２と鋼帯３を、別の溶接ロ−ルと、前記押さえロ−ルと同一方向に傾斜して配置する別の複数の押さえロ−ルとの間を通過させることにより鋼帯に幅方向の力を加えて鋼帯１、２と鋼帯３のエッジ部端面に押付力が働くようにしながらレ−ザ−溶接することを特徴とする鋼帯の接合方法。When continuously welding the edges of steel strips 1, 2, and 3 with three different strips, an end positioning device for the steel strip is installed on one of the ends on the side where the steel strips 1 and 2 are not welded. The steel strips 1 and 2 are disposed between the welding rolls and a plurality of pressing rolls that are inclined in the same direction so that the pressing force acts in the direction in which the end positioning device is installed. Laser welding is performed by applying a force in the width direction to the steel strips by passing the steel strips 1 and 2 so that a pressing force acts on the end faces of the steel strips 1 and 2, and then the welded steel strips 1 and 2 and the steel strips. By passing the band 3 between another welding roll and a plurality of other pressing rolls arranged in the same direction as the pressing roll, a force in the width direction is applied to the steel band. In addition, the steel strips 1 and 2 and the steel strip 3 are welded by laser welding while applying a pressing force to the end faces of the steel strip 3 Law. レ−ザ−溶接する溶接点の上流側にフランジロ−ルを配置して鋼帯鋼帯の間に隙間を設けるようにしてあることを特徴とする請求項１記載の鋼帯の接合方法。  2. The method of joining steel strips according to claim 1, wherein a flange roll is disposed upstream of a welding point to be laser welded so that a gap is provided between the steel strip steel strips.
JP33996998A 1998-11-30 1998-11-30 Steel strip joining method Expired - Lifetime JP4047470B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP33996998A JP4047470B2 (en) 1998-11-30 1998-11-30 Steel strip joining method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP33996998A JP4047470B2 (en) 1998-11-30 1998-11-30 Steel strip joining method

Publications (2)

Publication Number Publication Date
JP2000158165A JP2000158165A (en) 2000-06-13
JP4047470B2 true JP4047470B2 (en) 2008-02-13

Family

ID=18332492

Family Applications (1)

Application Number Title Priority Date Filing Date
JP33996998A Expired - Lifetime JP4047470B2 (en) 1998-11-30 1998-11-30 Steel strip joining method

Country Status (1)

Country Link
JP (1) JP4047470B2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10350670B3 (en) * 2003-10-30 2005-02-03 Thyssenkrupp Stahl Ag Metal sheet for producing vehicle components consist of at least two cutouts, with straight joint line
JP6162397B2 (en) * 2012-12-20 2017-07-12 株式会社エフテック Differential thickness material and cylindrical member using the same

Also Published As

Publication number Publication date
JP2000158165A (en) 2000-06-13

Similar Documents

Publication Publication Date Title
US4840303A (en) Method and apparatus for cutting and welding steel strips
US4854493A (en) Method and apparatus for cutting welding steel strips
KR20140044330A (en) Device and method for producing a customized sheet metal strip or metal profile
JP3813182B2 (en) Method for manufacturing a welded steel plate intermediate product
US5447588A (en) Method for ultrasonically splicing web
JP4593458B2 (en) Welding method of lap joint
JP4047470B2 (en) Steel strip joining method
JP4786401B2 (en) Method for manufacturing butt-welded metal sheet
JP6761663B2 (en) How to process a plate-shaped work
JP4687924B2 (en) Manufacturing method of ring member
JP2002224840A (en) Method for welding open pipe
JP4505071B2 (en) Steel strip joining method
JP3971525B2 (en) Steel strip joining method
JP2012148332A (en) Method of manufacturing tailored blank material
JP4047469B2 (en) Steel strip joining method
JP4505070B2 (en) Steel strip joining method
JP2001269785A (en) Coil for tailored blank material, method and device for manufacturing the same
JP2000000612A (en) Method for continuously welding strip steel sheet in longitudinal direction and continuous welding equipment
JP2000024794A (en) Method and equipment for continuous welding of strip steel plate in longitudinal direction
JP4378635B2 (en) Lap laser welding method
JP4264186B2 (en) Method and apparatus for butt joining steel plates or steel strips
JP2719979B2 (en) Welding method
JP7205395B2 (en) welding machine
KR100544792B1 (en) Method for calmping steel sheet in laser welding
KR100393891B1 (en) Welding method of Tailored Welded Blank using Electrode Roller System

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20040901

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20060908

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20060912

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20061109

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20070601

A521 Written amendment

Free format text: JAPANESE INTERMEDIATE CODE: A523

Effective date: 20070726

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20071116

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20071122

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20101130

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20101130

Year of fee payment: 3

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111130

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20111130

Year of fee payment: 4

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121130

Year of fee payment: 5

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20121130

Year of fee payment: 5

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131130

Year of fee payment: 6

S531 Written request for registration of change of domicile

Free format text: JAPANESE INTERMEDIATE CODE: R313531

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131130

Year of fee payment: 6

S533 Written request for registration of change of name

Free format text: JAPANESE INTERMEDIATE CODE: R313533

FPAY Renewal fee payment (event date is renewal date of database)

Free format text: PAYMENT UNTIL: 20131130

Year of fee payment: 6

R350 Written notification of registration of transfer

Free format text: JAPANESE INTERMEDIATE CODE: R350

EXPY Cancellation because of completion of term