JP3660793B2 - Method for increasing the thickness of metal strip - Google Patents

Description

【００３０】
【数２】

【００３１】
（２）増肉終了時に発生するたわみ
図４（ａ）に示すように、加熱装置４が増肉終了位置Ｅにあるものとし、各部寸法を図４に示すように定めておく。そして、条材１が増肉終了位置にある加熱部５の最軟部で切り離され、その両側の条材部分１ａ、１ｂがそれぞれ片持ち梁を形成するものとみなす。
【００３２】
▲１▼ 後側条材部分１ａ
固定側ガイドローラ８で支持された後側条材部分１ａは、図４（ｂ）に示すように片持ち梁となる。この時の片持ち梁の自由端の下方への変位量δ_2Eを計算するに当たっては、計算を簡略化するため、増肉しない領域には自重による一定の分布荷重ｑが作用し、増肉を行った厚肉部１ｃには、その中央に厚肉部１ｃ全体の重量Ｐ_Z が集中荷重として作用しているのもと仮定する。この集中荷重Ｐ_Z は、増肉率をβとすると、
Ｐ_Z ＝ｑＬ_Z （１＋β）
で計算できる。
【００３３】
まず、図４（ｃ）に示すように、片持ち梁（条材部分１ａ）に分布荷重ｑのみが作用するものとして（厚肉部の重量はないものとして）、自由端の変位量δ_2qを計算する。増肉開始位置であるＳ点の変位量δ₂ は、図３（ｂ）に示す片持ち梁の自由端の変位量δ_2Sに等しい。従って、Ｓ点の変位量δ₂ は、数式３のようになる。
【００３４】
【数３】

【００３５】
次に、Ｓ点における傾斜角θ₂ は数式４となる。
【００３６】
【数４】

【００３７】
従って、片持ち梁先端のＳ点からの下方への変位量δ₂ ′は、数式５のようになり、自由端の変位量δ_2qは数式６で計算できる。
【００３８】
【数５】

【００３９】
【数６】

【００４０】
次に、図４（ｄ）に示すように、片持ち梁に集中荷重Ｐ_Z のみが作用するものとして、自由端の変位量δ_2Zを計算する。まず、Ｓ点の変位量δ_2Z′は、数式７となる。また、その位置での変位角θ_2Zは数式８となるので、片持ち梁の自由端のＳ点からの下方への変位量δ_2Z″は、数式９のようになる。従って自由端の変位量δ_2Zは数式１０により計算できる。
【００４１】
【数７】

【００４２】
【数８】

【００４３】
【数９】

【００４４】
【数１０】

【００４５】
図４（ｂ）に示すように、片持ち梁（条材部分１ａ）に分布荷重ｑと集中荷重Ｐ_Z とが作用した時の自由端の変位量δ_2Eは、分布荷重ｑのみが作用した時の自由端の変位量δ_2q［図４（ｃ）参照］と、集中荷重Ｐ_Z のみが作用した時の自由端の変位量δ_2Z［図４（ｄ）参照］を足したものであるので、結局、増肉加工終了時の後側条材部分１ａの自由端に生じる下方への変位量δ_2Eは、数式１１で計算できる。
【００４６】
【数１１】

【００４７】
▲２▼ 前側条材部分１ｂ
一方、移動側ガイドローラ９で支持された前側条材部分１ｂは、増肉終了時にも、図４（ｅ）に示すような寸法の片持ち梁となり、これは、図３（ｃ）に示す増肉開始時の片持ち梁と同一である。従って、増肉終了時の変位量δ_3Eは、増肉開始時の変位量δ_3Sと等しく、数式１２で示すようになる。
【００４８】
【数１２】

【００４９】
以上のようにして、増肉開始時及び増肉終了時の各条材部分１ａ、１ｂの自由端の変位量を計算し、それに基づいて矯正用の変位或いは荷重を求めることができる。
【００５０】
以上の説明は、図７に示すように、条材１の増肉部分をフリーとした状態で増肉加工を行う場合を示したが、本発明はこの場合に限定されず、例えば、図９に示すように、条材１内の、増肉加工によって形成される厚肉部１ｅの内側に位置するように熱処理用ダイス等の中子１２を挿入した状態で増肉加工を行う場合にも適用可能である。ここで用いられる中子１２は、増肉加工によって形成する厚肉部１ｃの長さ以上の長さを有するもので、その両端に条材１の内面に接触させることで中子１２の外面と条材１の内面との間隔を一定に保持するための突起１２ａを備えている。この中子１２には連結棒１３が接続されているが、この連結棒１３は単に中子１２の長手方向の位置決めのために設けられたもので、中子１２の重量を支えるものではない。従って、中子１２の重量は条材１によって保持されており、換言すれば、中子１２の重量は条材１に荷重として作用し、その重量は中子１２の両端の突起１２ａによって集中荷重として作用する。なお、中子１２を設けた点以外の構成は、図７に示す増肉加工装置と同様である。
【００５１】
図９に示すように、条材１に中子１２を挿入した状態で増肉加工を行う場合には、増肉を開始すると、増肉で形成される厚肉部１ｃの内面が中子１２の外周面に押し付けられ、一体化しながら増肉が進行する。このように、厚肉部が中子１２に密着し、一体化しながら増肉が進む間は、条材１と中子１２とが１本の両端支持梁のように作用し、加熱部５に段差はあまり生じない。しかしながら、増肉開始から、厚肉部が中子１２に密着するまでの間は、加熱部５の両側に位置する条材部分１ａ、１ｂは中子１２で拘束されていないので、それぞれ自由に動くことができ、加熱部５の最軟部で切り離された片持ち梁のような挙動を示す。従って、各条材部分１ａ、１ｂの自由端（加熱部５）の下方への変位量が異なり、曲がり発生の原因となる。
【００５２】
そこで、この場合に対して本発明を適用することができる。すなわち、増肉加工の開始時において、加熱部５の両側の条材部分１ａ、１ｂをそれぞれ、加熱部５の最軟部で切り離され、加熱部側を自由端とする片持ち梁とみなし、それぞれの自由端の下方への変位量を計算で求める。この時の計算には当然、中子１２による集中荷重を考慮する。そして、計算で求めた変位量を矯正することができるように、矯正用の変位或いは荷重を求め、それを、第一及び第二曲がり矯正手段２０、３０によって、条材部分１ａ、１ｂにそれぞれ加えた状態で増肉加工を行う。これにより、増肉開始から、厚肉部が中子と一体化するまでの間に加熱部５に生じる恐れのある段差の発生を防止し、曲がり発生を防止しながら、増肉加工を行うことができる。なお、増肉開始時に各条材部分１ａ、１ｂに加えた矯正用の変位或いは荷重は、厚肉部が中子と一体化した後もそのまま、加えておくことが好ましい。
【００５３】
次に、中子１２を使用した場合の、増肉開始時の各条材部分１ａ、１ｂの自由端の変位量の計算方法の１例を説明する。図５（ａ）に示すように、加熱装置４が増肉開始位置Ｓにあるものとし、各部寸法を図５に示すように定めておく。この場合にも、条材１が増肉開始位置にある加熱部５の最軟部で切り離され、その両側の条材部分１ａ、１ｂがそれぞれ片持ち梁を形成するものとみなす。
【００５４】
▲１▼ 後側条材部分１ａ
まず、図５（ｃ）に示すように、固定側ガイドローラ８で保持された後側条材部分１ａを片持ち梁とみなし、且つそれに対して分布荷重ｑのみが作用するものとして（中子１２による集中荷重は作用していないものとして）、自由端の変位量δ_2qを計算する。この変位量δ_2qは、数式１３で求めることができる。
【００５５】
【数１３】

【００５６】
次に、図５（ｄ）に示すように、片持ち梁（条材部分１ａ）の自由端に中子１２による集中荷重Ｐ₁ のみが作用するものとして、自由端の変位量δ₂₁を計算する。なお、中子１２による集中荷重は、条材部分１ａの自由端（加熱部５）から少し離れた位置に作用しているが、そのずれは小さいので省略する。自由端の変位量δ₂₁は数式１４により計算できる。
【００５７】
【数１４】

【００５８】
図５（ｂ）に示すように、片持ち梁に分布荷重ｑと集中荷重Ｐ₁ とが作用した時の自由端の変位量δ_21S は、分布荷重ｑのみが作用した時の変位量δ_2q［図５（ｃ）参照］と、集中荷重のみが作用した時の変位量δ₂₁［図５（ｄ）参照］を足したものであるので、結局、後側条材部分１ａの自由端に生じる下方への変位量δ_21S は、数式１５で計算できる。
【００５９】
【数１５】

【００６０】
▲２▼ 前側条材部分１ｂ
図５（ｆ）に示すように、移動側ガイドローラ９で保持された前側条材部分１ｂを片持ち梁とみなす。そして先ず、それに対して分布荷重ｑのみが作用するものとして（中子１２による集中荷重は作用していないものとして）、自由端の変位量δ_3qを計算する。この変位量δ_3qは、数式１６で求めることができる。
【００６１】
【数１６】

【００６２】
次に、図５（ｇ）に示すように、片持ち梁（条材部分１ｂ）の自由端から、増肉長さに相当する距離Ｌ_N だけ離れた位置（増肉終了位置即ちＥ点）に中子１２による集中荷重Ｐ₂ のみが作用するものとして、自由端の変位量δ₃₂を計算する。なお、中子１２による集中荷重は、増肉終了位置Ｅから少し離れた位置に作用しているが、そのずれは小さいので省略する。
【００６３】
まず、Ｅ点の変位量δ₃₂′は、数式１７となる。またその位置での変位角θ₃ は数式１８となるので、片持ち梁の自由端のＥ点からの下方への変位量δ₃₂″は、数式１９のようになる。従って、先端の変位量δ_3Zは数式２０により計算できる。
【００６４】
【数１７】

【００６５】
【数１８】

【００６６】
【数１９】

【００６７】
【数２０】

【００６８】
図５（ｅ）に示すように、片持ち梁に分布荷重ｑと集中荷重Ｐ₂ とが作用した時の自由端の変位量δ_32S は、分布荷重ｑのみが作用した時の変位量δ_3q［図５（ｆ）参照］と、集中荷重Ｐ₂ のみが作用した時の変位量δ₃₂［図５（ｇ）参照］を足したものであるので、結局、前側条材部分１ｂの自由端に生じる下方への変位量δ_32S は、数式２１で計算できる。
【００６９】
【数２１】

【００７０】
以上のようにして、中子１２を使用する場合における増肉開始時の各条材部分１ａ、１ｂの自由端（加熱部）の変位量を計算でき、それに基づいて矯正用の変位或いは荷重を求めることができる。
【００７１】
なお、以上の説明は、本発明方法を、図７或いは図９に示す構成の装置を用いた増肉加工について適用した場合についてのものであるが、増肉加工に使用する装置はこれに限らず、適宜変更可能である。例えば、加熱装置４と同期して移動する移動側ガイドローラ９を用いる代わりに、定位置に配置したガイドローラを用いても良い。その場合には、増肉の進行につれて加熱部５とガイドローラとの間隔が変化するので、前側条材部分１ｂの自由端の変位量δ₃ の計算や矯正量の設定に当たって、後側条材部分１ａと同様に間隔の変化を考慮すればよい。また、図７、図９に示す装置では、加熱部５の両側の条材部分１ａ、１ｂをそれぞれ、間隔を開けて配置した２組のガイドローラ８、９で保持しているが、このガイドローラの本数を増加させるとか、クランプ等の他の機構を用いる等の変更を行っても良い。その場合には、片持ち梁の自由端の変位量の計算に当たって、その片持ち梁を保持している機構の特性を考慮すれば良い。
【００７２】
更に、上記した説明では、増肉加工に供する条材は真直なものであることを前提としている。ところで、増肉加工に供する条材には、増肉加工に供する前に既に曲がりを有しているものがある。このように冷間の状態で曲がりを有している条材を、図７に示す増肉加工装置にセットして増肉加工を行う場合、条材の増肉加工すべき部分の両側の条材部分１ａ、１ｂをそれぞれ、間隔を開けて配置された複数のガイドローラ８、９で所定の加工基準軸心に拘束すると、条材のガイドローラ８、９によって拘束された部分は加工基準軸心上に保持されるが、その他の部分は必ずしも加工基準軸心上に位置するとは限らず、特に、加熱部は加工基準軸心から変位することが多い。この場合に対しても本発明を適用することが可能である。すなわち、ガイドローラ８、９でそれぞれ保持した条材部分を、加熱部で切り離した片持ち梁とみなし、それぞれの自由端の変位量を計算するに当たっては条材が冷間時に持っていた曲がりを考慮し、求めた変位量を矯正するように、各条材部分に加える矯正用の変位或いは荷重を求め、その矯正用の変位或いは荷重を各条材部分に加えた状態で増肉加工することにより、増肉加工中の加熱部に生じる恐れのある段差を抑制して、曲がりの発生を防止できる。
【００７３】
【実施例】
［実施例１］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子なし）
▲２▼ 増肉条件
供試条材：３００ｍｍ角×１２ｍｍ厚さ×１５０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝１１５０ｍｍ、３ヶ所増肉
増肉率β＝１００％
【００７４】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して１１ｍｍ下向きに曲がっていた。
【００７５】
▲４▼ 変位量の計算及び矯正用変位の計算
加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時及び終了時について計算し、表１に示す結果を得た。また、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表１に示す結果を得た。なお、表１及び後述する表２〜表６において、「固定側」は、加熱部５の後ろに位置する後側条材部分１ａに関するものであり、「移動側」は、加熱部５の前に位置する前側条材部分１ｂに関するものである。また、表中の単位はｍｍである。
【００７６】
【表１】

【００７７】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量と、増肉終了時の押し上げ量の平均値を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝（０．０２１５＋０．３７４）／２≒０．２（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【００７８】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．２ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±４ｍｍであり、矯正しない場合に比べて、曲がりを大幅に減少させることができた。
【００７９】
［実施例２］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子なし）
▲２▼ 増肉条件
供試条材：２５０ｍｍ角×９ｍｍ厚さ×１５０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝８５０ｍｍ、３ヶ所増肉
増肉率β＝１００％
【００８０】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して１２ｍｍ下向きに曲がっていた。
【００８１】
▲４▼ 変位量の計算及び矯正用変位の計算
増肉加工時の加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時及び終了時について計算し、表２に示す結果を得た。また、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表２に示す結果を得た。
【００８２】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量と、増肉終了時の押し上げ量の平均値を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝（０．０３０７＋０．３６５）／２≒０．２（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【００８３】
【表２】

【００８４】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．２ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±４ｍｍであり、矯正なしに比べて曲がりを大幅に減少させることができた。
【００８５】
［実施例３］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子なし）
▲２▼ 増肉条件
供試条材：１７５ｍｍ角×９ｍｍ厚さ×１２０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝５５０ｍｍ、３ヶ所増肉
増肉率β＝６６．７％
【００８６】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して１０．５ｍｍ下向きに曲がっていた。
【００８７】
▲４▼ 変位量の計算及び矯正用変位の計算
増肉加工時の加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時及び終了時について計算し、表３に示す結果を得た。また、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表３に示す結果を得た。
【００８８】
【表３】

【００８９】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量と、増肉終了時の押し上げ量の平均値を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝（０．０６４６＋０．４１９）／２≒０．２４（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【００９０】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．２４ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±３ｍｍであり、矯正なしに比べて曲がりを大幅に減少させることができた。
【００９１】
［実施例４］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子あり）
中子：重量Ｗ＝５００ｋｇ、長さＬ＝１４６０ｍｍ
▲２▼ 増肉条件
供試条材：３００ｍｍ角×１２ｍｍ厚さ×１５０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝１１５０ｍｍ、３ヶ所増肉
増肉率β＝１００％
【００９２】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して７．５ｍｍ下向きに曲がっていた。
【００９３】
▲４▼ 変位量の計算及び矯正用変位の計算
増肉開始時の加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時について計算し、表４に示す結果を得た。また、増肉終了時には条材が中子と一体となった両持ち梁とみなして、加熱部の変位量を計算し表４の結果を得た。更に、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表４に示す結果を得た。
【００９４】
【表４】

【００９５】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝０．１８２≒０．１８（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【００９６】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．１８ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±３ｍｍであり、矯正なしに比べて曲がりを大幅に減少させることができた。
【００９７】
［実施例５］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子あり）
中子：重量Ｗ＝４００ｋｇ、長さＬ＝１３５０ｍｍ
▲２▼ 増肉条件
供試条材：２５０ｍｍ角×９ｍｍ厚さ×１５０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝８５０ｍｍ、３ヶ所増肉
増肉率β＝１００％
【００９８】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して８．０ｍｍ下向きに曲がっていた。
【００９９】
▲４▼ 変位量の計算及び矯正用変位の計算
増肉開始時の加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時について計算し、表５に示す結果を得た。また、増肉終了時には条材が中子と一体となった両持ち梁とみなして、加熱部の変位量を計算し表５の結果を得た。更に、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表５に示す結果を得た。
【０１００】
【表５】

【０１０１】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝０．３２４≒０．３２（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【０１０２】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．３２ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±３．５ｍｍであり、矯正なしに比べて曲がりを大幅に減少させることができた。
【０１０３】
［実施例６］
▲１▼ 増肉加工装置
図６（ａ）（ｂ）に示す寸法の増肉加工装置（中子あり）
中子：重量Ｗ＝４００ｋｇ、長さＬ＝１３５０ｍｍ
▲２▼ 増肉条件
供試条材：１７５ｍｍ角×９ｍｍ厚さ×１２０００ｍｍ長さの角形鋼管
増肉長さＬ_Z ＝５５０ｍｍ、３ヶ所増肉
増肉率β＝６６．７％
【０１０４】
▲３▼ 矯正なしでの増肉
加圧ローラ２１、３１による押し上げ量を０に設定し、増肉加工を行ったところ、得られた増肉条材は全長に対して２４ｍｍ下向きに曲がっていた。
【０１０５】
▲４▼ 変位量の計算及び矯正用変位の計算
増肉開始時の加熱部５の両側の条材部分１ａ、１ｂをそれぞれ片持ち梁とみなして、自由端の変位量を増肉開始時について計算し、表６に示す結果を得た。また、増肉終了時には条材が中子と一体となった両持ち梁とみなして、加熱部の変位量を計算し表６の結果を得た。更に、増肉開始時及び終了時についてそれぞれ、計算で求めた変位量を０に矯正するための加圧ローラ２１、３１による押し上げ量（矯正用変位）Δｙを計算し、表６に示す結果を得た。
【０１０６】
【表６】

【０１０７】
▲５▼ 押し上げ量の設定
固定側（後側条材部分１ａ）については、増肉開始時の押し上げ量を矯正用の押し上げ量Δｙ_m と設定した。すなわち、
Δｙ_m ＝０．６２４≒０．６２（ｍｍ）
と設定した。一方、移動側（前側条材部分１ｂ）は変位量が微小であるので、特に矯正は必要ないと判断し、押し上げ量は０に設定した。
【０１０８】
▲６▼ 増肉加工及び結果
増肉加工の開始前に、第一曲がり矯正手段の加圧ローラ２１で後側条材部分１ａを設定した押し上げ量Δｙ_m ＝０．６２ｍｍだけ押し上げ、その状態に保持して増肉加工を行った。増肉加工後、増肉条材の全長に対する曲がりを測定したところ、±４．５ｍｍであり、矯正なしに比べて曲がりを大幅に減少させることができた。
【０１０９】
【発明の効果】
以上のように、本発明方法は、金属条材の加熱部の最軟部の両側に位置する前側条材部分と後側条材部分をそれぞれ、前記最軟部で切り離され、その最軟部側を自由端とする２本の片持ち梁とみなし、それぞれの片持ち梁に作用する自重によって、或いは中子を用いる場合には片持ち梁に作用する自重及び中子による荷重によって、各片持ち梁の自由端に生じる加工基準軸心からの変位量を計算すると共に、その変位量に基づいて、片持ち梁の自由端の変位を修正するように前記片持ち梁に加える矯正用変位、荷重若しくは曲げモーメントを求め、２本の片持ち梁について求めた二つの矯正用変位、荷重若しくは曲げモーメントをそれぞれ、対応する前側条材部分及び後側条材部分に加えた状態で増肉加工を行う構成としたことにより、増肉加工時に実際に条材に生じるたわみ変形にきわめて近似した計算によってたわみ矯正を行うことができ、従って、増肉加工中における加熱部を加工基準軸心の近傍に矯正して、加熱部に生じる恐れのある段差を抑制でき、曲がりの発生を防止しながら増肉加工を行うことができる。従って、本発明方法は、曲がりのほとんどない増肉加工条材を得ることができるという効果を有している。
【図面の簡単な説明】
【図１】本発明方法の原理を説明するもので、（ａ）は増肉加工中の状態を示す概略側面図、（ｂ）は片持ち梁とみなした条材部分１ａ、１ｂに生じる変位を示す概略側面図、（ｃ）はその変位を矯正した状態を示す概略側面図
【図２】図１（ｂ）に示す条材部分１ａ、１ｂの自由端の変位量と加熱部の位置との関係を示すグラフ
【図３】増肉開始時の変位量の計算条件を説明するもので、（ａ）は増肉開始時の状態を示す概略側面図、（ｂ）は片持ち梁とみなした条材部分１ａに作用する自重及び変位を示す概略側面図、（ｃ）は片持ち梁とみなした条材部分１ｂに作用する自重及び変位を示す概略側面図
【図４】増肉終了時の変位量の計算条件を説明するもので、（ａ）は増肉終了時の状態を示す概略側面図、（ｂ）（ｃ）（ｄ）は片持ち梁とみなした条材部分１ａに作用する自重、荷重、及び変位を示す概略側面図、（ｃ）は片持ち梁とみなした条材部分１ｂに作用する自重及び変位を示す概略側面図
【図５】増肉開始時の変位量の計算条件を説明するもので、（ａ）は増肉開始時の状態を示す概略側面図、（ｂ）（ｃ）（ｄ）は片持ち梁とみなした条材部分１ａに作用する自重、荷重、及び変位を示す概略側面図、（ｅ）（ｆ）（ｇ）は片持ち梁とみなした条材部分１ｂに作用する自重、荷重、及び変位を示す概略側面図
【図６】実施例１〜６に用いる増肉加工装置を示すもので、（ａ）は増肉開始時の概略側面図、（ｂ）は増肉終了時の概略側面図
【図７】本発明方法に使用する増肉加工装置の１例を示す概略垂直断面図
【図８】図７の矢印Ａ−Ａ方向の概略断面図
【図９】本発明方法に使用する増肉加工装置の他の例を示す概略垂直断面図
【符号の説明】
１ 条材
１ａ 後側条材部分
１ｂ 前側条材部分
１ｃ 厚肉部
２ 固定保持具
３ 可動保持具
３Ａ 圧縮装置
４ 加熱装置
５ 加熱部
６ 冷却媒体
７ 移動台
８ 固定側ガイドローラ
９ 移動側ガイドローラ
１０ 移動台
１２ 中子（熱処理用ダイス）
２０ 第一曲がり矯正手段
２１ 加圧ローラ
２３ 加圧シリンダ
３０ 第二曲がり矯正手段
３１ 加圧ローラ
３３ 加圧シリンダ[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a metal strip that increases the thickness of at least one portion in the longitudinal direction of a metal strip (such as H-shaped, I-shaped, round pipe, square pipe, round bar, square bar, plate, etc.) such as steel having a constant cross section. The present invention relates to a method for increasing the thickness of wood.
[0002]
[Prior art]
Conventionally, it is known that a thick portion having a high strength is formed by performing a thickening process on a partial region in the longitudinal direction of a metal strip such as steel (hereinafter simply referred to as strip). An example is described in JP-A-8-66736. In the thickening method described in this publication, the axially compressive force is applied to the strip material to be thickened, and the narrow region in the longitudinal direction of the strip material is locally localized by an annular induction heating coil. Heating to a temperature at which plastic deformation is easy, causing the heated portion, that is, the heated portion to increase in thickness due to compressive force and moving the induction heating coil along the strip, thereby causing the heated portion to move relative to the strip. It is moved in the longitudinal direction, and at the same time, a cooling medium such as cooling water is sprayed on the rear end part of the heating part to cool and solidify the part immediately after the thickening, thereby continuously increasing the thickness of the strip in the longitudinal direction. Therefore, it has an advantage that a thick part having a desired length can be easily formed in a desired region in the longitudinal direction of the strip.
[0003]
[Problems to be solved by the invention]
However, in this thickening method, during the thickening process, both sides of the thickened part are held on a predetermined axis by rollers or the like and the position is regulated, but the thickening process bends the strip material. May occur, and the straightness required for the strip as a product may be impaired.
[0004]
The reason for the bending that occurs during the thickening process is that the heated part of the strip that has been heated and has increased the thickness of the strip for a certain reason (the apparatus that performs the thickening process correctly corrects the straight strip). When held, the position of the axis of the strip occupies a position perpendicular to the mechanical axis), and the strip is bent in a dogleg shape around the heating part. It seems that it was because it was. Therefore, the present inventors obtain a displacement amount (deviation amount) from the processing reference axis of the heating portion of the strip during the thickening process (note that it is difficult to directly detect the displacement of the heating portion. The displacement in the vicinity of the heating part was detected and substituted), and a displacement, load or moment corresponding to the displacement was applied to each of the strip parts on both sides of the heating part so as to reduce the displacement. Control was performed. However, this method may correct the bending, but it does not always give a good result and is not always a satisfactory solution.
[0005]
The present invention has been made in view of such problems, and provides a method for increasing the thickness of a metal strip that can increase the thickness of the strip while preventing the occurrence of bending of the strip as much as possible. For the purpose.
[0006]
[Means for Solving the Problems]
As a result of earnest examination of the cause of the bending that occurs in the strip material, the present inventors have bent because the strip material is thickened in a state of being bent in a square shape around the heating part as described above. Rather, it was found that a bending occurred because of a step in the heating section. In other words, the softest part in the heated part where the wall thickness has increased is very small in plastic deformation resistance (for example, about 1/50 of the cold part), so the strips on both sides of the softest part are connected. Therefore, the strip material portions on both sides adjacent to the softest portion can be displaced so as to be independent from each other, and are displaced according to the force acting on the strip material portions on both sides. Therefore, the displacements on both sides of the softest part in the heating part do not necessarily coincide with each other and are shifted, and a step is generated in the heating part, and this step causes the bending after the thickening. Therefore, it is considered possible to suppress the occurrence of bending by minimizing the level difference that may occur in the heating unit.
[0007]
The present invention has been made on the basis of such knowledge, and the front strip portion and the rear strip portion located on both sides of the heating section of the metal strip are separated by the heating section, and the heating section side is freely separated. Considers two cantilever beams at the ends, and each cantilever acts on the cantilever beam By its own weight or, if a core is used, by its own weight acting on the cantilever and the load by the core, Calculate the amount of displacement from the machining reference axis that occurs at the tip of the cantilever beam, and then apply the corrective displacement, load, or bending moment to the cantilever beam to bring the free end of the cantilever beam first. Assuming that the calculated displacement amount is corrected and moved in the opposite direction, the correction displacement, load or bending moment applied to the cantilever is set based on the previously calculated displacement amount, The thickening process is performed in a state in which the set displacement, load, or bending moment is applied to the corresponding front strip portion or rear strip portion.
[0008]
In this way, the present invention regards the metal strip as two cantilever beams divided by the heating unit, calculates the displacement amount for each, and corrects the displacement amount so as to correct the displacement, load or Since the thickening process is performed with a bending moment applied, the free end position (heating part position) of each strip material part can be held near the machining reference axis during the thickening process. Steps that may occur can be suppressed, and bending can be prevented. As shown in the examples described later, according to the method of the present invention, the strip material portions on both sides of the heating unit are regarded as cantilever beams with the heating unit side as a free end, the deformation amount of the free end is calculated, It has been confirmed that bending can be suppressed to a small extent by setting a displacement for correction based on this and performing a thickening process. Therefore, in the present invention, two cantilevers in which the metal strip is divided by the heating unit It seems that what is regarded as a beam is very close to the actual phenomenon. Further, from the viewpoint of the effect of the present invention, it is inferred that the bending at the time of hot thickening is caused by integration of the steps generated in the heating portion with the progress of the thickening.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention locally heats a small region in the longitudinal direction of a metal strip to be thickened to form a heating portion, and compresses the heating portion while moving the heating portion relatively in the longitudinal direction of the metal strip. In the method for increasing the thickness of the metal strip, which increases the thickness by applying force and cools the rear end portion of the heating portion immediately after the thickness increase, the rear side strip located behind the heating portion during the thickness increasing process Basically, a straightening displacement, load or bending moment is applied to the front side strip portion located in front of the material portion and / or the heating portion to prevent the occurrence of bending.
[0010]
The strip material to be increased in thickness in the present invention may have an arbitrary cross-sectional shape such as an H-shaped material, an I-shaped material, a round pipe, a square pipe, a round bar, a square bar, and a plate material. Hereinafter, an example in which the present invention is applied to a square pipe will be described in detail with reference to the drawings.
[0011]
FIG. 7 is a schematic vertical sectional view showing a schematic configuration of an example of a thickening apparatus used for carrying out the method of the present invention, and FIG. 1 is a strip that is a square pipe to be thickened, 2 is a fixing fixture that fixes and holds one end of the strip 1 in place, and 3 is a strip that holds and presses the opposite end of the strip 1 This is a movable holder that applies a compressive force to the compressor 3A and is connected to a compression device 3A such as a hydraulic cylinder. Reference numeral 4 denotes an annular heating device capable of locally heating a small region in the longitudinal direction of the strip 1 to a temperature at which plastic deformation can be easily performed to form a heating unit 5. Here, an induction coil is used. . The heating device 4 includes a passage for a cooling medium such as cooling water inside, and a discharge hole for spraying the cooling medium 6 to a portion on the rear side in the moving direction (arrow B direction) of the heating unit 5. . Reference numeral 7 denotes a moving table that holds the heating device 4. The moving table 7 is connected to a moving mechanism such as a screw mechanism, and is configured to be able to move the heating device 4 along the strip 1 at a desired speed. Reference numeral 8 denotes a fixed-side guide roller that holds the rear-side strip portion 1a located on the rear side (fixed holder 2 side) of the strip 1 with respect to the heating unit 5, and is disposed at a fixed position. Reference numeral 9 denotes a moving-side guide roller that holds the front strip portion 1b located on the front side (movable holder 3 side) of the strip 1 with respect to the heating unit 5. The moving side guide roller 9 is held by a moving table 10 and can be moved along the strip 1 by the moving table 10. The moving table 10 is connected to a moving mechanism (not shown) for moving it, and is configured to be movable at the same speed in synchronization with the moving table 7 holding the heating device 4. In addition, 20 is a 1st curve correction means, 30 is a 2nd curve correction means, and it mentions later for details.
[0012]
The thickening operation in the thickening apparatus configured as described above is performed as follows. That is, in FIG. 1, one end of the strip 1 which is a square pipe to be thickened is fixed and held on the fixed holder 2, and the opposite end is held on the movable holder 3, and the guide rollers 8 and 9 It is held so as to be positioned on a predetermined machining reference axis OO. Next, the heating device 4 is positioned at the thickening start position S, and the movable holder 3 is pressed by the compression device 3A such as a hydraulic cylinder to cause the compressive force to act on the strip 1 and in that state, the strip by the heating device 4 is used. Heating of the material 1 is started, and a small region in the longitudinal direction of the strip 1 is locally heated to a temperature at which plastic deformation is easy to form a heating part 5, and a thickening due to compressive force occurs in the softest part of the heating part 5 Let At the same time, the heating device 4 and the moving side guide roller 9 positioned in front of the heating device 4 are moved at the same speed along the strip 1 to move the heating unit 5 in the longitudinal direction of the strip 1 and in parallel with the operation. Then, the cooling medium 6 is sprayed from the heating device 4 to the rear side of the heating unit 5 to cool and solidify the portion immediately after the thickening, whereby the strip 1 is continuously thickened in the longitudinal direction. Then, when the heating device 4 reaches a predetermined thickening end position, heating and pressurization are stopped, and the thickening operation is finished.
[0013]
When performing the above-described thickening processing operation, the strip 1 is positioned on both sides of the heating unit 5 by the fixed guide roller 8 and the moving guide roller 9, and its axial center is the processing reference axis O− over the entire length. It should be held to match O (see FIG. 1). However, in actuality, the heating portion 5 is displaced downward due to the weight of the strip portion between the guide rollers 8 and 9, and the heating portion 5 has a softest portion that causes a thickening deformation. At Step This causes a bend.
[0014]
The first bend correction means 20 and the second bend correction means 30 are provided to correct the downward displacement of the heating unit 5. In other words, the first bending correction means 20 applies a correction displacement or load to the rear strip portion 1a between the fixed guide roller 8 and the heating unit 5 to thereby apply the tip of the rear strip portion 1a ( The heating unit 5) corrects the position, and the second bending correction means 30 applies a correction displacement or load to the front strip portion 1b between the moving guide roller 9 and the heating unit 5. This corrects the position of the tip (heating unit 5) of the front strip portion 1b.
[0015]
The first bending correction means 20 includes a pair of pressure rollers 21 disposed so as to sandwich the upper and lower surfaces of the rear strip portion 1a, a moving frame 22 holding the pressure roller 21, and a moving frame 22 up and down. A pressure cylinder 23 that moves in the direction, a hydraulic servo device 25 that controls the supply of hydraulic pressure from the hydraulic source 24 to the pressure cylinder 23, a control device 26 that operates the hydraulic servo device 25, and the like. Based on a command from the control device 26, the rear strip portion 1a can be displaced by a predetermined amount, or a predetermined amount of load can be applied to the rear strip portion 1a, thereby leading the tip of the rear strip portion 1a. (Heating unit 5) can be displaced. Similarly, the second bending correction means 30 is also a pair of pressure rollers 31 disposed so as to sandwich the upper and lower surfaces of the front strip portion 1b, a moving frame 32 holding the pressure roller 31, and a moving frame. A pressure cylinder 33 that moves the cylinder 32 in the vertical direction, a hydraulic servo device 35 that controls the hydraulic pressure supply from the hydraulic source 24 to the pressure cylinder 33, a control device 36 that operates the hydraulic servo device 35, and the like. Based on a command from the control device 36, the front strip portion 1b can be displaced by a predetermined amount, or a predetermined amount of load can be applied to the front strip portion 1b, whereby the front end of the front strip portion 1b. (Heating unit 5) can be displaced. In addition, as the bending correction means 20 and 30 for correcting the tip positions of the rear strip portion 1a and the front strip portion 1b, displacement or load is applied to the strip portion as shown in FIG. The present invention is not limited to this, and a configuration may be adopted in which a bending moment is applied to the strip portion to displace the tip position, but in the following description, the illustrated bending correction means 20 and 30 are used.
[0016]
In the present invention, when the bending correction is performed by the first bending correction means 20 and the second bending correction means 30, the correction amount (the amount of correction or load applied to the strip portions 1a and 1b) is set. It is calculated | required by the calculation demonstrated below, It is characterized by the above-mentioned.
[0017]
First, the basic concept of correction amount calculation will be described. Now, as shown in FIG. _Z The thick portion 1c is formed, and the heating device 4 heats a certain position in the increased thickness region to form the heating portion 5 and the thickness is increased. During this thickening process, as shown in FIG. 1 (b), the rear strip portion 1a and the front strip portion 1b located on both sides of the heating section 5 of the strip 1 are respectively connected to the heating section 5 It is considered as two cantilever beams that are separated by the soft part) and have the heating part side as a free end. That is, the rear strip portion 1a is supported by the fixed guide roller 8 and is regarded as a cantilever having the heating portion 5 as a free end, and the front strip portion 1b is supported by the moving guide roller 9 and heated. It is regarded as a cantilever with the part 5 as a free end. As described above, when the strip portions 1a and 1b are regarded as cantilever beams, by their own weight acting on the cantilever beams, or when some load is applied to the cantilever beams, The free end (tip) of the cantilever will be displaced downward from the machining reference axis OO, and the amount of displacement δ ₂ , Δ _Three Depends on the length of the cantilever and the applied load. Therefore, this displacement δ ₂ , Δ _Three Is calculated. This calculation can be performed using known calculation techniques for cantilever deflection.
[0018]
Next, as shown in FIG. 1 (c), each strip portion 1a, 1b is regarded as a cantilever beam, and this is applied by the pressure rollers 21, 31 of the first bending correction means 20 and the second bending correction means 30. The correction displacement (push-up amount by each pressure roll) or load applied to each of the pressure rollers 21 and 31 is assumed to be corrected by correcting the displacement of each free end (displacement amount calculated previously). (The pushing force applied to each pressure roll) ₂ , Δ _Three Ask based on. That is, the free end of each cantilever is calculated by the displacement δ obtained by calculation previously. ₂ , Δ _Three Is considered to be an appropriate amount, preferably its displacement δ ₂ , Δ _Three The amount of correction or the magnitude of the load (correction amount) is determined so that the amount can be displaced upward by an amount corresponding to. And the displacement or load for correction | amendment of the calculated | required magnitude | size is added to each strip material part 1a, 1b, and a thickening process is performed in the state. As a result, the tip of each strip portion 1a, 1b (heating unit 5), that is, the displacement of the free end from the machining reference axis when regarded as a cantilever beam is suppressed, and there is a possibility that it will occur in the heating unit 5. The thickening process can be performed while suppressing a certain level difference, and the occurrence of bending can be prevented.
[0019]
The above is the basic concept of the correction amount calculation in the present invention. By the way, the amount of displacement of the free end of each cantilever during thickening processing δ ₂ , Δ _Three Varies depending on the distance between the guide roller 8 and the heating unit 5 and the distance between the heating unit 5 and the guide roller 9. In the thickening apparatus shown in FIG. 1, the guide roller 8 that supports the rear strip portion 1 a is in a fixed position, and the guide roller 9 that supports the front strip portion 1 b moves together with the heating device 4. Therefore, the displacement δ of the free end of the rear strip portion 1a as the heating device 4 moves (and accordingly as the heating unit 5 moves). ₂ Increases and the displacement δ of the free end of the front strip portion 1b _Three Is almost constant. This is shown in a graph in FIG. In FIG. 1 and FIG. 2, point S is a thickening start position, and point E is a thickening end position.
[0020]
In the present invention, the correction displacement or load magnitude (correction amount) applied to each strip portion 1a, 1b is such a displacement amount δ. ₂ , Δ _Three This is set in consideration of the characteristics. At that time, as the correction amount, the amount of displacement of the free end of the strip portion is the displacement amount δ. ₂ As in the case of changing according to the position of the heating part during the thickening process, it may be set to be constant during the thickening process, or may be changed according to the position of the heating part. You may set so that it may change continuously or in steps according to the amount of displacement.
[0021]
When the correction displacement or load applied to each strip portion 1a, 1b is set to change continuously or stepwise according to the position of the heating part, the heating part 5 moves to a plurality of positions in advance. Each displacement amount δ ₂ , Δ _Three 2 to obtain a characteristic curve as shown in FIG. 2, and then, for each position of the heating unit 5, the free end of each cantilever is determined by the previously calculated displacement amount δ. ₂ , Δ _Three The amount of correction or the amount of load that can be displaced upward by an amount corresponding to is obtained. Thereby, the magnitude of the displacement or load for correction with respect to the position of the heating unit is set in advance. Then, when performing the thickening process, as the heating unit 5 moves, a correction displacement or load having a size set in accordance with the position of the heating unit 5 is applied to each strip portion 1a, 1b. In addition, each bending correction means 20, 30 is controlled programmatically, and the thickening process is performed in that state. Thereby, no matter which position the heating unit 5 moves, the free ends (heating units 5) of the respective strip portions 1a and 1b are held substantially on the processing reference axis so that no step is generated in the heating unit 5. It can be restrained to increase the thickness and prevent bending.
[0022]
Next, when the correction displacement or load applied to the strip portion 1a is set to be constant regardless of the movement of the heating portion, the displacement amount δ having the characteristics shown in FIG. ₂ So that the free end of the cantilever can be displaced upward (a specific method will be described later) and set to that value. Then, the thickening process is performed in a state where the correction displacement or load having the set size is applied to the strip portion 1a. In this case, as shown in FIG. 2, the displacement δ of the free end of the rear strip portion 1a ₂ However, since the amount of correction applied to the rear strip portion 1a is constant, the heating portion 5 at the free end of the rear strip portion 1a during the thickening process. Although the displacement from the machining reference axis cannot be controlled to always be zero, it can be significantly reduced as compared with the case where no correction is made, thereby suppressing the occurrence of bending. The amount of displacement δ generated in the front strip portion 1b _Three Is substantially constant regardless of the position of the heating part 5, so that the correction displacement or load applied to the front strip portion 1b is the displacement amount δ. _Three Is set to be corrected to 0, whereby the heating part 5 at the free end of the front strip portion 1b during the thickening process can be held on the processing reference axis. Further, the displacement amount δ generated in the front strip portion 1b _Three Is negligible and can be ignored, the correction displacement or load applied to the front strip portion 1b is set to 0, and therefore the front strip portion 1b may not be corrected.
[0023]
In the case where the displacement or load for correction applied to the rear strip portion 1a is constant during the thickening process, specific methods for obtaining the displacement or load for correction are, for example, the following methods: Can be mentioned.
[0024]
(1) Displacement amount δ at start of thickening (when heating unit 5 is at thickening start position S) _2S And the displacement δ _2S The displacement or load for correction for correcting the value to 0 is calculated, and then the displacement δ at the end of the thickening (when the heating unit 5 is at the thickening start position E) _2E And the displacement δ _2E The displacement or load for straightening to correct to 0 is calculated, and the average value of the displacement or load for straightening at the start and end of thickening is applied to the rear strip portion 1a. And set.
[0025]
(2) Displacement amount δ when heating unit 5 is at an appropriate position M (preferably the center position) in the thickening region _2M And the displacement δ _2M Is calculated as a displacement or load for correction to be applied to the rear strip portion 1a.
[0026]
(3) Displacement amount δ during thickening process ₂ Is calculated, and a correction displacement or load for correcting the displacement amount of the average value to 0 is calculated, and this is set as a correction displacement or load applied to the rear strip portion 1a.
[0027]
Next, in carrying out the above method (1), the amount of displacement δ at the start of thickening _2S , Δ _3S And displacement amount δ at the end of thickening _2E , Δ _3E An example of a calculation method for calculating the value will be described.
[0028]
(1) Deflection that occurs at the start of thickening
As shown to Fig.3 (a), the heating apparatus 4 shall be in the thickening start position S, and each part dimension is defined as shown in FIG. Assuming that the strip 1 is separated at the softest part of the heating unit 5, the rear strip portion 1 a supported by the stationary guide roller 8 and the front strip portion supported by the moving guide roller 9. As shown in FIGS. 3 (b) and 3 (c), 1b is a cantilever, and a constant distributed load q (kg / cm) due to its own weight acts on the entire length of each 1b. Displaces downward. The displacement δ of the free end of the rear strip portion 1a at this time _2s Can be calculated by Equation 1, and the displacement δ of the free end of the front strip portion 1b _3s Can be calculated by Equation 2.
[0029]
[Expression 1]

[0030]
[Expression 2]

[0031]
(2) Deflection occurring at the end of thickening
As shown to Fig.4 (a), the heating apparatus 4 shall be in the thickening completion position E, and each part dimension is defined as shown in FIG. Then, it is considered that the strip 1 is cut off at the softest part of the heating unit 5 at the end of thickening, and the strip portions 1a and 1b on both sides thereof form a cantilever.
[0032]
▲ 1 ▼ Rear strip part 1a
The rear strip portion 1a supported by the fixed guide roller 8 is a cantilever as shown in FIG. 4 (b). The amount of displacement δ below the free end of the cantilever at this time _2E In order to simplify the calculation, a constant distributed load q due to its own weight acts on the area where the thickness is not increased, and the thick portion 1c where the thickness is increased is the entire thick portion 1c at the center. Weight P _Z Is acting as a concentrated load. This concentrated load P _Z If the rate of wall thickness is β,
P _Z = QL _Z (1 + β)
It can be calculated with
[0033]
First, as shown in FIG. 4 (c), it is assumed that only the distributed load q acts on the cantilever beam (strip portion 1a) (assuming that the thick portion has no weight), and the free end displacement amount δ. _2q Calculate Displacement amount δ at point S, which is the position to start thickening ₂ Is the displacement δ of the free end of the cantilever shown in FIG. _2S be equivalent to. Therefore, the displacement amount δ of the S point ₂ Is given by Equation 3.
[0034]
[Equation 3]

[0035]
Next, the inclination angle θ at point S ₂ Becomes Equation 4.
[0036]
[Expression 4]

[0037]
Therefore, the downward displacement δ from the point S at the tip of the cantilever ₂ ′ Is expressed by Equation 5, and the free end displacement δ _2q Can be calculated by Equation 6.
[0038]
[Equation 5]

[0039]
[Formula 6]

[0040]
Next, as shown in FIG. 4 (d), the concentrated load P is applied to the cantilever. _Z The displacement δ of the free end _2Z Calculate First, the displacement amount δ of the S point _2Z 'Becomes Equation 7. Also, the displacement angle θ at that position _2Z Since Equation 8 is given, the downward displacement amount δ from the point S of the free end of the cantilever beam _2Z ″ Is expressed by Equation 9. Accordingly, the displacement δ at the free end _2Z Can be calculated by Equation 10.
[0041]
[Expression 7]

[0042]
[Equation 8]

[0043]
[Equation 9]

[0044]
[Expression 10]

[0045]
As shown in FIG. 4B, the distributed load q and the concentrated load P are applied to the cantilever beam (strip portion 1a). _Z Displacement amount of free end when _2E Is the displacement δ of the free end when only the distributed load q is applied _2q [See FIG. 4 (c)] and concentrated load P _Z Displacement amount δ of free end when only _2Z Since [see FIG. 4 (d)] is added, the amount of downward displacement δ generated at the free end of the rear strip portion 1a at the end of the thickening process is eventually obtained. _2E Can be calculated by Equation 11.
[0046]
[Expression 11]

[0047]
▲ 2 ▼ Front strip part 1b
On the other hand, the front strip portion 1b supported by the moving guide roller 9 becomes a cantilever having dimensions as shown in FIG. 4 (e) even at the end of the thickening, which is shown in FIG. 3 (c). It is the same as the cantilever beam at the start of thickening. Therefore, the displacement δ at the end of thickening _3E Is the displacement amount δ at the start of thickening _3S And is expressed by Equation 12.
[0048]
[Expression 12]

[0049]
As described above, the displacement amount of the free end of each strip portion 1a, 1b at the start of thickening and at the end of thickening can be calculated, and based on this, the displacement or load for correction can be obtained.
[0050]
Although the above description showed the case where the thickening process is performed in a state where the thickened portion of the strip 1 is free as shown in FIG. 7, the present invention is not limited to this case. For example, FIG. As shown in FIG. 2, even when the thickening process is performed in a state in which the core 12 such as a heat treatment die is inserted so as to be located inside the thick part 1e formed by the thickening process in the strip material 1. Applicable. The core 12 used here has a length equal to or greater than the length of the thick portion 1c formed by the thickening process, and the outer surface of the core 12 is brought into contact with the inner surface of the strip 1 at both ends thereof. A protrusion 12a is provided for maintaining a constant distance from the inner surface of the strip 1. A connecting rod 13 is connected to the core 12, but the connecting rod 13 is provided only for positioning the core 12 in the longitudinal direction and does not support the weight of the core 12. Accordingly, the weight of the core 12 is held by the strip 1, in other words, the weight of the core 12 acts as a load on the strip 1, and the weight is concentrated by the protrusions 12 a at both ends of the core 12. Acts as In addition, the structure except the point which provided the core 12 is the same as that of the thickening processing apparatus shown in FIG.
[0051]
As shown in FIG. 9, when the thickening process is performed with the core 12 inserted into the strip 1, when the thickening is started, the inner surface of the thick portion 1 c formed by the thickening is the core 12. It is pressed against the outer peripheral surface, and the thickness increases while being integrated. In this way, while the thick wall portion is in close contact with the core 12 and the thickening proceeds while being integrated, the strip material 1 and the core 12 act like one end support beam, and the heating portion 5 There are not many steps. However, during the period from the start of the increase in thickness until the thick portion is in close contact with the core 12, the strip portions 1a and 1b located on both sides of the heating unit 5 are not constrained by the core 12, so each can freely It can move and behaves like a cantilever beam separated by the softest part of the heating part 5. Therefore, the amount of downward displacement of the free ends (heating unit 5) of each strip portion 1a, 1b is different, which causes bending.
[0052]
Therefore, the present invention can be applied to this case. That is, at the start of the thickening process, the strip portions 1a and 1b on both sides of the heating unit 5 are cut off at the softest part of the heating unit 5 and are considered as cantilever beams with the heating unit side as a free end, The amount of displacement below the free end of is calculated. Naturally, the concentrated load by the core 12 is taken into consideration in the calculation at this time. Then, the displacement or load for correction is obtained so that the displacement amount obtained by the calculation can be corrected, and this is applied to the strip parts 1a and 1b by the first and second bending correction means 20 and 30, respectively. Increase the thickness in the added state. This prevents the occurrence of a step that may occur in the heating part 5 from the start of the thickening until the thick part is integrated with the core, and performs the thickening process while preventing the occurrence of bending. Can do. In addition, it is preferable to add the correction displacement or load applied to each strip portion 1a, 1b at the start of thickening as it is even after the thick portion is integrated with the core.
[0053]
Next, an example of a method for calculating the amount of displacement of the free end of each strip portion 1a, 1b at the start of thickening when the core 12 is used will be described. As shown to Fig.5 (a), the heating apparatus 4 shall be in the thickening start position S, and each part dimension is defined as shown in FIG. Also in this case, it is considered that the strip 1 is cut off at the softest portion of the heating unit 5 at the thickening start position, and the strip portions 1a and 1b on both sides thereof form a cantilever.
[0054]
▲ 1 ▼ Rear strip part 1a
First, as shown in FIG. 5C, the rear strip portion 1a held by the fixed guide roller 8 is regarded as a cantilever beam, and only the distributed load q acts on the rear strip portion 1a (core). 12), the displacement δ of the free end _2q Calculate This displacement δ _2q Can be calculated by Equation 13.
[0055]
[Formula 13]

[0056]
Next, as shown in FIG. 5 (d), the concentrated load P by the core 12 is applied to the free end of the cantilever (the strip portion 1a). ₁ The displacement δ of the free end _{twenty one} Calculate In addition, although the concentrated load by the core 12 is acting in the position a little away from the free end (heating part 5) of the strip part 1a, since the shift | offset | difference is small, it abbreviate | omits. Free end displacement δ _{twenty one} Can be calculated by Equation 14.
[0057]
[Expression 14]

[0058]
As shown in FIG. 5B, the distributed load q and the concentrated load P are applied to the cantilever beam. ₁ Displacement amount of free end when _21S Is the displacement δ when only the distributed load q is applied _2q [See FIG. 5 (c)] and displacement δ when only concentrated load is applied _{twenty one} Since [see FIG. 5 (d)] is added, the amount of downward displacement δ produced at the free end of the rear strip portion 1a is eventually obtained. _21S Can be calculated by Equation 15.
[0059]
[Expression 15]

[0060]
▲ 2 ▼ Front strip part 1b
As shown in FIG. 5 (f), the front strip portion 1 b held by the moving guide roller 9 is regarded as a cantilever beam. First, assuming that only the distributed load q acts on it (assuming that the concentrated load by the core 12 does not act), the displacement δ of the free end _3q Calculate This displacement δ _3q Can be calculated by Equation 16.
[0061]
[Expression 16]

[0062]
Next, as shown in FIG. 5 (g), the distance L corresponding to the increased thickness from the free end of the cantilever (strip portion 1b). _N Concentrated load P due to the core 12 at a position far away from the center (end position of thickening, ie, point E) ₂ The displacement δ of the free end ₃₂ Calculate In addition, although the concentrated load by the core 12 is acting on the position a little away from the thickness increase end position E, since the deviation is small, it is omitted.
[0063]
First, the displacement amount δ at point E ₃₂ 'Is given by Equation 17. Also, the displacement angle θ at that position _Three Since Equation 18 is obtained, the downward displacement amount δ from the point E at the free end of the cantilever beam ₃₂ ″ Is expressed by Equation 19. Therefore, the tip displacement δ _3Z Can be calculated by Equation 20.
[0064]
[Expression 17]

[0065]
[Expression 18]

[0066]
[Equation 19]

[0067]
[Expression 20]

[0068]
As shown in FIG. 5E, the distributed load q and the concentrated load P are applied to the cantilever beam. ₂ Displacement amount of free end when _32S Is the displacement δ when only the distributed load q is applied _3q [See FIG. 5 (f)] and concentrated load P ₂ Displacement δ when only ₃₂ Since [see FIG. 5G] is added, the amount of downward displacement δ generated at the free end of the front strip portion 1b is eventually obtained. _32S Can be calculated by Equation 21.
[0069]
[Expression 21]

[0070]
As described above, when the core 12 is used, the amount of displacement of the free ends (heating portions) of the strip material portions 1a and 1b at the start of the increase in thickness can be calculated, and based on this, the displacement or load for correction can be calculated. Can be sought.
[0071]
The above explanation is about the case where the method of the present invention is applied to the thickening process using the apparatus having the configuration shown in FIG. 7 or FIG. However, it can be changed as appropriate. For example, instead of using the moving side guide roller 9 that moves in synchronization with the heating device 4, a guide roller arranged at a fixed position may be used. In that case, since the distance between the heating unit 5 and the guide roller changes as the thickness increases, the displacement δ of the free end of the front strip portion 1b. _Three In calculating the amount of correction and the amount of correction, the change in the interval may be considered in the same manner as in the rear strip portion 1a. Further, in the apparatus shown in FIGS. 7 and 9, the strip material portions 1a and 1b on both sides of the heating unit 5 are held by two sets of guide rollers 8 and 9 arranged at intervals, respectively. Changes such as increasing the number of rollers or using another mechanism such as a clamp may be performed. In that case, in calculating the displacement amount of the free end of the cantilever beam, the characteristics of the mechanism holding the cantilever beam may be considered.
[0072]
Furthermore, in the above description, it is assumed that the strip material used for the thickening process is straight. By the way, some strip materials used for the thickening process already have a bend before being subjected to the thickening process. When the strip material having a bend in the cold state is set in the thickening apparatus shown in FIG. 7 and the thickening process is performed, the strips on both sides of the portion of the strip material to be thickened. When the material portions 1a and 1b are constrained to a predetermined processing reference axis by a plurality of guide rollers 8 and 9 arranged at intervals, the portions of the strip material constrained by the guide rollers 8 and 9 become the processing reference axis. Although it is held on the center, other parts are not necessarily located on the machining reference axis, and in particular, the heating unit is often displaced from the machining reference axis. The present invention can also be applied to this case. That is, the strip portions respectively held by the guide rollers 8 and 9 are regarded as cantilever beams separated by the heating portion, and in calculating the amount of displacement of each free end, the bending that the strip has when cold is held. Taking into consideration and correcting the obtained displacement amount, the straightening displacement or load applied to each strip portion is obtained, and the thickening process is performed with the straightening displacement or load applied to each strip portion. May occur in the heated part during thickening processing Step Can be suppressed to prevent bending.
[0073]
【Example】
[Example 1]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) are shown in FIG.
▲ 2 ▼ Thickening conditions
Test strip material: 300 mm square x 12 mm thick x 15000 mm long square steel pipe
Increased length L _Z = 1150mm, increased thickness at 3 locations
Thickening rate β = 100%
[0074]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 11 mm with respect to the entire length.
[0075]
(4) Displacement calculation and correction displacement calculation
The strip portions 1a and 1b on both sides of the heating unit 5 were regarded as cantilever beams, and the displacement amount of the free end was calculated at the start and end of the thickening, and the results shown in Table 1 were obtained. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement amount obtained by the calculation to 0 is calculated at the start and end of the thickening, respectively, and the results shown in Table 1 are obtained. Obtained. In Table 1 and Tables 2 to 6 described later, “fixed side” relates to the rear strip portion 1 a located behind the heating unit 5, and “moving side” refers to the front of the heating unit 5. It is related with the front strip material part 1b located in the. The unit in the table is mm.
[0076]
[Table 1]

[0077]
(5) Push-up amount setting
For the fixed side (rear strip portion 1a), the average value of the push-up amount at the start of thickening and the push-up amount at the end of thickening is the push-up amount Δy for correction. _m Was set. That is,
Δy _m = (0.0215 + 0.374) /2≈0.2 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0078]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = Pushed up by 0.2 mm, and held in that state to perform a thickening process. After the thickening process, the bending with respect to the total length of the thickened strip was measured and found to be ± 4 mm, and the bending could be greatly reduced as compared with the case without correction.
[0079]
[Example 2]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) are shown in FIG.
▲ 2 ▼ Thickening conditions
Specimen strip material: 250 mm square x 9 mm thickness x 15000 mm long square steel pipe
Increased length L _Z = 850mm, increased thickness at 3 locations
Thickening rate β = 100%
[0080]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 12 mm with respect to the entire length.
[0081]
(4) Displacement calculation and correction displacement calculation
Considering the strip material portions 1a and 1b on both sides of the heating section 5 during the thickening process as cantilever beams, the displacement amount of the free end is calculated at the start and end of the thickening, and the results shown in Table 2 are obtained. It was. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement amount obtained by the calculation to 0 is calculated at the start and end of the thickening, respectively, and the results shown in Table 2 are obtained. Obtained.
[0082]
(5) Push-up amount setting
For the fixed side (rear strip portion 1a), the average value of the push-up amount at the start of thickening and the push-up amount at the end of thickening is the push-up amount Δy for correction. _m Was set. That is,
Δy _m = (0.0307 + 0.365) /2≈0.2 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0083]
[Table 2]

[0084]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = Pushed up by 0.2 mm, and held in that state to perform a thickening process. When the bending with respect to the total length of the thickened strip was measured after the thickening process, it was ± 4 mm, and the bending could be greatly reduced as compared with the case without correction.
[0085]
[Example 3]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) are shown in FIG.
▲ 2 ▼ Thickening conditions
Specimen strip: 175 mm square x 9 mm thickness x 12000 mm long square steel pipe
Increased length L _Z = 550mm, increased thickness at 3 locations
Thickening rate β = 66.7%
[0086]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 10.5 mm with respect to the entire length.
[0087]
(4) Displacement calculation and correction displacement calculation
Considering the strip parts 1a and 1b on both sides of the heating section 5 during the thickening process as cantilever beams, the amount of displacement of the free end is calculated at the start and end of the thickening, and the results shown in Table 3 are obtained. It was. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement amount obtained by the calculation to 0 is calculated at the start and end of the thickening, respectively, and the results shown in Table 3 are obtained. Obtained.
[0088]
[Table 3]

[0089]
(5) Push-up amount setting
For the fixed side (rear strip portion 1a), the average value of the push-up amount at the start of thickening and the push-up amount at the end of thickening is the push-up amount Δy for correction. _m Was set. That is,
Δy _m = (0.0646 + 0.419) /2≈0.24 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0090]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = Pushed up by 0.24 mm, and held in that state to perform a thickening process. When the bending with respect to the total length of the thickened strip was measured after the thickening process, it was ± 3 mm, and the bending could be greatly reduced as compared with the case without correction.
[0091]
[Example 4]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) have the dimensions shown in FIG. 6 (b).
Core: Weight W = 500kg, Length L = 1460mm
▲ 2 ▼ Thickening conditions
Test strip material: 300 mm square x 12 mm thick x 15000 mm long square steel pipe
Increased length L _Z = 1150mm, increased thickness at 3 locations
Thickening rate β = 100%
[0092]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 7.5 mm with respect to the entire length.
[0093]
(4) Displacement calculation and correction displacement calculation
The strip material portions 1a and 1b on both sides of the heating unit 5 at the start of thickening were regarded as cantilever beams, and the amount of displacement of the free end was calculated at the start of thickening, and the results shown in Table 4 were obtained. Further, at the end of the increase in thickness, the strip material was regarded as a doubly supported beam integrated with the core, and the amount of displacement of the heating part was calculated to obtain the results shown in Table 4. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement obtained by the calculation to 0 at the start and end of the thickening is calculated, and the results shown in Table 4 are obtained. Obtained.
[0094]
[Table 4]

[0095]
(5) Push-up amount setting
For the fixed side (rear strip material portion 1a), the push-up amount at the start of thickening is set to the push-up amount Δy for correction. _m Was set. That is,
Δy _m = 0.182 ≒ 0.18 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0096]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = It was pushed up by 0.18 mm, and the thickening process was performed while maintaining the state. When the bending with respect to the total length of the thickened strip was measured after the thickening process, it was ± 3 mm, and the bending could be greatly reduced as compared with the case without correction.
[0097]
[Example 5]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) have the dimensions shown in FIG. 6 (b).
Core: Weight W = 400kg, Length L = 1350mm
▲ 2 ▼ Thickening conditions
Specimen strip material: 250 mm square x 9 mm thickness x 15000 mm long square steel pipe
Increased length L _Z = 850mm, increased thickness at 3 locations
Thickening rate β = 100%
[0098]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 8.0 mm with respect to the entire length.
[0099]
(4) Displacement calculation and correction displacement calculation
The strip material portions 1a and 1b on both sides of the heating unit 5 at the start of thickening were regarded as cantilever beams, and the amount of displacement at the free end was calculated at the start of thickening, and the results shown in Table 5 were obtained. Further, at the end of the thickening, the strip material was regarded as a doubly supported beam integrated with the core, and the displacement amount of the heating part was calculated to obtain the results shown in Table 5. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement amount obtained by the calculation to 0 is calculated at the start and end of the thickening, respectively, and the results shown in Table 5 are obtained. Obtained.
[0100]
[Table 5]

[0101]
(5) Push-up amount setting
For the fixed side (rear strip material portion 1a), the push-up amount at the start of thickening is set to the push-up amount Δy for correction. _m Was set. That is,
Δy _m = 0.324 ≒ 0.32 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0102]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = It was pushed up by 0.32 mm, and the thickening process was performed while maintaining this state. When the bending with respect to the total length of the thickened strip was measured after the thickening process, it was ± 3.5 mm, and the bending could be greatly reduced as compared with the case without correction.
[0103]
[Example 6]
▲ 1 ▼ Thickening processing equipment
6 (a) and 6 (b) have the dimensions shown in FIG. 6 (b).
Core: Weight W = 400kg, Length L = 1350mm
▲ 2 ▼ Thickening conditions
Specimen strip: 175 mm square x 9 mm thickness x 12000 mm long square steel pipe
Increased length L _Z = 550mm, increased thickness at 3 locations
Thickening rate β = 66.7%
[0104]
▲ 3 ▼ Thickening without correction
When the pushing-up amount by the pressure rollers 21 and 31 was set to 0 and the thickening process was performed, the obtained thickening strip was bent downward by 24 mm with respect to the entire length.
[0105]
(4) Displacement calculation and correction displacement calculation
The strip material portions 1a and 1b on both sides of the heating unit 5 at the start of thickening were regarded as cantilever beams, and the displacement amount of the free end was calculated at the start of thickening, and the results shown in Table 6 were obtained. Further, at the end of the thickening, the strip material was regarded as a doubly supported beam integrated with the core, and the amount of displacement of the heating part was calculated to obtain the results in Table 6. Further, the pushing amount (correcting displacement) Δy by the pressure rollers 21 and 31 for correcting the displacement amount obtained by the calculation to 0 at the start and end of the thickening is calculated, and the results shown in Table 6 are obtained. Obtained.
[0106]
[Table 6]

[0107]
(5) Push-up amount setting
For the fixed side (rear strip material portion 1a), the push-up amount at the start of thickening is set to the push-up amount Δy for correction. _m Was set. That is,
Δy _m = 0.624 ≒ 0.62 (mm)
Was set. On the other hand, since the displacement amount on the moving side (the front strip portion 1b) is very small, it is determined that correction is not particularly necessary, and the push-up amount is set to zero.
[0108]
▲ 6 ▼ Thickening process and results
Push-up amount Δy in which the rear strip portion 1a is set by the pressure roller 21 of the first bending correction means before the start of the thickening process. _m = 0.62 mm was pushed up and held in that state for thickening. When the bending with respect to the total length of the thickened strip was measured after the thickening process, it was ± 4.5 mm, and the bending could be greatly reduced as compared with the case without correction.
[0109]
【The invention's effect】
As described above, according to the method of the present invention, the front strip portion and the rear strip portion located on both sides of the softest portion of the heating portion of the metal strip are separated at the softest portion, and the softest portion side is freely separated. Considers two cantilever beams at the ends and acts on each cantilever beam By its own weight or, if a core is used, by its own weight acting on the cantilever and the load by the core, The amount of displacement from the machining reference axis that occurs at the free end of each cantilever beam is calculated, and based on the amount of displacement, correction for applying to the cantilever beam to correct the displacement of the free end of the cantilever beam Obtain the displacement, load or bending moment, and increase the thickness in the state where the two straightening displacements, load or bending moment obtained for the two cantilever beams are added to the corresponding front strip portion and rear strip portion, respectively. By adopting the configuration to perform the processing, it is possible to correct the deflection by a calculation that closely approximates the deflection deformation that actually occurs in the strip during the thickening processing. While correcting the vicinity, it is possible to suppress the level difference that may occur in the heated part, while preventing the occurrence of bending Increased thickness Processing can be performed. Therefore, the method of the present invention has an effect that it is possible to obtain a thickened strip with little bending.
[Brief description of the drawings]
1A and 1B are diagrams illustrating the principle of the method of the present invention, in which FIG. 1A is a schematic side view showing a state during thickening processing, and FIG. (C) is a schematic side view showing a state in which the displacement is corrected
FIG. 2 is a graph showing the relationship between the amount of displacement of the free ends of the strip portions 1a and 1b shown in FIG.
FIGS. 3A and 3B are diagrams for explaining a calculation condition of a displacement amount at the start of thickening, in which FIG. 3A is a schematic side view showing a state at the start of thickening, and FIG. (C) is a schematic side view showing the self-weight and displacement acting on the strip portion 1b regarded as a cantilever beam.
FIGS. 4A and 4B illustrate calculation conditions for the amount of displacement at the end of thickening. FIG. 4A is a schematic side view showing a state at the end of thickening. FIGS. 4B, 4C, and 4D are cantilever beams. Schematic side view showing the weight, load and displacement acting on the strip material portion 1a considered, (c) is a schematic side view showing the weight and displacement acting on the strip material portion 1b regarded as a cantilever beam
FIG. 5 explains the calculation condition of the displacement amount at the start of thickening, (a) is a schematic side view showing the state at the start of thickening, and (b), (c) and (d) are cantilever beams; Schematic side view showing the weight, load and displacement acting on the strip material portion 1a considered, (e), (f) and (g) are the weight, load and displacement acting on the strip material portion 1b regarded as a cantilever beam. Schematic side view showing
6A and 6B show a thickening apparatus used in Examples 1 to 6, in which FIG. 6A is a schematic side view at the start of thickening, and FIG. 6B is a schematic side view at the end of thickening.
FIG. 7 is a schematic vertical sectional view showing an example of a thickening apparatus used in the method of the present invention.
8 is a schematic cross-sectional view in the direction of arrow AA in FIG.
FIG. 9 is a schematic vertical sectional view showing another example of the thickening apparatus used in the method of the present invention.
[Explanation of symbols]
1 Strip material
1a Rear strip material part
1b Front side strip part
1c Thick part
2 Fixing fixture
3 Movable holder
3A compressor
4 Heating device
5 Heating part
6 Cooling medium
7 Moving table
8 Fixed-side guide roller
9 Moving guide roller
10 Moving table
12 Core (heat treatment die)
20 First bend correction
21 Pressure roller
23 Pressure cylinder
30 Second bending correction means
31 Pressure roller
33 Pressure cylinder

Claims (5)

A small area in the longitudinal direction of the metal strip to be thickened is locally heated to form a heating section, and a compressive force is applied while moving the heating section relative to the longitudinal direction of the metal strip. In the method of increasing the thickness of the metal strip and cooling the rear end portion of the heating portion immediately after the thickness increase, the front strip portion and the rear strip positioned on both sides of the heating portion of the metal strip each part is disconnected by the heating unit, regarded as two cantilever of the heating unit side and a free end, each of the cantilever and thus cantilevers the own weight acting on the cantilever The amount of displacement from the machining reference axis that occurred at the free end of the cantilever was calculated, and then the free end of the cantilever was calculated first by applying a corrective displacement, load or bending moment to the cantilever. It shall be corrected and moved in the opposite direction to the direction that produces the displacement. Set the corrective displacement, load or bending moment applied to the cantilever beam based on the previously calculated displacement amount, and set the displacement, load or bending moment of the set size to the corresponding front side. Thickening of the metal strip, which suppresses the level difference that may occur in the heated part by performing the thickening process in the state added to the strip or rear strip, and prevents the occurrence of bending Processing method. A core is arranged so that it is located inside the thick part formed by the thickening process of the metal tube that is the metal strip to be thickened, and a small area in the longitudinal direction of the metal strip The heating part is heated locally to form a heating part, and the heating part is thickened by applying a compressive force while relatively moving in the longitudinal direction of the metal strip, and the rear end part of the heating part is increased. In the method of increasing the thickness of the metal strip that is cooled immediately after the meat, the front strip portion and the rear strip portion positioned on both sides of the heating section of the metal strip are separated by the heating section, and the heating section It is considered as two cantilever beams with the side as a free end. For each cantilever beam, from its own weight acting on the cantilever beam and the machining reference axis generated at the free end of the cantilever beam by the load from the core The amount of displacement is then calculated, and then the cantilever is subjected to correction displacement, load or By applying a bending moment, the free end of the cantilever beam is corrected and moved in a direction opposite to the direction of the previously calculated displacement amount. Is set based on the amount of displacement calculated previously, and the thickness is increased in a state where the displacement, load or bending moment of the set size is applied to the corresponding front strip portion or rear strip portion. A method for increasing the thickness of a metal strip, characterized by suppressing a step that may occur in a heated portion by performing processing and preventing the occurrence of bending. The increase in the metal strip according to claim 1 or 2, wherein the straightening displacement, load or bending moment applied to the front strip portion and the rear strip portion is set constant during the thickening process. Meat processing method. When setting the magnitude of the correction displacement, load or bending moment applied to the front strip portion and the rear strip portion, the heating part is at the thickening start position and the thickening end position, respectively. The front strip portion and the rear strip portion are regarded as cantilever beams, the amount of displacement from the machining reference axis that occurs at the free end of the cantilever beam is calculated, and the thickening start position and thickening end position 4. The method for increasing the thickness of a metal strip according to claim 3, wherein a magnitude of the displacement, load or bending moment for correction is set based on the displacement amount obtained for each of the above . The correction displacement, load, or bending moment applied to the front strip portion and the rear strip portion varies depending on the position of the heating unit, and a value corresponding to the amount of displacement of the free end of the cantilever. 3. The method for increasing the thickness of a metal strip according to claim 1 or 2, wherein the method is set programmatically .

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