JPH08257775A - Joining method for hot rolled billets - Google Patents
Joining method for hot rolled billetsInfo
- Publication number
- JPH08257775A JPH08257775A JP7061160A JP6116095A JPH08257775A JP H08257775 A JPH08257775 A JP H08257775A JP 7061160 A JP7061160 A JP 7061160A JP 6116095 A JP6116095 A JP 6116095A JP H08257775 A JPH08257775 A JP H08257775A
- Authority
- JP
- Japan
- Prior art keywords
- welding
- steel
- tack
- laser output
- laser
- 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.)
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- Laser Beam Processing (AREA)
- Metal Rolling (AREA)
Abstract
(57)【要約】
【目的】 仮付溶接時の溶落ちをなくし、仮付溶接に続
くの圧延工程で鋼片の破断を防ぐことができる熱間圧延
鋼片の接合方法を提供する。
【構成】 高温の先行鋼片の後端面と後行鋼片の前端面
とを突き合わせ、この突合せ部に沿ってレーザ溶接で突
合せ部を仮付溶接し、引き続き仮付溶接した鋼片を鋼片
厚み方向に圧下して両鋼片を接合する方法において、溶
接速度を一定に保持し、鋼片の一方の側端から仮付溶接
を開始し、レーザ出力を漸増しながら側端部を仮付溶接
し、レーザ出力があらかじめ設定した定常出力に達する
とレーザ出力を定常出力に保持して仮付溶接を続行し、
仮付溶接が鋼片の他方の側端近くまで進むとレーザ出力
を漸減し、仮付溶接を終了する。
(57) [Summary] [Object] To provide a method for joining hot-rolled steel slabs capable of eliminating burn-through during tack-welding and preventing breakage of the slabs in the rolling step following tack-welding. [Structure] The rear end surface of the high temperature preceding steel piece and the front end surface of the following steel piece are butted, and the butted portion is laser welded along this butted portion, and the temporarily tack welded steel piece is then welded. In the method of joining both steel pieces by pressing down in the thickness direction, the welding speed is kept constant, temporary welding is started from one side end of the steel pieces, and the side ends are temporarily attached while gradually increasing the laser output. When welding is performed and the laser output reaches a preset steady output, the laser output is maintained at the steady output and temporary welding is continued.
When the tack welding progresses to near the other side edge of the billet, the laser output is gradually reduced and the tack welding is completed.
Description
【０００１】[0001]
【産業上の利用分野】この発明は、シートバーやスラブ
などの熱間圧延鋼片の接合方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining hot rolled steel pieces such as a sheet bar and a slab.
【０００２】[0002]
【従来の技術】シートバーやスラブなどの鋼片の熱間圧
延では、先行鋼片の後端部と後行鋼片の前端部とを接合
することが行われている。これら鋼片は、厚みが２０〜
５０ mm 、幅が６００〜２０００ mm 程度である。ま
た、鋼片の温度は１０００℃前後である。この鋼片の接
合方法の一つとして、先行鋼片の後端面と後行鋼片の前
端面とを突き合わせ、突合せ部に沿って仮付溶接し、引
き続き仮付溶接部した鋼片を鋼片厚み方向に圧下して両
鋼片を接合する方法が周知である。また、仮付溶接にレ
ーザ溶接が用いられることも知られている。2. Description of the Related Art In the hot rolling of steel slabs such as sheet bars and slabs, the rear end of the preceding steel slab and the front end of the following steel slab are joined together. These steel pieces have a thickness of 20 to
The width is about 50 mm and the width is about 600 to 2000 mm. The temperature of the billet is around 1000 ° C. As one of the joining methods of this steel slab, the rear end face of the preceding steel slab and the front end face of the trailing steel slab are abutted, and temporary welding is performed along the abutting portion, and subsequently the steel slab subjected to the temporary welding is applied to the steel slab. A method is well known in which both steel pieces are joined by pressing down in the thickness direction. It is also known that laser welding is used for tack welding.
【０００３】レーザ溶接は、レンズまたは凹面鏡でレー
ザビームを集光してエネルギ密度を高くできる。このた
めに、集光照射部の鋼が瞬時に蒸発して鋼片表面にキー
ホールが発生する。レーザ溶接では、このキーホールを
溶接線に沿って移動し、鋼片を接合溶接する。このキー
ホールの移動によりキーホール周辺の鋼が溶融して溶融
プールが形成され、キーホールの移動によりその後方で
溶融プール中の溶融した鋼が凝固して溶接が完了する。
このキーホールの移動による溶融プールの長さは、レー
ザ出力と鋼片温度に比例し、移動速度（溶接速度）に逆
比例する。In laser welding, the energy density can be increased by focusing a laser beam with a lens or a concave mirror. For this reason, the steel in the focused irradiation portion is instantly evaporated, and a keyhole is generated on the surface of the billet. In laser welding, this keyhole is moved along a welding line to join and weld steel pieces. The movement of the keyhole melts the steel around the keyhole to form a molten pool, and the movement of the keyhole solidifies the molten steel in the molten pool behind the keyhole to complete welding.
The length of the molten pool due to the movement of the keyhole is proportional to the laser output and the billet temperature, and is inversely proportional to the moving speed (welding speed).
【０００４】[0004]
【発明が解決しようとする課題】図４は、鋼片を常温で
レーザ溶接した場合の熱履歴を示している。また、図５
は鋼片を熱間（１０００℃）でレーザ溶接した場合の熱
履歴を示している。なお、これら図において、ＴM は鋼
の溶融温度、ＴV は鋼の蒸発温度をそれぞれ示してい
る。常温でのレーザ溶接の場合、溶融・凝固時間は熱間
での場合に比べて数分の１と短いので、溶融した鋼の凝
固に必要な時間が短い。一方、熱間圧延工程中の鋼片は
高温（約１０００℃）であり、冷却効果が小さいために
図５に示すように溶融後の凝固に必要な時間が長く、そ
れに伴い溶融プールが長くなる。この結果、図６に示す
ように先行鋼片１と後行鋼片３との接合部６の側端部で
は溶融した鋼が溶融プールから鋼片側端に沿って流れ落
ち、溶落ち９が容易に発生する。FIG. 4 shows the heat history when a steel slab is laser-welded at room temperature. Also, FIG.
Shows the heat history when the steel pieces were laser welded hot (1000 ° C.). In these figures, T M indicates the melting temperature of steel and T V indicates the evaporation temperature of steel. In the case of laser welding at room temperature, the melting / solidifying time is a fraction of that in the case of hot welding, so that the time required for solidifying the molten steel is short. On the other hand, the billet during the hot rolling process has a high temperature (about 1000 ° C.), and the cooling effect is small, so that the time required for solidification after melting is long as shown in FIG. 5, and the molten pool becomes longer accordingly. . As a result, as shown in FIG. 6, at the side end of the joint 6 between the preceding steel piece 1 and the following steel piece 3, the molten steel flows down from the molten pool along the side edge of the steel piece, facilitating burn-through 9. appear.
【０００５】鋼片の突合せ部をレーザ溶接で仮付けする
場合、従来では図３に示すように、仮付溶接に際しレー
ザ出力を所定の出力に上昇させ、その出力を一定に保持
した状態で鋼片の一方の側端から他方の側端まで仮付溶
接していた。したがって、上述のように溶落ちが容易に
発生していた。In the case of temporarily attaching a butt portion of a steel slab by laser welding, conventionally, as shown in FIG. 3, the laser output is raised to a predetermined output during the temporary attachment welding, and the steel output is maintained constant. Temporary welding was performed from one side end of the piece to the other side end. Therefore, burn-through was easily generated as described above.
【０００６】図７（ａ）に示している曲線Ａは、圧下に
よるメタルフロー線を表している。圧延ロールは中高の
ロールクラウンが形成されているので、メタルフロー線
Ａは図に示すように山形となる。したがって、仮付溶接
およびその近傍は圧延ロールで圧下されると、図７
（ａ）に示すように鋼片中央部に圧縮応力が、また側端
部に引張応力が発生する。このために、接合部に溶落ち
があると、図７（ｂ）に示すように圧下により鋼片の側
端部に耳割れが生じ、さらには耳割れが成長して図７
（ｃ）に示すように接合部が破断することがあった。A curve A shown in FIG. 7 (a) represents a metal flow line due to reduction. Since the rolling roll has a medium-high roll crown, the metal flow line A has a chevron shape as shown in the figure. Therefore, when the tack welding and its vicinity are rolled down by the rolling rolls, as shown in FIG.
As shown in (a), compressive stress is generated in the central portion of the steel piece and tensile stress is generated in the side end portions. Therefore, if there is burn-through in the joint, as shown in FIG. 7 (b), the edge cracks occur at the side end of the steel slab due to the reduction, and further, the edge crack grows to cause the crack.
As shown in (c), the joint part was sometimes broken.
【０００７】この発明は、仮付溶接時の溶落ちをなく
し、仮付溶接に続くの圧延工程で鋼片の破断を防ぐこと
ができる熱間圧延鋼片の接合方法を提供しようとするも
のである。The present invention is intended to provide a method for joining hot-rolled steel slabs which can prevent burn-through during tack-welding and prevent breakage of the slabs in a rolling step following tack-welding. is there.
【０００８】[0008]
【課題を解決するための手段】第１の発明の熱間圧延鋼
片の接合方法は、高温の先行鋼片の後端面と後行鋼片の
前端面とを突き合わせ、この突合せ部に沿ってレーザ溶
接で突合せ部を仮付溶接し、引き続き仮付溶接した鋼片
を鋼片厚み方向に圧下して両鋼片を接合する方法におい
て、溶接速度を一定に保持し、鋼片の一方の側端から仮
付溶接を開始し、レーザ出力を漸増しながら側端部を仮
付溶接し、レーザ出力があらかじめ設定した定常出力に
達するとレーザ出力を定常出力に保持して仮付溶接を続
行し、仮付溶接が鋼片の他方の側端近くまで進むとレー
ザ出力を漸減し、仮付溶接を終了する。According to a first aspect of the present invention, there is provided a method for joining hot-rolled steel slabs in which a rear end surface of a high-temperature preceding steel slab and a front end surface of a trailing steel stake are butted together, Laser welding is used to temporarily tack weld the butt joints and then press down the tack welded steel pieces in the thickness direction of the steel pieces to join the two steel pieces together. Starting temporary welding from the end, temporary welding the side end while gradually increasing the laser output, and when the laser output reaches the preset steady output, the laser output is held at the steady output and the temporary welding continues. When the tack welding progresses to near the other side end of the billet, the laser output is gradually reduced and the tack welding is completed.
【０００９】レーザ出力の時間に対する増加率および減
少率は、熱間鋼片の厚みおよび温度、溶接速度、ならび
に定常出力などをパラメータとし、実機について実験に
より決める。たとえば、増加率および減少率は１０〜２
０ kW/s 程度である。鋼片側端部における溶接開始また
は終了時のレーザ出力は、定常出力の３０〜７０％であ
る。また、レーザ出力が漸増または漸減する鋼片側端部
における溶接長さは、１００〜２００ mm 程度である。The increase rate and the decrease rate of the laser output with respect to time are determined experimentally on an actual machine with parameters such as the thickness and temperature of the hot steel billet, the welding speed, and the steady output. For example, the rate of increase and decrease is 10-2
It is about 0 kW / s. The laser output at the start or end of welding at the end of the steel piece is 30 to 70% of the steady output. The welding length at the end of the steel piece where the laser output gradually increases or decreases is about 100 to 200 mm.
【００１０】第２の発明の熱間圧延鋼片の接合方法は、
高温の先行鋼片の後端面と後行鋼片の前端面とを突き合
わせ、この突合せ部に沿ってレーザビームで突合せ部を
仮付溶接し、引き続き仮付溶接した鋼片を鋼片厚み方向
に圧下して両鋼片を接合する方法において、レーザ出力
を一定に保持し、鋼片の一方の側端から仮付溶接を開始
し、溶接速度を徐々に減速しながら側端部を仮付溶接
し、溶接速度があらかじめ設定した定常速度に達すると
溶接速度を定常速度に保持して仮付溶接を続行し、仮付
溶接が鋼片の他方の側端近くまで進むと溶接速度を徐々
に加速し、仮付溶接を終了する。A method for joining hot-rolled steel pieces according to the second invention is
The rear end surface of the high temperature preceding steel slab and the front end surface of the trailing steel slab are abutted together, and the butt portion is temporarily welded with the laser beam along this abutting portion, and subsequently the temporarily welded steel slab is welded in the thickness direction of the slab. In the method of joining both steel pieces by pressing down, the laser output is kept constant, temporary welding is started from one side end of the steel pieces, and the side ends are temporarily welded while gradually reducing the welding speed. Then, when the welding speed reaches the preset steady speed, the welding speed is maintained at the steady speed and the tack welding is continued, and when the tack welding progresses near the other side edge of the billet, the welding speed is gradually accelerated. Then, tack welding is completed.
【００１１】溶接速度の減速度および加速度は、熱間鋼
片の厚みおよび温度、レーザ出力、ならびに定常速度な
どをパラメータとし、実機について実験により決める。
たとえば、減速度および加速度は０．１〜０．３ m/s2
程度である。鋼片側端部における溶接開始または終了時
の溶接速度は、定常速度の０．５〜１．０倍程度であ
る。また、溶接速度が漸増または漸減する鋼片側端部に
おける溶接長さは、第１の発明と同様に１００〜２００
mm 程度である。The deceleration and the acceleration of the welding speed are determined by an experiment on an actual machine with parameters such as the thickness and temperature of the hot steel billet, the laser output, and the steady speed.
For example, deceleration and acceleration are 0.1-0.3 m / s 2
It is a degree. The welding speed at the start or end of welding at the steel piece side end is about 0.5 to 1.0 times the steady speed. Further, the welding length at the steel piece side end where the welding speed gradually increases or decreases is 100 to 200 as in the first invention.
It is about mm.
【００１２】[0012]
【作用】第１の発明では、鋼片の側端部でレーザ出力が
漸増または漸減されるので、側端部では鋼片中央部での
レーザ出力（定常出力）よりも低い出力で溶接される。
したがって、キーホールの深さは鋼片側面に近付くほど
浅くなりので、溶融プールの大きさも鋼片側面に近付く
ほど徐々に小さくなる。この結果、鋼片の側端面から溶
融金属が流れ落ちることはなく、溶落ちは発生しない。In the first aspect of the invention, since the laser output is gradually increased or decreased at the side end of the steel slab, the side end is welded at a power lower than the laser output (steady output) at the center of the steel slab. .
Therefore, since the depth of the keyhole becomes shallower as it approaches the side surface of the steel piece, the size of the molten pool also gradually decreases as it approaches the side surface of the steel piece. As a result, the molten metal does not flow down from the side end surface of the steel slab, and burn-through does not occur.
【００１３】第２の発明では、鋼片の側端部で一定の溶
接速度から徐々に減速または加速されるので、側端部で
は鋼片中央部よりもレーザビーム照射時間は短くなる。
つまり、側端部に供給される単位面積当たりのレーザビ
ームのエネルギは、鋼片中央部よりも小さい。したがっ
て、第１の発明と同様に、鋼片の側端面から溶融金属が
流れ落ちることはなく、溶落ちは発生しない。In the second aspect of the invention, since the welding speed is gradually decelerated or accelerated from the constant welding speed at the side end portion of the steel piece, the laser beam irradiation time at the side end portion is shorter than that at the central portion of the steel piece.
That is, the energy of the laser beam per unit area supplied to the side end portion is smaller than that in the central portion of the billet. Therefore, similarly to the first aspect, the molten metal does not flow down from the side end surface of the steel slab, and the burn-through does not occur.
【００１４】[0014]
【実施例】熱間圧延シートバーの接合を例として、第１
の発明の実施例を説明する。図８は熱間圧延設備に設け
られたシートバー接合設備の概略側面図であり、図９は
同設備の平面図である。[Example] The first example of joining hot-rolled sheet bars
An embodiment of the invention will be described. FIG. 8 is a schematic side view of the sheet bar joining equipment provided in the hot rolling equipment, and FIG. 9 is a plan view of the equipment.
【００１５】シートバー１、３の先端部および後端部は
走間シャー１１でバー幅方向に沿って切り落とされ、接
合面が形成される。シートバー１、３は、長さが２０m
、幅が１１００ mm 、厚みは３３ mm である。また、
シートバー１、３の温度は１０００℃である。シートバ
ー１、３の送り速度は、８０m/min である。The front and rear ends of the seat bars 1 and 3 are cut off along the bar width direction by the running shear 11 to form joint surfaces. Seat bars 1 and 3 are 20m long
, The width is 1100 mm and the thickness is 33 mm. Also,
The temperature of the sheet bars 1 and 3 is 1000 ° C. The feed speed of the sheet bars 1 and 3 is 80 m / min.
【００１６】ついで、先行シートバー１の後端面と後行
シートバー３の前端面とを突き合わせ、この突合せ部５
に沿ってレーザ溶接で突合せ部５を仮付溶接７する。レ
ーザはＣＯ2 レーザであり、定常出力は４５ kW であ
る。レーザ発振器１３は固定されているが、溶接ヘッド
１５はシートバー１、３とともに移動する。レーザビー
ム伝送光学系１４を介してレーザ発振器１３から移動す
る溶接ヘッド１５にレーザビームが伝送される。溶接ヘ
ッド１５は伝送されてきたレーザビームを所要のスポッ
ト径に集光する。溶接速度は１０ m/minであり、ビード
幅は３．０ mm である。仮付溶接は、レーザ出力を２０
kW/s で漸増し、２５ kW になると、シートバー１、３
の一方の側端から仮付溶接を開始する。仮付溶接開始後
は、レーザ出力が４５ kW に達するとレーザ出力を４５
kW に保持して仮付溶接を続行する。レーザ出力が４５
kW に達した時点で、溶接長さは約１７０ mm である。
仮付溶接がシートバー１、３の他方の側端手前約１７０
mm に達すると、レーザ出力を２０ kW/s で漸減し、仮
付溶接を終了する。図１は、上記仮付溶接のレーザ出力
の経時変化を示している。Next, the rear end face of the preceding seat bar 1 and the front end face of the following seat bar 3 are butted against each other, and the butted portion 5 is formed.
The butt portion 5 is temporarily welded 7 by laser welding. The laser is a CO 2 laser and the steady output is 45 kW. The laser oscillator 13 is fixed, but the welding head 15 moves together with the seat bars 1 and 3. The laser beam is transmitted from the laser oscillator 13 to the welding head 15 that moves via the laser beam transmission optical system 14. The welding head 15 focuses the transmitted laser beam on a required spot diameter. The welding speed is 10 m / min and the bead width is 3.0 mm. For temporary welding, laser output is 20
It gradually increases at kW / s, and when it reaches 25 kW, seat bars 1, 3
The tack welding is started from one side end. After the start of tack welding, when the laser output reaches 45 kW, the laser output is changed to 45
Hold at kW and continue tack welding. Laser output is 45
When reaching kW, the weld length is about 170 mm.
Temporary welding is about 170 before the other side edge of the seat bars 1 and 3.
When it reaches mm, the laser output is gradually reduced at 20 kW / s, and tack welding is completed. FIG. 1 shows the change over time in the laser output of the tack welding.
【００１７】仮付溶接に引き続いて仕上圧延機列１６
で、圧延ロール１７により仮付溶接したシートバー１、
３を、シートバー厚み方向に圧下して両シートバー１、
３を接合する。圧下率は、３０％である。Subsequent to tack welding, the finishing rolling mill train 16
Then, the sheet bar 1 temporarily tack-welded by the rolling rolls 17,
3 in the thickness direction of the seat bar by pressing both seat bars 1,
Join 3 The rolling reduction is 30%.
【００１８】上記方法でシートバーを１００回接合した
結果、溶落ちは発生せず、接合部が破断することもなか
った。As a result of joining the sheet bars 100 times by the above-mentioned method, no burn-through occurred and the joined portion did not break.
【００１９】一方、上記と同じシートバーを同じ接合設
備で従来法により接合した。図３に示すように、レーザ
出力を４５ kW 一定として仮付溶接を行った。この結
果、シートバーを１００回接合した結果、９０回溶落ち
が発生した。溶落ちが発生したものはすべて、圧延によ
り接合部が破断した。On the other hand, the same sheet bars as above were joined by the conventional method using the same joining equipment. As shown in FIG. 3, tack welding was performed with the laser output kept constant at 45 kW. As a result, the burnout occurred 90 times as a result of joining the sheet bars 100 times. In all of the burn-through products, the joints were broken by rolling.
【００２０】つぎに、第２の発明の実施例について説明
する。シートバー接合設備、および熱間圧延設備は、上
記実施例の設備と同じである。また、シートバーの寸法
および温度も上記実施例のものと同じである。Next, an embodiment of the second invention will be described. The sheet bar joining equipment and the hot rolling equipment are the same as the equipment of the above-mentioned embodiment. The size and temperature of the seat bar are also the same as those in the above embodiment.
【００２１】レーザ出力は、４５ kW 一定に保持する。
あらかじめ設定した溶接速度（５ m/min）で一方の側端
から仮付溶接を開始し、減速度（０．１ m/s2 ）で減速
しながらシートバー１、３の側端部を仮付溶接する。溶
接速度があらかじめ設定した定常速度（１０ m/min）に
達すると溶接速度を定常速度に保持して仮付溶接を続行
する。溶接速度が定常速度に達した時点で、溶接長さは
約１７０ mm である。そして、仮付溶接が他方の側端手
前約１７０ mm に達すると、溶接速度を加速度（０．１
m/s2 ）で加速し、仮付溶接を終了する。ビード幅は
３．０ mm である。The laser power is kept constant at 45 kW.
Temporary welding is started from one side edge at a preset welding speed (5 m / min), and the side edges of the seat bars 1 and 3 are temporarily reduced while decelerating at a deceleration rate (0.1 m / s 2 ). Welding. When the welding speed reaches a preset steady speed (10 m / min), the welding speed is maintained at the steady speed and the tack welding is continued. When the welding speed reaches the steady speed, the welding length is about 170 mm. When the tack welding reaches about 170 mm before the other side edge, the welding speed is accelerated (0.1 mm).
Accelerate at m / s 2 ) and finish tack welding. The bead width is 3.0 mm.
【００２２】仮付溶接に引き続いて仕上圧延機列１６
で、圧延ロール１７により仮付溶接したシートバーを、
シートバー厚み方向に圧下して両シートバー１、３を接
合する。圧下率は、３０％である。Subsequent to tack welding, the finish rolling mill train 16
Then, the sheet bar temporarily welded by the rolling roll 17 is
The sheet bars 1 and 3 are joined by pressing down the sheet bar in the thickness direction. The rolling reduction is 30%.
【００２３】上記方法でシートバーを１００回接合した
結果、溶落ちは発生せず、接合部が破断することもなか
った。As a result of joining the sheet bars 100 times by the above-mentioned method, no burn-through occurred and the joined portion did not break.
【００２４】[0024]
【発明の効果】この発明では、鋼片の側端部でレーザ出
力が漸増もしくは漸減される、または溶接速度が徐々に
減速もしくは加速される。したがって、側端部に供給さ
れる単位面積当たりのレーザビームのエネルギは漸減
し、溶融プールの大きさは小さくなる。この結果、溶落
ちは発生せず、また圧延時に先行鋼片と後行鋼片との接
合部が破断することもない。According to the present invention, the laser output is gradually increased or decreased at the side end portion of the steel piece, or the welding speed is gradually decreased or accelerated. Therefore, the energy of the laser beam per unit area supplied to the side end portion is gradually reduced, and the size of the molten pool is reduced. As a result, burn-through does not occur and the joint between the preceding steel piece and the following steel piece does not break during rolling.
【図１】第１の発明の方法において、仮付溶接のレーザ
出力の経時変化を示す線図である。FIG. 1 is a diagram showing a temporal change in laser output in tack welding in the method of the first invention.
【図２】第２の発明の方法において、仮付溶接の溶接速
度の経時変化を示す線図である。FIG. 2 is a diagram showing a temporal change in welding speed of tack welding in the method of the second invention.
【図３】従来法において、仮付溶接のレーザ出力の経時
変化を示す線図である。FIG. 3 is a diagram showing a temporal change in laser output of tack welding in the conventional method.
【図４】鋼片を常温でレーザ溶接した場合の熱履歴を示
す線図である。FIG. 4 is a diagram showing a heat history when a steel piece is laser-welded at room temperature.
【図５】鋼片を熱間（１０００℃）でレーザ溶接した場
合の熱履歴を示す線図である。FIG. 5 is a diagram showing a heat history when a steel piece is hot-welded (1000 ° C.) by laser welding.
【図６】溶落ちを模式的に示す斜視図である。FIG. 6 is a perspective view schematically showing burn-through.
【図７】鋼片接合部の破断発生機構を説明する図面であ
る。FIG. 7 is a diagram illustrating a fracture occurrence mechanism of a steel slab joint.
【図８】この発明の方法を実施する鋼片接合設備の一例
を示す概略側面図である。FIG. 8 is a schematic side view showing an example of a steel piece joining facility for carrying out the method of the present invention.
【図９】図７に示す設備の平面図である。9 is a plan view of the equipment shown in FIG. 7. FIG.
１ 先行鋼片 ３ 後行鋼片 ５ 突合せ部 ７ 仮付溶接 ９ 溶落ち １１ 走間シャー １３ レーザ発振器 １５ 溶接ヘッド １６ 仕上圧延機列 １７ 圧延ロール DESCRIPTION OF SYMBOLS 1 Leading steel piece 3 Trailing steel piece 5 Butt portion 7 Temporary welding 9 Burn-through 11 Tracing shear 13 Laser oscillator 15 Welding head 16 Finishing mill row 17 Rolling roll
Claims (2)
端面とを突き合わせ、この突合せ部に沿ってレーザ溶接
で突合せ部を仮付溶接し、引き続き仮付溶接した鋼片を
鋼片厚み方向に圧下して両鋼片を接合する方法におい
て、溶接速度を一定に保持し、鋼片の一方の側端から仮
付溶接を開始し、レーザ出力を漸増しながら側端部を仮
付溶接し、レーザ出力があらかじめ設定した定常出力に
達するとレーザ出力を定常出力に保持して仮付溶接を続
行し、仮付溶接が鋼片の他方の側端近くまで進むとレー
ザ出力を漸減し、仮付溶接を終了することを特徴とする
熱間圧延鋼片の接合方法。1. A high-temperature preceding steel slab rear end face and a trailing steel slab front end face are abutted against each other, laser welding is performed along the abutting portion to temporarily weld the abutting portion, and then the temporarily welded steel piece is welded. In the method of joining both steel pieces by pressing down in the thickness direction of the steel pieces, the welding speed is kept constant, temporary welding is started from one side end of the steel pieces, and the side end portions are gradually increased while gradually increasing the laser output. When tack welding is performed and the laser output reaches the preset steady output, the laser output is maintained at the steady output and the tack welding is continued.When the tack welding progresses near the other side edge of the steel piece, the laser output is A method for joining hot-rolled steel slabs, characterized by gradually reducing and terminating tack welding.
端面とを突き合わせ、この突合せ部に沿ってレーザビー
ムで突合せ部を仮付溶接し、引き続き仮付溶接した鋼片
を鋼片厚み方向に圧下して両鋼片を接合する方法におい
て、レーザ出力を一定に保持し、鋼片の一方の側端から
仮付溶接を開始し、溶接速度を徐々に減速しながら側端
部を仮付溶接し、溶接速度があらかじめ設定した定常速
度に達すると溶接速度を定常速度に保持して仮付溶接を
続行し、仮付溶接が鋼片の他方の側端近くまで進むと溶
接速度を徐々に加速し、仮付溶接を終了することを特徴
とする熱間圧延鋼片の接合方法。2. The hot end of the preceding steel piece and the trailing end surface of the trailing steel piece are butted against each other, and the butted portion was tack welded along the butted portion with a laser beam. In the method of joining both steel pieces by pressing down in the thickness direction of the steel pieces, the laser output is kept constant, temporary welding is started from one side edge of the steel pieces, and the side edges are gradually reduced while gradually reducing the welding speed. Part is tack welded, and when the welding speed reaches a preset steady speed, the welding speed is maintained at a steady speed and the tack welding is continued, and when the tack welding progresses near the other side edge of the steel piece, welding is performed. A method for joining hot-rolled steel slabs, characterized by accelerating speed gradually and ending tack welding.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7061160A JPH08257775A (en) | 1995-03-20 | 1995-03-20 | Joining method for hot rolled billets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7061160A JPH08257775A (en) | 1995-03-20 | 1995-03-20 | Joining method for hot rolled billets |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08257775A true JPH08257775A (en) | 1996-10-08 |
Family
ID=13163120
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7061160A Pending JPH08257775A (en) | 1995-03-20 | 1995-03-20 | Joining method for hot rolled billets |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08257775A (en) |
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|---|---|---|---|---|
| WO2015097027A1 (en) * | 2013-12-23 | 2015-07-02 | Kuka Roboter Gmbh | Welding robot and method for operating a laser welding device |
| EP3216552A1 (en) * | 2016-03-09 | 2017-09-13 | NGK Spark Plug Co., Ltd. | Laser welding methods, method of manufacturing a welded body, method of manufacturing electrode for spark plug, and method of manufacturing spark plug based on such laser welding methods |
| CN107813094A (en) * | 2017-11-03 | 2018-03-20 | 河南卫华机械工程研究院有限公司 | A kind of flexible member assembles device |
| CN109048052A (en) * | 2018-08-09 | 2018-12-21 | 江苏大学 | A kind of scan method inhibiting the deformation of laser welding thin plate bending |
| CN110430965A (en) * | 2017-03-27 | 2019-11-08 | 三菱电机株式会社 | laser welding method |
-
1995
- 1995-03-20 JP JP7061160A patent/JPH08257775A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015097027A1 (en) * | 2013-12-23 | 2015-07-02 | Kuka Roboter Gmbh | Welding robot and method for operating a laser welding device |
| EP3216552A1 (en) * | 2016-03-09 | 2017-09-13 | NGK Spark Plug Co., Ltd. | Laser welding methods, method of manufacturing a welded body, method of manufacturing electrode for spark plug, and method of manufacturing spark plug based on such laser welding methods |
| US10201876B2 (en) | 2016-03-09 | 2019-02-12 | Ngk Spark Plug Co., Ltd. | Laser welding method, method for manufacturing welded body, method for manufacturing electrode for spark plug, and method for manufacturing spark plug |
| CN110430965A (en) * | 2017-03-27 | 2019-11-08 | 三菱电机株式会社 | laser welding method |
| CN110430965B (en) * | 2017-03-27 | 2021-02-02 | 三菱电机株式会社 | Laser welding method |
| CN107813094A (en) * | 2017-11-03 | 2018-03-20 | 河南卫华机械工程研究院有限公司 | A kind of flexible member assembles device |
| CN107813094B (en) * | 2017-11-03 | 2019-12-03 | 河南卫华重型机械股份有限公司 | A kind of flexible member assembly device |
| CN109048052A (en) * | 2018-08-09 | 2018-12-21 | 江苏大学 | A kind of scan method inhibiting the deformation of laser welding thin plate bending |
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