JPH0694069B2 - One-sided welding method for pipes - Google Patents
One-sided welding method for pipesInfo
- Publication number
- JPH0694069B2 JPH0694069B2 JP33037890A JP33037890A JPH0694069B2 JP H0694069 B2 JPH0694069 B2 JP H0694069B2 JP 33037890 A JP33037890 A JP 33037890A JP 33037890 A JP33037890 A JP 33037890A JP H0694069 B2 JPH0694069 B2 JP H0694069B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- arc
- groove
- pipe
- speed
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
Links
- 238000003466 welding Methods 0.000 title claims description 61
- 238000000034 method Methods 0.000 title claims description 26
- 239000000463 material Substances 0.000 claims description 15
- 239000000919 ceramic Substances 0.000 claims description 9
- 239000011324 bead Substances 0.000 description 10
- 238000010586 diagram Methods 0.000 description 5
- 230000035515 penetration Effects 0.000 description 4
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 3
- 229910052802 copper Inorganic materials 0.000 description 3
- 239000010949 copper Substances 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000010355 oscillation Effects 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
Landscapes
- Arc Welding In General (AREA)
- Butt Welding And Welding Of Specific Article (AREA)
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、パイプの片面溶接方法に関する。TECHNICAL FIELD The present invention relates to a single-sided welding method for pipes.
［従来の技術］ 従来のパイプの片面溶接方法にはスプレッド工法のよう
に100継手／日のパイプを溶接するような高速溶接用の
ものと、１〜２継手／日の低速溶接用に分けられる。従
来のパイプの高速溶接用の片面溶接方法ではパイプの端
面に環状溝の底部がＶ形、又はＵ形となる形状の狭開先
を形成し、パイプの内面側に銅製の裏当材を配し、自動
溶接機をパイプ外面に取り付けた円周ガイドレール上を
走行させながらアークの揺動速度を5Hz以下、アークの
揺動幅を1.0〜2.0mmとした揺動アークによるMAG溶接法
により溶接電流250〜300A、溶接速度75〜110cm/分の条
件でパイプの外面から初層片面溶接する方法が知られて
いる。[Prior Art] Conventional one-sided pipe welding methods are divided into those for high-speed welding such as welding 100 joints / day like the spread method and those for low-speed welding 1-2 joints / day. . In the conventional single-sided welding method for high-speed welding of pipes, a narrow groove with a V-shaped or U-shaped bottom of the annular groove is formed on the end surface of the pipe, and a copper backing material is placed on the inner surface side of the pipe. Then, welding is performed by the MAG welding method using an oscillating arc with an arc oscillating speed of 5 Hz or less and an arc oscillating width of 1.0 to 2.0 mm while traveling on a circumferential guide rail with an automatic welding machine attached to the outer surface of the pipe. A method is known in which the first layer is single-sided welded from the outer surface of the pipe under the conditions of a current of 250 to 300 A and a welding speed of 75 to 110 cm / min.
［発明が解決しようとする課題］ 従来のパイプの片面溶接方法では溶接電流を増大させ溶
接速度を高めた高速溶接を行うと溶接ビードが不連続に
なり溶接部分に溶込不足や割れなどの溶接欠陥が発生す
るという問題点があった。また、開先ならいを行なう方
法では、開先内にガイドローラを接触走行させる接触式
センサにより、開先幅ならいを行なう方法があるが、精
度的に問題があって、高速溶接には実用化されていない
のが現状である。[Problems to be Solved by the Invention] In the conventional one-sided pipe welding method, when high-speed welding is performed by increasing the welding current to increase the welding speed, the welding bead becomes discontinuous and welding such as insufficient penetration or cracking in the welded portion There is a problem that defects occur. In addition, in the method of grooving, there is a method of grooving with a contact type sensor that causes a guide roller to travel in contact with the groove. The current situation is that it has not been done.
本発明はかかる問題点を解決するためになされたもので
パイプの突合せ溶接における初層溶接を安定な品質で高
速化できかつ、アークセンサによる高精度開先自動なら
いの適用が可能なパイプの片面溶接方法を得ることを目
的とするものである。The present invention has been made to solve the above problems, and it is possible to speed up the first layer welding in butt welding of pipes with stable quality and to apply one side of a pipe with high precision automatic groove tracing by an arc sensor. The purpose is to obtain a welding method.
［課題を解決するための手段］ 本発明に係るパイプの片面溶接方法は、パイプの突合せ
端面に環状溝の底部がＶ形となる形状の狭開先又はＶ開
先を形成し、パイプ内面側にセラミックス製の裏当材を
配し、自動溶接機をパイプ外面に取り付けた円周ガイド
レール上を走行させながら、アークの回転速度を10Hz以
上、アークの回転直径を1.0〜4.0mmとした高速回転アー
クによるガスシールドアーク溶接法によりアークセンサ
による開先自動倣い制御を行ないながら、ワイヤ径0.8
〜1.6mmでパイプの外面から全姿勢で片面溶接すること
に特徴を有するものである。[Means for Solving the Problems] A method for single-sided welding of a pipe according to the present invention is to form a narrow groove or a V-shaped groove having a V-shaped bottom of an annular groove on a butt end surface of the pipe, and to form an inner surface of the pipe. A ceramic backing material is placed on the inner surface of the pipe, and while the automatic welding machine is running on a circumferential guide rail attached to the outer surface of the pipe, the arc rotation speed is 10 Hz or more, and the arc rotation diameter is 1.0 to 4.0 mm. The diameter of the wire is 0.8 while controlling the groove automatically by the arc sensor by the gas shield arc welding method using the rotating arc.
It is characterized by being welded on one side in all positions from the outer surface of the pipe at ~ 1.6 mm.
この発明においてアークを高速で回転させる高速回転ア
ーク溶接法を用いる理由は従来法の揺動回数が5Hz以下
に比べて10Hz以上（実験的にはMAX250Hz）の高速（回
転）揺動が得られるので高速溶接を行っても揺動ピッチ
が粗いために生ずる溶込ムラやビード形状不良が発生し
ない。すなわち高速溶接でビードが不連続となる高速限
界が従来の溶接方法と比べると本法の方が1.4〜2.0倍高
速側にある。又、初層片面溶接の特に高速溶接では溶接
トーチつまりアークの開先ならい精度、応答速度が溶接
品質を大きく左右するが本法では円運動するアーク自身
とセンサとすることによりリアルタイムで高精度の開先
ならい制御ができる。The reason for using the high-speed rotating arc welding method in which the arc is rotated at a high speed in this invention is that a high-speed (rotation) oscillation of 10 Hz or more (experimentally MAX250 Hz) can be obtained as compared with the oscillation frequency of 5 Hz or less in the conventional method. Even if high-speed welding is performed, uneven penetration and defective bead shape caused by a coarse swing pitch do not occur. In other words, the high speed limit at which the bead becomes discontinuous during high speed welding is 1.4 to 2.0 times faster than the conventional welding method. Also, in the case of high speed welding of the first layer, especially in high speed welding, the welding torch, that is, the accuracy of the groove groove and the response speed greatly affect the welding quality.However, in this method, the arc itself that moves circularly and the sensor provide high accuracy in real time. You can control the groove.
一方、セラミックス製裏当材を用いる理由は、従来法の
銅裏当金では溶接直後の溶融池が急冷されるために溶接
部に割れが発生しやすいため、この面からも溶接の高速
化に限界のあることを見出した為であり、セラミックス
製裏当材を用いると銅裏当材と比較してはるかに高速化
できる。On the other hand, the reason why the ceramic backing material is used is that with the conventional copper backing metal, the weld pool immediately after welding is rapidly cooled and cracks easily occur in the welded part. This is because it has been found that there is a limit, and the use of a ceramic backing material can result in much higher speed than a copper backing material.
［作用］ 本発明によれば、高速回転アーク溶接法とパイプ内面側
にセラミックス製の裏当材を使用しているため、従来の
揺動アーク法に比べ1.4〜2.0倍の高速溶接でもワイヤ径
0.8〜1.6mmで安定した溶込みと良好な溶接ビードが得ら
れる。[Operation] According to the present invention, since the high speed rotating arc welding method and the ceramic backing material are used on the inner surface of the pipe, the wire diameter can be 1.4 to 2.0 times faster than the conventional swing arc method.
A stable penetration and a good weld bead can be obtained at 0.8 to 1.6 mm.
又、アークセンサによる開先ならい制御によりリアルタ
イムに高精度のならいができるので溶接作業が自動化さ
れ安定した裏ビード形状と良好な表ビード形状が実現さ
れる。In addition, since the groove profile control by the arc sensor enables highly accurate profile in real time, the welding operation is automated and a stable back bead shape and a good front bead shape are realized.
［実施例］ 以下に図面を用いて本発明の溶接方法を説明する。[Example] The welding method of the present invention will be described below with reference to the drawings.
第１図は自動溶接機の概略構成図であり、溶接機本体１
はパイプ10の外面に仮付けされた円周ガイドレール12に
沿って自走するように設置されている。この溶接機本体
１に設けられる溶接トーチ２はモータ３により歯車機構
４を介して回転せしめられるとともに、開先14の幅方向
（ｘ軸）に移動可能なｘ軸スライドブロック５とトーチ
軸方向（ｙ軸）に移動可能なｙ軸スライドブロック６を
介して支持されている。トーチ２の回転数Ｎがアークの
回転数であり、回転速度や回転位置は図示しない回転検
出器により検出される。溶接ワイヤ７はトーチ２の偏心
孔を有する通電チップに自動送給されるようになってお
り、この偏心距離によってアークの回転直径Ｄが定ま
る。これにより回転アーク法を実施することができる。FIG. 1 is a schematic configuration diagram of an automatic welding machine.
Is installed so as to be self-propelled along a circumferential guide rail 12 temporarily attached to the outer surface of the pipe 10. The welding torch 2 provided in the main body 1 of the welding machine is rotated by the motor 3 via the gear mechanism 4, and the x-axis slide block 5 and the torch axial direction (movable in the width direction of the groove 14 (x-axis)). It is supported via a y-axis slide block 6 that is movable in the y-axis). The rotation speed N of the torch 2 is the rotation speed of the arc, and the rotation speed and rotation position are detected by a rotation detector (not shown). The welding wire 7 is automatically fed to the current-carrying tip having the eccentric hole of the torch 2, and the eccentric distance determines the rotating diameter D of the arc. This allows the rotating arc method to be implemented.
16は開先14に対向して配されたセラミックス製の裏当材
である。Reference numeral 16 is a ceramic backing material that is arranged so as to face the groove 14.
第２図は高速回転アークの原理図であり、電極ノズル21
は軸受部20で回転自在に支持され、22は電極ノズル21の
下部にネジ接合され、偏心したワイヤ通過孔を有する通
電チップ、７は溶接ワイヤで、電極ノズルの中心孔を通
り通電チップ22の偏心孔から連続送給される。３はモー
タで、電極ノズル21を歯車機構を介して１方向に連続回
転させる、つまり電極ノズル21の先端に接合した偏心孔
を有する通電チップ22も、回転されるので通電チップ22
の先端から送給される溶接ワイヤ７も円運動しアークが
容易に且つ高速で回転できるものである。Fig. 2 shows the principle of the high-speed rotating arc.
Is rotatably supported by a bearing portion 20, 22 is a current-carrying tip having an eccentric wire passage hole, which is screwed to the lower portion of the electrode nozzle 21, and 7 is a welding wire, which passes through the center hole of the electrode nozzle and is It is continuously fed from the eccentric hole. 3 is a motor for continuously rotating the electrode nozzle 21 in one direction via the gear mechanism, that is, the current-carrying tip 22 having an eccentric hole joined to the tip of the electrode nozzle 21 is also rotated, so that the current-carrying tip 22
The welding wire 7 fed from the tip of the arc also makes a circular motion and the arc can be easily rotated at high speed.
第３図はアークセンサによる開先ならい制御の原理図
で、回転する溶接ワイヤ７すなわちアークの位置に対応
して変化するアーク電圧Ｅの波形を示す。図中、（ａ）
はアークの位置を定義したもので右方向に連続回転する
アークの前方の中央をＣｆ、後方の中央をＣｒ、左・右
をＬ・Ｒとした。図において実線で示した波形は図中
（ｂ）のように回転アークの中心が開先中心よりΔＸだ
けＲ側にずれている場合、破線で示した波形はずれてい
ない場合を示す。破線のようにずれていない場合は位置
Ｃｆに対して左右対称であるが、実線のようにΔＸだけ
ずれている場合は波形は非対称となる。この波形の非対
称を検出し、修正することによりＸ軸方向のずれ量ΔＸ
を修正することができる。すなわち波形を位置Ｃｆ点を
中心として左右、所定角の間でけ取り出し、所定角間で
作る波形面積ＳＬ,SＲを求めて、この面積ＳＬ,SＲが等
しくなるように溶接トーチをＸ軸方向に修正することに
より、アークの回転軸心と開先中心を一致させることが
できる。FIG. 3 is a principle diagram of the groove profile control by the arc sensor, and shows the waveform of the arc voltage E which changes corresponding to the position of the rotating welding wire 7, that is, the arc. In the figure, (a)
Defines the position of the arc, where the front center of the arc that continuously rotates to the right is C f , the rear center is C r , and the left and right are L and R. In the figure, the waveform shown by the solid line shows the case where the center of the rotating arc deviates from the groove center to the R side by ΔX as shown in (b) in the figure, and the waveform shown by the broken line does not deviate. The waveform is asymmetric with respect to the position C f when it is not displaced as shown by the broken line, but the waveform is asymmetric when it is displaced by ΔX as shown by the solid line. By detecting and correcting the asymmetry of this waveform, the deviation amount ΔX in the X-axis direction
Can be modified. That is, the waveform is picked out between the left and right predetermined angles around the position C f , the waveform areas S L and S R created between the predetermined angles are obtained, and the welding torch is set so that the areas S L and S R become equal. By correcting in the X-axis direction, the axis of rotation of the arc and the groove center can be matched.
またトーチの高さ方向、すなわちｙ軸方向の距離制御は
溶接電流波形の一回転分の平均値と、基準値を比較し、
差が零になるようにｙ軸を移動制御する方式である。Further, in the height direction of the torch, that is, the distance control in the y-axis direction, the average value for one rotation of the welding current waveform is compared with the reference value,
In this method, the y-axis is moved and controlled so that the difference becomes zero.
第４図（ａ），（ｂ），（ｃ）は開先形状と裏当材の拡
大断面図で、図において突合されたパイプ10の開先14の
形状は底部14aがＶ形を有する環状溝14bで、その縦壁の
傾斜角度θは０゜〜３゜に形成されている。また、底部
14aの傾斜角度αは70゜〜110゜である。更に、RF寸法は
0.5〜1.5mm、パイプの肉厚Ｔが８〜16.7mmのものにおい
て、環状溝14bの溝幅Ｇは５〜10mmに形成されている。
なお、開先14の平板内面側第４図（ｂ）に示すように小
さな内面開先14cを設けてもよく、その内面開先14cの傾
斜角度βは70〜110゜であり、内面開先14cの高さ寸法は
0.5〜1.5mmである。第４図（ｃ）に示すものは突合され
たパイプ10の開先14の形状がＶ形のもので、その開先14
の開先角度γは30゜〜110゜である。16はパイプ10の開
先14の裏面側に配されたセラミックス製の裏当材であ
る。なお、第６図（ａ），（ｂ）に示す溝付のセラミッ
クス製の裏当材16a又は16b等も用いる。4 (a), (b), and (c) are enlarged cross-sectional views of the groove shape and the backing material, and the groove 14 of the pipe 10 abutted in the figure has an annular shape in which the bottom 14a has a V shape. In the groove 14b, the vertical wall has an inclination angle θ of 0 ° to 3 °. Also the bottom
The inclination angle α of 14a is 70 ° to 110 °. Furthermore, the RF dimension is
When the pipe wall thickness T is 0.5 to 1.5 mm and the pipe thickness T is 8 to 16.7 mm, the groove width G of the annular groove 14b is formed to be 5 to 10 mm.
A small inner surface groove 14c may be provided as shown in FIG. 4 (b) on the flat plate inner surface side of the groove 14, and the inclination angle β of the inner surface groove 14c is 70 to 110 °. The height of 14c is
It is 0.5 to 1.5 mm. In FIG. 4 (c), the shape of the groove 14 of the butted pipes 10 is V-shaped, and the groove 14 is formed.
The groove angle γ is 30 ° to 110 °. Reference numeral 16 is a ceramic backing material arranged on the back surface side of the groove 14 of the pipe 10. The grooved ceramic backing material 16a or 16b shown in FIGS. 6 (a) and 6 (b) is also used.
第５図は溶接されたビードの断面の積層状態を示す。図
において初層Ｒは良好な裏ビード形成が得られる。溶込
不足や割れなどの溶接欠陥も生じなかった。積層Ｆ、仕
上層Ｃの溶接も本発明による溶接方法で大電流、高速度
で施工できる。FIG. 5 shows the laminated state of the cross section of the welded beads. In the figure, a good back bead formation is obtained for the first layer R. Weld defects such as insufficient penetration and cracks did not occur. The welding of the laminated layer F and the finishing layer C can be performed with a large current and a high speed by the welding method according to the present invention.
上述した具体例ではCO2ガス100％の雰囲気で溶接を行っ
ているが、不活性ガス80％との混合ガスの雰囲気で溶接
を行っても同様に実施しうることは言うまでもない。Although welding is performed in the atmosphere of 100% CO 2 gas in the above-described specific example, it goes without saying that welding can be performed in the same manner even in a mixed gas atmosphere of 80% inert gas.
［発明の効果］ 本発明は以上説明したように高速回転アーク溶接法とア
ークセンサ自動開先ならい制御とさらに、開先裏面にセ
ラミックス製の裏当材を使用することとにより、大電
流、高速溶接でパイプの外面から片面溶接を全姿勢で行
ってパイプの突合せ溶接を高品質、高能率で実施でき、
さらに高品質で良好な裏ビード形状が得られるという効
果を有する。EFFECTS OF THE INVENTION As described above, the present invention uses a high-speed rotating arc welding method, an arc sensor automatic groove profile control, and a ceramic backing material on the back surface of the groove to provide a large current and a high speed. We can perform butt welding of pipes with high quality and high efficiency by performing one side welding from the outer surface of the pipe in all positions.
Further, it has an effect that a high quality and a good back bead shape can be obtained.
第１図は本発明の溶接方法に用いられる自動溶接機の概
略構成図、第２図は高速回転アークの原理図、第３図は
アークセンサ開先ならいの原理図、第４図（ａ），
（ｂ），（ｃ）は開先形状と裏当材の拡大断面図、第５
図は溶接されたビードの断面の積層状態を示した説明
図、第６図（ａ），（ｂ）は溝付き裏当材を示す断面図
である。 １……溶接機本体、２……溶接トーチ、３……モータ、
４……歯車機構、５……ｘ軸スライドブロック、６……
ｙ軸スライドブロック、７……溶接ワイヤ、10……パイ
プ、12……ガイドレール、14……開先、18……裏当材、
20……軸受部、21……電極ノズル、22……通電チップ。FIG. 1 is a schematic configuration diagram of an automatic welding machine used in the welding method of the present invention, FIG. 2 is a principle diagram of a high-speed rotating arc, FIG. 3 is a principle diagram of an arc sensor groove profile, and FIG. 4 (a). ，
(B) and (c) are groove shapes and enlarged sectional views of the backing material,
The figure is an explanatory view showing the laminated state of the cross section of the welded bead, and FIGS. 6 (a) and 6 (b) are cross sectional views showing the grooved backing material. 1 ... Welder body, 2 ... Welding torch, 3 ... Motor,
4 ... Gear mechanism, 5 ... x-axis slide block, 6 ...
y-axis slide block, 7 ... welding wire, 10 ... pipe, 12 ... guide rail, 14 ... groove, 18 ... backing material,
20 …… Bearing part, 21 …… Electrode nozzle, 22 …… Energizing tip.
Claims (1)
合せ端面に環状溝の底部がＶ形となる形状の狭開先又は
Ｖ開先を形成し、パイプ内面側にセラミックス製の裏当
材を配し、自動溶接機をパイプ外面に取り付けた円周ガ
イドレール上に走行させながらアークの回転速度を10Hz
以上、アークの回転直径を1.0〜4.0mmとした高速回転ア
ークによるガスシールドアーク溶接法によりアークセン
サによる開先自動ならい制御を行いながらワイヤ径0.8
〜1.6mmでパイプの外面から全姿勢で片面溶接すること
を特徴とするパイプの片面溶接方法。1. In butt welding of pipes, a narrow groove or V groove having a V-shaped bottom of an annular groove is formed on the butt end surface of the pipe, and a ceramic backing material is provided on the inner surface of the pipe. Then, while running the automatic welding machine on the circumferential guide rail attached to the outer surface of the pipe, the arc rotation speed is 10 Hz.
As described above, the wire diameter is 0.8 while controlling the groove automatically by the arc sensor by the gas shield arc welding method with the high-speed rotating arc with the arc rotating diameter of 1.0 to 4.0 mm.
One-sided welding method for pipes, which is one-sided welding in all positions from the outer surface of the pipe up to 1.6 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33037890A JPH0694069B2 (en) | 1990-11-30 | 1990-11-30 | One-sided welding method for pipes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP33037890A JPH0694069B2 (en) | 1990-11-30 | 1990-11-30 | One-sided welding method for pipes |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04200975A JPH04200975A (en) | 1992-07-21 |
| JPH0694069B2 true JPH0694069B2 (en) | 1994-11-24 |
Family
ID=18231937
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP33037890A Expired - Lifetime JPH0694069B2 (en) | 1990-11-30 | 1990-11-30 | One-sided welding method for pipes |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0694069B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3362357B2 (en) * | 1993-08-24 | 2003-01-07 | 忠弘 大見 | Welded joints and welding methods |
| CN113351963A (en) * | 2021-06-28 | 2021-09-07 | 中国电建集团山东电力建设第一工程有限公司 | Reverse backing welding method for large-diameter stainless steel fused salt pipeline |
-
1990
- 1990-11-30 JP JP33037890A patent/JPH0694069B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04200975A (en) | 1992-07-21 |
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