JPH06270B2 - One-sided first layer welding method for pipes - Google Patents
One-sided first layer welding method for pipesInfo
- Publication number
- JPH06270B2 JPH06270B2 JP14839289A JP14839289A JPH06270B2 JP H06270 B2 JPH06270 B2 JP H06270B2 JP 14839289 A JP14839289 A JP 14839289A JP 14839289 A JP14839289 A JP 14839289A JP H06270 B2 JPH06270 B2 JP H06270B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- arc
- groove
- speed
- pipe
- 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
Landscapes
- Butt Welding And Welding Of Specific Article (AREA)
- Arc Welding Control (AREA)
Description
【発明の詳細な説明】 [産業上の利用分野] 本発明、パイプライン敷設工事におけるパイプの片面初
層溶接方法に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a single-sided first layer welding method for pipes in pipeline laying work.
[従来の技術] パイプの円周突合せ溶接における開先形状は一般に第3
図(a)に示すように形成されており、溶接は同図(b)に示
すように行われる。すなわち、まず、内面溶接機により
ルートパスIを溶接する。このルートパスIの溶接速度
は75cm/分位で、トーチのウィーピングは行わない。[Prior Art] Generally, the groove shape in the circumferential butt welding of pipes is the third
It is formed as shown in Figure (a), and welding is performed as shown in Figure (b). That is, first, the root path I is welded by the inner surface welding machine. The welding speed of this route pass I is about 75 cm / minute, and the torch is not weeped.
次に、このルートパスIの終了後、パイプの外面より外
面溶接機によりホットパスH、フィラパスF、キャップ
パスCの順序で溶接を行う。Next, after the completion of this route pass I, welding is performed from the outer face of the pipe in the order of hot pass H, filler pass F and cap pass C by an outer surface welding machine.
ホットパスHの溶接速度は100cm/分位で、トーチの
ウィーピングは行わない。The welding speed of the hot path H is about 100 cm / minute, and the torch is not weeped.
フライパスF、キャップパスCの溶接速度は30〜40
cm/分位で、それぞれ継手の開先の幅に応じたウィービ
ング(通常6〜7mm)を行いながら溶接する。Welding speed of fly pass F and cap pass C is 30-40
Welding is performed in cm / quantile while weaving (usually 6 to 7 mm) according to the groove width of the joint.
[発明が解決しようとする課題] 本発明は、パイプの円周突合せ溶接における初層溶接の
溶接速度の向上と溶接品質の安定確保を目的とするもの
である。[Problems to be Solved by the Invention] The present invention is intended to improve the welding speed of initial layer welding in circumferential butt welding of pipes and to ensure stable welding quality.
前項で述べたように、従来技術では初層ルートパス溶接
の溶接速度は約75cm/分であり、ウィービングは行っ
ていない。すなわち、従来技術ではウィービングを行っ
ていないため、アークセンサによる開先自動倣い制御を
行うことができないため、初層溶接機の溶接トーチを継
手の開先中心に合わせるのに時間・労力を要し、時とし
てワイヤの曲がりぐせや溶接トーチの狙い位置ズレなど
の要因により初層溶接ビードに欠陥が生じやすいという
問題があつた。As described in the previous section, in the prior art, the welding speed of the initial layer root pass welding is about 75 cm / min, and weaving is not performed. That is, since weaving is not performed in the conventional technology, it is not possible to perform groove automatic copying control by the arc sensor, so it takes time and labor to align the welding torch of the first layer welding machine with the groove center of the joint. However, sometimes there was a problem that defects were likely to occur in the first-layer welding bead due to factors such as the bending of the wire and displacement of the target position of the welding torch.
アークセンサとは、溶接トーチを開先内で開先幅方向に
揺動し、溶接電流やアーク電圧の波形から溶接トーチの
開先内における位置ズレを検出し、それを修正すること
により溶接線を自動的に追従する方法である。しかし、
従来技術におけるアークセンサでは、振動式ウィービン
グ方式をとっているため、機構的制約によりウィービン
グ周波数は10Hzを越えることができないため、アーク
センサの応答性やビード形状の面から適用できる溶接速
度が制限されており、従来技術の初層ルートパス溶接に
おける75cm/分の溶接速度では適用できなかった。The arc sensor swings the welding torch in the groove width direction inside the groove, detects the positional deviation in the groove of the welding torch from the waveform of the welding current and arc voltage, and corrects it to make the welding line. Is a method of automatically following. But,
Since the arc sensor in the prior art adopts the vibration type weaving method, the weaving frequency cannot exceed 10 Hz due to the mechanical constraint, so that the welding speed that can be applied is limited due to the responsiveness of the arc sensor and the bead shape. Therefore, it cannot be applied at the welding speed of 75 cm / min in the first layer root pass welding of the prior art.
また、従来技術の初層ルートパス溶接の溶接電流は約2
00Aである。これは、溶接トーチの運棒(ウィービン
グ)を行っていないため、これ以上の大電流を適用する
と、特に上向姿勢においてビード形状が凸型となるた
め、200A程度に溶接電流が制約されており、したが
ってこれ以上の高速度溶接は不可能とされていた。In addition, the welding current of the first-layer root-pass welding of the prior art is about 2
It is 00A. This is because the welding torch is not moved (weaving), and if a larger current than this is applied, the bead shape becomes convex especially in the upward posture, so the welding current is limited to about 200A. Therefore, higher speed welding was not possible.
上記問題点を整理すると次の2つのである。The above two problems are summarized as follows.
(1)従来技術における初層ルートパスの溶接では、トー
チのウィービングを行うことができないため、アークセ
ンサによる開先自動倣い制御を適用できず、溶接トーチ
の位置決めに時間・労力を要し、時として外乱により欠
陥を生じる。(1) In the welding of the first layer route pass in the conventional technology, since weaving of the torch cannot be performed, the groove automatic copying control by the arc sensor cannot be applied, and it takes time and labor to position the welding torch, and sometimes it is necessary. Disturbance causes defects.
(2)溶接トーチの運棒(ウィービング)を行うことがで
きないため、ビード形状の問題より溶接電流が200A
程度に制約されているので、これ以上の高速度溶接は不
可能であった。(2) Welding current is 200A due to the problem of the bead shape because the weaving of the welding torch cannot be performed.
Due to the limited extent, higher speed welding was not possible.
[課題を解決するための手段] 上記問題点を解決するため、本発明では、溶接プロセス
として高速回転アーク法による消耗電極式アーク溶接方
法を採用した。[Means for Solving the Problems] In order to solve the above problems, in the present invention, a consumable electrode type arc welding method by a high speed rotating arc method is adopted as a welding process.
本方法においては、アーク回転速度Nは、10Hz〜15
0Hz(下限値は従来法の振動式アークセンサのウィービ
ング周波数の上限、上限値は現在の実績による)、 アークの回転直径Dは1〜4mm、 溶接電流は200〜500A(下限値は従来技術の溶接
電流、上限値は溶接プロセスとしての上限)、 溶接速度は75〜300cm/分(下限値は従来技術の溶
接速度、上限値は現状のアークセンサの実績)である。In this method, the arc rotation speed N is 10 Hz to 15 Hz.
0Hz (the lower limit is the upper limit of the weaving frequency of the conventional vibration type arc sensor, the upper limit depends on the current track record), the rotating diameter D of the arc is 1 to 4 mm, the welding current is 200 to 500 A (the lower limit is the conventional value The welding current and the upper limit are the upper limit of the welding process, and the welding speed is 75 to 300 cm / min (the lower limit is the welding speed of the prior art, and the upper limit is the current arc sensor performance).
[作用] 本方法では、アークを1秒間に10〜150Hzの高速
で回転ウィービングを行っているため、75〜300cm
/分という高速度溶接においてもアークセンサによる開
先自動倣いが達成されるため(1)の問題を解決する。[Operation] In this method, since the arc is rotated and weaved at a high speed of 10 to 150 Hz per second, it is 75 to 300 cm.
The problem of (1) is solved because the automatic groove chamfering by the arc sensor can be achieved even in high-speed welding of / min.
また、アークの高速回転により、アークの圧力や入熱が
分散し、ビード表面形状が平滑化されるため、200〜
500Aの大電流、75〜300cm/分の高速度溶接に
おいても良好なビード形状が得られるため(2)の問題を
解決する。Further, the high speed rotation of the arc disperses the pressure and heat input of the arc and smoothes the bead surface shape.
The problem (2) is solved because a good bead shape can be obtained even at a high current of 500 A and high speed welding of 75 to 300 cm / min.
すなわち、パイプの突合せ円周溶接において、上記の
回転アーク法を用いれば、アークの回転数を容易に上げ
ることができるとともに、管端に形成された底部がV形
の環状溝内を自動的に倣わせることができる。したがっ
て、自動溶接機をパイプ外面に仮付けした円周ガイドレ
ールに沿って走行させながらアークの回転数を10〜1
50Hz、アークの回転直径を1〜4mmとした高速回転式
アークセンサの作用下で溶接すれば、初層を全姿勢で円
周溶接することができ、しかも溶接電流が200〜50
0Aという大電流の下で裏当材を用いて溶接することに
より、初層溶接と同時に正常な裏波が形成され、かつ溶
接速度が75〜300cm/分という高速溶接が実現され
る。さらに、このようにして溶接された初層を基準に引
き続きフイラパス及びキャップパスを連続して溶接する
ことができる。That is, in the butt-circumferential welding of pipes, if the rotating arc method described above is used, the number of rotations of the arc can be easily increased, and the bottom formed at the pipe end automatically moves in the V-shaped annular groove. Can be imitated. Therefore, while the automatic welding machine is running along the circumferential guide rail temporarily attached to the outer surface of the pipe, the arc rotation speed is 10 to 1
If welding is performed under the action of a high-speed rotating arc sensor with a rotating diameter of the arc of 50 Hz and an arc rotating diameter of 1 to 4 mm, the first layer can be circumferentially welded in all positions, and the welding current is 200 to 50.
By welding with the backing material under a large current of 0 A, normal backwater is formed at the same time as the first layer welding, and high-speed welding with a welding speed of 75 to 300 cm / min is realized. Further, the filler pass and the cap pass can be continuously welded continuously based on the first layer welded in this way.
[実施例] 以下、図面を用いて本発明の溶接方法を説明する。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つて
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。
なお、16は開先14に対向して配された銅板等の裏当
材である。[Examples] Hereinafter, a welding method of the present invention will be described with reference to the drawings. First
The figure is a schematic configuration diagram of an automatic welding machine. The welding machine body 1 is installed so as to be self-propelled along a circumferential guide rail 12 temporarily attached to the outer surface of the pipe 10. A welding torch 2 provided in the welder body 1 is rotated by a motor 3 via a gear mechanism 4, and an x-axis slide block 5 that is movable in the width direction of the groove 14 (x-axis) and a torch axial direction ( y-axis slide block 6 that can move to y-axis)
Is supported through. 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 rotating diameter D of the arc is determined by the eccentric distance. This allows the rotating arc method to be implemented.
Reference numeral 16 is a backing material such as a copper plate arranged facing the groove 14.
第2図(a),(b)は本発明における開先形状の拡大断面図
であり、開先14の形状は底部14aがV形を有するス
トレートな環状溝14bに形成される。底部14aの傾
斜角度θは30°〜60°にされる。また、a寸法は1
〜2mmで、パイプの肉厚tが8〜25mmのものにおい
て、溝幅bは7〜8mm以下にされる。なお、開先14の
パイプ内面側に第2図(b)に示すように小さなルートフ
ェース14cを設けてもよい。2 (a) and 2 (b) are enlarged sectional views of the groove shape according to the present invention. The groove 14 is formed in a straight annular groove 14b having a V-shaped bottom 14a. The inclination angle θ of the bottom portion 14a is set to 30 ° to 60 °. Also, the a dimension is 1
The groove width b is set to 7 to 8 mm or less when the pipe thickness is 2 mm and the wall thickness t of the pipe is 8 to 25 mm. A small root face 14c may be provided on the inner surface of the groove 14 on the inner surface of the pipe as shown in FIG. 2 (b).
このように開先14の底部14aをV形に形成すること
により、第1図に示した溶接トーチ2を回転式アークセ
ンサの作用下で定アーク長のもとに底部14aの中心に
正確に倣わせることができ、外面ホットパスH(初層1
7)を全姿勢で円周溶接することができる。しかも、こ
の初層17の溶接と同時に裏波18を正常に出すことが
できる。By forming the bottom portion 14a of the groove 14 in the V-shape in this manner, the welding torch 2 shown in FIG. 1 can be accurately positioned at the center of the bottom portion 14a under the action of the rotary arc sensor under a constant arc length. Can be copied, and the external hot path H (first layer 1
7) can be circumferentially welded in all positions. Moreover, the back seam 18 can be normally produced simultaneously with the welding of the first layer 17.
具体例について説明すると、0.9mmφのソリッドワイ
ヤを使用し、アーク回転数N=50Hz、アーク回転直径
D=2〜3mm、溶接電流Ia=300A、溶接速度v=
2.0m/分とし、CO2ガス100%の雰囲気下で初
層17を溶接したところ、第2図(c)に示すような平滑
なビード形状が得られた。したがってまた、次にこの初
層17のビード上にフィラパスF及びキャップパスCを
順次積層溶接する場合においても、初層17を基準に回
転式アークセンサの作用下で溶接すればよく全積層溶接
を連続して行うことができるので、パイプの突合せ円周
溶接を高速度で実施することができる。Explaining a specific example, a solid wire of 0.9 mmφ is used, the arc rotation speed N = 50 Hz, the arc rotation diameter D = 2 to 3 mm, the welding current I a = 300 A, and the welding speed v =
When the first layer 17 was welded in an atmosphere of 100% CO 2 gas at 2.0 m / min, a smooth bead shape as shown in FIG. 2 (c) was obtained. Therefore, also in the case where the filler path F and the cap path C are sequentially laminated and welded on the bead of the first layer 17 next, welding may be performed under the action of the rotary arc sensor with the first layer 17 as a reference. Since it can be performed continuously, the butt circumferential welding of pipes can be performed at high speed.
[発明の効果] 以上のように本発明によれば、従来法のように内面溶接
機を使用せずパイプの外面からのみホットパスを回転ア
ーク法を用いて溶接し、そのときの溶接条件を前述のご
とく設定して行うものであるから、大電流かつ高速溶接
により溶接欠陥のないすぐれた初層溶接ができ、しかも
この初層を基準に全積層溶接を連続して行うことができ
るので、パイプの突合せ円周溶接を高速度で実施するこ
とができる。したがって、本溶接法によれば、施工期間
を従来法に比し約1/4以下に短縮でき、かつ設備、人
員の大幅な削減が可能になるという効果が得られる。[Effects of the Invention] As described above, according to the present invention, the hot path is welded using the rotary arc method only from the outer surface of the pipe without using the inner surface welding machine as in the conventional method, and the welding conditions at that time are described above. Since it is set as follows, it is possible to perform excellent first layer welding with no welding defects by high current and high speed welding, and furthermore, it is possible to perform all laminated welding continuously based on this first layer. Butt circumferential welding can be performed at high speed. Therefore, according to the present welding method, there is an effect that the construction period can be shortened to about 1/4 or less as compared with the conventional method, and the equipment and the personnel can be greatly reduced.
第1図は本発明の溶接方法に用いる自動溶接機の概略構
成図、第2図(a),(b)は開先形状の拡大断面図で、第2
図(c)はその開先における積層溶接の状態を示した図、
第3図(a)は従来の開先形状の拡大断面図で、第3図(b)
はその開先における積層溶接の状態を示した説明図であ
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…円周ガイドレール 14…開先 16…裏当材FIG. 1 is a schematic configuration diagram of an automatic welding machine used in the welding method of the present invention, and FIGS. 2 (a) and 2 (b) are enlarged sectional views of a groove shape.
Figure (c) shows the state of laminated welding at the groove,
FIG. 3 (a) is an enlarged sectional view of a conventional groove shape, and FIG. 3 (b)
FIG. 4 is an explanatory view showing a state of laminated welding at the groove. 1 ... Welder main 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 ... Circumferential guide rail 14 ... Groove 16 ... Backing material
Claims (1)
の突合せ端面に環状溝の底部がV形となる形状の開先を
形成し、パイプの内面側に裏当材を配し、自動溶接機を
パイプ外面に取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10〜150Hz、アークの回
転直径を1〜4mmとした高速回転アーク溶接法により開
先自動倣い制御を行いながら、溶接電流200〜500
A、溶接速度75〜300cm/分の条件で、パイプの外
面から初層を全姿勢で片面溶接することを特徴とするパ
イプの片面初層溶接方法。1. In butt-circumferential welding of pipes, a groove having a V-shaped bottom of an annular groove is formed on the butt end face of the pipe, and a backing material is arranged on the inner surface side of the pipe. While traveling on a circumferential guide rail attached to the outer surface of the pipe, while performing automatic groove tracking control by a high-speed rotating arc welding method with an arc rotation speed of 10 to 150 Hz and an arc rotation diameter of 1 to 4 mm, Welding current 200-500
A, a single-sided first-layer welding method for a pipe, characterized in that the first layer is welded from the outer surface of the pipe in all positions on one side at a welding speed of 75 to 300 cm / min.
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14839289A JPH06270B2 (en) | 1989-06-13 | 1989-06-13 | One-sided first layer welding method for pipes |
US07/512,742 US5030812A (en) | 1989-06-13 | 1990-04-23 | Method for one-side root pass welding of a pipe joint |
EP19900109340 EP0402648A3 (en) | 1989-06-13 | 1990-05-17 | Method for one-side root pass welding of a pipe joint |
KR1019900007413A KR920006416B1 (en) | 1989-06-13 | 1990-05-23 | Method for one-side root pass welding of a pipe joint |
CA 2018701 CA2018701C (en) | 1989-06-13 | 1990-06-11 | Method for one-side root pass welding of a pipe joint |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14839289A JPH06270B2 (en) | 1989-06-13 | 1989-06-13 | One-sided first layer welding method for pipes |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH0318476A JPH0318476A (en) | 1991-01-28 |
JPH06270B2 true JPH06270B2 (en) | 1994-01-05 |
Family
ID=15451753
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP14839289A Expired - Lifetime JPH06270B2 (en) | 1989-06-13 | 1989-06-13 | One-sided first layer welding method for pipes |
Country Status (2)
Country | Link |
---|---|
JP (1) | JPH06270B2 (en) |
CA (1) | CA2018701C (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102807141A (en) * | 2011-05-31 | 2012-12-05 | 株式会社日立制作所 | Elevator control device |
Families Citing this family (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3323028B2 (en) * | 1995-03-31 | 2002-09-09 | 株式会社日立製作所 | Automatic welding equipment and welding method |
US6279334B1 (en) | 1997-06-30 | 2001-08-28 | Zexel Cold Systems Company | Refrigerating apparatus for vehicles |
JP4922547B2 (en) * | 2003-12-01 | 2012-04-25 | 株式会社フジキン | Piping welding method and piping welding structure |
US20130001210A1 (en) * | 2011-07-01 | 2013-01-03 | Illinois Tool Works Inc. | Metal cored welding method and system |
CN111992860B (en) * | 2020-08-26 | 2022-08-02 | 广船国际有限公司 | Flux-cored wire deposited metal test method |
-
1989
- 1989-06-13 JP JP14839289A patent/JPH06270B2/en not_active Expired - Lifetime
-
1990
- 1990-06-11 CA CA 2018701 patent/CA2018701C/en not_active Expired - Fee Related
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102807141A (en) * | 2011-05-31 | 2012-12-05 | 株式会社日立制作所 | Elevator control device |
Also Published As
Publication number | Publication date |
---|---|
CA2018701C (en) | 1994-07-05 |
CA2018701A1 (en) | 1990-12-13 |
JPH0318476A (en) | 1991-01-28 |
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