JPS59163081A - Automatic controlling method of penetration welding - Google Patents

Automatic controlling method of penetration welding

Info

Publication number
JPS59163081A
JPS59163081A JP3711583A JP3711583A JPS59163081A JP S59163081 A JPS59163081 A JP S59163081A JP 3711583 A JP3711583 A JP 3711583A JP 3711583 A JP3711583 A JP 3711583A JP S59163081 A JPS59163081 A JP S59163081A
Authority
JP
Japan
Prior art keywords
welding
arc voltage
electrode
groove
distance
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.)
Pending
Application number
JP3711583A
Other languages
Japanese (ja)
Inventor
Hiroshi Shimoyama
博司 下山
Tetsuo Nitta
新田 哲夫
Yusaku Sugimoto
杉本 裕策
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Heavy Industries Ltd
Original Assignee
Mitsubishi Heavy Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Heavy Industries Ltd filed Critical Mitsubishi Heavy Industries Ltd
Priority to JP3711583A priority Critical patent/JPS59163081A/en
Publication of JPS59163081A publication Critical patent/JPS59163081A/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K9/00Arc welding or cutting
    • B23K9/06Arrangements or circuits for starting the arc, e.g. by generating ignition voltage, or for stabilising the arc
    • B23K9/073Stabilising the arc
    • B23K9/0731Stabilising of the arc tension

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • Arc Welding In General (AREA)

Abstract

PURPOSE:To enable automatic control of penetration welding in the stage of welding automatically a groove with a TIG welding machine by controlling the position of an electrode in accordance with the result of comparison with a reference value to maintain a specified arc voltage and controlling at the same time the rate of the wire to be added. CONSTITUTION:Automatic welding of a single Vee groove 2 formed of objects 1, 1' to be welded by TIG welding is accomplished by detecting the arc voltage fluctuating with the change in the root gap (g) of the groove 2 with a detector 21, comparing the arc voltage with a reference arc voltage set in a standard arc voltage setter 22 in a comparator 23, supplying the output therefrom via a servocontrol amplifier 24 to a driving motor 7 to move vertically a welding torch 9 and regulating the height of an electrode 10 attached thereto to control the arc voltage constant. The distance A of the arc from the surface of the objects to be welded is detected at the same instant by a distance detector 12 moving vertically together with the electrode 10 and a wire feeder 13 is controlled in accordance with the detected distance to control the feed rate of the wire to the groove 2, by which the automatic control of penetration welding is accomplished.

Description

【発明の詳細な説明】 4ノ 本発明は裏波溶接自動制御方法に関する。[Detailed description of the invention] 4 no The present invention relates to an automatic control method for Uranami welding.

近年、原動機、船舶等の製造において配管溶接工事は膨
大なものとなっており、品質保証上従来からその自動溶
接化が図られてきている。
In recent years, pipe welding work has become enormous in the manufacture of motors, ships, etc., and automatic welding has been attempted for quality assurance.

しかしながら、これまでの自動化の手段は単に溶接トー
チの遅進、ワイヤ送給の機械化、溶接電流・電圧の高精
度制御化に止まっている。これら溶接パラメータの再現
精度の変動率は1〜2%以内に収まってきているものの
、配管突合せ溶接継手では大口径となるほど開先精度が
上記範囲の程度には収まらないため、特に七の初層ルー
トパスの裏波溶接の自動化は不可能とされてきた。すな
わち、従来の自動溶接法では溶接パラメータの標準条件
をいかにして一定に保つかに重点を置いておシ、ルート
ギャップの変化に適応して制御することができない。し
たがって、従来の自動溶接法をそのまま裏波溶接に適用
しようとすると、ルートギャップが過小の部分では入熱
が不足して裏波が出す、一方過大の部分では溶は落ちを
生じるため、何れの場合にも欠陥品となってしまう。こ
のため、現状でけ高熟練作業者が溶接現象を目視して微
妙な条件コントロールを行ない裏波溶接を行なっている
However, conventional means of automation have been limited to simply slowing down the welding torch, mechanizing wire feeding, and highly accurate control of welding current and voltage. Although the rate of variation in the reproducibility of these welding parameters has fallen within 1 to 2%, the larger the diameter of pipe butt welded joints, the more the groove accuracy does not fall within the above range. It has been considered impossible to automate root pass Uranami welding. That is, in conventional automatic welding methods, emphasis is placed on how to keep the standard conditions of welding parameters constant, and control cannot be adapted to changes in the root gap. Therefore, if we try to apply the conventional automatic welding method to Uranami welding as is, in areas where the root gap is too small, there will be insufficient heat input and Uranami will be produced, whereas in areas where the root gap is too large, melt will drop, resulting in In some cases, the product may be defective. For this reason, at present, highly skilled workers visually observe welding phenomena and perform delicate control of conditions to carry out Uranami welding.

本発明は上記事情に鑑みてなされたものであシ、従来か
ら自動化が図られてきている仕上溶接とともに全溶接の
自動化を確立し、品質保証と近い将来の高熟練作業者の
不足に対処し得る裏波溶接の自動制御方法を提供しよう
とするものである。
The present invention was made in view of the above circumstances, and aims to establish automation of all welding as well as finish welding, which has been automated in the past, and to ensure quality and address the shortage of highly skilled workers in the near future. The purpose of this invention is to provide an automatic control method for Uranami welding.

すなわち、本発明の裏波溶接の自動制御方法は被溶接物
の開先上に配設される上下動可能な電極と、該電極とと
もに上下動し、被溶接物表面との距離を検出する手段と
、開先内の前記電極先端近傍に溶接ワイヤを供給するワ
イヤ送給機とを有する溶接装置を用いて裏波溶接の自動
制御を行なうに際し、前記開先のルートギャップの変化
に伴なって変動するアーク電圧を検出し、基準値と比較
してアーク電圧ヲー、定とするように前記電極の高さを
制御し、該電極と同時に上下動する前記距離検出手段に
より被溶接物表面との距離を検出し、基準値との比較に
基づいて前記ワイヤ送給機からのワイヤ添加量を制御す
ることを特徴とするものである゛・以下、本発明方法の
実施例を図全参照して説明する。
That is, the automatic control method for uranami welding of the present invention includes an electrode that is disposed on the groove of the workpiece and is movable up and down, and a means that moves up and down together with the electrode to detect the distance to the surface of the workpiece. and a wire feeder that supplies a welding wire near the tip of the electrode in the groove to automatically control uranami welding. The height of the electrode is controlled to keep the arc voltage constant by detecting the varying arc voltage and comparing it with a reference value. The method is characterized in that the distance is detected and the amount of wire added from the wire feeder is controlled based on the comparison with a reference value. explain.

図中1,1′は互いに溶接されるべき被溶接物(配管の
突合せ継手)であり、両者の被溶接物1.1′間にはV
開先2が形成されており、この■開先2にはビード3が
形成される。前記一方の被溶接物1′にはその外周面に
沿ってレール4がフラングされており、このレール4に
は回転台車5が搭載されている。この回転台車5の前記
V開先2上方には上下スライド6が配設されている。こ
の上下スライド6上端には駆動モータ7が取付けられて
おり、上下スライド6に沿って上下動するスライド可動
部゛8を駆動させるようになっている。このスライド可
動部8にはTIG溶接トーチ9卆取付けられ、その先端
からタングステン電極1oを前記V開先2内に突出させ
ている。また、スライド可動部8にはアーム11を介し
て前記他方の被溶接物1上方に位置するように例えば電
磁上ンサからなる距離検出器12が取付けられている。
In the figure, 1 and 1' are objects to be welded together (butt joints of pipes), and there is a V between the two objects 1 and 1'.
A groove 2 is formed, and a bead 3 is formed in this groove 2. A rail 4 is flanged along the outer circumferential surface of one of the objects to be welded 1', and a rotary cart 5 is mounted on this rail 4. A vertical slide 6 is disposed above the V-shaped groove 2 of the rotary cart 5. A drive motor 7 is attached to the upper end of the vertical slide 6 to drive a slide movable portion 8 that moves up and down along the vertical slide 6. Nine TIG welding torches are attached to this slide movable part 8, and a tungsten electrode 1o is made to protrude into the V-groove 2 from its tip. Further, a distance detector 12 made of, for example, an electromagnetic sensor is attached to the slide movable portion 8 via an arm 11 so as to be located above the other workpiece 1 .

この距離検出器12は被溶接物1からの距離に比例して
リニアな出力が得られるようになっている。更に、前記
台車5にはワイヤ送給機13が取付けられており、溶接
ワイヤ14を前記V開先2内の前記電極10先端近傍に
送給するようになっている。
This distance detector 12 is designed to provide a linear output in proportion to the distance from the object 1 to be welded. Further, a wire feeder 13 is attached to the cart 5, and is configured to feed a welding wire 14 to the vicinity of the tip of the electrode 10 within the V-groove 2.

なお、前記溶接トーチ9と被溶接物間には図示しない電
源が接続されている。
Note that a power source (not shown) is connected between the welding torch 9 and the object to be welded.

次に、前記TIG溶接装置の制御部について説明する。Next, the control section of the TIG welding apparatus will be explained.

図中21はアーク電圧検出器であり、前記溶接トーチ9
と被溶接物1とに接続されている。
21 in the figure is an arc voltage detector, and the welding torch 9
and the workpiece 1 to be welded.

このアーク電圧検出器21は標準アーク電圧設定器22
が接続された比較器23に接続されている。更に、この
比較器24はブーデアンゾ24金介して前記駆動モータ
7に接続されている。
This arc voltage detector 21 is a standard arc voltage setting device 22.
The comparator 23 is connected to the comparator 23. Furthermore, this comparator 24 is connected to the drive motor 7 through 24-karat gold.

一方、図中25は出力電圧検出器で61、前記距離検出
器12と接続されている。この出力電力検出器25は標
準電圧設定器26が接続された比較反転増幅器27に接
続されている。この比較反転増幅器27はワイヤ送給速
度設定器28が接続された加算器29に接続されている
On the other hand, 25 in the figure is an output voltage detector, which is connected to 61 and the distance detector 12. This output power detector 25 is connected to a comparison inverting amplifier 27 to which a standard voltage setting device 26 is connected. This comparison inverting amplifier 27 is connected to an adder 29 to which a wire feed speed setting device 28 is connected.

更に、この加算器29はサーボアンfaoを介して前記
ワイヤ送給’fl!U13と接続されている。
Furthermore, this adder 29 inputs the wire feed 'fl!' via the servo amplifier fao. Connected to U13.

上記溶接装置を用いた裏波溶接の自動制御方法を説明す
る。
An automatic control method for Uranami welding using the above welding device will be explained.

(1)予め適正溶接電流と台車5の適正走行速度を設定
する。また、適正アーク電圧を標準アーク電圧設定器2
2に、ワイヤ送給機13の適正送給速度をワイヤ送給速
度設定器2Hにそれぞれ入力しておく。更に、標準のル
ートギャップgの時に、良好な裏波ビードを形成する状
態での適正ビード高さD1アーク長V及び電極1θ先端
と距離検出器12先端との距離A(一定値)を加えた合
計値B (=D十V+A )から被溶接物1,1′の肉
厚tを差引いた値cを求める。このCの値は標準のルー
トギャップgの時に、良好な裏波ビードを形成する状態
での距離検出器12と被溶接物1表面との距離であり、
この距離Cに比例する電圧を標準電圧設定器26に入力
しておく。
(1) An appropriate welding current and an appropriate running speed of the trolley 5 are set in advance. Also, set the appropriate arc voltage using the standard arc voltage setting device 2.
2, the appropriate feeding speed of the wire feeder 13 is input into the wire feeding speed setting device 2H. Furthermore, when the standard root gap g is used, the appropriate bead height D1, arc length V, and distance A (constant value) between the tip of the electrode 1θ and the tip of the distance detector 12 are added to form a good Uranami bead. A value c is obtained by subtracting the wall thickness t of the objects to be welded 1, 1' from the total value B (=D+V+A). The value of C is the distance between the distance detector 12 and the surface of the workpiece 1 when a good Uranami bead is formed at the standard root gap g,
A voltage proportional to this distance C is input into the standard voltage setting device 26.

(11)  起動ボタンを押すと、電極1θと被溶接物
1,1′との間にアークが発生し、溶接ワイヤ14が、
アーク中に添加されるとともに、台車5が走行を始める
(11) When the start button is pressed, an arc is generated between the electrode 1θ and the objects to be welded 1, 1', and the welding wire 14
As soon as it is added to the arc, the truck 5 starts running.

(川)溶接中にアーク電圧検出器21によって検出され
る実際のアーク電圧が、標準アーク電圧設定器22で設
定される標準アーク電圧に対して変動すれば、比較器2
3から偏差電圧がブーyl?アンゾ24を介して連動モ
ータ7に出力され、この駆動モータ?により溶接トーチ
9を上下動させるようになっている。この結果、アーク
長Vが一定に保たれ、実際のアーク電圧を標準アーク電
圧に修正する。
(River) If the actual arc voltage detected by the arc voltage detector 21 during welding fluctuates with respect to the standard arc voltage set by the standard arc voltage setting device 22, the comparator 2
Is the deviation voltage from 3? It is output to the interlocking motor 7 via the Anzo 24, and this drive motor? The welding torch 9 is moved up and down. As a result, the arc length V is kept constant and the actual arc voltage is corrected to the standard arc voltage.

(IV)  こうした状態でルートギャッ7″rが変動
して標準より過小になると、溶込みが阻害されて裏波が
出なくなるにもかかわらず、ワイヤ添加量が同じである
ためビード高さDが大きくなる。つづいて、ビード高さ
Dが大きくなった分だけ上記011)の動作により溶接
トーチ9が上昇し、これに伴なって距離検出器12の高
さCが大きくなジ、出力電圧調整器25への出力電圧が
増大する。この結果、標準電圧設定器26で設定される
標準電圧に対する変動分が比較反転増幅器27から偏差
電圧として加算器29に入力されてワイヤ送給速度設定
器28で設定される適正送給速度より小さい値とな9、
サーボアンプ30を介してワイヤ送給機13の送給速度
を減少させる。したがって、溶接入熱が被溶接物の開先
全より溶かすように働いて裏波を出やすくする。
(IV) If the root gap 7″r fluctuates under these conditions and becomes smaller than the standard, the bead height D will decrease because the amount of wire added is the same, even though penetration will be inhibited and no back waves will be produced. Subsequently, the welding torch 9 is raised by the operation 011) above by the amount that the bead height D has increased, and the height C of the distance detector 12 is accordingly increased, and the output voltage is adjusted. As a result, the variation with respect to the standard voltage set by the standard voltage setting device 26 is inputted from the comparison inverting amplifier 27 to the adder 29 as a deviation voltage, and the output voltage to the wire feeding speed setting device 28 is inputted to the adder 29 as a deviation voltage. If the value is smaller than the appropriate feeding speed set in 9,
The feeding speed of the wire feeder 13 is reduced via the servo amplifier 30. Therefore, the welding heat input works to melt the entire groove of the workpiece, making it easier to generate underwaves.

(1/)上記Ov)と逆にルートギャップgが変動して
標準より過大になると、溶は洛ちが生じる寸前となり、
裏波ビードが垂れ下がってビード高さDが大きくなり1
.上記+IV)と逆に溶接トーチ9が下降して距離検出
器12の高さCが小さくな9、出力電圧調整器25への
出力電圧が減少する。この結果、標準電圧設定器26で
設定される標準電圧に対する変動分が比較反転増幅器2
?゛から偏差電圧として加算器29に入力されてワイヤ
送給速度設定器28で設定される適正送給速度よシ大き
い値となり、サーボアンプ30を介してワイヤ送給機1
3の送給速度全増大させる。したがって、溶金量が増大
して溶は落ちを防止する。
(1/) Contrary to the above Ov), if the root gap g fluctuates and becomes larger than the standard, the melt will be on the verge of a drop,
The Uranami bead hangs down and the bead height D increases 1
.. Contrary to +IV) above, the welding torch 9 descends, the height C of the distance detector 12 becomes smaller 9, and the output voltage to the output voltage regulator 25 decreases. As a result, the variation with respect to the standard voltage set by the standard voltage setter 26 is
?゛ is input as a deviation voltage to the adder 29, which becomes a value larger than the appropriate feeding speed set by the wire feeding speed setting device 28, and is sent to the wire feeder 1 via the servo amplifier 30.
Increase the total feeding speed of 3. Therefore, the amount of molten metal increases and the molten metal is prevented from dripping.

しかして、本発明方法によればルートギャップgの大小
に伴う裏波ビード高さDの変動全距離検出器12により
検出し、ワイヤ添加量を調整して均一な裏波ビード全自
動的に形成することができる。
According to the method of the present invention, the variation in the Uranami bead height D due to the size of the root gap g is detected by the full distance detector 12, and the amount of added wire is adjusted to automatically form a uniform Uranami bead. can do.

なお、上記実施例では距離検出器12として電磁センサ
を用いたが、これに限らず、被溶接物表面からの距離に
比例してリニアな出力が得られるものであれは、例えば
差動トランス、光セン丈、流体セン丈等を用いることが
できる。
In the above embodiment, an electromagnetic sensor is used as the distance detector 12, but the sensor is not limited to this, and any sensor that can obtain a linear output in proportion to the distance from the surface of the workpiece may be used, such as a differential transformer, Optical sensor length, fluid sensor length, etc. can be used.

以上詳述した如く、本発明の裏波浴接の自動制御方法に
よれば、開先精度の変動に適応して、溶接条件を制御で
き、これまで困難視されてきたルートパスの裏波溶接が
自動化できるという顕著な効果を奏するものである。
As described in detail above, according to the automatic control method for uranami bath welding of the present invention, it is possible to control welding conditions by adapting to fluctuations in groove precision, and it is possible to perform uranami welding of the root pass, which has been considered difficult until now. This has the remarkable effect of being able to be automated.

【図面の簡単な説明】[Brief explanation of the drawing]

図は本発明の実施例において用いられる溶接装置の構成
図である。 1.1′・・・被溶接物、2・・V開先、3・・ビード
、4・・・レール、5・・・回転台車、6・・・上下ス
ライド、7・・・駆動モータ、8・・・スライド可動部
、9・・・TlG11トーチ、10・・・タングステン
電極、11アーム、12・・・距離検出器、21・・・
アーク電圧検出器、22・・・標準アーク電圧設定器、
23・・・比較器、24.30・・・サーボアンプ、2
5・・・出力電圧調整器、26・・・標準電圧設定器、
27・・・比較反転増幅器、28・・・ワイヤ送給速度
設定器、29・・・加算器。
The figure is a configuration diagram of a welding device used in an embodiment of the present invention. 1.1'... Workpiece to be welded, 2... V-bevel, 3... Bead, 4... Rail, 5... Rotating trolley, 6... Vertical slide, 7... Drive motor, 8... Slide movable part, 9... TlG11 torch, 10... Tungsten electrode, 11 arm, 12... Distance detector, 21...
Arc voltage detector, 22... standard arc voltage setting device,
23...Comparator, 24.30...Servo amplifier, 2
5... Output voltage regulator, 26... Standard voltage setting device,
27... Comparison inverting amplifier, 28... Wire feed speed setting device, 29... Adder.

Claims (1)

【特許請求の範囲】[Claims] 被溶接物の開先上に配設される上下動可能な電極と、該
電極とともに上下動し、被溶接物表面との距離を検出す
る手段と、開先内の前記電極先端近傍に溶接ワイヤを供
給するワイヤ送給機とを有する溶接装置を用いて裏波溶
接の自動制御を行なうに際し、前記開先のルートギャッ
プの変化に伴なって変動するアーク電圧を検出し、基準
値と比較し′てアーク電圧を一定とするように前記電極
の高さを制御し、該電極と同時に上下動する前記距離検
出手段により被溶接物表面との距離を検出し、基準値と
の比較に基づいて前記ワイヤ送給機からのワイヤ添加量
を制御することを%徴とする裏波溶接の自動制御方法0
A vertically movable electrode disposed on the groove of the workpiece, a means for moving up and down with the electrode to detect the distance to the surface of the workpiece, and a welding wire near the tip of the electrode within the groove. When performing automatic control of Uranami welding using a welding device having a wire feeder that supplies The height of the electrode is controlled so as to keep the arc voltage constant, and the distance to the surface of the workpiece is detected by the distance detection means that moves up and down simultaneously with the electrode, and the distance to the surface of the workpiece is detected based on the comparison with a reference value. An automatic control method for uranami welding that includes controlling the amount of wire added from the wire feeder 0
JP3711583A 1983-03-07 1983-03-07 Automatic controlling method of penetration welding Pending JPS59163081A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3711583A JPS59163081A (en) 1983-03-07 1983-03-07 Automatic controlling method of penetration welding

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3711583A JPS59163081A (en) 1983-03-07 1983-03-07 Automatic controlling method of penetration welding

Publications (1)

Publication Number Publication Date
JPS59163081A true JPS59163081A (en) 1984-09-14

Family

ID=12488597

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3711583A Pending JPS59163081A (en) 1983-03-07 1983-03-07 Automatic controlling method of penetration welding

Country Status (1)

Country Link
JP (1) JPS59163081A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0571624A1 (en) * 1990-04-17 1993-12-01 Kabushiki Kaisha Komatsu Seisakusho Method of controlling torch height in plasma cutting
CN102873432A (en) * 2012-09-29 2013-01-16 南京工程学院 Device for realizing arc-stabilizing effect by applying auxiliary external electric field between slag and metal of submerged-arc welding with welding and usage of device
CN110814469A (en) * 2019-10-17 2020-02-21 南京工业大学 Multi-mode automatic arc voltage regulation control system

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0571624A1 (en) * 1990-04-17 1993-12-01 Kabushiki Kaisha Komatsu Seisakusho Method of controlling torch height in plasma cutting
CN102873432A (en) * 2012-09-29 2013-01-16 南京工程学院 Device for realizing arc-stabilizing effect by applying auxiliary external electric field between slag and metal of submerged-arc welding with welding and usage of device
CN110814469A (en) * 2019-10-17 2020-02-21 南京工业大学 Multi-mode automatic arc voltage regulation control system

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