JPS626908B2 - - Google Patents
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- Publication number
- JPS626908B2 JPS626908B2 JP55035362A JP3536280A JPS626908B2 JP S626908 B2 JPS626908 B2 JP S626908B2 JP 55035362 A JP55035362 A JP 55035362A JP 3536280 A JP3536280 A JP 3536280A JP S626908 B2 JPS626908 B2 JP S626908B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- arc
- consumable electrode
- current
- electrode
- 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
Links
- 238000003466 welding Methods 0.000 claims description 123
- 238000000034 method Methods 0.000 claims description 14
- 239000000463 material Substances 0.000 claims description 12
- 239000010953 base metal Substances 0.000 claims description 9
- 239000002184 metal Substances 0.000 description 9
- 238000010586 diagram Methods 0.000 description 4
- 238000001816 cooling Methods 0.000 description 3
- 230000004927 fusion Effects 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 230000008018 melting Effects 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000007711 solidification Methods 0.000 description 1
- 230000008023 solidification Effects 0.000 description 1
Description
【発明の詳細な説明】
本発明は消耗性電極式ガスシールドアーク溶接
方法、特に直流電源により消耗性電極の供給量に
応じて溶接電流を変化させ、超低周波パルスアー
クにより溶接を行なう消耗性電極式ガスシールド
アーク溶接方法の改良に関する。Detailed Description of the Invention The present invention relates to a consumable electrode type gas-shielded arc welding method, particularly a consumable welding method in which the welding current is changed according to the supply amount of the consumable electrode using a DC power source, and welding is performed using an ultra-low frequency pulsed arc. This article relates to improvements in electrode type gas shielded arc welding methods.
消耗性電極と溶接母材との間にアークを発生さ
せて溶接を行なう消耗電極式ガスシールドアーク
溶接方法において、特に立向上進溶接あるいは全
姿勢溶接等を行なう場合には、溶湯の垂れ落ちが
生じ易いことから、溶湯の溶融と凝固とを繰り返
しながら溶接を行なつている。このように溶湯の
溶融と凝固とを繰り返すために従来においては、
消耗性電極に溶接電源の正極を接続し溶接母材に
溶接電源の負極を接続して消耗性電極と溶接母材
との間に逆極性アークを発生させて溶接を行な
い、かつこのときの逆極性アークの溶接を第１図
に示された様な、ピーク電流１００とベース電流
１０２の繰り返しから成る超低周波パルス状の溶
接電流で行なつていた。 In the consumable electrode type gas-shielded arc welding method, in which an arc is generated between the consumable electrode and the welding base metal, dripping of molten metal is a problem, especially when vertical advancement welding or all-position welding is performed. Because this phenomenon is easy to occur, welding is performed by repeatedly melting and solidifying the molten metal. In order to repeat the melting and solidification of molten metal in this way, conventionally,
Welding is performed by connecting the positive pole of the welding power source to the consumable electrode and the negative pole of the welding power source to the welding base metal to generate a reverse polarity arc between the consumable electrode and the welding base metal. Polar arc welding was carried out using an extremely low frequency pulsed welding current consisting of repetitions of a peak current 100 and a base current 102 as shown in FIG.
なお、第１図において縦軸は消耗性電極と溶接
母材との間に流れる溶接電流を示しており、横軸
は時刻を示している。そして、通常の溶接の場合
にはピーク電流は200〜300Aに設定されベース電
流１０２は80〜160Aに設定される。 In FIG. 1, the vertical axis indicates the welding current flowing between the consumable electrode and the welding base material, and the horizontal axis indicates time. In the case of normal welding, the peak current is set to 200 to 300A, and the base current 102 is set to 80 to 160A.
このような超低周波数パルス状の溶接電流によ
りＶ開先の上進溶接を行なうには溶接電流が消耗
性電極の送給量により可変できるので、消耗性電
極（主にワイヤ電極を用いる）の送給量を多くし
第１図のピーク電流１００を流してＶ開先内を十
分溶融させ、一方、消耗性電極の送給量を少なく
し第１図のベース電流１０２を流して溶融池を冷
却凝固させるようにする。この結果、融合不良が
生ぜず、かつ溶湯の垂れ落ちがない溶接を行なう
ことができる。 In order to perform upward welding of a V-groove using such an ultra-low frequency pulsed welding current, the welding current can be varied by changing the feed rate of the consumable electrode, so it is necessary to use a consumable electrode (mainly a wire electrode). The feed rate was increased to flow a peak current of 100 in Figure 1 to sufficiently melt the inside of the V-groove, while the feed rate of the consumable electrode was decreased to flow a base current of 102 in Figure 1 to eliminate the molten pool. Allow to cool and solidify. As a result, welding can be performed without fusion failure and without dripping of molten metal.
なお、以上の説明において、消耗性電極の送給
量に応じて溶接電流を変化させる場合には消耗性
電極の送給量に応じてアーク電圧の調節制御を行
なう必要がある。 In addition, in the above description, when changing the welding current according to the feeding amount of the consumable electrode, it is necessary to perform adjustment control of the arc voltage according to the feeding amount of the consumable electrode.
しかしながら、以上のようにしてベース電流１
０２を得るために消耗性電極の送給量を減少させ
ることとすれば、ベース電流１０２が流れている
期間では消耗性電極の送給量が減少することとな
るので、以上説明した従来の溶接方法ではベース
電流１０２が流れている期間では溶接速度が低く
なつてしまうという欠点があつた。なお、全体と
して溶接速度を高めるためにはピーク電流１００
あるいはベース電流１０２の増加を図れば良いの
であるが、そうすると溶湯の垂れ落ちが生ずるこ
ととなつてしまい所期の目的を達成することがで
きなくなつてしまう。 However, as described above, the base current 1
If the feed rate of the consumable electrode is reduced in order to obtain 02, the feed rate of the consumable electrode will be reduced during the period when the base current 102 is flowing. This method has the disadvantage that the welding speed becomes low during the period when the base current 102 is flowing. In addition, in order to increase the overall welding speed, the peak current should be 100
Alternatively, it would be possible to increase the base current 102, but this would cause the molten metal to drip down, making it impossible to achieve the desired purpose.
本発明は上記従来の課題に鑑み為されたもので
あり、その目的は、溶湯の垂れ落ちが生ぜず、か
つ溶接速度が高い消耗電極式ガスシールドアーク
溶接方法を提供することにある。 The present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a consumable electrode type gas-shielded arc welding method that does not cause dripping of molten metal and has a high welding speed.
上記目的を達成するために本発明は、消耗性電
極と溶接母材との間にアークを発生させて溶接母
材の溶接を行なう消耗性電極式ガスシールドアー
ク溶接装置において、消耗性電極を正極とし溶接
母材を負極として消耗性電極と溶接母材との間で
逆極性アークを発生させ溶融池形成用逆極性アー
ク溶接を行なう逆極性アーク溶接状態と、消耗性
電極と溶接母材との間で正極性アークを発生させ
溶融池凝固用正極性アーク溶接を行なう正極性ア
ーク溶接状態と、を交互に繰り返して行なうこと
を特徴とする。 In order to achieve the above object, the present invention provides a consumable electrode type gas shielded arc welding apparatus that generates an arc between a consumable electrode and a welding base material to weld the welding base material. A reverse polarity arc welding state in which a reverse polarity arc is generated between the consumable electrode and the welding base material with the welding base metal as the negative electrode to perform reverse polarity arc welding for forming a molten pool, and a It is characterized by alternately repeating a positive polarity arc welding state in which a positive polarity arc is generated in between and positive polarity arc welding is performed for solidifying the molten pool.
すなわち、本発明は、前述した従来の場合と同
様に溶融池の形成と溶融池の冷却凝固とを繰り返
しながら溶接を行なうものであるが、溶融池の冷
却凝固のときには、正極性アークによる溶接を行
なう場合に入熱が少ないことに着目して、正極ア
ークによる溶接を行なつている。 That is, in the present invention, welding is performed while repeatedly forming a molten pool and cooling and solidifying the molten pool, as in the conventional case described above, but when cooling and solidifying the molten pool, welding is performed using a positive polarity arc. Focusing on the fact that there is little heat input when welding, positive electrode arc welding is used.
以下図面に基づいて本発明に係る消耗性ガスシ
ールドアーク溶接方法を説明する。 The consumable gas shielded arc welding method according to the present invention will be explained below based on the drawings.
第２図には、本発明に用いられる溶接送置が示
されている。第２図において、消耗性電極１０と
溶接母材１２とには溶接電源１４から溶接電流Ｉ
が流されており、消耗性電極１０と溶接母材１２
との間にはアーク１６が発生する。溶接電源１４
は、三相電源１８からの三相交流電流を直流に変
換するコンバータ２０・２２を備えている。消耗
性電極１０にはコンバータ２０の正極とコンバー
タ２２の負極とが接続されており、溶接母材１２
にはコンバータ２０の負極とコンバータ２２の正
極とが接続されている。そしてコンバータ２０・
２２は制御器２４にて制御されている。 FIG. 2 shows a welding station used in the present invention. In FIG. 2, a welding current I is applied to the consumable electrode 10 and the welding base material 12 from a welding power source 14.
is flowing, and the consumable electrode 10 and the welding base material 12
An arc 16 occurs between the two. Welding power source 14
is equipped with converters 20 and 22 that convert three-phase alternating current from three-phase power supply 18 into direct current. A positive electrode of a converter 20 and a negative electrode of a converter 22 are connected to the consumable electrode 10, and the welding base material 12 is connected to the consumable electrode 10.
The negative electrode of converter 20 and the positive electrode of converter 22 are connected to. And converter 20・
22 is controlled by a controller 24.
制御器２４は第３図に示されたような溶接電流
Ｉを流すために、コンバータ２０・２２の制御を
行なう。すなわち、制御器２４が外部からの溶接
開始指令によりコンバータ２０をオンさせ逆極性
溶接電流Ｉ＝ＩRをT1の時間だけ流し、時刻T1と
なつたときにコンバータ２０をオフさせると同時
にコンバータ２２をオンさせて正極性溶接電流Ｉ
＝ＩFをT2の時間だけ流す。したがつて、消耗性
電極１０と溶接母材１２との間には最初に電流Ｉ
Rによる逆極性アークの放電が行なわれ、次に溶
接電流Ｉ＝ＩFによる正極性アークの放電が行な
われる。以上のサイクルが次々と行なわれて、ア
ーク溶接が続けられていく。 A controller 24 controls converters 20 and 22 to flow a welding current I as shown in FIG. That is, the controller 24 turns on the converter 20 in response to an external welding start command, causes the reverse polarity welding current I=I R to flow for a time T1 , and turns off the converter 20 at time T1 , and at the same time turns the converter 20 on. 22 to turn on the positive welding current I.
= Flow I F for the time T 2 . Therefore, there is initially a current I between the consumable electrode 10 and the weld base metal 12.
A reverse polarity arc is discharged by R , and then a positive polarity arc is discharged by a welding current I= IF . The above cycles are performed one after another, and arc welding continues.
なお、逆極性アークによる溶接を正極性アーク
による溶接に先がけて最初に行なつているのは、
逆極性アークによる溶接の場合はアーク始動性が
良いので溶接開始直後における溶接不良が防止で
きるからである。 Note that welding with a reverse polarity arc is performed first before welding with a positive polarity arc.
This is because in the case of welding using a reverse polarity arc, the arc startability is good, so welding defects immediately after welding is started can be prevented.
第４図には正極性アークによる溶接の場合と逆
極性アークによる溶接の場合とについて消耗性電
極１０の送給量（縦軸）と溶接電流Ｉ（横軸）と
の関係を比較して示したものである。 Figure 4 shows a comparison of the relationship between the feed rate of the consumable electrode 10 (vertical axis) and the welding current I (horizontal axis) for welding with a positive polarity arc and welding with a reverse polarity arc. It is something that
この第４図から溶接電流ＩFによる正極性アー
ク溶接状態における消耗性電極１０の供給量は、
溶接電流ＩRによる逆極性アーク溶接状態におけ
る消耗性電極１０の供給量より多いことが判る。 From this FIG. 4, the supply amount of the consumable electrode 10 in the positive polarity arc welding state with the welding current I F is as follows:
It can be seen that the supply amount of the consumable electrode 10 is larger than that in the reverse polarity arc welding state using the welding current I R .
溶接電流ＩF＝ＩRの場合では、正極性アーク溶
接状態のときの消耗性電極１０の送給量は逆極性
アーク溶接状態のときの消耗性電極１０の送給量
の1.5倍程度となることが知られており、このこ
とは消耗性電極１０の送給量が一定の場合には、
ＩＦ／ＩＲ＝１／１．５程度となることを示していると
理解でき
る。 When the welding current I F =I R , the feed rate of the consumable electrode 10 during positive polarity arc welding is approximately 1.5 times the feed rate of the consumable electrode 10 during reverse polarity arc welding. This is known, and this means that when the feed rate of the consumable electrode 10 is constant,
It can be understood that this shows that I F /I R = about 1/1.5.
したがつて、ＩＦ／ＩＲ＝１／１．５の場合（例えば
ＩR＝240A
としＩF＝160Aとした場合）には消耗性電極１０
の送給量は正極性アーク溶接状態の場合でもほと
んど変化しないことになる。又ＩＦ／ＩＲ＝１／１．５
となると
きは消耗性電極１０への入熱は逆極性アークによ
る溶接の場合より正極性アークによる溶接の場合
の方がかなり小さいこととなる。 Therefore, when I F /I R = 1/1.5 (for example, I R = 240 A and I F = 160 A), the consumable electrode 10
This means that the feed rate hardly changes even in positive polarity arc welding. Also, I F /I R =1/1.5
When , the heat input to the consumable electrode 10 is considerably smaller in the case of welding with a positive polarity arc than in the case of welding with a reverse polarity arc.
以上の説明から本発明のように逆極性アークに
よる溶接と正極性アークによる溶接とを交互に行
なうこととすれば、正極性アークによる溶接を行
なうときの消耗性電極１０の送給量を逆極性アー
クによる溶接を行なうときの消耗性電極１０の送
給量と等しくすることができあるいは任意に設定
できるので溶接速度を従来の場合と比較して増加
させることができる。そして、正極性アークによ
る溶接を行なつているときにおける入熱は逆極性
アークによる溶接を行なつているときにおける入
熱よりかなり小さいので、正極性アークによる溶
接を行なつているときには溶融池の冷却作用が生
じ溶融池の凝固が行なわれて、溶湯の垂れ落ちを
生ずることがない。 From the above explanation, if welding with a reverse polarity arc and welding with a positive polarity arc are performed alternately as in the present invention, the feed rate of the consumable electrode 10 when performing welding with a positive polarity arc is set to the reverse polarity. Since the feeding amount of the consumable electrode 10 can be made equal to the feeding amount of the consumable electrode 10 when performing arc welding, or can be set arbitrarily, the welding speed can be increased compared to the conventional case. The heat input when welding with a positive polarity arc is considerably smaller than the heat input when welding with a reverse polarity arc, so when welding with a positive polarity arc, the molten pool A cooling effect occurs and the molten pool solidifies, so that the molten metal does not drip.
要するに、本発明によれば、逆極性アークによ
る溶接のときに入熱を大きくし、溶接速度を高く
して良好な溶接を行ない、次に正極性アークによ
る溶接に切り換えることによつて溶接速度をその
まま維持しながら溶融池の凝固を行なつて溶湯の
垂れ落ちを防止することができる。 In short, according to the present invention, when welding with a reverse polarity arc, the heat input is increased and the welding speed is increased to achieve good welding, and then the welding speed is increased by switching to welding with a positive polarity arc. By solidifying the molten pool while maintaining it as it is, it is possible to prevent the molten metal from dripping.
なお、正極性アークによる溶接の場合には入熱
が小さいので融合不良が生ずるという不安がある
が、この場合には溶接母材１２が十分に加熱され
ていれば融合不良を生じることがない。そこで、
正極性アークによる溶接の期間を短くしあるいは
逆極性アークによる溶接の期間を長くし、正極性
アークによる溶接のときの溶接母材１２の温度を
十分高めることとする。このようにすれば、正極
性アークによる溶接のときの溶接不良が生ずるこ
とがない。そして、このときの逆極性アークによ
る溶接継続期間と正極性アークによる溶接継続期
間とは３秒以内であることが消耗性電極式ガスシ
ールドアーク溶接法では好ましい、という試験結
果を得ている。したがつて、種々の溶接条件に応
じて３秒以内に逆極性アークによる溶接期間と正
極性アークによる溶接期間とを同時にあるいは別
別に設定することにより、良好な溶接結果を得る
ことができる。 In the case of welding using a positive polarity arc, there is a concern that poor fusion will occur because the heat input is small, but in this case, if the welding base material 12 is sufficiently heated, no defective fusion will occur. Therefore,
The period of welding with a positive polarity arc is shortened or the period of welding with a reverse polarity arc is lengthened to sufficiently raise the temperature of the weld base material 12 during welding with a positive polarity arc. In this way, welding defects will not occur during welding using a positive polarity arc. A test result has been obtained that it is preferable in the consumable electrode type gas shield arc welding method that the welding duration using the reverse polarity arc and the welding duration using the positive polarity arc be within 3 seconds. Therefore, good welding results can be obtained by setting the welding period using the reverse polarity arc and the welding period using the positive polarity arc simultaneously or separately within 3 seconds according to various welding conditions.
以上説明したように、本発明によれば、溶湯の
垂れ落ちが生ぜず、かつ溶接速度が高い消耗性電
極式ガスシールドアーク溶接方法を提供すること
ができる。 As described above, according to the present invention, it is possible to provide a consumable electrode type gas shield arc welding method that does not cause dripping of molten metal and has a high welding speed.
第１図は従来の消耗性電極式ガスシールドアー
ク溶接方法における溶接電流の波形図、第２図は
本発明に係る消耗性電極式シールドアーク溶接方
法において用いられる溶接装置のブロツク図、第
３図は本発明に係る消耗性電極式ガスシールドア
ーク溶接方法における溶接電流の波形図、第４図
は消耗性電極の送給量と溶接電流との関係を示す
特性図である。各図中同一部材には同一符号を付
し、１０は消耗性電極、１２は溶接母材、１４は
溶接電源、１６はアーク、２０・２２はコンバー
タ、２４は制御器、Ｉは溶接電流、ＩFは正極性
アークのときの溶接電流、ＩRは逆極性アークの
ときの溶接電流である。
Fig. 1 is a waveform diagram of welding current in a conventional consumable electrode type gas shielded arc welding method, Fig. 2 is a block diagram of a welding device used in the consumable electrode type shielded arc welding method according to the present invention, and Fig. 3 4 is a waveform diagram of welding current in the consumable electrode type gas-shielded arc welding method according to the present invention, and FIG. 4 is a characteristic diagram showing the relationship between the feed rate of the consumable electrode and the welding current. In each figure, the same members are given the same symbols, 10 is a consumable electrode, 12 is a welding base material, 14 is a welding power source, 16 is an arc, 20 and 22 are converters, 24 is a controller, I is a welding current, I F is the welding current for positive polarity arc, and I R is the welding current for reverse polarity arc.
Claims (1)
させて溶接母材の溶接を行なう消耗電極式ガスシ
ールドアーク溶接方法において、消耗性電極を正
極とし溶接母材を負極として消耗性電極と溶接母
材との間で逆極性アークを発生させ大電流により
溶融池の形成を行なう逆極性アーク溶接状態と、
消耗性電極を負極とし溶接母材を正極として消耗
性電極と溶接母材との間で正極性アークを発生さ
せ小電流により溶融池の冷却作用を行なう正極性
アーク溶接状態と、を交互に繰り返して溶接を行
うことを特徴とする消耗性電極式ガスシールドア
ーク溶接方法。1. In the consumable electrode type gas shielded arc welding method in which an arc is generated between the consumable electrode and the welding base material to weld the welding base metal, the consumable electrode is used as the positive electrode and the welding base material is the negative electrode. a reverse polarity arc welding state in which a reverse polarity arc is generated between the weld base metal and a molten pool is formed by a large current;
A positive arc welding state in which the consumable electrode is the negative electrode and the weld base metal is the positive pole generates a positive arc between the consumable electrode and the weld base metal to cool the molten pool with a small current is repeated alternately. A consumable electrode gas-shielded arc welding method characterized by welding using a consumable electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3536280A JPS56131080A (en) | 1980-03-19 | 1980-03-19 | Gas shielded arc welding method on consumable electrode system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3536280A JPS56131080A (en) | 1980-03-19 | 1980-03-19 | Gas shielded arc welding method on consumable electrode system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56131080A JPS56131080A (en) | 1981-10-14 |
| JPS626908B2 true JPS626908B2 (en) | 1987-02-14 |
Family
ID=12439772
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3536280A Granted JPS56131080A (en) | 1980-03-19 | 1980-03-19 | Gas shielded arc welding method on consumable electrode system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56131080A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5945078A (en) * | 1982-09-06 | 1984-03-13 | Toyota Motor Corp | Polarity switching type arc welding |
| JP2710939B2 (en) * | 1988-01-28 | 1998-02-10 | 株式会社神戸製鋼所 | Consumable electrode type bipolar arc welding method |
| JP2614892B2 (en) * | 1988-03-31 | 1997-05-28 | 株式会社神戸製鋼所 | Gas shielded arc welding method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55126384A (en) * | 1979-03-22 | 1980-09-30 | Nippon Steel Corp | Consumable electrode process arc welding method for steel |
-
1980
- 1980-03-19 JP JP3536280A patent/JPS56131080A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55126384A (en) * | 1979-03-22 | 1980-09-30 | Nippon Steel Corp | Consumable electrode process arc welding method for steel |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56131080A (en) | 1981-10-14 |
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