JPH02255283A - Method for controlling welding of seam welded pipe - Google Patents
Method for controlling welding of seam welded pipeInfo
- Publication number
- JPH02255283A JPH02255283A JP7938189A JP7938189A JPH02255283A JP H02255283 A JPH02255283 A JP H02255283A JP 7938189 A JP7938189 A JP 7938189A JP 7938189 A JP7938189 A JP 7938189A JP H02255283 A JPH02255283 A JP H02255283A
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- 238000003466 welding Methods 0.000 title claims abstract description 85
- 238000000034 method Methods 0.000 title claims description 17
- 230000010355 oscillation Effects 0.000 claims abstract description 20
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 230000005540 biological transmission Effects 0.000 abstract description 5
- 239000000463 material Substances 0.000 abstract description 5
- 230000001105 regulatory effect Effects 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 11
- 238000004519 manufacturing process Methods 0.000 description 6
- 101100437161 Gallus gallus AVR6 gene Proteins 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000002123 temporal effect Effects 0.000 description 2
- NEEVCWPRIZJJRJ-LWRDCAMISA-N 5-(benzylideneamino)-6-[(e)-benzylideneamino]-2-sulfanylidene-1h-pyrimidin-4-one Chemical compound C=1C=CC=CC=1C=NC=1C(=O)NC(=S)NC=1\N=C\C1=CC=CC=C1 NEEVCWPRIZJJRJ-LWRDCAMISA-N 0.000 description 1
- 208000032369 Primary transmission Diseases 0.000 description 1
- 229910000831 Steel Inorganic materials 0.000 description 1
- 238000009529 body temperature measurement Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000003111 delayed effect Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
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- Arc Welding Control (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は高周波電縫溶接における溶接入熱の制御方法に
関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for controlling welding heat input in high frequency electric resistance welding.
溶接管の製造分野において、高周波電縫溶接は溶接速度
の速い溶接法として一般に電縫管と呼ばれる管に用いら
れている。In the field of manufacturing welded pipes, high-frequency electric resistance welding is generally used for pipes called electric resistance welded pipes as a welding method with a high welding speed.
第３図は電縫管の製造方法、例えば高周波誘導溶接法に
よる溶接造管工程の一例を示す模式図である。FIG. 3 is a schematic diagram showing an example of a welding pipe manufacturing process using a method of manufacturing an electric resistance welded pipe, for example, a high frequency induction welding method.
まず、図示しない成形ロール群によって管状に成形され
、矢符方向へ搬送される帯板１の突合わせ面２は、スク
イズロール３によって突合わせられ、衝合部を頂点とす
る楔状を呈する。スクイズロール３の搬送方向上流側に
配備され、帯板１を囲、するワークコイル４には高周波
電圧が印加され、その電流によって生じる誘導電流が楔
状をなす突合わせ面２に沿って流れる。この高周波誘導
電流により、突合わせ面２が加熱され、樹形状の頂点、
即ち溶接点が溶接温度に達し、スクイズロール３により
加圧溶接される。First, the abutting surfaces 2 of the strip plate 1, which is formed into a tubular shape by a group of forming rolls (not shown) and conveyed in the direction of the arrow, are abutted by the squeeze rolls 3, forming a wedge shape with the abutting portion as the apex. A high frequency voltage is applied to a work coil 4 disposed on the upstream side of the squeeze roll 3 in the conveyance direction and surrounding the strip 1, and an induced current generated by the current flows along the wedge-shaped abutment surface 2. This high-frequency induced current heats the abutting surface 2, and the apex of the tree shape,
That is, the welding point reaches the welding temperature and is welded under pressure by the squeeze roll 3.
このような電縫溶接においては適正な溶接入熱が確保さ
れないと溶接品質が低下してしまう。そこで従来、種々
の試みがなされており、その代表的なものとして、溶接
部の温度を測定し、溶接温度が一定範囲に維持されるよ
うに溶接入熱を制御する、所謂温度フィードバンクの考
え方があり、例えば特開昭５８〜２５８８２号公報、又
は特開昭５７−１９５５８７号公報等に提案されている
。In such electric resistance welding, if appropriate welding heat input is not ensured, welding quality will deteriorate. Therefore, various attempts have been made in the past, one of which is the so-called temperature feed bank concept, which measures the temperature of the weld zone and controls the welding heat input so that the welding temperature is maintained within a certain range. These methods have been proposed, for example, in JP-A-58-25882 and JP-A-57-195587.
第４図は高周波電縫溶接装置の代表的な回路図であり、
電源部２０．昇圧部３０９発振部４０．溶接部５０及び
温度測定部６０に大別される。電源部２０においては、
交流電源５から印加される交流電圧がＡＶＲ６にて電圧
調整された後、ＳＣＲ７にて整流され昇圧部３０の昇圧
トランス８へ与えられる。Figure 4 is a typical circuit diagram of a high frequency electric resistance welding device.
Power supply section 20. Boosting section 309 oscillating section 40. It is roughly divided into a welding section 50 and a temperature measuring section 60. In the power supply section 20,
After the AC voltage applied from the AC power supply 5 is voltage-adjusted by the AVR 6, it is rectified by the SCR 7 and applied to the step-up transformer 8 of the step-up section 30.
昇圧トランス８にて昇圧された交流電圧は整流器９にて
直流電圧に変換され、発振部４０の発振管１０へ与えら
れる。発振部４０では、直流電圧が再び交流電圧に変換
され、ＣＴ）ランス１１のコイルｌｌａを通じて溶接部
５０のワークコイル４に高周波電流を発生させる。The AC voltage boosted by the step-up transformer 8 is converted into a DC voltage by the rectifier 9, and is applied to the oscillation tube 10 of the oscillation section 40. In the oscillating section 40, the DC voltage is converted back into an AC voltage, and a high frequency current is generated in the work coil 4 of the welding section 50 through the coil lla of the CT lance 11.
温度測定部６０では電縫管１の溶接点の温度を温度計１
２にて測定しており、この測定結果に基づいてＡＶＲ６
の電圧が調整され、溶接温度が制御される。The temperature measurement unit 60 measures the temperature at the welding point of the ERW pipe 1 with a thermometer 1.
2, and based on this measurement result, AVR6
voltage is adjusted to control the welding temperature.
第５図は溶接温度を制御する為の温度フィードバックの
実施例を示すブロック線図である。目標入熱量、即ち目
標となる溶接温度と、実際の温度計出力との偏差は補償
要素２１へ入力され、その出力を入力してＡＶＩ？ ６
はゲインに、を乗じる特性２２により電圧■１を発生す
る。ＳＣＲ７はゲインに２を乗じる特性２３により電圧
■１を整流した電圧ｖ２を発生し、これを入力して昇圧
トランス８は一次おくれの伝達要素２４によりプレート
電圧Ｅｐを発生する。プレート電圧Ｅｐは発振部４０の
発振回路４０ａへ入力され、発振回路４０ａはゲインに
３を乗じる特性２５により溶接電流Ｉを発生する。この
溶接電流Ｉを入力して溶接部５０はゲインに４を乗じる
特性２６により温度Ｔを発生する。そして温度計１１は
温度Ｔを入力して一次おくれの伝達要素２７により前記
温度計出力を発生する。FIG. 5 is a block diagram showing an embodiment of temperature feedback for controlling welding temperature. The deviation between the target heat input amount, that is, the target welding temperature, and the actual thermometer output is input to the compensation element 21, and the output is input to AVI? 6
generates voltage ■1 by the characteristic 22 of multiplying the gain by . The SCR 7 generates a voltage v2 which is obtained by rectifying the voltage 1 according to the characteristic 23 of multiplying the gain by 2, and upon inputting this voltage, the step-up transformer 8 generates a plate voltage Ep through the primary delayed transmission element 24. The plate voltage Ep is input to the oscillation circuit 40a of the oscillation section 40, and the oscillation circuit 40a generates the welding current I according to the characteristic 25 of multiplying the gain by 3. When this welding current I is input, the welding part 50 generates a temperature T based on the characteristic 26 of multiplying the gain by 4. Then, the thermometer 11 receives the temperature T and generates the thermometer output through the first-order delay transmission element 27.
ところで、溶接品質を安定して保つ為には、溶接温度を
一定に保つことが最も直接的で有効な方法であるが、溶
接温度は溶接部の負荷の変動（母材端面の肉厚、突合せ
形状、インピーダの効率変化等）により一定しない。そ
こでこれを一定に制御する為に上述した如く、温度フィ
ードバックが試みられてきたが、溶接温度を測定する際
に溶接部付近の雰囲気等の影響により、温度計の出力信
号に雑音が含まれてしまうことは避けられなかった。By the way, in order to maintain stable welding quality, the most direct and effective method is to keep the welding temperature constant; It varies depending on the shape, impeder efficiency change, etc.). In order to control this constant, temperature feedback has been attempted as described above, but when measuring the welding temperature, the output signal of the thermometer contains noise due to the influence of the atmosphere near the welding part. It was inevitable that I would put it away.
この為、温度フィードバックを施した閉ループ系の連応
性を高めようとすると、温度計の出力信号に含まれた雑
音が外乱となり、安定した制御が実現できなくなるので
、止むを得ず連応性を犠牲にした制御を行う必要があっ
た。Therefore, if you try to improve the connectivity of a closed-loop system with temperature feedback, the noise contained in the thermometer's output signal will become a disturbance, making it impossible to achieve stable control, so you will have no choice but to sacrifice connectivity. It was necessary to perform controlled controls.
本発明は斯かる事情に鑑みてなされたものであり、高周
波電縫溶接を行う鋼管製造設備において本発明者が知見
した事実、つまり、電縫管の溶接温度を制御する上で、
その制御系の動的特性を支配しているのが昇圧部のトラ
ンスと、温度計とであるということに基づき、最も直接
的で有効な手段である温度フィードバックという考えを
継承した上でこれの連応性を高めることが可能な電縫管
の溶接制御方法の提供を目的とする。The present invention has been made in view of the above circumstances, and the present inventor has discovered the facts in steel pipe manufacturing equipment that performs high-frequency ERW welding, that is, in controlling the welding temperature of ERW pipes,
Based on the fact that the dynamic characteristics of the control system are controlled by the transformer in the step-up section and the thermometer, we inherited the idea of temperature feedback, which is the most direct and effective means, and developed this system. The purpose of the present invention is to provide a welding control method for electric resistance welded pipes that can improve coordination.
Ｃ課題を解決するための手段〕
本発明に係る電縫管の溶接制御方法は、溶接温度を検出
し、これを目標温度に制御すべく、高周波発振回路に印
加する溶接電圧を調節して電縫管を溶接する電縫管の溶
接制御方法において、前記高周波発振回路に通流される
電流を検出し、これの検出結果と、前記溶接温度の検出
結果とに基づいて前記溶接電圧を調節することを特徴と
する。Means for Solving Problem C] The welding control method for an ERW pipe according to the present invention detects the welding temperature and adjusts the welding voltage applied to a high frequency oscillation circuit to control the welding temperature to a target temperature. In the welding control method of an electric resistance welded pipe for welding a sewn pipe, a current flowing through the high frequency oscillation circuit is detected, and the welding voltage is adjusted based on the detection result of this and the detection result of the welding temperature. It is characterized by
電縫管は、高周波発振回路に通流される電流値の検出結
果と、溶接温度の検出結果とに基づいて高周波発振回路
に印加される電圧が調節されて溶接される。The electric resistance welded tube is welded by adjusting the voltage applied to the high frequency oscillation circuit based on the detection result of the current value passed through the high frequency oscillation circuit and the detection result of the welding temperature.
（実施例〕
以下、本発明をその実施例を示す図面に基づき具体的に
説明する。第１図は本発明に係る電縫管の溶接制御方法
を実施する装置構成を示す回路図、第２図はその制御内
容を示すブロック線図であり、装置の構成は第４図に示
した従来例と略等しく、一致するものについては同一符
号を付してあり、説明を省略する。図中１５は、発振部
５に通流される溶接電流を検出する電流計であり、発振
管１０のプレート電流を検出するようになっている。(Example) Hereinafter, the present invention will be specifically explained based on drawings showing examples thereof. Fig. 1 is a circuit diagram showing the configuration of an apparatus for carrying out the welding control method for an electric resistance welded pipe according to the present invention; The figure is a block diagram showing the control contents, and the configuration of the device is approximately the same as the conventional example shown in FIG. is an ammeter that detects the welding current flowing through the oscillating section 5, and is designed to detect the plate current of the oscillating tube 10.
次に第２図を用いて制御内容を説明すると、目標入熱量
と、温度計出力との偏差は定常偏差を零にする為の積分
要素３１へ入力してあり、その出力と、特性２８により
フィードバンクゲインＧ１を乗じた溶接電流■及び特性
２９によりフィードバックゲインＧ２を乗じた温度計出
力との偏差がＡＶＲ６へ入力しである。これを入力して
ＡＶＲ６はゲインに１を乗しる特性２２により電圧■１
を発生する。Next, to explain the control contents using Fig. 2, the deviation between the target heat input amount and the thermometer output is input to the integral element 31 to make the steady deviation zero, and the output and characteristic 28 are The deviation between the welding current (2) multiplied by the feed bank gain G1 and the thermometer output multiplied by the feedback gain G2 according to characteristic 29 is input to the AVR 6. By inputting this, the AVR6 has a voltage of 1 due to the characteristic 22 of multiplying the gain by 1.
occurs.
ＳＣＲ７はゲインに２を乗じる特性２３により電圧■、
を整流した電圧■２を発生し、これを入力して昇圧トラ
ンス８は一次お（れの伝達要素２４によりプレート電圧
Ｅｐを発生する。プレート電圧Ｅｐは発振部４０の発振
回路４０ａへ人力され、発振回路４０ａはゲインに３を
乗じる特性２５により溶接電流■を発生する。この溶接
電流Ｉは溶接部５０へ入力しである一方、前記特性２８
によりＡＶＲ６ヘフイードバンクしである。溶接部５０
はゲインに４を乗じる特性２６により温度Ｔを発生する
。そして温度計１１は温度Ｔを入力して一次おくれの伝
達要素２７により前記温度計出力を発生する。SCR7 has a voltage ■, due to the characteristic 23 that multiplies the gain by 2.
Rectified voltage (2) is generated, and upon inputting this voltage, the step-up transformer 8 generates a plate voltage Ep through its primary transmission element 24.The plate voltage Ep is manually inputted to the oscillation circuit 40a of the oscillation section 40, The oscillation circuit 40a generates a welding current (■) according to the characteristic 25 in which the gain is multiplied by 3.This welding current I is input to the welding section 50, while the above-mentioned characteristic 28
This is the AVR6 feed bank. Welding part 50
generates the temperature T by the characteristic 26 of multiplying the gain by 4. Then, the thermometer 11 receives the temperature T and generates the thermometer output through the first-order delay transmission element 27.
なお、溶接電流■は実際に電縫管の被加熱部の端面付近
を流れる全電流を使用するのが望ましいが、測定が困難
ということもあり、本実施例に示すように発振管１０の
プレート電流以外にも発振回路４０ａ中のＡ、又はＢの
地点の電流によって代表しても良いし、あるいは何らか
の形で溶接部の負荷変動を代表できる信号（例えば発振
周波数の変動）で代替することもできる。It is desirable to use the entire current that actually flows near the end face of the heated part of the ERW tube as the welding current (■), but since it is difficult to measure, as shown in this example, the plate of the oscillation tube 10 is In addition to the current, it may be represented by the current at point A or B in the oscillation circuit 40a, or it may be replaced by a signal that can represent the load fluctuation of the welding part in some way (for example, a fluctuation in the oscillation frequency). can.
第６図＋ａｌ （ｂ）は夫々、小径電縫管ミルの溶接時
における溶接温度及び溶接電圧（制御電圧）の時間的変
化を示すグラフであり、第６図（ａｌは従来の温度のみ
の単独フィードバックによる制御例、また第６図（ｂｌ
は本発明方法による溶接電流を付加したフィードバック
による制御例を示し、両者共、ａの時点で材質の変更を
行っている。図中太線は溶接温度を、細線は溶接電圧を
、また第６図（ｂｌの破線は溶接電流を夫々示しである
。Figure 6 + al (b) is a graph showing the temporal changes in welding temperature and welding voltage (control voltage) during welding of a small diameter ERW tube mill, respectively; An example of control by feedback is also shown in Fig. 6 (bl
1 shows an example of control by feedback with addition of welding current according to the method of the present invention, and in both cases, the material is changed at point a. In the figure, the thick line indicates the welding temperature, the thin line indicates the welding voltage, and the broken line in FIG. 6 (bl) indicates the welding current.
まず、従来例にあっては材質の変更後、溶接温度が目標
温度の範囲内に回復するのに約１．５秒要した。これに
対し、本発明方法においては回復時間が１秒以内に短縮
されており、連応性が大きく向上されていることが分か
る。First, in the conventional example, after changing the material, it took about 1.5 seconds for the welding temperature to recover within the target temperature range. On the other hand, in the method of the present invention, the recovery time is shortened to less than 1 second, and it can be seen that the continuity is greatly improved.
以上の如く本発明方法においては、従来の温度信号のみ
の単独フィードバックの制御方法に溶接電流をフィード
バンク信号として付加することにより、温度計による測
温の際に加えられる外乱の影響を受けずに安定した制御
を行え、また溶接電流の信号が温度計によって積分され
る以前の信号である為、被溶接材の材質変化等による溶
接部の電気的負荷の変化等の外乱に対しても安定性を損
なうことなく、連応性を高められる。As described above, in the method of the present invention, by adding the welding current as a feedbank signal to the conventional control method of independent feedback of only the temperature signal, it is possible to eliminate the influence of disturbances applied when measuring temperature with a thermometer. Stable control can be performed, and since the welding current signal is a signal before being integrated by a thermometer, it is stable against disturbances such as changes in the electrical load of the welding part due to changes in the material of the welded material etc. It is possible to improve coordination without impairing the
この結果、溶接不良を低減でき、溶接品質及び製管歩留
の向上が図れる等、本発明は優れた効果を奏する。As a result, the present invention has excellent effects such as reducing welding defects and improving welding quality and pipe manufacturing yield.
第１図は本発明に係る電縫管の溶接制御方法を実施する
装置の回路図、第２図はその制御内容を示すブロック線
図、第３図は溶接造管工程の一例を示す模式図、第４図
は従来の高周波電縫溶接装置の回路図、第５図は従来の
制御内容を示すブロック線図、第６図は小径電縫管ミル
の溶接時における溶接温度、溶接電圧及び溶接電流の時
間的変化を示すグラフである。
１・・・電縫管 ４・・・ワークコイル ６・・・ＡＶ
Ｉ？ ７・・・ＳＣＲ８・・・昇圧トランス ９・・
・発振管 １２・・・温度計 １５・・・電流計 ４０
・・・発振部 ４０ａ・・・高周波発振回路
特 許 出願人 住友金属工業株式会社代理人 弁理
士 河 野 登 夫図
（ｂ）Fig. 1 is a circuit diagram of a device implementing the welding control method for electric resistance welded pipes according to the present invention, Fig. 2 is a block diagram showing the control contents, and Fig. 3 is a schematic diagram showing an example of the welding pipe manufacturing process. , Fig. 4 is a circuit diagram of a conventional high-frequency electric resistance welding device, Fig. 5 is a block diagram showing conventional control contents, and Fig. 6 shows welding temperature, welding voltage, and welding during welding of a small diameter electric resistance welding pipe mill. It is a graph showing temporal changes in current. 1... ERW pipe 4... Work coil 6... AV
I? 7...SCR8...Step-up transformer 9...
・Oscillator tube 12...Thermometer 15...Ammeter 40
...Oscillating part 40a...High frequency oscillation circuit patent Applicant Sumitomo Metal Industries Co., Ltd. Agent Patent attorney Noboru Kono Diagram (b)
Claims (1)
高周波発振回路に印加する溶接電圧を調節して電縫管を
溶接する電縫管の溶接制御方法において、 前記高周波発振回路に通流される電流を検 出し、これの検出結果と、前記溶接温度の検出結果とに
基づいて前記溶接電圧を調節すること を特徴とする電縫管の溶接制御方法。[Claims] 1. To detect welding temperature and control it to a target temperature,
A welding control method for an ERW pipe in which the welding voltage applied to a high frequency oscillation circuit is adjusted to weld the ERW pipe includes detecting a current flowing through the high frequency oscillation circuit, and combining the detection result with the welding temperature. A method for controlling welding of an electric resistance welded pipe, characterized in that the welding voltage is adjusted based on a detection result.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7938189A JPH02255283A (en) | 1989-03-29 | 1989-03-29 | Method for controlling welding of seam welded pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7938189A JPH02255283A (en) | 1989-03-29 | 1989-03-29 | Method for controlling welding of seam welded pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02255283A true JPH02255283A (en) | 1990-10-16 |
Family
ID=13688293
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7938189A Pending JPH02255283A (en) | 1989-03-29 | 1989-03-29 | Method for controlling welding of seam welded pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02255283A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012505528A (en) * | 2008-10-07 | 2012-03-01 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Power semiconductor device adaptive cooling assembly |
-
1989
- 1989-03-29 JP JP7938189A patent/JPH02255283A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2012505528A (en) * | 2008-10-07 | 2012-03-01 | コーニンクレッカ フィリップス エレクトロニクス エヌ ヴィ | Power semiconductor device adaptive cooling assembly |
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