JPH0558840B2 - - Google Patents
Info
- Publication number
- JPH0558840B2 JPH0558840B2 JP63312682A JP31268288A JPH0558840B2 JP H0558840 B2 JPH0558840 B2 JP H0558840B2 JP 63312682 A JP63312682 A JP 63312682A JP 31268288 A JP31268288 A JP 31268288A JP H0558840 B2 JPH0558840 B2 JP H0558840B2
- Authority
- JP
- Japan
- Prior art keywords
- pipe
- welding
- upset
- welded
- electric resistance
- 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
- 238000000034 method Methods 0.000 claims description 30
- 239000002184 metal Substances 0.000 claims description 22
- 238000004519 manufacturing process Methods 0.000 claims description 15
- 238000003466 welding Methods 0.000 description 30
- 238000005304 joining Methods 0.000 description 5
- 229910000831 Steel Inorganic materials 0.000 description 4
- 239000002131 composite material Substances 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- 239000010959 steel Substances 0.000 description 4
- 238000005520 cutting process Methods 0.000 description 3
- 238000010438 heat treatment Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 238000007711 solidification Methods 0.000 description 3
- 230000008023 solidification Effects 0.000 description 3
- 229910000746 Structural steel Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000012535 impurity Substances 0.000 description 2
- 238000011144 upstream manufacturing Methods 0.000 description 2
- 229910000851 Alloy steel Inorganic materials 0.000 description 1
- 229910000975 Carbon steel Inorganic materials 0.000 description 1
- 239000011324 bead Substances 0.000 description 1
- 238000005452 bending Methods 0.000 description 1
- 239000010962 carbon steel Substances 0.000 description 1
- 230000015271 coagulation Effects 0.000 description 1
- 238000005345 coagulation Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000007730 finishing process Methods 0.000 description 1
- 230000004927 fusion Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
Landscapes
- Laser Beam Processing (AREA)
Description
〔産業上の利用分野〕
本発明は、電縫管の製造方法に係り、特に高強
度鋼管及びＳ添加が必要な快削性構造用鋼管を電
縫溶接で製造する場合の方法に関するものであ
る。
〔従来の技術及び発明が解決しようとする課題〕
電縫溶接方法は、一般に数十〜数百ｋHzの高周
波電流を用いて、誘導方式又は直接通電方式によ
り、オープンパイプの相対向する被接合面を加熱
溶融させて接合を得る方法であり、溶接管の製管
方法のなかで最も高能率な方法であるので、中小
径の金属管の製造に主として汎用されている。
しかし、電縫溶接においては、オープンパイプ
の相対向する被接合面に高周波の大電流が流れる
ために、溶融金属にはこの大電流による強力な電
磁力が作用して、溶融金属の被接合面からの排出
現象及び被接合面での凝固の不安定現象が生じ
る。従つて、電縫溶接では、アーク溶接等の溶融
溶接では不必要であるアプセツトが必要不可欠で
ある。
アプセツトを加えることによつて、溶融金属中
の不純物が排出されると共に被接合面での凝固が
促進されてほぼ健全な接合が可能となるが、一方
ではアプセツトによつて溶接熱影響部がメタルフ
ローにより***し、ビード部分を含むこの***部
分を切削した後に、その切削部分で鋼板の介在
物、成分偏析に起因する割れ、所謂フツククラツ
クが発生する場合がある。
このフツククラツクは、通常の炭素鋼、低合金
鋼においては、不純物元素の低減及び介在物の形
態制御（例えばCa処理）によつて防止できるの
で、特に大きな問題とならないが、高強度鋼管及
びＳ添加が必要な快削性構造用鋼管においては、
これに含有されるＳ等の成分が原因で製品の二次
加工（曲げ、偏平等）の過程で特に鋼管の外面側
にフツククラツクが多発するので、製品化が困難
であり、製品用途を限定せざるを得ないといつた
問題点があつた。
このようなアプセツトに伴う問題点を解決する
ために、アプセツトが不要であり、しかも電縫溶
接方法と同程度の溶接能率が得られる製管溶接方
法として、複合熱源を使用した溶接方法が、特開
昭56−168981号、特開昭59−30493号、特開昭61
−162279号によつて提案されている。これらに開
示された製管溶接方法は、高能率な高周波熱源
と、電磁力等の悪影響因子の無いレーザビームを
組み合わせた複合熱源製管溶接方法であつて、最
終的な溶融をレーザビームで実施しているので、
フツククラツクの原因であるアプセツトを低減で
きることが特徴である。
特開昭56−168981号公報に開示された製管溶接
方法は、複合熱源製管溶接方法に関するものであ
つて、高周波電流によつてオープンパイプの相対
向する両側エツジ部を加熱又は溶融して、その後
に、レーザビームによる照射を両側エツジ部の接
合点より下流側で管外面側から行つて最終的な接
合を得るものである。この方法の特徴は、二番目
の熱源であるレーザビームでパイプの肉厚全体を
溶融させることにあり、レーザビームの出力がわ
ずか十数kWであるので、レーザビームで照射す
る前に、第１の加熱手段（高周波電流）によつて
予熱されていたとしても、通常の電縫溶接の場合
と同等の溶接速度を得ることは困難であるといつ
た問題点があつた。
また、特開昭59−30493号公報及び特開昭61−
162279号公報に開示された複合熱源製管溶接方法
は、オープンパイプの両側エツジ部の接合点より
上流側でレーザビームを両側エツジ部のエツジ端
面に対して斜めに照射することによつてこの両側
のエツジ端面を加熱することを特徴としている
が、この方法では、高周波電流の電磁力が溶融金
属に加わることは通常の電縫溶接と同様であり、
溶接欠陥の原因となる酸化物の排出、及び凝固の
安定化の点でアプセツトが必要となり、アプセツ
トの大幅低減は不可能であるといつた問題点があ
つた。
本発明は、上記問題点に鑑みてなされたもので
あつて、従来の電縫溶接方法と同等の速度で溶接
ができ、しかもパイプの外面側に生じるメタルフ
ローの立上りを減少することができる電縫管の製
造方法を提供することを目的としている。
〔課題を解決するための手段〕
本発明に係る電縫管の溶接方法は、オープンパ
イプの相対向する両側エツジ部を加熱溶融し、ス
クイズロールにてアプセツトしつつ衝合溶接する
電縫管の製造方法において、前記スクイズロール
によるアプセツト過程にある溶接部であつて、ア
プセツトによつてメタルフローが立上り始める点
とスクイズロールの中心同士を結ぶ点との間の中
間の位置に外表面側から高エネルギービームを照
射してパイプの外表面側部分にオープンパイプの
外表面側からその肉厚の20〜80％にわたる深さの
溶融池を形成し、前記アプセツトによつて溶接部
の外表面側へのメタルフローをこの溶融池に吸収
させることを特徴とする。
〔作用〕
しかして、加熱溶融されたオープンパイプの相
対向する両側エツジ部において、その接合点より
下流側で、スクイズロールによるアプセツトによ
つて、メタルフローが立上りだすが、この部分で
レーザビームで外表面側から照射されるので、外
表面側であつて高周波電流等の影響を受けること
のない位置に溶融池が形成され、この溶融池に外
表面側のメタルフローがほとんど吸収される。
〔実施例〕
以下、本発明をその実施状態を示す図面に基づ
いて具体的に説明する。第１図は本発明に係る電
縫管の製造方法の実施状態を示す模式図、第２図
はその説明図である。図中１はオープンパイプで
あつて、オープンパイプ１はスケルプを成形ロー
ル群（図には最終段のフインパスロール５のみを
示す）に通して断面Ｕ形から両側エツジ部１ａ，
１ａが相対向する断面略Ｏ形に迄曲成してなる。
このオープンパイプ１はフインパスロール５を出
た後、その下流側に配設されたスクイズロール２
側に向かうに従つて両側エツジ部１ａ，１ａが相
互に漸近され接合点１Ａにて第３図に示すように
相互に接合され、次いで接合点１Ａとスクイズロ
ール２の軸心線と対応する位置との間における溶
接部１Ｂにて相互に衝合溶接され、管の状態でア
プセツトをかけられつつスクイズロール２，２を
経て仕上工程に向け白抜き矢符方向に移送されて
ゆくこととなるが、この間オープンパイプ１はフ
インパスロール５よりも下流側であつて、且つ接
合点１Ａよりも上流側の位置にて高周波コンタク
トチツプ３，３にて両側エツジ部１ａ，１ａを加
熱される。
そして、前記両側エツジ部１ａ，１ａが接合す
る接合点１Ａと１対のスクイズロール２，２の軸
心線を結ぶ線上の位置との間のアプセツト過程に
ある溶接部１Ｂに外表面側からレーザビーム６を
照射してパイプ１の肉厚の20〜80％をレーザビー
ム６で溶融させる。
オープンパイプ１は接合点１Ａの下流近傍位置
において第４図に示すようにアプセツトによつて
メタルフローが立上り始める。ところが、接合点
１Ａと１対のスクイズロール２，２の軸心線を結
ぶ線上の位置との中間点１Ｃで、レーザビームが
照射されて、第５図に示すようにこの箇所にパイ
プ１の外表面側に溶融池１１が生成されてこの溶
融池１１はパイプ１における１対のスクイズロー
ル２，２の軸心線を結ぶ線上の位置まで達し、こ
の溶融池１１にメタルフローが吸収されて、結果
的に第６図に示すように溶融池１１より下流側で
はパイプ１の外表面側にはメタルフローは立上が
らないこととなる。
次に表１に実際に電縫管の溶接を行つた例につ
いて示す。
[Industrial Application Field] The present invention relates to a method for manufacturing an ERW pipe, and particularly to a method for manufacturing a high-strength steel pipe and a free-cutting structural steel pipe that requires S addition by ERW welding. . [Prior art and problems to be solved by the invention] The electric resistance welding method generally uses a high frequency current of several tens to hundreds of kHz to weld opposing surfaces of open pipes by induction or direct energization. This is a method of obtaining a joint by heating and melting the metal pipes, and is the most efficient method among the pipe manufacturing methods for welded pipes, so it is mainly used for manufacturing small and medium diameter metal pipes. However, in ERW welding, a large high-frequency current flows between the opposing surfaces of the open pipe to be welded, so a strong electromagnetic force due to this large current acts on the molten metal, causing the molten metal to A discharge phenomenon and an unstable phenomenon of solidification on the surfaces to be joined occur. Therefore, in electric resistance welding, upsets, which are unnecessary in fusion welding such as arc welding, are essential. By adding an upset, impurities in the molten metal are expelled and solidification is promoted on the surfaces to be joined, making it possible to achieve a nearly sound joint. On the other hand, the upset causes the weld heat-affected zone to melt into the metal. After cutting the raised portion including the bead portion that is raised by the flow, cracks caused by inclusions and component segregation of the steel plate, so-called hook cracks, may occur in the cut portion. This hook crack is not a particularly big problem in ordinary carbon steel and low alloy steel because it can be prevented by reducing impurity elements and controlling the form of inclusions (e.g. Ca treatment), but in high-strength steel pipes and S-added For free-cutting structural steel pipes that require
Due to the components such as S contained in this, cracks often occur especially on the outer surface of the steel pipe during the secondary processing (bending, flattening) of the product, making it difficult to commercialize the product and limiting the product's use. A problem arose that I had no choice but to solve. In order to solve these problems associated with upsets, a welding method using a composite heat source has been proposed as a pipe manufacturing welding method that does not require upsets and can achieve welding efficiency comparable to that of electric resistance welding methods. 1988-168981, 1982-30493, 1982-1983
- Proposed by No. 162279. The pipe manufacturing welding method disclosed in these documents is a composite heat source pipe manufacturing welding method that combines a highly efficient high-frequency heat source and a laser beam that does not have negative factors such as electromagnetic force, and the final melting is performed by the laser beam. Because I am doing
It is characterized by being able to reduce upsets, which are the cause of hook cracks. The pipe manufacturing welding method disclosed in JP-A-56-168981 relates to a composite heat source pipe manufacturing welding method, in which opposing edges of an open pipe are heated or melted by high-frequency current. After that, irradiation with a laser beam is performed from the outer surface of the tube downstream of the joining point of the edge portions on both sides to obtain the final joint. The feature of this method is that the entire thickness of the pipe is melted using a laser beam, which is the second heat source, and since the output of the laser beam is only a few dozen kilowatts, the first Even if preheating is performed by a heating means (high frequency current), it is difficult to obtain a welding speed equivalent to that of ordinary electric resistance welding. Also, JP-A-59-30493 and JP-A-61-
The composite heat source pipe welding method disclosed in Publication No. 162279 irradiates a laser beam obliquely to the edge end faces of both edges of an open pipe upstream of the joint point of both edges. This method is characterized by heating the edge end face of the welding machine, but in this method, the electromagnetic force of the high-frequency current is applied to the molten metal in the same way as in normal electric resistance welding.
There was a problem in that upsets were necessary to discharge oxides that cause welding defects and to stabilize solidification, making it impossible to significantly reduce upsets. The present invention has been made in view of the above problems, and is an electric resistance welding method that can perform welding at the same speed as the conventional electric resistance welding method, and can reduce the rise of the metal flow that occurs on the outer surface of the pipe. The purpose of the present invention is to provide a method for manufacturing a sewn tube. [Means for Solving the Problems] A method for welding an electric resistance welded pipe according to the present invention is a method of welding an electric resistance welded pipe in which opposing edges of an open pipe are heated and melted, and the edges are butt welded while being upset with a squeeze roll. In the manufacturing method, in the welded part that is in the upsetting process by the squeeze roll, a high height is applied from the outer surface side at a position intermediate between the point where the metal flow starts to rise due to the upsetting and the point connecting the centers of the squeeze rolls. An energy beam is irradiated to form a molten pool with a depth of 20 to 80% of the wall thickness from the outside surface of the open pipe to the outside surface of the welded part by the upset. The metal flow is absorbed into this molten pool. [Function] At the opposing edges of the heated and melted open pipe, a metal flow starts to rise downstream of the joint point due to the upsetting by the squeeze roll, but this part is not affected by the laser beam. Since it is irradiated from the outer surface side, a molten pool is formed at a position on the outer surface side that is not affected by high frequency current etc., and most of the metal flow on the outer surface side is absorbed by this molten pool. [Example] Hereinafter, the present invention will be specifically described based on drawings showing the state of implementation thereof. FIG. 1 is a schematic diagram showing the implementation state of the method for manufacturing an electric resistance welded tube according to the present invention, and FIG. 2 is an explanatory diagram thereof. In the figure, reference numeral 1 denotes an open pipe, in which the skeleton is passed through a group of forming rolls (only the final stage fin pass roll 5 is shown in the figure), and the cross-section is U-shaped, with both side edge portions 1a,
1a are curved to have a substantially O-shaped cross section facing each other.
After this open pipe 1 exits the fine pass roll 5, the squeeze roll 2 disposed downstream thereof
The edge portions 1a, 1a on both sides asymptotically approach each other toward the sides and are joined to each other at a joining point 1A as shown in FIG. 3, and then at a position corresponding to the joining point 1A and the axis of the squeeze roll 2. The pipes are butt-welded to each other at the welding part 1B between the pipes, and are then transferred in the direction of the outlined arrow through squeeze rolls 2 and 2 to the finishing process while being upset in the form of a pipe. During this time, both edge portions 1a, 1a of the open pipe 1 are heated by high frequency contact chips 3, 3 at a position downstream of the fin pass roll 5 and upstream of the joining point 1A. Then, a laser beam is applied from the outer surface side to the welding part 1B which is in the upsetting process between the joining point 1A where the both side edge parts 1a and 1a are joined and a position on the line connecting the axis lines of the pair of squeeze rolls 2, 2. The laser beam 6 is irradiated to melt 20 to 80% of the wall thickness of the pipe 1. In the open pipe 1, a metal flow begins to rise due to upset as shown in FIG. 4 at a position near the downstream of the junction point 1A. However, the laser beam is irradiated at an intermediate point 1C between the joint point 1A and a position on the line connecting the axes of the pair of squeeze rolls 2, 2, and the pipe 1 is irradiated at this point as shown in FIG. A molten pool 11 is generated on the outer surface side, and this molten pool 11 reaches a position on the line connecting the axes of the pair of squeeze rolls 2, 2 in the pipe 1, and the metal flow is absorbed into this molten pool 11. As a result, as shown in FIG. 6, no metal flow rises on the outer surface of the pipe 1 on the downstream side of the molten pool 11. Next, Table 1 shows examples of actual welding of electric resistance welded pipes.
以上の如く本発明方法にあつてはアプセツト過
程にある溶接部であつて、アプセツトによつてメ
タルフローが立上り始める点とスクイズロールの
中心同士を結ぶ点との中間の位置に外表面側から
高エネルギービームを照射するから、この部分が
溶融されても、メタルフローが熱源等として用い
られる高周波電流の影響を受けることがなく、メ
タルフローの被接合面からの排出現象、或いは被
接合面での凝固の不安定現象を生じることがな
く、またこの位置に外表面側から肉厚の20〜80％
にわたる溶融池を形成することで溶融領域が拡大
し、アプセツトに際してのメタルフローの立上り
の低減が図れて良好な二次加工性が得られ、しか
も溶接速度の低下を招くこともない等本発明は優
れた効果を奏する。
As described above, in the method of the present invention, the weld is in the upsetting process, and the weld is placed at a high height from the outer surface at a position midway between the point where the metal flow starts to rise due to upsetting and the point connecting the centers of the squeeze rolls. Since the energy beam is irradiated, even if this part is melted, the metal flow will not be affected by the high frequency current used as a heat source, and the phenomenon of discharge of the metal flow from the surface to be joined or the phenomenon of metal flow at the surface to be joined will occur. It does not cause unstable coagulation, and it is possible to prevent 20 to 80% of the wall thickness from the outer surface side at this location.
The present invention has the following advantages: by forming a molten pool that extends over the welding area, the molten area expands, and the rise of the metal flow during upsetting can be reduced, resulting in good secondary workability, and without causing a decrease in welding speed. It has excellent effects.
第１図は本発明に係る電縫管の製造方法の実施
状態を示す模式図、第２図はその説明図、第３図
は第２図における−線部分端面図、第４図は
第２図における−線部分端面図、第５図は第
２図における−線部分端面図、第６図は第２
図における−線部分端面図である。
１……オープンパイプ、１Ｂ……溶接部、２…
…スクイズロール、１１……溶融池。
FIG. 1 is a schematic diagram showing the implementation state of the method for manufacturing an electric resistance welded pipe according to the present invention, FIG. 2 is an explanatory diagram thereof, FIG. 3 is an end view of the - line portion in FIG. 2, and FIG. Figure 5 is an end view of the - line part in Figure 2, Figure 6 is an end view of the - line part in Figure 2, and Figure 6 is an end view of the - line part in Figure 2.
FIG. 3 is an end view of a portion taken along the line - in the figure. 1...Open pipe, 1B...Welded part, 2...
...Squeeze roll, 11...Melting pool.
Claims (1)
加熱溶融し、スクイズロールにてアプセツトしつ
つ衝合溶接する電縫管の製造方法において、 前記スクイズロールによるアプセツト過程にあ
る溶接部であつて、アプセツトによつてメタルフ
ローが立上り始める点とスクイズロールの中心同
士を結ぶ点との間の中間の位置に外表面側から高
エネルギービームを照射してパイプの外表面側部
分にオープンパイプの外表面側からその肉厚の20
〜80％にわたる深さの溶融池を形成し、前記アプ
セツトによつて溶接部の外表面側へのメタルフロ
ーをこの溶融池に吸収させることを特徴とする電
縫管の製造方法。[Scope of Claims] 1. A method for manufacturing an electric resistance welded pipe in which opposing edge portions on both sides of an open pipe are heated and melted and butt welded while being upset with a squeeze roll, comprising: a welded portion in the upset process with the squeeze roll; A high-energy beam is irradiated from the outer surface of the pipe at a midpoint between the point where the metal flow begins to rise due to the upset and the point that connects the centers of the squeeze rolls to open the pipe on the outer surface. 20 of the wall thickness from the outside surface of the pipe
A method for manufacturing an electric resistance welded pipe, characterized in that a molten pool having a depth of ~80% is formed, and the metal flow toward the outer surface of the welded part is absorbed into the molten pool by the foregoing upset.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63312682A JPH02160189A (en) | 1988-12-09 | 1988-12-09 | Production of electric welded pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63312682A JPH02160189A (en) | 1988-12-09 | 1988-12-09 | Production of electric welded pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH02160189A JPH02160189A (en) | 1990-06-20 |
| JPH0558840B2 true JPH0558840B2 (en) | 1993-08-27 |
Family
ID=18032155
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63312682A Granted JPH02160189A (en) | 1988-12-09 | 1988-12-09 | Production of electric welded pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02160189A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0847716A (en) * | 1994-08-05 | 1996-02-20 | Nkk Corp | Manufacture of electric resistance welded steel pipe excellent in hic resistance and sscc resistance properties |
| WO2018147389A1 (en) * | 2017-02-13 | 2018-08-16 | 日新製鋼株式会社 | Method for manufacturing electroseamed metal tube, and electroseamed metal tube |
| CN108436390B (en) * | 2018-02-09 | 2019-12-17 | 方绪龙 | Method for processing shaft roller supporting plate of wheaten food processing equipment |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56168981A (en) * | 1980-05-28 | 1981-12-25 | Sumitomo Metal Ind Ltd | Production of electric welded tube |
| JPS58100982A (en) * | 1981-12-09 | 1983-06-15 | Nippon Steel Corp | Electric resistance welding using energy beam in combination |
-
1988
- 1988-12-09 JP JP63312682A patent/JPH02160189A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56168981A (en) * | 1980-05-28 | 1981-12-25 | Sumitomo Metal Ind Ltd | Production of electric welded tube |
| JPS58100982A (en) * | 1981-12-09 | 1983-06-15 | Nippon Steel Corp | Electric resistance welding using energy beam in combination |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH02160189A (en) | 1990-06-20 |
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