JP2636322B2 - Manufacturing method of ERW steel pipe with projection - Google Patents
Manufacturing method of ERW steel pipe with projectionInfo
- Publication number
- JP2636322B2 JP2636322B2 JP63105058A JP10505888A JP2636322B2 JP 2636322 B2 JP2636322 B2 JP 2636322B2 JP 63105058 A JP63105058 A JP 63105058A JP 10505888 A JP10505888 A JP 10505888A JP 2636322 B2 JP2636322 B2 JP 2636322B2
- Authority
- JP
- Japan
- Prior art keywords
- welding
- projections
- projection
- steel pipe
- erw
- 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 - Fee Related
Links
Description
【発明の詳細な説明】 ［産業上の利用分野］ 本発明は、両側縁に突起のついた突起付き熱延コイル
を使用して行う突起付き電縫鋼管の製造方法に関する。The present invention relates to a method for producing an electric resistance welded steel pipe with projections using a hot-rolled coil with projections on both side edges.
［従来技術］ 従来、突起付き鋼管の多くは、スパイラル方式により
製造されていたが、この方式では溶接速度が遅く生産性
が低いばかりでなく、小径サイズあるいは、管厚の薄い
管の製造は困難であった。このため、小径サイズあるい
は、管厚の薄い管を電縫鋼管の製造法で行うことが考え
られている。溶接面からみると、連続的に溶接を行うた
めには、溶接部の板厚が均等であることが好ましい。し
かしながら、突起付き熱延コイルは突起が断続的にある
ため、溶接部の板厚が変動し、現状の電縫鋼管の製造方
法では溶接が困難である。そこで、溶接部の板厚変動を
なくして行う方法が開発されている。その一つは、縞鋼
板素材を２組のピンチロールで挟んで、水平かつ、張力
のかけられた状態に保持しておいて、２組のピンチロー
ルの間において縞鋼板の両側縁を平坦に連続加工し、そ
の後、造管してから平坦加工部分において溶接するもの
であり（特開昭54−133468参照）、他の一つは熱間圧延
によって縞鋼板を製造する際に、被圧延材の巾より狭い
巾の縞目部を有し、かつその縞目部の両側にフリット部
を備えるロールによって両側縁が平坦な縞鋼板を圧延す
る鋼管素材用縞目付き鋼板の製造方法（特開昭54−5046
4）がある。[Prior Art] Conventionally, many steel pipes with projections have been manufactured by a spiral method. However, this method not only has a low welding speed and low productivity, but also has difficulty in manufacturing a small diameter pipe or a thin pipe. Met. For this reason, it is considered that a pipe having a small diameter or a thin pipe is manufactured by a method for manufacturing an electric resistance welded steel pipe. From the viewpoint of the welding surface, in order to perform continuous welding, it is preferable that the thickness of the welded portion is uniform. However, in the hot-rolled coil with projections, the projections are intermittent, so that the thickness of the welded portion fluctuates, and it is difficult to weld by the current method of manufacturing an electric resistance welded steel pipe. In view of this, a method has been developed in which the change in the thickness of the welded portion is eliminated. One is to sandwich the striped steel sheet material between two sets of pinch rolls, hold it horizontally and under tension, and flatten both side edges of the striped steel sheet between the two sets of pinch rolls. Continuous processing, then pipe forming, and welding at the flat processing part (see Japanese Patent Application Laid-Open No. 54-133468). A method for producing a striped steel sheet for a steel pipe material in which a striped steel sheet having a width narrower than the width of the strip and having flat sides on both sides is rolled by a roll having frit portions on both sides of the striped portion (Japanese Patent Application Laid-Open No. 54-5046
4) There is.
［発明が解決しようとする課題］ 縞鋼板の両側縁を平坦に加工するものは、ピンチロー
ルと平坦加工設備を製造ラインに設けねばならず、また
平坦加工のため造管速度を低くしなければならないか
ら、設備コストが高くなり、生産性が上がらないという
問題がある。縞目部とフラット部を有する特殊ロールを
使用して鋼管素材を製造するものは、製造する電縫管の
サイズ毎にロールを保有しなければならず、鋼管素材コ
ストが高くなるという問題がある。[Problems to be Solved by the Invention] In order to flatten both side edges of a striped steel plate, a pinch roll and flattening equipment must be provided on a production line, and the pipe forming speed must be reduced for flattening. Therefore, there is a problem that equipment costs are increased and productivity is not increased. In the case of manufacturing a steel pipe material using a special roll having a striped portion and a flat portion, a roll must be held for each size of the ERW pipe to be manufactured, and there is a problem that the cost of the steel pipe material increases. .
［課題を解決するための手段］ 本発明は、以上の問題を解決しようとするもので、両
側縁に連続した平坦部の無い突起付き熱延コイルを使用
し、外径200mmφ以上の電縫管に電縫溶接するにあたっ
て、突起付き部分のヒート係数が1.4〜3.5に、かつ呼称
板厚部分のヒート係数が2.5〜4.5の範囲に入るように溶
接入熱を制御して溶接することを特徴とする突起付き電
縫鋼管の製造方法である。但し、ヒート係数＝（溶接投
入電力）／（溶接速度×板厚）［（KV・Ａ・min/m2）×
103］であり、以下、ヒート係数の定義と単位はこれと
同様とする。[Means for Solving the Problems] The present invention is intended to solve the above problems, and uses an electric resistance welded tube having an outer diameter of 200 mmφ or more using a hot-rolled coil having projections without flat portions continuous on both side edges. It is characterized by controlling welding heat input so that the heat coefficient of the protruding part is in the range of 1.4 to 3.5 and the heat coefficient of the nominal thickness part is in the range of 2.5 to 4.5. This is a method for producing an ERW steel pipe with projections. However, heat coefficient = (welding input power) / (welding speed x plate thickness) [(KV · A · min / m 2 ) x
10 3 ], and hereinafter, the definition and unit of the heat coefficient are the same.
［作用］ 両側縁に連続した平坦部の無い突起付き熱延コイルを
使用し、外径200mmφ以上の電縫鋼管に電縫溶接するに
あたって、突起付き部分と呼称板厚部分（突起無しの部
分）について、定めるヒート係数範囲に入るように溶接
入熱を制御して溶接を行うことにより、溶接部の溶着不
良や溶け落ちがなくなる。突起付き部分のヒート係数を
1.4〜3.5としたのは、1.4未満であると溶接部の溶着不
良が発生し、3.5を越えると溶接部に溶け落ちが発生す
るからである。また、呼称板厚部分のヒート係数を2.5
〜4.5としたのは、2.5未満であると溶接部の溶着不良が
発生し、4.5を越えると溶接部に溶け落ちが発生するか
らである。[Action] Using a hot-rolled coil with projections that are continuous on both side edges and without a flat part, when performing ERW welding on an ERW steel pipe with an outer diameter of 200 mmφ or more, a portion with a projection and a plate thickness portion (a portion without a projection) By performing the welding while controlling the welding heat input so as to fall within the predetermined heat coefficient range, poor welding and burn-through of the welded portion are eliminated. Heat coefficient of the part with protrusion
The reason for setting the ratio to 1.4 to 3.5 is that if the ratio is less than 1.4, welding failure of the welded portion occurs, and if it exceeds 3.5, burn-through occurs in the welded portion. In addition, the heat coefficient of the nominal thickness
The reason for setting the value to 4.5 is that if the value is less than 2.5, welding failure occurs at the welded portion, and if the value exceeds 4.5, burn-through occurs at the welded portion.
本発明の実施例について以下に説明する。突起付き電
縫鋼管の製造工程を、突起付き熱延コイルから不用な端
材を切断によって除去し、管素材を得る縁処理工程、管
素材を管に成形する成形工程および、溶接工程に分け、
以下に説明してゆく。Embodiments of the present invention will be described below. The manufacturing process of the ERW steel pipe with projections is divided into a rim treatment step of removing unnecessary scraps from the hot-rolled coils with projections to obtain a tube material, a forming process of forming the tube material into a tube, and a welding process.
This will be described below.
〈縁処理工程〉 通常、ロータリーシャーで熱延コイルの縁処理を行う
ときは、第５図に示すように、シェアダレが上向きにな
るようにローリーナイフ１で切断している。しかしなが
ら、管の内面側に突起を有する電縫管を製造する場合に
は、突起側７が上にくるため、切断を行うと切断線８の
ようになり、そのため第６図に示すように刃で突起を圧
延することになり、コイルエッジに波打ち９が発生す
る。波打ち９が発生すると、溶接品質が低下するばかり
でなく、溶接後の外観形状が悪くなるという難点があ
る。そこで、第７図に示すようにシェアダレが下向きに
なるようにローリーナイフ１の刃を組むことにより、コ
イルエッジの突起が圧延されることを防ぎ、コイルエッ
ジの波打ちの発生を防止する。ただし、管の外側面に突
起を有する電縫管を製造する場合は、第５図に示すよう
に通常の刃組で縁処理を行い、コイルエッジの波打ちの
発生を防止すればよい。図において２は熱延コイルであ
る。<Edge Processing Step> Normally, when performing the edge processing of the hot-rolled coil with a rotary shear, as shown in FIG. 5, the hot-rolled coil is cut with a lorry knife 1 so that the shear droop is directed upward. However, when manufacturing an electric resistance welded tube having a projection on the inner surface side of the tube, the projection side 7 comes up, so that when cutting is performed, the cutting line becomes like a cutting line 8, and as a result, as shown in FIG. As a result, the projections are rolled, and a wavy 9 is generated at the coil edge. When the undulations 9 occur, not only does the welding quality deteriorate, but also the appearance after welding deteriorates. Therefore, as shown in FIG. 7, by setting the blade of the lorry knife 1 so that the shear droop is directed downward, the protrusion of the coil edge is prevented from rolling, and the coil edge is prevented from waving. However, when manufacturing an electric resistance welded tube having a projection on the outer surface of the tube, as shown in FIG. 5, the edge treatment may be performed with a normal blade set to prevent the coil edge from waving. In the figure, reference numeral 2 denotes a hot-rolled coil.
エッジミーリングで縁処理を行えば、コイルエッジの
波打ちが発生しないので、エッジミーリングが使用可能
の場合は、エッジミーリングを使用した方がよい。ま
た、ロータリーシャーで刃組が不可能な場合は、シュア
ダレあるいは、波打ちの発生した縁をエッジミーリング
により除去すればよい。If edge processing is performed by edge milling, the coil edge does not undulate. Therefore, when edge milling can be used, it is better to use edge milling. In addition, when it is not possible to use a rotary shear to set the blade, it is only necessary to remove the edges where the undulations or undulations occur by edge milling.
〈成形工程〉 通常、コイルを成形する場合は、コイルエッジの成形
およびピンチ力を得るため、ブレークダウンスタンドの
トップロールおよび、ボトムロール間ギャップをコイル
の板厚に設定している。しかし、突起を有する熱延コイ
ルの場合には、突起部に圧延力が集中するため、突起は
極めて圧延され易い。そこで、突起が圧延されるのを防
止するため、ブレークダウンスタンドのトップロールと
ボトムロール間ギャップを “板厚＋突起高さ＋0.2〜1.0mm" に設定し、ピンチ力を得るぎりぎりの状態で熱延コイル
のトップをフィンパススタンドに噛み込むまで挿入し、
その後、ギャップを “板厚＋突起高さ＋1mm" 以上にすることにより突起の圧延を防止する。<Molding Step> Usually, when forming a coil, the gap between the top roll and the bottom roll of the breakdown stand is set to the thickness of the coil in order to form the coil edge and obtain a pinch force. However, in the case of a hot-rolled coil having projections, the rolling force concentrates on the projections, so that the projections are extremely easily rolled. Therefore, in order to prevent the projection from being rolled, the gap between the top roll and the bottom roll of the breakdown stand is set to “plate thickness + projection height + 0.2 to 1.0 mm”, and the pinch force is barely reached. Insert the top of the hot rolled coil until it bites into the fin pass stand,
Thereafter, the gap is set to be “plate thickness + projection height + 1 mm” or more to prevent the projection from rolling.
〈溶接工程〉 製造に供した熱延コイルの突起形状は、第１図に示す
ようなチェッカータイプと第２図（ａ）、（ｂ）、
（ｃ）に示すようなウエーブタイプの２種類を使用し
た。第１図において（ａ）図はチェッカータイプの突起
を有する鋼板の平面図である。（ｂ）図は（ａ）図のＡ
−Ａ線断面図である。ここにおいて３は突起、２は熱延
コイルを示している。第２図においては（ａ）図はウエ
ーブタイプの突起を有する鋼板の突起配置４を示してい
る。（ｂ）図はその要部拡大図である。（ｃ）は（ｂ）
図のＢ−Ｂ線断面図である。ここにおいて３は突起、２
は熱延コイルを示している。そして第１表に示す寸法の
熱延コイルを第２表に示す入熱条件で溶接を行った。溶
接に際しては、突起が付いているため、板厚違いの溶接
と等板厚の溶接が連続的に繰り返すことになるが、突起
付き部分でヒート係数が1.4〜3.5、呼称板厚部分でヒー
ト係数が2.5〜4.5になるように溶接入熱を制御すること
により、溶接部の溶着不良および、溶け落ちのない溶接
部が得られることが確認された。そして、第３図
（ａ）、（ｂ）は板厚と突起高さの比の最も大きな 14″×4.5（外径×肉厚） のパイプの溶接部断面を顕微鏡検査で５倍に拡大した場
合の模式図であり、（ａ）図は呼称板厚部の場合であ
り、（ｂ）図は突起付き部の場合を示す。その結果から
明らかなように、溶接ビードが厚さ全長にわたりきちん
と形成されていることが分かった。また、3tRのガイド
ベンドテストの結果、いずれのサイズでも割れの発生は
認められず、溶接品質に問題がないことが確認された。
板厚と突起高さの比の最も大きな 14″×4.5（外径×肉厚） のパイプについて、縁処理後の溶接部の凹凸の測定結果
を示したものが第３表で、扁平試験の結果を示したもの
が第４図である。各グラフの下部に記載した（ａ）〜
（ｄ）の符号は、第３表に示した縁処理の種類の符号の
（ａ）〜（ｄ）に対応するものである。これらの結果に
より、縁処理（ｂ），（ｃ），（ｄ）を施したものは、
扁平試験結果が全てJIS規格を満足していることが分か
る。<Welding process> The shape of the protrusion of the hot-rolled coil used in the production was a checker type as shown in FIG. 1 and FIGS. 2 (a) and 2 (b).
Two types of wave type as shown in (c) were used. FIG. 1A is a plan view of a steel plate having checker type projections. (B) The figure in (a) is A
FIG. 4 is a cross-sectional view taken along a line A. Here, 3 is a projection, and 2 is a hot-rolled coil. FIG. 2 (a) shows a projection arrangement 4 of a steel plate having wave type projections. (B) is an enlarged view of the main part. (C) is (b)
It is BB sectional drawing of a figure. Here, 3 is a protrusion, 2
Indicates a hot-rolled coil. Then, the hot rolled coils having the dimensions shown in Table 1 were welded under the heat input conditions shown in Table 2. At the time of welding, projections are attached, so welding of different thickness and welding of equal thickness will be repeated continuously, but the heat coefficient is 1.4 to 3.5 at the portion with projection and the heat coefficient at the nominal thickness portion It was confirmed that by controlling the welding heat input so as to be 2.5 to 4.5, it is possible to obtain a welded portion without poor welding and no burn-through. FIGS. 3 (a) and 3 (b) show the cross section of the welded portion of a 14 ″ × 4.5 (outer diameter × wall thickness) pipe having the largest ratio of the plate thickness to the projection height magnified 5 times by microscopic inspection. (A) shows the case of the nominal plate thickness part, and (b) shows the case of the projection part, as apparent from the result, the weld bead is properly formed over the entire thickness. In addition, as a result of the 3tR guide bend test, no cracking was observed at any size, and it was confirmed that there was no problem in welding quality.
Table 3 shows the measurement results of the unevenness of the welded portion after the edge treatment for a pipe of 14 "x 4.5 (outer diameter x wall thickness) with the largest ratio of the plate thickness to the projection height. The results are shown in Fig. 4. (a) to (a) are shown at the bottom of each graph.
The symbols (d) correspond to the symbols (a) to (d) of the types of edge processing shown in Table 3. According to these results, those subjected to edge processing (b), (c), and (d) are:
It can be seen that all the flat test results satisfy the JIS standard.
本発明の方法により製造した内面突起付き電縫管を母
管として、ロールフォーミングにより内面突起付き電縫
角形鋼管を製造し、その寸法測定結果を示したものが第
４表である。この表より角形鋼管としてJIS規格をほぼ
満足し、内面突起付き電縫角形鋼管が製造できることが
確認された。Table 4 shows the dimensions of the ERW square steel pipe with inner projections manufactured by roll forming using the ERW pipe with inner projections manufactured by the method of the present invention as a mother pipe. From this table, it was confirmed that the square steel pipe almost satisfied the JIS standard and that an electric resistance welded square steel pipe with inner projections could be manufactured.
［発明の効果］ 本発明は、両側縁に連続した平坦部を設けない突起付
き熱延コイルを使用し、外径200mmφ以上の電縫鋼管に
電縫溶接するにあたって、突起付き部分と呼称板部分に
ついて定めるヒート係数範囲に入るように溶接入熱を制
御して溶接を行うことにより、突起付き電縫鋼管を製造
するものであるから、平坦加工設備を必要とせず、溶接
品質の良好な溶接部を突起付き電縫鋼管を製造すること
ができる。従って、設備コストおよび、鋼管素材コスト
を安価にでき、また、生産性を低下しなくてすむという
効果が得られる。また、本発明の方法で製造された突起
付き電縫鋼管を母管として突起付き角形鋼管を製造でき
るというメリットが確認された。 [Effects of the Invention] The present invention uses a hot-rolled coil with projections that do not have continuous flat portions on both side edges and, when performing ERW welding on an ERW steel pipe having an outer diameter of 200 mmφ or more, a portion with a projection and a name plate portion. By controlling the welding heat input so as to fall within the heat coefficient range specified in the above, welding is performed to manufacture an ERW steel pipe with projections. An ERW steel pipe with projections can be manufactured. Therefore, it is possible to reduce the equipment cost and the cost of the steel tube material, and to obtain the effect that the productivity does not need to be reduced. Further, it was confirmed that a rectangular steel pipe with projections can be manufactured using the ERW steel pipe with projections manufactured by the method of the present invention as a mother pipe.
第１図は本発明の製造方法による突起付き電縫管の製造
に使用したチェッカータイプの突起を有する鋼板を示す
図、第２図は本発明の製造方法による突起付き電縫管の
製造に使用したウエーブタイプの突起に有する鋼板を示
す図、第３図は本発明の方法によって製造した突起付き
電縫管の溶接部断面を示す図、第４図は各種縁処理方法
と溶接方法の組合せにより製造した突起付き電縫管の扁
平試験結果を示すグラフ、第５図はロータリーシャーに
よる通常の切断を示す図、第６図は通常の切断によって
突起部が圧延されて波打ちが発生した状況を示す図、第
７図はロータリーシャーの刃の配置替えにより波打ちを
防止する切断を示す図である。 ２……熱延コイル、３……突起、４……突起配置、５…
…溶接ビード、６……溶接ボンド、７……突起側、８…
…切断線、９……切断後の波打ち。FIG. 1 is a view showing a steel plate having checker type projections used for manufacturing an ERW pipe with projections according to the manufacturing method of the present invention, and FIG. 2 is used for manufacturing an ERW pipe with projections according to the manufacturing method of the present invention. FIG. 3 is a view showing a welded section of an ERW pipe with protrusions manufactured by the method of the present invention, and FIG. 4 is a view showing combinations of various edge treatment methods and welding methods. FIG. 5 is a graph showing a result of a flat test of the manufactured electric resistance welded tube with protrusions, FIG. 5 is a diagram showing normal cutting by a rotary shear, and FIG. FIG. 7 is a diagram showing cutting for preventing waving by rearranging the blades of the rotary shear. 2 ... hot-rolled coil, 3 ... protrusion, 4 ... protrusion arrangement, 5 ...
... weld bead, 6 ... weld bond, 7 ... projection side, 8 ...
... cut line, 9 ... wavy after cutting.
フロントページの続き (72)発明者 小島 眞二 東京都千代田区丸の内１丁目１番２号 日本鋼管株式会社内 (72)発明者 松村 弘道 東京都千代田区丸の内１丁目１番２号 日本鋼管株式会社内 審査官 坂本 薫昭 (56)参考文献 特開 昭55−27437（ＪＰ，Ａ) 特開 昭60−56418（ＪＰ，Ａ) 特公 昭61−57087（ＪＰ，Ｂ２)Continuing from the front page (72) Inventor Shinji Kojima 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. (72) Inventor Hiromichi Matsumura 1-1-2 Marunouchi, Chiyoda-ku, Tokyo Nippon Kokan Co., Ltd. Examiner Kaoru Sakamoto (56) References JP-A-55-27437 (JP, A) JP-A-60-56418 (JP, A) JP-B-61-57087 (JP, B2)
Claims (1)
延コイルを使用し、外径200mmφ以上の電縫管に電縫溶
接するにあたって、突起付き部分にヒート係数が1.4〜
3.5に、かつ呼称板厚部分のヒート係数が2.5〜4.5の範
囲に入るように溶接入熱を制御して溶接することを特徴
とする突起付き電縫鋼管の製造方法である。但し、ヒー
ト係数＝（溶接投入電力）／（溶接速度×板厚）［（KV
・Ａ・min/m2）×103］The present invention relates to a hot-rolled coil having projections without a flat portion on both side edges, and when performing ERW welding on an ERW pipe having an outer diameter of 200 mmφ or more, a heat coefficient of the projection portion is 1.4 to less.
A method for producing an electric resistance welded steel pipe with projections, characterized in that welding is performed by controlling welding heat input so that the heat coefficient of a nominal plate thickness portion falls within a range of 2.5 to 4.5. However, heat coefficient = (welding input power) / (welding speed x plate thickness) [(KV
・ A ・ min / m 2 ) × 10 3 ]
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63105058A JP2636322B2 (en) | 1988-04-27 | 1988-04-27 | Manufacturing method of ERW steel pipe with projection |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63105058A JP2636322B2 (en) | 1988-04-27 | 1988-04-27 | Manufacturing method of ERW steel pipe with projection |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01273680A JPH01273680A (en) | 1989-11-01 |
| JP2636322B2 true JP2636322B2 (en) | 1997-07-30 |
Family
ID=14397376
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63105058A Expired - Fee Related JP2636322B2 (en) | 1988-04-27 | 1988-04-27 | Manufacturing method of ERW steel pipe with projection |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2636322B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US8540136B1 (en) * | 2012-09-06 | 2013-09-24 | Taiwan Semiconductor Manufacturing Company, Ltd. | Methods for stud bump formation and apparatus for performing the same |
| CN116038173A (en) * | 2023-01-07 | 2023-05-02 | 中铁宝桥集团有限公司 | Submerged arc welding wire and flux combined deposited metal mechanical property test plate welding method |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5527437A (en) * | 1978-08-15 | 1980-02-27 | Kawasaki Steel Corp | Production of small diameter electric welded steel tube |
| JPS6056418A (en) * | 1983-09-07 | 1985-04-02 | Sanou Kogyo Kk | Manufacture of grooved pipe |
| JPS6157087A (en) * | 1984-05-30 | 1986-03-22 | Mitsubishi Electric Corp | Floating head slider |
-
1988
- 1988-04-27 JP JP63105058A patent/JP2636322B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01273680A (en) | 1989-11-01 |
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