JPH08294722A - Production of large sized square steel tube and large sized round steel tube - Google Patents
Production of large sized square steel tube and large sized round steel tubeInfo
- Publication number
- JPH08294722A JPH08294722A JP7099051A JP9905195A JPH08294722A JP H08294722 A JPH08294722 A JP H08294722A JP 7099051 A JP7099051 A JP 7099051A JP 9905195 A JP9905195 A JP 9905195A JP H08294722 A JPH08294722 A JP H08294722A
- Authority
- JP
- Japan
- Prior art keywords
- steel pipe
- steel tube
- large sized
- round steel
- pipe
- 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.)
- Granted
Links
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、たとえば建築用の柱材
に使用される正方体形状や直方体形状の大形角形鋼管の
製造方法、ならびに大形丸形鋼管の製造方法に関するも
のである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a large rectangular steel tube having a rectangular shape or a rectangular parallelepiped shape used for, for example, a pillar material for construction, and a method for manufacturing a large round steel tube.
【０００２】[0002]
【従来の技術】従来、建築用の柱材などに使用される大
形角形鋼管は、たとえば特公昭58−13245 号公報に見ら
れる製造方法で得られていた。すなわち、この従来方法
は、一枚の厚肉鋼鈑を長さ方向に移送して両側の開先加
工を行ったのち、プレスにて、角形鋼管の四隅に相当す
る部分曲げ加工して角形鋼管近似の形状に成形し、次い
で近似角形鋼管を複数段の成形ロールに通して角形鋼管
形状に成形しつつ、開先突き合わせ面を順次仮付け溶接
し、次に開先部材内外面を自動溶接によって溶接したの
ち、歪み取りを行うことで、大形角形鋼管を得ていた。2. Description of the Related Art Conventionally, large rectangular steel pipes used for building pillars and the like have been obtained by the manufacturing method disclosed in, for example, Japanese Patent Publication No. 58-13245. That is, in this conventional method, one thick steel plate is transferred in the length direction to perform groove forming on both sides, and then a press is used to partially bend the square steel pipe to form the square steel pipe. While forming into an approximate shape, then passing the approximate square steel pipe through multiple stages of forming rolls into a rectangular steel pipe shape, the groove abutting surfaces are sequentially tack welded, and then the internal and external surfaces of the groove member are automatically welded. After welding, strain relief was performed to obtain a large rectangular steel pipe.
【０００３】[0003]
【発明が解決しようとする課題】上記した冷間成形によ
り製造された大形角形鋼管によると、たとえば図５の内
面側硬さ分布グラフ図や、図６の外面側硬さ分布グラフ
図から分かるように、角部およびシーム溶接部の硬さが
平板部（母材）に比べてかなり高い値となる。このた
め、角部およびシーム溶接部の降伏強さが増大し、延性
の低下をきたすことになり、以て二次溶接などを施工す
る際に割れを引き起こす恐れがあることから、特別な管
理を必要とし、また機械的性質が不均一で残留応力が発
生していることから、切削加工などを容易に行えない。According to the large rectangular steel pipe manufactured by the cold forming described above, it can be understood from the graph of hardness distribution on the inner surface side in FIG. 5 and the graph of hardness distribution on the outer surface side in FIG. 6, for example. As described above, the hardness of the corner portion and the seam welded portion is considerably higher than that of the flat plate portion (base material). For this reason, the yield strength of the corners and seam welds increases, leading to a decrease in ductility, which may cause cracks when performing secondary welding, so special control is required. Since it is necessary, and the mechanical properties are non-uniform and residual stress is generated, it is not possible to easily perform cutting work.
【０００４】また従来の大形角形鋼管によると、たとえ
ば図７の引張応力−伸び曲線比較図から分かるように、
角部、シーム溶接部および平板部の全てに降伏点が表れ
ないことから、局部的な応力分布がしばしば生じる構造
物の場合には、最大降伏比が80％を越えると、構造物と
しての局部的な伸び能力が低下し、破壊に至る危険性が
高くなる恐れがあり、特に耐震性が望まれる建築用に不
十分となる。Further, according to the conventional large rectangular steel pipe, for example, as can be seen from the tensile stress-elongation curve comparison diagram of FIG.
Since the yield point does not appear on all corners, seam welds and flat plates, in the case of a structure where local stress distribution often occurs, if the maximum yield ratio exceeds 80%, the local structure There is a risk that the effective elongation capacity will decrease and the risk of destruction will increase, and it will be insufficient especially for buildings where earthquake resistance is desired.
【０００５】さらに従来の大形角形鋼管によると、特に
角部やシーム溶接部には降伏点に近い引張および圧縮残
留応力が発生しており、座屈強度は低いものになる。し
たがって、溶接施工、切断加工あるいは溶融亜鉛メッキ
処理などを実施する際に、これら残留応力の開放に伴っ
て生じる割れやコントロールできないような変形を引き
起こす恐れがある。Further, according to the conventional large rectangular steel pipe, tensile and compressive residual stresses near the yield point are generated particularly at the corners and seam welds, and the buckling strength becomes low. Therefore, when performing welding, cutting, hot dip galvanizing, or the like, there is a risk of causing cracks or uncontrollable deformation that accompany the release of these residual stresses.
【０００６】そして従来の大形角形鋼管によると、たと
えば図８の遷移曲線図から分かるように、特に角部は、
曲げ加工によって局部的に大きな靱性ひずみが残留する
ため、この箇所が著しく脆化し、遷移温度が常温をはる
かに越えることがあり、低温域において破壊に至る恐れ
がある。According to the conventional large-sized rectangular steel pipe, for example, as can be seen from the transition curve diagram of FIG.
Since a large toughness strain locally remains due to bending, this portion may be significantly embrittled, the transition temperature may far exceed normal temperature, and there is a risk of fracture in the low temperature region.
【０００７】本発明の目的とするところは、全断面が均
質で軟らかく、伸びがよく、しかも残留応力が殆どな
く、かつ十分な靱性を有する大形角形鋼管の製造方法、
ならびに大形丸形鋼管の製造方法を提供する点にある。An object of the present invention is to provide a method for manufacturing a large rectangular steel pipe having a uniform cross section, softness, good elongation, little residual stress, and sufficient toughness.
Another object is to provide a method for manufacturing a large round steel pipe.
【０００８】[0008]
【課題を解決するための手段】上記目的を達成すべく本
第１発明の大形角形鋼管の製造方法は、大形角形鋼管に
見合う所定の径、板厚、長さの丸形鋼管を原管として、
この原管を加熱炉で加熱し、次いで加熱した原管を丸形
鋼管成形ミルで熱間成形して精製原管とし、そして精製
原管を角形鋼管成形ミルで熱間成形して大形角形鋼管と
し、この大形角形鋼管を冷却床で冷却したのち、切断装
置により端部の成形不良部分を切断除去している。In order to achieve the above object, a method for manufacturing a large rectangular steel pipe according to the first aspect of the present invention is based on a round steel pipe having a predetermined diameter, plate thickness and length commensurate with the large rectangular steel pipe. As a tube
This raw pipe is heated in a heating furnace, and then the heated raw pipe is hot-formed in a round steel pipe forming mill to make a refined raw pipe, and the refined raw pipe is hot-formed in a square steel pipe forming mill to make a large rectangular pipe. A steel pipe is used, and this large rectangular steel pipe is cooled in a cooling bed, and then a cutting device is used to cut and remove the defective molding portion at the end.
【０００９】また本第２発明の大形丸形鋼管の製造方法
は、大形丸形鋼管に見合う所定の径、板厚、長さの丸形
鋼管を原管として、この原管を加熱炉で加熱し、次いで
加熱した原管を丸形鋼管成形ミルで熱間成形して大形丸
形鋼管とし、そして大形丸形鋼管を冷却床で冷却したの
ち、切断装置により端部の成形不良部分を切断除去して
いる。Further, the method for manufacturing a large round steel pipe according to the second aspect of the present invention uses a round steel pipe having a predetermined diameter, thickness and length commensurate with the large round steel pipe as a raw pipe, and the raw pipe is a heating furnace. After that, the heated raw pipe is hot-formed in a round steel pipe forming mill to form a large round steel pipe, and the large round steel pipe is cooled in a cooling bed, and then the end device is defectively formed by a cutting device. The part is cut off.
【００１０】[0010]
【作用】上記した本第１発明の構成によると、加熱炉で
加熱した原管を、丸形鋼管成形ミルで熱間成形して、最
終の大形角形鋼管が所定の寸法で仕上がる直径の精製原
管とし、そして精製原管を角形鋼管成形ミルで熱間成形
して、平板部が膨らみ状の大形角形鋼管とし、この大形
角形鋼管を冷却床で冷却して平板部を直状に収縮させた
のち、切断装置により端部の成形不良部分を切断除去す
ることで、所定の板厚、長さの大形角形鋼管を得てい
る。According to the first aspect of the present invention described above, the raw pipe heated in the heating furnace is hot-formed by the round-steel pipe forming mill, and the final large rectangular steel pipe is refined to have a predetermined diameter. The raw raw pipe is hot-formed in a square steel pipe forming mill to produce a large square steel pipe with a bulging flat plate portion.The large square steel pipe is cooled in a cooling bed to straighten the flat plate portion. After shrinking, a defective cutting portion at the end is cut and removed by a cutting device to obtain a large rectangular steel pipe having a predetermined plate thickness and length.
【００１１】また本第２発明の構成によると、加熱炉で
加熱した原管を、丸形鋼管成形ミルで熱間成形して大形
丸形鋼管とし、そして冷却床で冷却したのち、切断装置
により端部の成形不良部分を切断除去することで、所定
の径、板厚、長さの大形丸形鋼管を得ている。According to the structure of the second aspect of the present invention, the raw pipe heated in the heating furnace is hot-formed into a large round steel pipe by a round steel pipe forming mill and cooled in a cooling bed, and then the cutting device is used. By cutting and removing the defective molding portion at the end, a large round steel pipe having a predetermined diameter, plate thickness and length is obtained.
【００１２】[0012]
【実施例】以下に本発明の一実施例を図１〜図４に基づ
いて説明する。図１に示すように、大形角形鋼管を製造
するに当たり、この大形角形鋼管に見合う所定の径、板
厚、長さの丸形鋼管が、原管（母管）１として搬入床10
上に準備される。ここで原管１は、高周波溶接やアーク
溶接などによるシーム溶接部２を有する状態で製造され
ているが、これはシームレスの原管１であってもよい。
搬入床10はローラコンベヤ形式であって、複数本の原管
１を平行させて支持し、そして長さ方向に対して横方向
へと搬送させる。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. As shown in FIG. 1, in manufacturing a large rectangular steel pipe, a round steel pipe having a predetermined diameter, plate thickness and length commensurate with this large rectangular steel pipe is transferred as a raw pipe (mother pipe) 1 to the loading floor 10
Prepared on. Here, the raw pipe 1 is manufactured in a state having the seam welded portion 2 by high-frequency welding, arc welding or the like, but this may be a seamless raw pipe 1.
The loading floor 10 is of a roller conveyor type and supports a plurality of raw tubes 1 in parallel and transports them in a direction transverse to the length direction.
【００１３】搬入床10の終端部に搬送された原管１は、
ローラコンベヤ形式の加熱部コンベヤ11に受け取られ、
そして長さ方向に搬送される。次いで原管１は、加熱炉
12内に搬入され、この加熱炉12内での搬送中に800 ℃〜
950 ℃（Ａ3 変態点以上）で高温加熱される。加熱炉12
に対しては、原管１が順次搬入されるのであり、その際
に原管１の端面間に間隔Ｌを置くことで、加熱時の原管
１の伸びや搬送速度差によって端面どうしが接触（衝
突）などすることを防止し得る。なお間隔Ｌが長過ぎた
ときには効率が悪いものとなり、したがって間隔Ｌは50
0mm 以下に制御される。The raw tube 1 transferred to the end of the loading floor 10 is
Received by the roller conveyor type heating section conveyor 11,
Then, it is conveyed in the length direction. Next, the raw tube 1 is a heating furnace.
It is loaded into the heating furnace 12 and the temperature of 800 ℃
Is high temperature heating at 950 ° C. (A 3 transformation point or higher). Heating furnace 12
On the other hand, since the raw pipe 1 is sequentially loaded, by placing a space L between the end faces of the raw pipe 1 at that time, the end faces come into contact with each other due to the elongation of the raw pipe 1 at the time of heating and the difference in transport speed. (Collision) or the like can be prevented. If the interval L is too long, the efficiency is poor, so the interval L is 50
It is controlled to 0 mm or less.
【００１４】所定の温度に加熱された原管１は、加熱炉
12内から搬出され、そして溶接シーム位置調整装置15へ
搬入される。この溶接シーム位置調整装置15は、支持ロ
ール16や押えロール17などにより構成され、これらロー
ル16，17を介して原管１を管軸心の回りに回転させて、
シーム溶接部２の位置を一定の方向に揃える。この一定
の方向とは、最終の大形角形鋼管を得たとき、シーム溶
接部２を常に平板部の中央付近に存在させる位置とな
る。なお、シームレスの原管１が搬送されてきたとき、
この溶接シーム位置調整装置15の部分はパスされ、また
シームレスの原管１のみを使用する場合、溶接シーム位
置調整装置15による工程は削除される。The raw tube 1 heated to a predetermined temperature is a heating furnace.
It is carried out from inside 12 and then carried into the welding seam position adjusting device 15. The welding seam position adjusting device 15 is composed of a support roll 16, a press roll 17, etc., and rotates the raw pipe 1 around the pipe axis via these rolls 16 and 17,
The position of the seam weld 2 is aligned in a fixed direction. This fixed direction is a position in which the seam welded portion 2 is always present near the center of the flat plate portion when the final large rectangular steel pipe is obtained. In addition, when the seamless raw tube 1 is transported,
This part of the welding seam position adjusting device 15 is passed, and when only the seamless raw pipe 1 is used, the process by the welding seam position adjusting device 15 is deleted.
【００１５】溶接シーム位置調整装置15からの原管１
は、丸形鋼管成形ミル20に搬入される。ここでは、複数
のサイジングロール21などを介して原管１を絞り状に熱
間成形させるもので、最終の大形角形鋼管（製品）が所
定の寸法で仕上がるように、原管１を所定の直径に精製
する。ここで丸形鋼管成形ミル20は前後で二段に配設さ
れているが、これは一段または二段以上であってもよ
い。Raw pipe 1 from welding seam position adjusting device 15
Is carried into the round steel pipe forming mill 20. Here, the raw pipe 1 is hot-formed into a narrow shape through a plurality of sizing rolls 21 and the like, and the raw pipe 1 is set to a predetermined size so that the final large rectangular steel pipe (product) is finished to a predetermined size. Purify to diameter. Here, the round steel pipe forming mill 20 is arranged in two stages at the front and rear, but this may be one stage or two or more stages.
【００１６】丸形鋼管成形ミル20の周辺で、必要する箇
所（丸形鋼管成形ミル20の前後、前のみ、後ろのみ、ス
タンド間など）には、必要とする数のデスケーラー装置
23が設けられている。このデスケーラー装置23は、精製
原管１Ａに対して水圧をかけた水を噴射するもので、こ
の水噴射によりミルスケールなどを除去し、表面肌を良
くし得る。Around the round steel pipe forming mill 20, where necessary (front and rear of the round steel pipe forming mill 20, only front, only behind, between stands, etc.), a required number of descaler devices are provided.
23 are provided. The descaler device 23 injects water under water pressure to the refined raw pipe 1A, and can remove mill scale and the like by this water injection to improve the surface texture.
【００１７】このようにして丸形鋼管成形ミル20群によ
り精製された精製原管１Ａは、角形鋼管成形ミル25に搬
入される。ここでは、複数のつづみ形ロール26などを介
して最終の熱間成形（成形温度Ａ3 変態点以上）を行う
もので、その際に熱間成形直後の大形角形鋼管３は、図
４のＡに示すように、各平板部３ａがつづみ面に沿った
外方への円弧面に成形されている。なお角形鋼管成形ミ
ル25は前後で二段に配設されているが、これは一段また
は二段以上であってもよい。The refined raw pipe 1A thus purified by the round steel pipe forming mill 20 group is carried into the square steel pipe forming mill 25. Here, the final hot forming (forming temperature A 3 transformation point or higher) is performed through a plurality of stencil-shaped rolls 26, and at that time, the large rectangular steel pipe 3 immediately after hot forming is As shown in A, each flat plate portion 3a is formed in an outward arc surface along the joining surface. The square steel pipe forming mill 25 is arranged in two stages at the front and rear, but this may be one stage or two or more stages.
【００１８】このようにして熱間成形された大形角形鋼
管３は、加熱部コンベヤ11から冷却床28に受け取られ
る。この冷却床28はローラコンベヤ形式であって、複数
本の大形角形鋼管３を平行させて支持し、そして長さ方
向に対して横方向へと搬送させる。この冷却床28での搬
送中に、大形角形鋼管３は空冷形式で除冷される。この
除冷により大形角形鋼管３は、各平板部３ａが収縮さ
れ、以て図４のＢに示すように円弧面が直状面となり、
また角部３ｂのＲはシャープとなって、断面係数が高く
なる。The large rectangular steel tube 3 thus hot-formed is received from the heating section conveyor 11 on the cooling floor 28. The cooling floor 28 is of a roller conveyor type and supports a plurality of large rectangular steel pipes 3 in parallel with each other and conveys them in a direction transverse to the length direction. During the transportation on the cooling floor 28, the large rectangular steel tube 3 is cooled by air cooling. By this cooling, each flat plate portion 3a of the large rectangular steel pipe 3 is contracted, so that the arcuate surface becomes a straight surface as shown in FIG. 4B.
Further, the R of the corner portion 3b becomes sharp and the section modulus becomes high.
【００１９】冷却床28での大形角形鋼管３群の搬送は、
隣接した大形角形鋼管３の間を離した状態で、または隣
接した大形角形鋼管３どうしを接触させ両側よりクラン
プした状態で搬送される。これにより大形角形鋼管３
は、同じ雰囲気温度下で除冷されることになり、以て冷
却時の曲がりを少なくし得る。The transportation of the large rectangular steel tube group 3 in the cooling floor 28
The large square steel tubes 3 adjacent to each other are conveyed apart from each other, or the large square steel tubes 3 adjacent to each other are brought into contact with each other and clamped from both sides. As a result, large rectangular steel pipe 3
Will be cooled under the same ambient temperature, so that bending during cooling can be reduced.
【００２０】冷却床28の終端に達した大形角形鋼管３
は、ローラコンベヤ形式の第１搬送コンベヤ29に受け取
られ、そして長さ方向に搬送される。次いで大形角形鋼
管３は図２に示すように矯正装置30に搬入され、ここ
で、冷却時に発生した長手方向の大曲り、すなわち基準
値以上にある曲がりが矯正される。なお曲がりが基準値
以下である大形角形鋼管３は、矯正装置30による矯正を
パスしてもよいし、すべてを矯正装置30により矯正して
もよい。Large rectangular steel pipe 3 reaching the end of the cooling floor 28
Is received by a first conveyor 29 of the roller conveyor type and conveyed longitudinally. Next, the large rectangular steel pipe 3 is carried into the straightening device 30 as shown in FIG. 2, where the large bending in the longitudinal direction generated during cooling, that is, the bending that is equal to or larger than the reference value is corrected. The large rectangular steel pipe 3 whose bend is equal to or less than the reference value may pass the straightening by the straightening device 30, or may be entirely straightened by the straightening device 30.
【００２１】矯正装置30を通った大形角形鋼管３は、第
１搬送コンベヤ29からローラコンベヤ形式の中継床32に
移され、そして長さ方向に対して横方向へと搬送され
る。この中継床32の終端に達した大形角形鋼管３は、ロ
ーラコンベヤ形式の第２搬送コンベヤ33に受け取られ、
そして長さ方向に搬送される。この搬送中において大形
角形鋼管３は、まず先端切断装置35によって、成形時に
生じた先端（一端）の成形不良部分が切断除去され、次
いで後端切断装置36によって後端（他端）の成形不良部
分が切断除去され、以て所定寸法でかつ全長に亘って精
度のよい大形角形鋼管（製品）３にし得る。The large rectangular steel pipe 3 having passed through the straightening device 30 is transferred from the first transfer conveyor 29 to the relay floor 32 of the roller conveyor type, and is transferred laterally with respect to the length direction. The large rectangular steel pipe 3 reaching the end of the relay floor 32 is received by the second conveyor conveyor 33 of the roller conveyor type,
Then, it is conveyed in the length direction. During this conveyance, the large square steel pipe 3 is first cut by the tip cutting device 35 to remove the defective molding portion of the tip (one end) generated during molding, and then the rear end cutting device 36 forms the rear end (other end). The defective portion is cut and removed, whereby a large rectangular steel pipe (product) 3 having a predetermined size and high accuracy over the entire length can be obtained.
【００２２】このように成形された大形角形鋼管３は、
図３に示すように、第２搬送コンベヤ33からローラコン
ベヤ形式の洗浄床38に移され、そして長さ方向に対して
横方向へと搬送される。この搬送中において大形角形鋼
管３は、洗浄装置40における外面洗浄ノズル41や内面洗
浄ノズル42から噴射される洗浄水により、各工程（加
熱、成形、冷却、矯正、切断など）においてその内外面
に付着しているスケール、ゴミ、切り粉などが洗浄除去
される。The large rectangular steel pipe 3 thus formed is
As shown in FIG. 3, it is transferred from the second transfer conveyor 33 to a cleaning floor 38 of the roller conveyor type and is transferred laterally to the lengthwise direction. During this transportation, the large rectangular steel pipe 3 is subjected to cleaning water sprayed from the outer surface cleaning nozzle 41 and the inner surface cleaning nozzle 42 in the cleaning device 40, and the inner and outer surfaces thereof in each step (heating, molding, cooling, straightening, cutting, etc.). The scale, dust, cutting chips, etc. adhering to the are cleaned and removed.
【００２３】そして大形角形鋼管３は、洗浄床38からロ
ーラコンベヤ形式の第３搬送コンベヤ44に移され、長さ
方向に搬送される。この搬送中において大形角形鋼管３
は、防錆装置45を通り、以て保管中または使用中に錆が
でないように防錆処理される。その後に大形角形鋼管３
は、第３搬送コンベヤ44からローラコンベヤ形式の搬出
床46に移され、そして長さ方向に対して横方向へと搬送
されるとともに、密状でストレージされる。Then, the large rectangular steel pipe 3 is transferred from the cleaning floor 38 to the third conveyor conveyor 44 of the roller conveyor type and conveyed in the length direction. Large square steel pipe 3 during this transportation
Passes through the anticorrosion device 45, and is thus subjected to anticorrosion treatment to prevent rust during storage or use. After that, large rectangular steel pipe 3
Are transferred from the third transfer conveyor 44 to a roller conveyor type unloading floor 46, transferred laterally with respect to the lengthwise direction, and stored in a dense manner.
【００２４】以上のようにして、丸管から角管への成形
を熱間成形することで製造した大形角形鋼管３は、たと
えば図５の内面側硬さ分布グラフ図や、図６の外面側硬
さ分布グラフ図から分かるように、平板部３ａ、角部３
ｂおよびシーム溶接部２など全断面に亘って機械的性質
がほぼ均質となる。このため、角部３ｂおよびシーム溶
接部２の降伏強さは低下し、延性を増大させることにな
り、以て二次溶接などは特別な管理を必要とすることな
く施工し得、また機械的性質が均一であることから、切
削加工などを容易に行える。As described above, the large rectangular steel tube 3 manufactured by hot forming the round tube into the rectangular tube has, for example, the hardness distribution graph of the inner surface of FIG. 5 and the outer surface of FIG. As can be seen from the side hardness distribution graph, the flat plate portion 3a, the corner portion 3
The mechanical properties are substantially uniform over the entire cross section such as b and the seam welded portion 2. Therefore, the yield strength of the corner portion 3b and the seam welded portion 2 is reduced, and the ductility is increased, so that secondary welding can be performed without requiring special management, and mechanical strength is also increased. Since the properties are uniform, it is possible to easily perform cutting work.
【００２５】また熱間成形した大形角形鋼管３による
と、たとえば図７の引張応力−伸び曲線比較図から分か
るように、平板部３ａ、角部３ｂおよびシーム溶接部２
の全てに降伏点が現れ、降伏比は規格値80％をはるかに
下回り、安定しており、十分な伸び能力を有している。
したがって、局部的な応力分布がしばしば生じるところ
の、たとえば建築用の柱材として採用したとき、ぜい性
破壊に至る危険性が低くなり、特に耐震性が望まれる建
築用の柱材として理想的な材料特性となる。Further, according to the large-sized rectangular steel tube 3 formed by hot forming, as can be seen from the tensile stress-elongation curve comparison diagram of FIG. 7, for example, the flat plate portion 3a, the corner portion 3b and the seam welded portion 2 are formed.
Yield point appeared in all of, the yield ratio was far below the standard value of 80%, stable, and had sufficient elongation ability.
Therefore, when it is used as a column material for construction where local stress distribution often occurs, for example, the risk of brittle fracture is reduced, and it is ideal as a column material for construction especially where earthquake resistance is desired. Material characteristics.
【００２６】さらに熱間成形した大形角形鋼管３による
と、平板部３ａ、角部３ｂ、シーム溶接部２など、全て
に亘って引張および圧縮残留応力が殆どなく、以て高い
座屈強度が得られる。したがって、溶接施工、切断加工
あるいは溶融亜鉛メッキ処理などを実施する際に、割れ
やコントロールできないような変形は発生しない。Further, according to the large-sized rectangular steel pipe 3 formed by hot forming, there is almost no tensile and compressive residual stress over the flat plate portion 3a, the corner portion 3b, the seam welded portion 2, and the like, so that a high buckling strength is obtained. can get. Therefore, cracking or uncontrollable deformation does not occur during welding, cutting, hot dip galvanizing, or the like.
【００２７】そして熱間成形した大形角形鋼管３による
と、たとえば図８の遷移曲線図から分かるように、平板
部３ａ、角部３ｂ、シーム溶接部２の全てに亘って原板
と同じような遷移曲線を示し、低温域でも十分な靱性を
有することになる。According to the large-sized rectangular steel tube 3 hot-formed, for example, as can be seen from the transition curve diagram of FIG. 8, the flat plate portion 3a, the corner portion 3b, and the seam welded portion 2 are all the same as the original plate. It shows a transition curve and has sufficient toughness even at low temperatures.
【００２８】図９は本発明の別の実施例を示す。すなわ
ち前実施例の異なるところは、丸形鋼管成形ミル20で熱
間成形した精製原管を大形丸形鋼管５として冷却床28に
取出している。そして冷却床28にて除冷したのち、前実
施例と同様に、矯正装置30、中継床32、切断装置35，3
6、洗浄床38、洗浄装置40、防錆装置45へと搬送され、
搬出床46にストレージされるものである。FIG. 9 shows another embodiment of the present invention. That is, what is different from the previous embodiment is that the refined raw pipe hot-formed by the round steel pipe forming mill 20 is taken out to the cooling bed 28 as the large round steel pipe 5. Then, after cooling in the cooling floor 28, as in the previous embodiment, the straightening device 30, the relay floor 32, the cutting devices 35, 3 are used.
6, transferred to the cleaning floor 38, cleaning device 40, rust prevention device 45,
It is stored in the unloading floor 46.
【００２９】このようにして熱間成形した大形丸形鋼管
５は寝前述した大形角形鋼管３と同様な性状を有するも
のである。The large round steel pipe 5 hot-formed in this manner has the same properties as the large square steel pipe 3 described above.
【００３０】[0030]
【発明の効果】上記構成の本第１発明によると、熱間成
形により、全断面が均質で軟らかく、伸びがよく、しか
も残留応力が殆どなくて高い座屈強度を得られるととも
に、二次溶接性に優れ、かつ十分な靱性を有する大形角
形鋼管を製造でき、特に建築用の柱材として好適な大形
角形鋼管を提供できる。According to the first aspect of the present invention having the above-mentioned structure, by hot forming, the entire cross section is uniform and soft, the elongation is good, and there is almost no residual stress, and high buckling strength can be obtained. It is possible to manufacture a large rectangular steel pipe having excellent toughness and sufficient toughness, and in particular, it is possible to provide a large rectangular steel pipe suitable as a column material for construction.
【００３１】また上記構成の本第２発明によると、同様
な性状の大形丸形鋼管を提供できる。Further, according to the second invention of the above construction, a large round steel pipe having similar properties can be provided.
【図１】本発明の一実施例を示し、大形角形鋼管の製造
方法における熱間成形までの工程斜視図である。FIG. 1 is a perspective view of a process up to hot forming in a method for manufacturing a large rectangular steel pipe according to an embodiment of the present invention.
【図２】同大形角形鋼管の製造方法における後処理部分
の工程斜視図である。FIG. 2 is a process perspective view of a post-treatment portion in the method for manufacturing the large-sized rectangular steel pipe.
【図３】同大形角形鋼管の製造方法における洗浄部分の
工程斜視図である。FIG. 3 is a process perspective view of a cleaning portion in the manufacturing method of the large rectangular steel pipe.
【図４】同大形角形鋼管の製造方法で製造された大形角
形鋼管を示し、Ａは成形直後、Ｂは冷却後の正面図であ
る。FIG. 4 is a front view showing a large-sized rectangular steel pipe manufactured by the same manufacturing method for a large-sized rectangular steel pipe, where A is immediately after forming and B is after cooling.
【図５】同従来品と比較した内面側の硬さ分布グラフ図
である。FIG. 5 is a graph showing hardness distribution on the inner surface side as compared with the conventional product.
【図６】同従来品と比較した外面側の硬さ分布グラフ図
である。FIG. 6 is a hardness distribution graph diagram on the outer surface side compared with the conventional product.
【図７】同従来品と比較した引張応力−伸び曲線比較図
である。FIG. 7 is a tensile stress-elongation curve comparison diagram in comparison with the conventional product.
【図８】同従来品と比較した遷移曲線図である。FIG. 8 is a transition curve diagram in comparison with the conventional product.
【図９】本発明の別の実施例を示し、大形丸形鋼管の製
造方法における熱間成形までの工程斜視図である。FIG. 9 is a perspective view showing a process up to hot forming in a method for manufacturing a large round steel pipe according to another embodiment of the present invention.
１ 原管（丸形鋼管） １Ａ 精製原管 ２ シーム溶接部 ３ 大形角形鋼管 ３ａ 平板部 ３ｂ 角部 ５ 大形丸形鋼管 12 加熱炉 15 溶接シーム位置調整装置 20 丸形鋼管成形ミル 23 デスケーラー装置 25 角形鋼管成形ミル 26 つづみロール 28 冷却床 30 矯正装置 35 先端切断装置 36 後端切断装置 38 洗浄床 40 洗浄装置 45 防錆装置 46 搬出床 1 Raw Pipe (Round Steel Pipe) 1A Purified Raw Pipe 2 Seam Welding Part 3 Large Square Steel Pipe 3a Flat Plate Part 3b Corner 5 Large Round Steel Pipe 12 Heating Furnace 15 Welding Seam Positioning Device 20 Round Steel Pipe Forming Mill 23 Descaler Device 25 Square steel pipe forming mill 26 Catch roll 28 Cooling floor 30 Straightening device 35 Straightening device 35 Rear cutting device 38 Washing floor 40 Cleaning device 45 Rust preventive device 46 Outgoing floor
─────────────────────────────────────────────────────
─────────────────────────────────────────────────── ───
【手続補正書】[Procedure amendment]
【提出日】平成７年７月３１日[Submission date] July 31, 1995
【手続補正１】[Procedure Amendment 1]
【補正対象書類名】明細書[Document name to be amended] Statement
【補正対象項目名】００１３[Correction target item name] 0013
【補正方法】変更[Correction method] Change
【補正内容】[Correction content]
【００１３】搬入床10の終端部に搬送された原管１は、
ローラコンベヤ形式の加熱部コンベヤ11に受け取られ、
そして長さ方向に搬送される。次いで原管１は、加熱炉
12内に搬入され、この加熱炉12内での搬送中に723 ℃〜
950 ℃（Ａ3 変態点以上）で高温加熱される。加熱炉12
に対しては、原管１が順次搬入されるのであり、その際
に原管１の端面間に間隔Ｌを置くことで、加熱時の原管
１の伸びや搬送速度差によって端面どうしが接触（衝
突）などすることを防止し得る。なお間隔Ｌが長過ぎた
ときには効率が悪いものとなり、したがって間隔Ｌは50
0mm 以下に制御される。The raw tube 1 transferred to the end of the loading floor 10 is
Received by the roller conveyor type heating section conveyor 11,
Then, it is conveyed in the length direction. Next, the raw tube 1 is a heating furnace.
It was loaded into the heating furnace 12 and the temperature of 723 ℃
Is high temperature heating at 950 ° C. (A 3 transformation point or higher). Heating furnace 12
On the other hand, since the raw pipe 1 is sequentially loaded, by placing a space L between the end faces of the raw pipe 1 at that time, the end faces come into contact with each other due to the elongation of the raw pipe 1 at the time of heating and the difference in transport speed. (Collision) or the like can be prevented. If the interval L is too long, the efficiency is poor, so the interval L is 50
It is controlled to 0 mm or less.
Claims (2)
長さの丸形鋼管を原管として、この原管を加熱炉で加熱
し、次いで加熱した原管を丸形鋼管成形ミルで熱間成形
して精製原管とし、そして精製原管を角形鋼管成形ミル
で熱間成形して大形角形鋼管とし、この大形角形鋼管を
冷却床で冷却したのち、切断装置により端部の成形不良
部分を切断除去することを特徴とする大形角形鋼管の製
造方法。1. A predetermined diameter and plate thickness suitable for a large rectangular steel pipe,
A round round steel pipe is used as a raw pipe, this raw pipe is heated in a heating furnace, and then the heated raw pipe is hot-formed by a round steel pipe forming mill to be a purified raw pipe, and the purified raw pipe is a square steel pipe. A large square steel pipe is formed by hot forming in a forming mill.The large square steel pipe is cooled in a cooling bed, and then a defective cutting part at the end is cut and removed by a cutting device. Production method.
長さの丸形鋼管を原管として、この原管を加熱炉で加熱
し、次いで加熱した原管を丸形鋼管成形ミルで熱間成形
して大形丸形鋼管とし、そして大形丸形鋼管を冷却床で
冷却したのち、切断装置により端部の成形不良部分を切
断除去することを特徴とする大形丸形鋼管の製造方法。2. A predetermined diameter and plate thickness suitable for a large round steel pipe,
A long round steel pipe is used as a raw pipe, this raw pipe is heated in a heating furnace, and then the heated raw pipe is hot-formed by a round steel pipe forming mill into a large round steel pipe, and then a large round steel pipe. A method for producing a large round steel pipe, which comprises cooling a steel pipe in a cooling bed, and then cutting and removing a poorly formed end portion by a cutting device.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09905195A JP3202145B2 (en) | 1995-04-25 | 1995-04-25 | Manufacturing method of large square steel pipe and large round steel pipe |
| TW085102754A TW302309B (en) | 1995-04-25 | 1996-03-06 | The manufacturing method for square and round steel pipe |
| KR1019960007390A KR100213424B1 (en) | 1995-04-25 | 1996-03-19 | Manufacturing method of square or rectangular-shaped steel pipes and manufacturing method of round-shaped steel pipes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP09905195A JP3202145B2 (en) | 1995-04-25 | 1995-04-25 | Manufacturing method of large square steel pipe and large round steel pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH08294722A true JPH08294722A (en) | 1996-11-12 |
| JP3202145B2 JP3202145B2 (en) | 2001-08-27 |
Family
ID=14236789
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP09905195A Expired - Lifetime JP3202145B2 (en) | 1995-04-25 | 1995-04-25 | Manufacturing method of large square steel pipe and large round steel pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3202145B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5802903A (en) * | 1997-01-28 | 1998-09-08 | Nakajima Steel Pipe Co., Ltd | Manufacturing method for angled steel pipes |
| JP2007301574A (en) * | 2006-05-09 | 2007-11-22 | Nakajima Steel Pipe Co Ltd | Steel tube manufacturing method, and steel tube manufacturing facility |
| CN110681924A (en) * | 2019-10-31 | 2020-01-14 | 广船国际有限公司 | Manufacturing process for end part of flat-bulb steel |
| CN112872079A (en) * | 2020-12-27 | 2021-06-01 | 黄嘉欣 | Aluminum profile machining system and method |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102861766B (en) * | 2012-09-20 | 2015-04-01 | 衡阳华菱钢管有限公司 | Square tube rolling device, square tube sizing mill with same and production method of square tube |
-
1995
- 1995-04-25 JP JP09905195A patent/JP3202145B2/en not_active Expired - Lifetime
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5802903A (en) * | 1997-01-28 | 1998-09-08 | Nakajima Steel Pipe Co., Ltd | Manufacturing method for angled steel pipes |
| JP2007301574A (en) * | 2006-05-09 | 2007-11-22 | Nakajima Steel Pipe Co Ltd | Steel tube manufacturing method, and steel tube manufacturing facility |
| CN110681924A (en) * | 2019-10-31 | 2020-01-14 | 广船国际有限公司 | Manufacturing process for end part of flat-bulb steel |
| CN112872079A (en) * | 2020-12-27 | 2021-06-01 | 黄嘉欣 | Aluminum profile machining system and method |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3202145B2 (en) | 2001-08-27 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JPH08294722A (en) | Production of large sized square steel tube and large sized round steel tube | |
| JPH0399725A (en) | Roll forming method for large sized square steel pipe | |
| JP3311211B2 (en) | Square steel pipe straightening equipment | |
| JPH0938721A (en) | Production of square steel tube | |
| JP5019783B2 (en) | Steel pipe manufacturing method and steel pipe manufacturing equipment | |
| JP2003041345A (en) | Steel pipe of welded thin sheet and manufacturing method therefor | |
| JP2003225701A (en) | Device for continuously rolling seamless steel tube | |
| JP2852311B2 (en) | Forming method and equipment for large diameter square steel pipe | |
| JPH0999324A (en) | Manufacture of square tube | |
| JPH1071423A (en) | Square steel tube and its production | |
| JP2852310B2 (en) | Large diameter square tube forming method and equipment including heat treatment | |
| WO2020067064A1 (en) | Long steel pipe for reel method and manufacturing method for same | |
| JP2002212640A (en) | Method for producing angular steel tube | |
| JPH07265941A (en) | Manufacture of welded tube excellent in workability by rolless tube manufacturing method | |
| JP2852314B2 (en) | Method for manufacturing large-diameter rectangular steel pipe for improving corner R member quality | |
| JPH09103821A (en) | Manufacture of square steel tube | |
| JP2735411B2 (en) | Forming method and equipment for large diameter square steel pipe | |
| JPS62185830A (en) | Method for preventing longitudinal bend of small-diameter pipe material | |
| JP2852309B2 (en) | Forming method for large diameter square steel pipe | |
| JP3879207B2 (en) | Manufacturing method of welded steel pipe | |
| JPH09279241A (en) | Production of square steel tube | |
| JP3292829B2 (en) | Method of manufacturing square steel pipe | |
| JP4173142B2 (en) | Cooling method for heated steel pipe | |
| JPH05309412A (en) | Forming method for large diameter square steel tube | |
| JP3274082B2 (en) | Steel pipe manufacturing method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| R250 | Receipt of annual fees |
Free format text: JAPANESE INTERMEDIATE CODE: R250 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120622 Year of fee payment: 11 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20150622 Year of fee payment: 14 |
|
| EXPY | Cancellation because of completion of term |