JP4165025B2 - Pipe conveyor - Google Patents

Pipe conveyor Download PDF

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Publication number
JP4165025B2
JP4165025B2 JP2001077454A JP2001077454A JP4165025B2 JP 4165025 B2 JP4165025 B2 JP 4165025B2 JP 2001077454 A JP2001077454 A JP 2001077454A JP 2001077454 A JP2001077454 A JP 2001077454A JP 4165025 B2 JP4165025 B2 JP 4165025B2
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Prior art keywords
pipe
roller
caliber
bending
line
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JP2001077454A
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JP2002273523A (en
Inventor
崇生 弓手
進 板谷
隆彦 佐伯
伊佐夫 広
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JFE Steel Corp
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JFE Steel Corp
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Description

【0001】
【発明の属する技術分野】
本発明はパイプ搬送装置に関し、さらに詳しくはシーム接合管製造ラインの途中でパイプにS字形の曲げ・曲げ戻しを施して搬送するラインの搬送ローラに関する。
【0002】
【従来の技術】
シーム接合鋼管には、電縫鋼管や拡散接合鋼管などの種類がある。電縫鋼管は次のようにして製造される。まず、コイルから巻戻されたスケルプ(鋼帯)を成形ミルで管状に成形し、シーム部を接合機で溶接接合する。次いで、溶接接合で生成した溶接ビードを刃物で切削した後、所定の長さに切断し、管内に残留している溶接ビードの切削屑を除去する。その後、加熱装置で所定温度に加熱し、レデューサーミルで所定径に縮径圧延して中間製品とする。一方、拡散接合鋼管の場合は、コイルから巻戻されたスケルプを加熱炉で加熱し、成形ミルで管状に成形し、シーム部を接合機で拡散接合する。拡散接合で生成する溶接ビードは小さいため、これの切削は行わずに、ローラで圧下するなどの平滑化処理を施して、レデューサーミルによる縮径加工まで連続処理し、その後に所定長さに切断することになる。
【0003】
このように電縫鋼管と拡散接合鋼管ではそれらの製造工程が異なるため、別々の製造ラインで製造するのが通常である。しかしながら、両者の製造ラインでは共通する装置も多いことから、2つの製造ラインを1ラインに統合して2種類のシーム接合鋼管を製造できればコスト上有利となる。
【0004】
そこで、本出願人は先に、パイプ製造ラインを上流、中流及び下流の3つに分け、上流ラインと下流ラインは共通ラインとし、中流ラインを電縫鋼管と拡散接合鋼管用の2系列とした上で、この中流ラインの2系列のそれぞれに鋼管を振り分け搬送する鋼管の搬送経路切替技術を特願2000−226872号にて提供した。
【0005】
すなわち、上流ラインに対してオフセットされた下流ラインへ鋼管を2系列で搬送する中流ラインにおいて、一方はシーム部を接合された電縫鋼管の溶接ビードを切削し、切断し、ビード屑を除去して下流ラインに搬送する系列、他方はシーム部を接合された拡散接合鋼管を連続的に下流ラインに搬送する系列である。
【0006】
ここで、電縫鋼管の場合には、上流ラインから真っ直ぐに搬送されてきた鋼管を所定長さに切断等して鋼管長手方向と直角方向にシフトして下流ラインに搬送すれぱよいが、拡散接合鋼管の場合には、鋼管が連続しているので、鋼管をS字状に曲げて上流ラインから下流ラインに搬送する必要があゑそのため、中流ラインの拡散接合鋼管系列では、鋼管をS字状に曲げるための複数のパイプ曲げローラを備えている。
【0007】
従来、このS字形にパイプを曲げるために多数の円筒形のパイプ曲げローラを用いている。この搬送系路ではS字形に曲げる部分の曲率半径を、搬送されるパイプの表面歪みがその降伏ひずみ以下となるような大きさにしている。しかし、円筒形のパイプ曲げローラはパイプ外面と一点で接するので、局部的にパイプを押圧する。このためパイプがパイプ曲げローラとの接触部分で変形し、パイプ断面が偏平になったり、パイプ表面にへこみ疵が発生したりする問題がある。
【0008】
この疵を防止するために、パイプ曲げローラの押し力を低減すると、パイプが所定曲率まで曲がらなくなり、パイプの搬送が困難になる。また、局部面圧低減のために、パイプ曲げローラの外径を大きくすることも考えられるが、ローラ径が必要以上に大きくなり、設備全体が大きくなるため、大幅なコストアップを招来する。
【0009】
【発明が解決しようとする課題】
本発明は、このような問題点を解決し、パイプをS字形に曲げ・曲げ戻しするためのパイプ曲げローラによって、パイプ断面が偏平になったり、パイプ表面にへこみ疵が発生したりする問題のないパイプ搬送装置を提供することを目的とする。
【0010】
【課題を解決するための手段】
本発明は上記問題点を解決するためになされたもので、その技術は、拡散接合したパイプを上流ラインから下流ラインに、2ヶ所をそれぞれ135m及び85mの範囲の曲率半径でS字形に曲げ・曲げ戻しを施して搬送する装置において、該曲げ・曲げ戻し用ローラをカリバー形ローラとし、横断面視で、対象パイプ径に応じてパイプの中心と一対のカリバー形ローラが形成するカリバーの中心とが一致するようにカリバー形ローラを上下左右にシフトするシフト装置を備えたことを特徴とするパイプ搬送装置である。
【0011】
この場合に、カリバー形ローラのカリバーの形状をパイプ外形に近似させるとパイプとローラとの接触部が広くなり接触面圧が低下するので好適である。また、前記カリバー形ローラは、パイプ径に応じてカリバーの中心をパイプ中心に一致させるシフト装置を備えパイプ径に応じてカリバーの中心をパイプ中心に一致させ
【0012】
【発明の実施の形態】
以下、本発明の実施形態について説明する。図3はパイプ製造ラインの全体を説明する説明図である。コイル101から引き出されたスケルプ102は中継機103、ルーパー104を経て加熱炉105に入り、電縫鋼管の場合には加熱されずに、拡散接合鋼管の場合には所定温度に加熱され、成形ミル106で断面が円形状曲げ加工され、接合機107でシーム部を接合されてパイプ120となる。ここまでが上流ラインである。
【0013】
電縫鋼管の場合には、パイプ120は本実施形態に係るパイプ搬送装置1によりそのまま真っ直ぐ搬送され、溶接ビードを切削装置(図示せず)で切削され、次に切断機(図示せず)で所定長さに切断された後、管軸直角方向に搬送され、更に管内に残留しているビード屑がビード屑除去装置(図示せず)で除去された後、さらに管軸直角方向に搬送されて、後述の下流ラインに供給される。パイプ120が拡散接合鋼管であれば、パイプ搬送装置1により、連続的にS字状に曲げ・曲げ戻しされて、後述の下流ラインに搬送される。中流ラインは、上記パイプ搬送装置1、溶接ビード切削装置、切断装置、及びビード屑除去装置などから構成される。
【0014】
中流ラインから搬送されてきた鋼管は下流ラインに供給されて以下の処理が施される。即ち、誘導加熱装置108で所定の熱処理が施された後、レデューサーミル109で所定の径となるように縮径圧延される。電縫鋼管の場合にはそのまま、中間製品111とされ、拡散接合鋼管の場合には、製品切断機110で所定長さに切断されて中間製品111となる。
【0015】
図2はパイプ搬送装置1の拡大説明図である。図中、122及び123はローラテーブル、124は搬送ローラであり、ローラテーブル123はローラテーブル122に対し、所定距離オフセットされている。20はパイプを曲げ・曲げ戻しするためのパイプ曲げローラであり、本実施形態では、9セットが配置されている。
【0016】
以下、拡散接合鋼管の場合について述べる。パイプ120は上流ラインからローラテーブル122上を矢印121で示すように送られて来る。まず、パイプ曲げローラ20で曲率半径R1の曲線となるように曲げられ、次にパイプ曲げローラ20で曲率半径R2の曲線となるように曲げ戻しされながら下流工程へと搬送される。
【0017】
このパイプをS字形に曲げ・曲げ戻しするパイプ曲げローラ装置20は従来円筒状のパイプ曲げローラを用いていた。図1は本発明の実施形態のパイプ曲げローラ装置20を示すものでパイプ曲げローラ21、22はカリバー形ローラ21、22とした。このカリバー形ローラ21、22はパイプ120aを挟む1対をなしており、取付枠23に装着され、空圧シリンダ24によってパイプ120aに押しつけられている。パイプのS字搬送屈曲点ではカリバー形ローラ21、22によりパイプの凹みを防止する。対象パイプが大径パイプ120aであるか小径パイプ120bであるかによって、パイプサイズに応じてパイプの中心とカリバー形ローラ21、22との中心が一致するように矢印25、26で示すようにカリバー形ローラ21、22をシフトするシフト装置(図示省略)を備えている。
【0018】
本発明のカリバー形ローラと従来の円筒形パイプ曲げローラでのパイプのへこみ発生範囲と比較すると、従来は、円筒形パイプ曲げローラの径を350mmφまで拡大しても疵の発生を防止することが出来なかったが、カリバー形ローラ採用により、ローラ底径240mmφでも疵の発生を防止出来るようになった。表1は、実機においてテストしたパイプの搬送疵の発生状況を示すものである。
【0019】
【表1】

Figure 0004165025
【0020】
局部面圧低減のためには、円筒形パイプ曲げローラ径を大きくすることによっても低減は可能であるが、カリバー形ローラとすることによる改善効果の方が大きい。
【0021】
【発明の効果】
本発明によればカリバー形ローラの採用により、曲率半径135m及び85mRの範囲での曲げ戻しではパイプヘのへこみ疵の発生も無く、安定的にパイプを所定の曲率に曲げ・曲げ戻して搬送することが可能になった。
【図面の簡単な説明】
【図1】実施例のカリバー形ローラの正面図である。
【図2】パイプ曲げ・曲げ戻し工程の説明図である。
【図3】造管工程全体の説明図である。
【符号の説明】
1 パイプ搬送装置
20 パイプ曲げローラ装置
21、22 カリバー形ローラ
23 取付枠
24 空圧シリンダ
25 矢印
26 矢印
101 コイル
102 スケルプ
103 中継
104 ルーパー
105 加熱炉
106 成形ミル
107 溶接装置
108 加熱装置
109 圧延機
110 製品切断機
111 中間製品管
120、120a、120b パイプ
121 矢印
122、123 ローラテーブル[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pipe conveying device, and more particularly to a conveying roller of a line that conveys a pipe by subjecting a pipe to S-shaped bending / bending back in the middle of a seam joint pipe manufacturing line.
[0002]
[Prior art]
There are various types of seam-bonded steel pipes, such as ERW steel pipes and diffusion-bonded steel pipes. The ERW steel pipe is manufactured as follows. First, a skelp (steel strip) unwound from a coil is formed into a tubular shape with a forming mill, and a seam portion is welded and joined with a joining machine. Next, after cutting the weld bead generated by the welding joint with a blade, it is cut to a predetermined length to remove the cutting waste of the weld bead remaining in the pipe. Then, it heats to predetermined temperature with a heating apparatus, and diameter-reduction-rolls to a predetermined diameter with a reducer mill, and is set as an intermediate product. On the other hand, in the case of a diffusion bonded steel pipe, the skelp unwound from the coil is heated in a heating furnace, formed into a tubular shape with a forming mill, and the seam portion is diffusion bonded with a bonding machine. Since the weld bead produced by diffusion bonding is small, it is not cut, but it is smoothed by rolling down with a roller, continuously processed until the diameter reduction by the reducer mill, and then cut to a predetermined length. Will do.
[0003]
As described above, since the production process is different between the electric resistance welded steel pipe and the diffusion bonded steel pipe, it is usually produced on separate production lines. However, since both production lines have many devices in common, it is advantageous in terms of cost if two types of seam-bonded steel pipes can be manufactured by integrating the two production lines into one line.
[0004]
Therefore, the applicant first divided the pipe production line into three parts, upstream, middle stream, and downstream, the upstream line and the downstream line are common lines, and the middle line is composed of two series for ERW steel pipe and diffusion bonded steel pipe. In the above, Japanese Patent Application No. 2000-226872 provided a technology for switching the transport route of a steel pipe that distributes and transports the steel pipe to each of the two lines of the midstream line.
[0005]
That is, in a midstream line that transports steel pipes in two lines to a downstream line that is offset with respect to the upstream line, one of them cuts and cuts a weld bead of an ERW steel pipe joined with a seam portion to remove bead debris. And the other is a series in which the diffusion-bonded steel pipe having the seam portion joined is continuously conveyed to the downstream line.
[0006]
Here, in the case of ERW steel pipe, the steel pipe that has been transported straight from the upstream line may be cut to a predetermined length, shifted in the direction perpendicular to the longitudinal direction of the steel pipe, and transported to the downstream line. In the case of bonded steel pipes, since the steel pipes are continuous, it is necessary to bend the steel pipes in an S shape and transport them from the upstream line to the downstream line. A plurality of pipe bending rollers for bending into a shape are provided.
[0007]
Conventionally, a large number of cylindrical pipe bending rollers are used to bend the pipe into the S shape. In this conveyance path, the radius of curvature of the portion that is bent into an S-shape is sized so that the surface strain of the pipe being conveyed is less than or equal to its yield strain. However, since the cylindrical pipe bending roller is in contact with the outer surface of the pipe at one point, the pipe is locally pressed. For this reason, there is a problem that the pipe is deformed at the contact portion with the pipe bending roller, the pipe cross-section becomes flat, and dents are generated on the pipe surface.
[0008]
If the pressing force of the pipe bending roller is reduced in order to prevent this wrinkle, the pipe will not bend to a predetermined curvature, making it difficult to convey the pipe. Although it is conceivable to increase the outer diameter of the pipe bending roller in order to reduce the local surface pressure, the roller diameter becomes larger than necessary and the entire equipment becomes larger, resulting in a significant cost increase.
[0009]
[Problems to be solved by the invention]
The present invention solves such problems, and the pipe bending roller for bending / bending the pipe into an S shape causes the pipe cross-section to become flat or dents to occur on the pipe surface. The object is to provide a pipe conveying device without.
[0010]
[Means for Solving the Problems]
The present invention has been made in order to solve the above-mentioned problems. The technique is such that a diffusion-bonded pipe is bent from an upstream line to a downstream line, and two places are bent into S-shapes with curvature radii in the range of 135 m and 85 m , respectively. In the apparatus for carrying out the bending return, the bending / returning roller is a caliber type roller, and in the cross-sectional view, the center of the pipe and the center of the caliber formed by the pair of caliber type rollers according to the target pipe diameter It is a pipe conveying device characterized by including a shift device that shifts the caliber-shaped roller up, down, left and right so as to match.
[0011]
In this case, the contact surface pressure contact portion is wider in the approximating the shape of the caliber of mosquito River shaped roller to the pipe outer the pipe and the rollers are preferred because reduced. Moreover, the caliber-shaped rollers, Ru to match the pipe around the center of the caliber in accordance with the pipe diameter a shift device to match the pipe around the center of the caliber in accordance with the pipe diameter.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described. FIG. 3 is an explanatory view illustrating the entire pipe production line. The skelp 102 drawn out from the coil 101 enters the heating furnace 105 through the relay machine 103 and the looper 104, and is not heated in the case of an electric-welded steel pipe but is heated to a predetermined temperature in the case of a diffusion-bonded steel pipe. The cross section is circularly bent at 106, and the seam portion is joined by the joining machine 107 to form the pipe 120. This is the upstream line.
[0013]
In the case of an ERW steel pipe, the pipe 120 is conveyed straight as it is by the pipe conveying device 1 according to the present embodiment, the weld bead is cut by a cutting device (not shown), and then cut by a cutting machine (not shown). After being cut to a predetermined length, it is transported in the direction perpendicular to the tube axis. Further, bead waste remaining in the tube is removed by a bead waste removal device (not shown), and further transported in the direction perpendicular to the tube axis. And supplied to the downstream line described later. If the pipe 120 is a diffusion-bonded steel pipe, it is continuously bent and bent back into an S shape by the pipe conveying device 1 and conveyed to the downstream line described later. The midstream line is composed of the pipe conveying device 1, a weld bead cutting device, a cutting device, a bead waste removing device, and the like.
[0014]
The steel pipe conveyed from the midstream line is supplied to the downstream line and subjected to the following processing. That is, after a predetermined heat treatment is performed by the induction heating device 108, the reduction mill 109 reduces the diameter to a predetermined diameter. In the case of an electric resistance steel pipe, the intermediate product 111 is used as it is, and in the case of a diffusion bonded steel pipe, the intermediate product 111 is cut into a predetermined length by a product cutting machine 110.
[0015]
FIG. 2 is an enlarged explanatory view of the pipe conveying device 1. In the figure, 122 and 123 are roller tables, 124 is a transport roller, and the roller table 123 is offset from the roller table 122 by a predetermined distance. Reference numeral 20 denotes a pipe bending roller for bending and returning the pipe. In this embodiment, 9 sets are arranged.
[0016]
Hereinafter, the case of a diffusion bonded steel pipe will be described. The pipe 120 is sent from the upstream line on the roller table 122 as indicated by an arrow 121. First, the pipe bending roller 20 is bent so as to have a curvature radius R 1 , and then the pipe bending roller 20 is conveyed back to the downstream process while being bent back to have a curvature radius R 2 .
[0017]
The pipe bending roller device 20 that bends and returns the pipe to an S shape conventionally uses a cylindrical pipe bending roller. FIG. 1 shows a pipe bending roller device 20 according to an embodiment of the present invention. The pipe bending rollers 21 and 22 are caliber-shaped rollers 21 and 22. The caliber rollers 21 and 22 form a pair sandwiching the pipe 120 a, are attached to the mounting frame 23, and are pressed against the pipe 120 a by the pneumatic cylinder 24. The caliber-shaped rollers 21 and 22 prevent the dent of the pipe at the S-shaped conveyance bending point of the pipe. Depending on whether the target pipe is a large-diameter pipe 120a or a small-diameter pipe 120b, the caliber as shown by arrows 25 and 26 so that the center of the pipe coincides with the center of the caliber-shaped rollers 21 and 22 depending on the pipe size. A shift device (not shown) for shifting the shape rollers 21 and 22 is provided.
[0018]
Compared with the dent occurrence range of the caliber-shaped roller of the present invention and the conventional cylindrical pipe bending roller, it is possible to prevent the occurrence of wrinkles even if the diameter of the cylindrical pipe bending roller is increased to 350 mmφ. Although it was not possible, the adoption of a caliber roller made it possible to prevent wrinkles even at a roller bottom diameter of 240 mm. Table 1 shows the state of occurrence of pipe transport rods tested in the actual machine.
[0019]
[Table 1]
Figure 0004165025
[0020]
In order to reduce the local surface pressure, the reduction can also be achieved by increasing the diameter of the cylindrical pipe bending roller, but the improvement effect by using the caliber type roller is greater.
[0021]
【The invention's effect】
According to the present invention, by adopting a caliber roller, when bending back in the range of curvature radii of 135m and 85mR, there is no generation of dents on the pipe, and the pipe is stably bent and bent back to a predetermined curvature and conveyed. Became possible.
[Brief description of the drawings]
FIG. 1 is a front view of a caliber roller according to an embodiment.
FIG. 2 is an explanatory diagram of a pipe bending / bending process.
FIG. 3 is an explanatory diagram of the entire pipe making process.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipe conveyance apparatus 20 Pipe bending roller apparatus 21, 22 Caliber type roller 23 Mounting frame 24 Pneumatic cylinder 25 Arrow 26 Arrow 101 Coil 102 Skelp 103 Relay 104 Looper 105 Heating furnace 106 Forming mill 107 Welding apparatus 108 Heating apparatus 109 Rolling mill 110 Product cutting machine 111 Intermediate product pipe 120, 120a, 120b Pipe 121 Arrow 122, 123 Roller table

Claims (1)

拡散接合したパイプを上流ラインから下流ラインに、2ヶ所をそれぞれ135m及び85mの範囲の曲率半径でS字形に曲げ・曲げ戻しを施して搬送する装置において、
該曲げ・曲げ戻し用ローラをカリバー形ローラとし、横断面視で、対象パイプ径に応じてパイプの中心と一対のカリバー形ローラが形成するカリバーの中心とが一致するようにカリバー形ローラを上下左右にシフトするシフト装置を備えたことを特徴とするパイプ搬送装置。
In an apparatus that conveys a diffusion-bonded pipe from an upstream line to a downstream line by bending and bending the two locations into an S shape with a radius of curvature in the range of 135 m and 85 m , respectively.
The bending / returning roller is a caliber-shaped roller, and the caliber-shaped roller is moved up and down so that the center of the pipe and the center of the caliber formed by the pair of caliber-shaped rollers coincide in accordance with the target pipe diameter in a cross-sectional view. A pipe transfer device comprising a shift device that shifts left and right.
JP2001077454A 2001-03-19 2001-03-19 Pipe conveyor Expired - Fee Related JP4165025B2 (en)

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