JP3336925B2 - Pipe end thick steel pipe manufacturing method - Google Patents
Pipe end thick steel pipe manufacturing methodInfo
- Publication number
- JP3336925B2 JP3336925B2 JP25159397A JP25159397A JP3336925B2 JP 3336925 B2 JP3336925 B2 JP 3336925B2 JP 25159397 A JP25159397 A JP 25159397A JP 25159397 A JP25159397 A JP 25159397A JP 3336925 B2 JP3336925 B2 JP 3336925B2
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- JP
- Japan
- Prior art keywords
- steel pipe
- thick
- pipe
- steel
- manufacturing
- 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.)
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Description
【０００１】[0001]
【発明の属する技術分野】この発明は、アプセット加工
により鋼管の管端に厚肉部を形成する管端厚肉鋼管の製
造方法、特に鋼管の長さが短くて、通常のアプセット加
工では管端に厚肉部を形成することが困難な管端厚肉鋼
管の製造方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a thick-walled steel pipe in which a thick portion is formed at the pipe end of the steel pipe by upset processing. The present invention relates to a method for manufacturing a pipe end thick steel pipe in which it is difficult to form a thick wall portion.
【０００２】[0002]
【従来の技術】設計上の理由から鋼管の管端の肉厚を、
鋼管の外径を同じくして、中央部分よりも厚くする場合
には、通常図２（ａ）および図２（ｂ）に示すような、
アプセット加工により、管端に厚肉部を形成するように
している。すなわち、外径を同じくした鋼管管端のアプ
セット加工においては、図２（ａ）に示すように、鋼管
２１管端外面に、鋼管２１の外径とほぼ同じ内径を有す
るグリップダイス２２および加工ダイス２３を装着させ
るとともに、鋼管２１の内面には、管端から厚肉部形成
用ツ−ル２４の挿入部２４ａを挿入させる。2. Description of the Related Art For design reasons, the wall thickness of a steel pipe end is reduced.
In the case where the outer diameter of the steel pipe is made the same and the steel pipe is made thicker than the central part, usually, as shown in FIGS. 2 (a) and 2 (b),
A thick portion is formed at the pipe end by upset processing. That is, in the upset processing of a steel pipe end having the same outer diameter, as shown in FIG. 2A, a grip die 22 having an inner diameter substantially equal to the outer diameter of the steel pipe 21 and a processing die are provided on the outer surface of the steel pipe 21 pipe end. At the same time, the insertion part 24a of the thick part forming tool 24 is inserted into the inner surface of the steel pipe 21 from the pipe end.
【０００３】厚肉部形成用ツ−ル２４は、管端に厚肉部
が形成されたときの管端内径と同じ外径Ｄaを有する挿
入部２４ａと、外径Ｄbが鋼管２１の外径Ｄと同じ圧縮
部２４ｂと、押圧部２４ｃとから構成されている。[0003] thick portion forming tools - le 24 includes an insertion portion 24a having the same outer diameter D a and the pipe end inside diameter when the thick portion is formed on the pipe end, the outer diameter D b of the steel pipe 21 It is composed of a compression portion 24b having the same outer diameter D and a pressing portion 24c.
【０００４】そして、前記グリップダイス２２を鋼管２
１の外面に密着させて、加工ダイス２３が鋼管２１の長
さ方向にずれないようにした上で、押圧部２４ｃに油圧
等により圧力を加えることにより、厚肉部形成用ツ−ル
２４を鋼管２１の内面に押し込んでいく。[0004] The grip die 22 is connected to the steel pipe 2.
The tool 24 for forming the thick portion is formed by applying pressure to the pressing portion 24c with a hydraulic pressure or the like after making the working die 23 not to be displaced in the longitudinal direction of the steel pipe 21 by being brought into close contact with the outer surface of the steel tube 21. It is pushed into the inner surface of the steel pipe 21.
【０００５】厚肉部形成用ツ−ル２４を鋼管２１の内面
に押し込んでいくと、圧縮部２４ｂにより、鋼管２１の
管端が圧縮されるので、鋼管２１の管端の肉厚は徐々に
厚くなっていき、厚肉部形成用ツ−ル２４が完全に押し
込まれた時点では、図２（ｂ）に示すように、鋼管２１
の管端には、内周面が厚肉部形成用ツ−ル２４の挿入部
２４ａの外周面に接触するほどの厚肉部２１ａが形成さ
れる。When the tool 24 for forming the thick part is pushed into the inner surface of the steel pipe 21, the end of the steel pipe 21 is compressed by the compression part 24b, so that the thickness of the pipe end of the steel pipe 21 is gradually reduced. When the tool 24 for forming the thick part is completely pushed in, the steel pipe 21 is formed as shown in FIG.
At the end of the tube, a thick portion 21a is formed such that the inner peripheral surface contacts the outer peripheral surface of the insertion portion 24a of the thick portion forming tool 24.
【０００６】しかしながら、長さが一定長さよりも短い
鋼管の管端に、中央部分よりも肉厚が厚い厚肉部を、ア
プセット加工により、形成させようとしても、アプセッ
ト加工設備の設備上の制約から、厚肉部を形成させるこ
とが困難となる場合がある。However, even if an attempt is made to form a thick-walled portion having a greater thickness than the central portion at the pipe end of a steel pipe having a length shorter than a certain length by upset processing, there is a restriction on the facilities of the upset processing equipment. Therefore, it may be difficult to form a thick portion.
【０００７】このような場合には、図３（ａ）に示すよ
うに、肉厚ｔが必要とされる管端の肉厚と同じ鋼管２１
の中央部分２５を斜線で示すように切削して減厚するこ
とにより、図３（ｂ）に示すように、管端に厚肉部２１
ａを形成するようにしている。In such a case, as shown in FIG. 3A, a steel pipe 21 having a wall thickness t equal to the required wall thickness at the pipe end is required.
The central portion 25 of the tube is cut as shown by oblique lines to reduce the thickness, so that a thick portion 21 is formed at the pipe end as shown in FIG.
a is formed.
【０００８】[0008]
【発明が解決しようとする課題】しかしながら、上述し
た従来の短尺の鋼管の管端に厚肉部を形成させる方法
は、製造に時間がかかるとともに、鋼管の歩留をも低下
させることになり、製造コストがアップするという問題
点があった。However, the above-mentioned conventional method of forming a thick portion at the end of a short steel pipe requires a long time for production and also reduces the yield of the steel pipe. There is a problem that the manufacturing cost increases.
【０００９】この発明は、従来技術の上述のような問題
点を解消するためになされたものであり、アプセット加
工により短尺の鋼管の管端に厚肉部を形成させることが
できるので、加工に時間がかからないとともに、鋼管の
歩留も低下しない管端厚肉鋼管の製造方法を提供するこ
とを目的としている。The present invention has been made to solve the above-mentioned problems of the prior art, and a thick wall portion can be formed at the end of a short steel pipe by upset processing. An object of the present invention is to provide a method for manufacturing a pipe-end thick steel pipe that does not take much time and does not reduce the yield of the steel pipe.
【００１０】[0010]
【課題を解決するための手段】この発明に係る管端厚肉
鋼管の製造方法は、外径が一定で管端の肉厚が管中央部
の肉厚よりも厚い管端厚肉鋼管を、アプセット加工によ
り製造する管端厚肉鋼管の製造方法において、アプセッ
ト加工により鋼管の管端に厚肉部を形成させ、この鋼管
を厚肉部以外の部分で２本に切断した後、切断した鋼管
の厚肉部同士を突き合わせて溶接することにより、厚肉
部を鋼管の両端部以外に少なくとも１ケ所以上形成さ
せ、この鋼管の管端に厚肉部を形成させた後、鋼管の管
端部以外に形成させた厚肉部の中央部分を切断すること
により、１本の鋼管から少なくとも２本以上の管端厚肉
鋼管を製造するものである。According to the present invention, there is provided a method for manufacturing a pipe-end thick steel pipe having a constant outer diameter and a pipe end having a wall thickness larger than a wall thickness of a pipe center portion. In the method for manufacturing a pipe end thick steel pipe manufactured by upset processing, a thick wall portion is formed at the pipe end of the steel pipe by upset processing, and this steel pipe is cut into two portions other than the thick wall portion, and then the cut steel pipe is cut. The thick portions are formed in at least one place other than both ends of the steel pipe by butt-welding the thick portions to form a thick portion at the pipe end of the steel pipe, and then the pipe end of the steel pipe is formed. By cutting the central part of the thick part formed other than the above, at least two or more pipe end thick steel pipes are manufactured from one steel pipe.
【００１１】この管端厚肉鋼管の製造方法においては、
厚肉部を鋼管の両端部以外に少なくとも１ケ所以上形成
させ、このような厚肉部の中央部を最終的に切断して、
最初の鋼管よりも短い管端厚肉鋼管を製造するようにし
ているので、アプセット加工するときの鋼管の長さは、
常に最初の鋼管の長さとほとんど変わらず、従来アプセ
ット加工が不可とされた長さの短い管端厚肉鋼管の製造
が可能となる。[0011] In this method of manufacturing a thick-walled steel pipe,
A thick part is formed at least at one or more places other than both ends of the steel pipe, and a central part of such a thick part is finally cut,
Since the end of the steel pipe is made thicker than the first steel pipe, the length of the steel pipe when upsetting is
The length of the steel pipe is almost the same as the length of the initial steel pipe, and a short-walled steel pipe having a short length at which the upset processing is conventionally impossible is made possible.
【００１２】[0012]
【発明の実施の形態】本発明の実施の形態の管端厚肉鋼
管の製造方法を、図１により説明する。図１（ａ）〜
（ｉ）は、この管端厚肉鋼管の製造方法において、長尺
の鋼管から短尺の管端厚肉鋼管を３本製造する場合の製
造工程図である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A method for manufacturing a pipe end thick steel pipe according to an embodiment of the present invention will be described with reference to FIG. FIG. 1 (a)-
(I) is a manufacturing process diagram in a case of manufacturing three short tube-end thick steel pipes from a long steel pipe in the method of manufacturing the pipe-end thick steel pipe.
【００１３】（１）図１（ａ）に示すように、十分にア
プセット加工可能な長尺鋼管１に、アプセット加工を施
し、図１（ｂ）に示すように、両管端に厚肉部２ａおよ
び２ｂを有する長尺鋼管２とする。(1) As shown in FIG. 1 (a), a long steel pipe 1 which can be sufficiently upset is subjected to upset processing, and as shown in FIG. A long steel pipe 2 having 2a and 2b.
【００１４】（２）図１（ｃ）に示すように、両管端に
厚肉部２ａおよび２ｂを有する長尺鋼管２を、一端から
全長Ｌ1の１／３の長さの位置Ａで切断し、長短２本の
鋼管３および４とする。(2) As shown in FIG. 1 (c), a long steel pipe 2 having thick portions 2a and 2b at both ends is placed at a position A which is １ ／ of the total length L1 from one end. It is cut into two long and short steel pipes 3 and 4.
【００１５】（３）図１（ｄ）に示すように、長短２本
の鋼管３および４のそれぞれの厚肉部２ａおよび２ｂが
形成されている管端同士を突き合わせ、溶接線５で示す
ように溶接し、全長の１／３の位置に厚肉部２ａおよび
２ｂが形成されている長尺鋼管６とする。(3) As shown in FIG. 1D, the ends of the two long and short steel pipes 3 and 4 where the thick portions 2a and 2b are formed are abutted to each other. To form a long steel pipe 6 having thick portions 2a and 2b formed at one third of the entire length.
【００１６】（４）全長の１／３の位置に厚肉部２ａお
よび２ｂが形成されている長尺鋼管６に、アプセット加
工を施し、図１（ｅ）に示すように、両管端に厚肉部７
ａおよび７ｂを有し、かつ全長の１／３の位置に厚肉部
２ａおよび２ｂが形成されている長尺鋼管７とする。(4) An upset process is performed on the long steel pipe 6 having the thick portions 2a and 2b formed at one third of the entire length, and as shown in FIG. Thick part 7
a and 7b, and the thick steel portions 2a and 2b are formed at one-third of the total length.
【００１７】（５）両管端に厚肉部７ａおよび７ｂを有
し、かつ全長の１／３の位置に厚肉部２ａおよび２ｂが
形成されている長尺鋼管７を、図１（ｆ）に示すよう
に、前記（２）項で切断したときの長い方の鋼管３を２
等分する位置Ｂ、すなわち長尺鋼管７の全長Ｌ2の１／
３の位置で切断し、長短２本の鋼管８および９とする。(5) A long steel pipe 7 having thick portions 7a and 7b at both ends and having thick portions 2a and 2b formed at one third of the entire length is shown in FIG. 1 (f). ), The longer steel pipe 3 cut at the time of the item (2) is
Equal position B, that is, 1/1 of the total length L 2 of the long steel pipe 7
At the position of No. 3, two long and short steel pipes 8 and 9 are obtained.
【００１８】（６）図１（ｇ）に示すように、長短２本
の鋼管８および９のそれぞれの厚肉部７ａおよび７ｂが
形成されている管端同士を突き合わせ、溶接線１０で示
すように溶接し、一端から全長の１／３の位置に厚肉部
２ａおよび２ｂが形成され、他端から全長の１／３の位
置に厚肉部７ａおよび７ｂが形成されている長尺鋼管１
１とする。(6) As shown in FIG. 1 (g), the ends of the two long and short steel pipes 8 and 9 where the thick portions 7a and 7b are formed are abutted to each other. A long steel pipe 1 in which thick portions 2a and 2b are formed at one-third of the total length from one end and thick portions 7a and 7b are formed at one-third of the total length from the other end.
Let it be 1.
【００１９】（７）図１（ｈ）に示すように、一端から
全長の１／３の位置に厚肉部２ａおよび２ｂが形成さ
れ、他端から全長の１／３の位置に厚肉部７ａおよび７
ｂが形成されている長尺鋼管１１に、アプセット加工を
施し、両管端に厚肉部１２ａおよび１２ｂが形成されて
いる長尺鋼管１２とする。(7) As shown in FIG. 1 (h), thick portions 2a and 2b are formed at one-third of the total length from one end, and thick portions at one-third of the total length from the other end. 7a and 7
The long steel pipe 11 on which b is formed is subjected to upset processing to obtain a long steel pipe 12 having thick portions 12a and 12b formed at both ends.
【００２０】（８）図１（ｉ）に示すように、長尺鋼管
１２を溶接線５および１０の近傍で切断（溶接部を含ま
ないように切断）し、３本の長さの等しい短尺の鋼管１
３、１４および１５とする。(8) As shown in FIG. 1 (i), the long steel pipe 12 is cut in the vicinity of the welding lines 5 and 10 (cut so as not to include the welded portion), and three short steel pipes having the same length are cut. Steel pipe 1
3, 14, and 15.
【００２１】上述のようにして製造した短尺鋼管１３の
両端には、肉厚部１２ａと７ｂが、短尺鋼管１４の両端
には、肉厚部７ａと２ｂが、短尺鋼管１５の両端には、
肉厚部２ａと１２ｂが形成される。At both ends of the short steel tube 13 manufactured as described above, thick portions 12a and 7b are provided, at both ends of the short steel tube 14, thick portions 7a and 2b are provided, and at both ends of the short steel tube 15,
Thick portions 2a and 12b are formed.
【００２２】なお、図１（ｅ）に示す長尺鋼管７を、厚
肉部２ａおよび２ｂを接続した溶接線５の位置で切断す
れば、２本の長さの異なる短尺の管端厚肉鋼管となる。
また、図１（ｃ）に示す切断位置Ａを、全長Ｌ1の１／
２とすると、同じ長さの２本の短尺の管端厚肉鋼管を得
ることができる。If the long steel pipe 7 shown in FIG. 1 (e) is cut at the position of the welding line 5 connecting the thick parts 2a and 2b, two short pipe end thick parts having different lengths are cut. It becomes a steel pipe.
Further, the cutting position A shown in FIG. 1 (c), the total length L 1 1 /
If it is set to 2, two short pipe-end thick steel pipes having the same length can be obtained.
【００２３】すなわち、アプセット加工−切断−溶接と
いう工程を繰り返し、かつ切断位置を適宜選定すること
により、任意の長さの短尺の管端厚肉鋼管を、必要な本
数だけ得ることができる。That is, by repeating the steps of upset-cutting-welding and appropriately selecting the cutting position, it is possible to obtain the required number of short pipe-end thick steel pipes having an arbitrary length.
【００２４】本発明の管端厚肉鋼管の製造方法において
は、短尺の管端厚肉鋼管が上述のように、アプセット加
工により製造できるので、従来の厚肉鋼管の長さ方向中
央部の肉厚を切削により減厚させてできる管端厚肉鋼管
よりも、加工時間が短くてすみ、かつ鋼管の歩留を低下
させることもないので、厚肉鋼管の製造費を低減するこ
とができる。In the method of manufacturing a thick-walled steel pipe according to the present invention, since a short-sized thick-walled steel pipe can be manufactured by upset processing as described above, the thickness of the conventional thick-walled steel pipe at the center in the longitudinal direction is increased. Since the processing time is shorter and the yield of the steel pipe is not reduced as compared with a pipe-end thick steel pipe whose thickness is reduced by cutting, the manufacturing cost of the thick steel pipe can be reduced.
【００２５】[0025]
【発明の効果】この発明により、短尺の管端厚肉鋼管が
アプセット加工により製造できるので、短尺の管端厚肉
鋼管が安価に製造できる。According to the present invention, a short pipe-end thick steel pipe can be manufactured by upset processing, so that a short pipe-end thick steel pipe can be manufactured at low cost.
【図１】本発明の実施の形態の管端厚肉鋼管の製造方法
の説明図であり、（ａ）〜（ｉ）はその製造工程図であ
る。BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory view of a method of manufacturing a pipe end thick steel pipe according to an embodiment of the present invention, and (a) to (i) are manufacturing process diagrams thereof.
【図２】従来の外径一定の管端厚肉鋼管をアプセット加
工により製造する方法の説明図であり、（ａ）は加工
前、（ｂ）は加工後の状態を示す。2A and 2B are explanatory views of a conventional method of manufacturing a thick-walled steel pipe having a constant outer diameter by upset processing, wherein FIG. 2A shows a state before processing and FIG. 2B shows a state after processing.
【図３】従来の短尺管端厚肉鋼管の製造方法の説明図で
あり、（ａ）は減厚前の鋼管の縦断面図であり、（ｂ）
は減厚後の管端厚肉鋼管の縦断面図である。FIG. 3 is an explanatory view of a conventional method for producing a short pipe end thick steel pipe, in which (a) is a longitudinal sectional view of the steel pipe before thickness reduction, and (b).
FIG. 3 is a vertical cross-sectional view of a thick-walled steel pipe having a reduced pipe end.
１ アプセット加工前の長尺鋼管 ２ 第１回目のアプセット後の長尺鋼管 ２ａ、２ｂ 第１回目のアプセット加工により形成され
た管端厚肉部 ３ 切断された長い方の鋼管 ４ 切断された短い方の鋼管 ５ 溶接線 ６ 溶接後の長尺鋼管 ７ 第２回目のアプセット後の長尺鋼管 ７ａ、７ｂ 第２回目のアプセット加工により形成され
た管端厚肉部 ８ 切断された長い方の鋼管 ９ 切断された短い方の鋼管 １０ 溶接線 １１ 溶接後の長尺鋼管 １２ 第３回目のアプセット後の長尺鋼管 １２ａ、１２ｂ 第３回目のアプセット加工により形成
された管端厚肉部 １３、１４、１５ 短尺の管端厚肉鋼管Reference Signs List 1 long steel pipe before upset processing 2 long steel pipe after first upset processing 2a, 2b Tube end thick part formed by first upsetting processing 3 Longer cut steel pipe 4 cut short Steel pipe 5 welding line 6 long steel pipe after welding 7 long steel pipe after second upset 7a, 7b thick pipe end formed by second upset processing 8 cut long steel pipe 9 Shorter cut steel pipe 10 Welding line 11 Long steel pipe after welding 12 Long steel pipe after third upset 12a, 12b Thick pipe end portion formed by third upset processing 13, 14 , 15 Short pipe end thick steel pipe
フロントページの続き (56)参考文献 特開 昭63−149038（ＪＰ，Ａ) 特開 昭63−115643（ＪＰ，Ａ) 特開 昭60−166137（ＪＰ，Ａ) 特開 昭60−54241（ＪＰ，Ａ) 特開 昭54−131564（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) B21J 1/00 - 13/14 B21J 17/00 - 19/04 B21K 1/00 - 31/00 Continuation of the front page (56) References JP-A-63-149038 (JP, A) JP-A-63-115643 (JP, A) JP-A-60-166137 (JP, A) JP-A-60-54241 (JP) , A) JP-A-54-131564 (JP, A) (58) Fields investigated (Int. Cl. 7 , DB name) B21J 1/00-13/14 B21J 17/00-19/04 B21K 1/00 -31/00
Claims (1)
厚よりも厚い管端厚肉鋼管を、アプセット加工により製
造する管端厚肉鋼管の製造方法において、アプセット加
工により鋼管の管端に厚肉部を形成させ、この鋼管を厚
肉部以外の部分で２本に切断した後、切断した鋼管の厚
肉部同士を突き合わせて溶接することにより、厚肉部を
鋼管の両端部以外に少なくとも１ケ所以上形成させ、こ
の鋼管の管端に厚肉部を形成させた後、鋼管の管端部以
外に形成させた厚肉部の中央部分を切断することによ
り、１本の鋼管から少なくとも２本以上の管端厚肉鋼管
を製造することを特徴とする管端厚肉鋼管の製造方法。1. A method for manufacturing a pipe-end thick steel pipe in which a pipe-end thick-walled steel pipe having a constant outer diameter and a pipe end having a wall thickness greater than a wall thickness of a pipe center portion is manufactured by upset processing. A thick portion is formed at a pipe end of the steel pipe, and the steel pipe is cut into two portions at portions other than the thick portion, and the thick portions of the cut steel pipe are butt-welded to each other to weld the thick portion. After forming a thick portion at the pipe end of the steel pipe, and cutting the central portion of the thick part formed at a part other than the pipe end of the steel pipe, 1 A method for manufacturing a pipe-end thick steel pipe, comprising manufacturing at least two or more pipe-end thick steel pipes from the steel pipes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25159397A JP3336925B2 (en) | 1997-09-17 | 1997-09-17 | Pipe end thick steel pipe manufacturing method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP25159397A JP3336925B2 (en) | 1997-09-17 | 1997-09-17 | Pipe end thick steel pipe manufacturing method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1190578A JPH1190578A (en) | 1999-04-06 |
| JP3336925B2 true JP3336925B2 (en) | 2002-10-21 |
Family
ID=17225134
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP25159397A Expired - Fee Related JP3336925B2 (en) | 1997-09-17 | 1997-09-17 | Pipe end thick steel pipe manufacturing method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3336925B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5648950B2 (en) * | 2009-12-03 | 2015-01-07 | 日本ヒューム株式会社 | Steel pipe concrete composite pipe |
| CN104588998A (en) * | 2015-01-26 | 2015-05-06 | 内蒙古包钢钢联股份有限公司 | Manufacturing method for short-pitch external thickened oil pipe with upset pipe ends |
| CN114515811B (en) * | 2022-03-18 | 2024-01-26 | 湘潭大学 | Forging forming method and die for unequal-thickness hollow part plate |
-
1997
- 1997-09-17 JP JP25159397A patent/JP3336925B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH1190578A (en) | 1999-04-06 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20020709 |
|
| LAPS | Cancellation because of no payment of annual fees |