JPS6353248B2 - - Google Patents
Info
- Publication number
- JPS6353248B2 JPS6353248B2 JP23280483A JP23280483A JPS6353248B2 JP S6353248 B2 JPS6353248 B2 JP S6353248B2 JP 23280483 A JP23280483 A JP 23280483A JP 23280483 A JP23280483 A JP 23280483A JP S6353248 B2 JPS6353248 B2 JP S6353248B2
- Authority
- JP
- Japan
- Prior art keywords
- steel pipe
- steel
- length
- scale
- coiled
- 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
Links
- 229910000831 Steel Inorganic materials 0.000 claims description 53
- 239000010959 steel Substances 0.000 claims description 53
- 238000005096 rolling process Methods 0.000 claims description 18
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 239000003638 chemical reducing agent Substances 0.000 claims description 7
- 238000000034 method Methods 0.000 claims description 7
- 238000004804 winding Methods 0.000 claims description 2
- 238000005261 decarburization Methods 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 5
- 230000003647 oxidation Effects 0.000 description 5
- 238000007254 oxidation reaction Methods 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 229910052760 oxygen Inorganic materials 0.000 description 4
- 238000012545 processing Methods 0.000 description 4
- 229910000975 Carbon steel Inorganic materials 0.000 description 3
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 3
- 239000010962 carbon steel Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 230000001590 oxidative effect Effects 0.000 description 3
- 239000001301 oxygen Substances 0.000 description 3
- 229910000851 Alloy steel Inorganic materials 0.000 description 2
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 229910000677 High-carbon steel Inorganic materials 0.000 description 2
- 238000000137 annealing Methods 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 229910052804 chromium Inorganic materials 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 230000008602 contraction Effects 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910052750 molybdenum Inorganic materials 0.000 description 1
- 238000012805 post-processing Methods 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/10—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies
Landscapes
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
- Heat Treatment Of Articles (AREA)
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、焼鈍することなく二次加工でき、し
かも管内面にスケールのない、長尺のコイル状鋼
管の製造方法に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for manufacturing a long coiled steel pipe which can be subjected to secondary processing without annealing and which has no scale on the inner surface of the pipe.
（従来技術）
シームレス鋼管、電縫鋼管、鍛接鋼管、熱間押
出鋼管などを熱間ストレツチレデユーサで絞り圧
延した小径鋼管が各種配管、機械構造物、熱交チ
ユーブ等に広く用いられている。これら小径鋼管
は、ストレツチレデユーサで加工された後、後工
程および製品輸送上の問題から５〜15m程度の長
さに切断されている。加工後の最小径は、10mmφ
程度まで可能とされている。(Prior technology) Small-diameter steel pipes made by reducing and rolling seamless steel pipes, ERW steel pipes, forge welded steel pipes, hot extruded steel pipes, etc. using hot stretch reducers are widely used in various piping, mechanical structures, heat exchanger tubes, etc. . These small-diameter steel pipes are processed using a stretch reducer and then cut into lengths of about 5 to 15 m due to problems in post-processing and product transportation. The minimum diameter after processing is 10mmφ
It is possible to some extent.
従来の小径鋼管を前記各種用途に用いる場合、
長さ不足のため継手等による接続を要すること、
切捨てにより使用歩留が低下すること等長さに関
する問題点があり、小径鋼管の長尺コイル化が望
まれていた。また、小径鋼管を延伸加工するに際
しても、延伸後の両端にオフゲージ部が生じるこ
と、素管の切換作業が必要なこと等のため、長尺
コイル化が要望されていた。 When using conventional small-diameter steel pipes for the various applications mentioned above,
Due to insufficient length, connection using fittings etc. is required;
There are problems with the length, such as a decrease in usage yield due to truncation, and it has been desired to convert small diameter steel pipes into long coils. Furthermore, when drawing small-diameter steel pipes, there has been a demand for long coils because off-gauge parts occur at both ends after drawing, and it is necessary to switch the raw pipes.
従来のコイル状鋼管としては、鍛接鋼管をコイ
ル巻きしたものが特開昭50−16657号公報によつ
て知られている。該公報の発明は、本出願人の出
願したものであるが、コイル状鋼管内面の酸化ス
ケールを除去するのがむずかしい等の問題があ
る。 As a conventional coiled steel pipe, a coil-wound forge-welded steel pipe is known from Japanese Patent Application Laid-Open No. 16657/1983. Although the invention disclosed in this publication was filed by the present applicant, there are problems such as difficulty in removing oxidized scale from the inner surface of the coiled steel pipe.
非鉄金属やステンレス鋼においては、冷間引抜
き後コイル巻きし、光輝焼鈍したものが使用され
ている。また、普通鋼では、電縫溶接後コイル巻
きしたものがあり、これを焼鈍したあと延伸して
フラツクス入り溶接ワイヤ等が製造されている。 Nonferrous metals and stainless steels are cold drawn, coiled, and bright annealed. Furthermore, some common steels are coil-wound after electric resistance welding, and are then annealed and stretched to produce flux-cored welding wires and the like.
（発明の目的）
本発明は焼鈍することなく二次加工でき、しか
も、管内面にスケールのない長尺のコイル状鋼管
を製造することを目的とする。(Objective of the Invention) An object of the present invention is to manufacture a long coiled steel pipe that can be subjected to secondary processing without annealing and has no scale on the inner surface of the pipe.
（発明の構成、作用）
本発明は、鋼管をストレツチレデユーサにより
熱間絞り圧延し、該圧延をAr1点以上の温度で終
了させ、ついでコイルに巻取り放冷することを特
徴とするコイル状鋼管の製造方法である。(Structure and operation of the invention) The present invention is characterized in that a steel pipe is hot-reduced by a stretch reducer, the rolling is finished at a temperature of one Ar point or higher, and then it is wound into a coil and left to cool. This is a method for manufacturing a coiled steel pipe.
対象とする鋼管は、低炭素鋼、高炭素鋼、低合
金鋼のいずれでもよく、マンネスマン各種方式に
よるシームレス鋼管、熱間押出鋼管、電縫鋼管、
鍛接鋼管等を用いることができる。 The target steel pipes may be low carbon steel, high carbon steel, or low alloy steel, including seamless steel pipes manufactured by various Mannesmann methods, hot extruded steel pipes, electric resistance welded steel pipes,
A forge-welded steel pipe or the like can be used.
酸化性雰囲気で加熱し、絞り圧延した場合、鋼
管の外面には酸化スケールが生じるが、製品の二
次加工工程において、必要に応じて容易にデスケ
ーリングすることができる。鋼管内には、加熱前
は空気が入つているので、加熱によつて鋼管内面
に酸化スケールが生じる。しかし、本発明法のよ
うに、オーステナイト相（γ相）が生成する温度
域に加熱して絞り圧延すると、鋼管の先端部は急
激に酸化されるとともに、圧延により管端が閉そ
くして空気の侵入が阻止されるか、あるいは閉そ
くしなくても空気が侵入し難くなるので、管内の
酸素分圧が低下する。一方、鋼管の組織中のγ相
は鋼中炭素の拡散速度が大きいので鋼は脱炭され
やすい状態になつている。したがつて、鋼管先端
のある長さ以降の部分では、鋼管の内面において
は酸化速度が脱炭速度より小となり、酸化スケー
ルが生成せず、さらに、加熱前に存在していたス
ケールが鋼中の炭素によつて還元される。 When heated in an oxidizing atmosphere and subjected to reduction rolling, oxide scale is generated on the outer surface of the steel pipe, but it can be easily descaled as necessary in the secondary processing of the product. Since air is contained within the steel pipe before heating, oxidized scale is generated on the inner surface of the steel pipe due to heating. However, when the steel pipe is heated to a temperature range where the austenite phase (γ phase) is generated and subjected to reduction rolling as in the method of the present invention, the tip of the steel pipe is rapidly oxidized, and the end of the pipe is closed due to rolling, allowing air to escape. The oxygen partial pressure inside the tube is reduced because the intrusion is prevented or it becomes difficult for air to infiltrate even without occlusion. On the other hand, since the γ phase in the structure of the steel pipe has a high diffusion rate of carbon in the steel, the steel is easily decarburized. Therefore, beyond a certain length at the tip of the steel pipe, the oxidation rate is lower than the decarburization rate on the inner surface of the steel pipe, and oxide scale is not generated, and furthermore, the scale that existed before heating is removed from the steel. is reduced by carbon.
なお、絞り圧延する前に鋼管を燃焼式の加熱炉
で加熱する場合、炉内雰囲気は酸素分圧が低く、
CO／CO2比が高く、重油だきの場合CO＝2.2％、
CO2＝14％、O2＝1.5％の例があるように脱炭さ
れやすい条件となる。したがつて炉内で管内がこ
のような雰囲気で配置されると鋼管先端の酸化も
抑えられる。 Note that when steel pipes are heated in a combustion-type heating furnace before reduction rolling, the atmosphere inside the furnace has a low oxygen partial pressure.
The CO/CO 2 ratio is high; CO = 2.2% when using heavy oil;
For example, CO 2 = 14% and O 2 = 1.5%, which are conditions that facilitate decarburization. Therefore, if the inside of the tube is placed in such an atmosphere in the furnace, oxidation of the tip of the steel tube can be suppressed.
鋼管後端部のある長さ部分については、後端が
開放されている場合には、絞り圧延後の冷却時
に、管内のガスの収縮によつて空気が侵入して酸
素分圧が高くなり、酸化スケールが生成すること
がある。しかし、酸化速度が脱炭速度より小とな
るように空気の侵入を抑えてやるか、還元により
生じるCOガスの濃度を高める等の対策により酸
化スケールの生成を抑えることができる。 Regarding a certain length of the rear end of the steel pipe, if the rear end is open, air will enter due to the contraction of the gas in the pipe during cooling after reduction rolling, increasing the oxygen partial pressure. Oxidized scale may form. However, the formation of oxide scale can be suppressed by suppressing the intrusion of air so that the oxidation rate is lower than the decarburization rate, or by increasing the concentration of CO gas generated by reduction.
ストレツチレデユーサによる絞り圧延におい
て、Ar1点以上の温度で圧延を終了させ、巻取り
放冷すると、冷却中にγ→αの変態が完了し、完
全な焼鈍組織となる。 In reduction rolling using a stretch reducer, when the rolling is finished at a temperature of Ar 1 or higher, and the material is coiled and allowed to cool, the transformation from γ to α is completed during cooling, resulting in a completely annealed structure.
ストレツチレデユーサによる絞り圧延において
は、管の先端部および後端部に肉厚の厚いオフゲ
ージ部が生じるので、これを切断除去する。した
がつて、先後端部のスケール発生領域が、このオ
フゲージ部の長さ以内になるように条件を設定す
ることにより全長にわたつて内面酸化スケールの
ないコイル状鋼管を製造することができる。 In reduction rolling using a stretch reducer, thick off-gauge parts are generated at the tip and rear ends of the tube, and these are cut and removed. Therefore, by setting conditions such that the scale generation area at the leading and trailing ends is within the length of this off-gauge section, it is possible to manufacture a coiled steel pipe free of internal oxidation scale over the entire length.
なお、加熱炉の雰囲気を非酸化性にしてやれ
ば、鋼管の外面および先後端部内面の酸化スケー
ル生成が抑制されるが、絞り圧延の雰囲気を非酸
化性にすることは困難であり、外面については後
工程でのデスケーリングが容易であること、内面
については前述のように先後端のある長さ以外は
酸化スケールが生成しないことから、特にその必
要はない。 Note that if the atmosphere in the heating furnace is made non-oxidizing, the formation of oxide scale on the outer surface and inner surface of the leading and trailing ends of the steel pipe will be suppressed, but it is difficult to make the atmosphere for reducing rolling non-oxidizing, and This is not particularly necessary because descaling is easy in the subsequent process, and oxide scale is not generated on the inner surface except for a certain length at the leading and trailing ends as described above.
また、脱炭が問題となるような高炭素鋼管を製
造する場合は、絞り圧延終了後に脱炭温度域を急
冷する等の対策により、製品の材質上の問題は回
避することができる。 Furthermore, when manufacturing high-carbon steel pipes where decarburization is a problem, problems with the material quality of the product can be avoided by taking measures such as rapid cooling in the decarburization temperature range after the completion of reduction rolling.
（実施例）
(1) Ｃ：0.05％、Si：0.01％、Mn：0.3％、の炭
素鋼からなり、外径89.1mmφ、肉厚2.8mm、長
さ77mの電縫鋼管を燃焼式バレル炉で1000℃に
加熱し、21スタンドのストレツチレデユーサ
で、外径13.8mmφ、肉厚2.3mmに絞り圧延し、
コイル内径730mmφで巻取り、コイル状鋼管を
製造した。絞り圧延終了温度は750℃、巻取温
度は730℃とした。(Example) (1) An electric resistance welded steel tube made of carbon steel with C: 0.05%, Si: 0.01%, Mn: 0.3%, outer diameter 89.1 mmφ, wall thickness 2.8 mm, and length 77 m was heated in a combustion barrel furnace. The material was heated to 1000℃ and rolled to an outer diameter of 13.8mmφ and wall thickness of 2.3mm using a 21-stand stretch reducer.
A coiled steel pipe was manufactured by winding the coil with an inner diameter of 730 mmφ. The reduction rolling end temperature was 750°C, and the coiling temperature was 730°C.
先端部約7m、後端部約10mのオフゲージを
切拾てたコイル状鋼管全長約700mの内面には
スケールがなく、組織は完全焼鈍組織であり、
機械的性質は、引張強さ30Kg／mm2、降伏点20
Kg／mm2、全伸び55％であつた。 The inner surface of a coiled steel tube with a total length of about 700 m, which was cut off from off-gauge with a tip part of about 7 m and a rear end of about 10 m, has no scale and the structure is a completely annealed structure.
Mechanical properties are tensile strength 30Kg/mm 2 and yield point 20
Kg/mm 2 and total elongation was 55%.
(2) Ｃ：0.40％、Si：0.24％、Mn：0.77％の炭素
鋼からなり、外径89.1mmφ、肉厚7.5mm、長さ
59mの電縫鋼管を熱間絞り圧延し、外径25.4
mm、肉厚6.0mm、長さ300mのコイル状鋼管を製
造した。絞り圧延終了温度は730℃とした。(2) Made of carbon steel with C: 0.40%, Si: 0.24%, Mn: 0.77%, outer diameter 89.1mmφ, wall thickness 7.5mm, length
59m long ERW steel pipe is hot drawn and has an outer diameter of 25.4mm.
A coiled steel pipe with a length of 300 m and a wall thickness of 6.0 mm was manufactured. The reduction rolling end temperature was 730°C.
先後端のオフゲージ部を切拾てた後のコイル
状鋼管の内面にはスケールがなく、組織は完全
焼鈍組織であり、機械的性質は、引張長さ69
Kg／mm2、降伏点42Kg／mm2、全伸び35％であつ
た。 There is no scale on the inner surface of the coiled steel pipe after cutting off the off-gauge part at the tip and rear end, the structure is a completely annealed structure, and the mechanical properties are as follows: tensile length 69
Kg/mm 2 , yield point 42 Kg/mm 2 , and total elongation 35%.
(3) Ｃ：0.22％、Si：0.25％、Mn：0.52％の炭素
鋼からなり、外径89.1mmφ、肉厚4.0mm、長さ
25mのシームレス鋼管を熱間絞り圧延し、外径
25.4mmφ、肉厚2.5mm、長さ145mのコイル状鋼
管を製造した。絞り圧延終了温度は730℃とし
た。(3) Made of carbon steel with C: 0.22%, Si: 0.25%, Mn: 0.52%, outer diameter 89.1mmφ, wall thickness 4.0mm, length
A 25m seamless steel pipe is hot-drawn and the outer diameter
A coiled steel pipe with a diameter of 25.4mm, a wall thickness of 2.5mm, and a length of 145m was manufactured. The reduction rolling end temperature was 730°C.
先後端のオフゲージ部を切拾てた後のコイル
状鋼管の内面にはスケールがなく、組織は完全
焼鈍組織であり、機械的性質は、引張強さ52
Kg／mm2、降伏点40Kg／mm2、全伸び50％であつ
た。 There is no scale on the inner surface of the coiled steel pipe after cutting off the off-gauge part at the tip and rear end, the structure is a completely annealed structure, and the mechanical properties are tensile strength of 52
Kg/mm 2 , yield point 40 Kg/mm 2 , and total elongation 50%.
(4) Ｃ：0.29％、Si：0.28％、Mn：0.49％、Cr：
0.92％、Mo：0.17％の低合金鋼からなり、外
径89.1mmφ、肉厚7.5mm、長さ8.5mの熱間押出
鋼管を熱間絞り圧延し、外径25.4mmφ、肉厚
6.0mm、長さ40mのコイル状鋼管を製造した。
絞り圧延終了温度は730℃とした。(4) C: 0.29%, Si: 0.28%, Mn: 0.49%, Cr:
Made of low-alloy steel with 0.92% and Mo: 0.17%, hot extruded steel tube with outer diameter 89.1 mmφ, wall thickness 7.5 mm, and length 8.5 m is hot-reduced and rolled to have an outer diameter 25.4 mmφ and wall thickness.
A coiled steel pipe with a diameter of 6.0 mm and a length of 40 m was manufactured.
The reduction rolling end temperature was 730°C.
先後端のオフゲージ部を切捨てた後のコイル
状鋼管の内面にはスケールがなく、組織は完全
焼鈍組織であり、機械的性質は、引張強さ74
Kg／mm2、降伏点63Kg／mm2、全伸び33％であつ
た。 There is no scale on the inner surface of the coiled steel pipe after cutting off the off-gauge part at the tip and rear end, the structure is a completely annealed structure, and the mechanical properties are tensile strength of 74.
Kg/mm 2 , yield point 63 Kg/mm 2 , and total elongation 33%.
（発明の効果）
本発明により、外径約10mmφまで、長さ700m
程度までの長尺で内面酸化スケールがなく、焼鈍
組織を有するコイル状鋼管が製造できる。このた
め、各種配管工事において、従来のような管の接
続がほとんど不要となる。また、機械構造物、熱
交チユーブ等の製造においては、必要長さだけ切
取ることができるので、切捨量がほとんどなくな
る。さらに、延伸加工においては、管端オフゲー
ジによる歩留低下がなく、また生産性が向上する
等の効果がある。(Effect of the invention) According to the present invention, the outer diameter is up to about 10 mmφ and the length is 700 m.
It is possible to manufacture coiled steel pipes that are long to a certain extent, have no internal oxidation scale, and have an annealed structure. Therefore, in various piping works, there is almost no need for conventional pipe connections. Furthermore, in the manufacture of mechanical structures, heat exchanger tubes, etc., only the required length can be cut, so there is almost no need to cut off the material. Furthermore, in the drawing process, there is no decrease in yield due to off-gauge at the tube end, and there are effects such as improved productivity.
Claims (1)
圧延し、該圧延をAr1点以上の温度で終了させ、
ついでコイルに巻取り放冷することを特徴とする
コイル状鋼管の製造方法。1 Hot-reducing-rolling a steel pipe using a stretch reducer, finishing the rolling at a temperature of Ar 1 point or higher,
A method for manufacturing a coiled steel pipe, which comprises: then winding it into a coil and leaving it to cool.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23280483A JPS60125326A (en) | 1983-12-12 | 1983-12-12 | Production of coiled steel pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP23280483A JPS60125326A (en) | 1983-12-12 | 1983-12-12 | Production of coiled steel pipe |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60125326A JPS60125326A (en) | 1985-07-04 |
| JPS6353248B2 true JPS6353248B2 (en) | 1988-10-21 |
Family
ID=16945023
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP23280483A Granted JPS60125326A (en) | 1983-12-12 | 1983-12-12 | Production of coiled steel pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60125326A (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63242404A (en) * | 1987-03-31 | 1988-10-07 | Nippon Steel Corp | Manufacture of coiled special shape tube |
| JP3855300B2 (en) * | 1996-04-19 | 2006-12-06 | 住友金属工業株式会社 | Manufacturing method and equipment for seamless steel pipe |
-
1983
- 1983-12-12 JP JP23280483A patent/JPS60125326A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60125326A (en) | 1985-07-04 |
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| LAPS | Cancellation because of no payment of annual fees |