JP2674911B2 - Steel material for welded steel pipes with excellent wear resistance - Google Patents
Steel material for welded steel pipes with excellent wear resistanceInfo
- Publication number
- JP2674911B2 JP2674911B2 JP3259241A JP25924191A JP2674911B2 JP 2674911 B2 JP2674911 B2 JP 2674911B2 JP 3259241 A JP3259241 A JP 3259241A JP 25924191 A JP25924191 A JP 25924191A JP 2674911 B2 JP2674911 B2 JP 2674911B2
- Authority
- JP
- Japan
- Prior art keywords
- wear resistance
- steel
- excellent wear
- steel pipe
- present
- 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 - Lifetime
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- Rigid Pipes And Flexible Pipes (AREA)
- Heat Treatment Of Steel (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は石油やガスの掘削や、輸
送分野で要求される鋼管内面側の耐磨耗特性に優れた溶
接鋼管用鋼材に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steel material for welded steel pipe, which has excellent wear resistance on the inner surface of the steel pipe, which is required in the fields of oil and gas excavation and transportation.
【０００２】[0002]
【従来の技術】近年の鋼管需要において、鋼管内面側の
耐磨耗特性に対する要求が増加する傾向にある。石油や
ガスの掘削分野においては、水平掘りによる開発が盛ん
になっており、このときにドリルパイプとケーシングパ
イプの接触によるケーシングパイプ内面側の磨耗による
損傷が問題となっている。また、スラリー管等において
も管内面の耐磨耗特性を高めることが要求されている。2. Description of the Related Art In recent years, demands for steel pipes tend to increase the demand for wear resistance on the inner surface side of the steel pipes. In the field of oil and gas drilling, horizontal drilling has been actively developed, and at this time, damage due to wear on the inner surface of the casing pipe due to contact between the drill pipe and the casing pipe has become a problem. In addition, it is also required to improve the abrasion resistance of the inner surface of a slurry tube or the like.
【０００３】耐磨耗特性を向上させるには、例えば特開
昭６２−２７０７２５号公報の如く硬度を高めることが
効果的であるが、耐腐食特性や低温靭性等との両立をは
かる上で、鋼管全体を高硬度化することは好ましくな
い。また近年鋼管の表面近傍だけを硬化させるため、異
種金属やセラミックス等を溶射する技術や表面処理等を
施す方法が検討されているが、いずれも生産性の観点か
ら得策とはいえない。In order to improve the abrasion resistance, it is effective to increase the hardness as disclosed in, for example, Japanese Patent Application Laid-Open No. 62-270725, but in order to achieve compatibility with corrosion resistance and low-temperature toughness. It is not preferable to increase the hardness of the entire steel pipe. In recent years, in order to harden only the vicinity of the surface of the steel pipe, techniques of spraying different kinds of metals, ceramics, and the like, and methods of performing surface treatment and the like have been studied.
【０００４】[0004]
【発明が解決しようとする課題】本発明は上記の欠点を
解消し、内面側の耐磨耗特性に優れた溶接鋼管用鋼材を
提供するものである。DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned drawbacks and provides a steel material for welded steel pipe having excellent wear resistance on the inner surface side.
【０００５】[0005]
【課題を解決するための手段】本発明の要旨とする処
は、外層成分材が、Ｃ：０．２〜０．６wt％、Ｍｎ：
０．１〜３．０wt％を基本成分とした耐磨耗特性に優れ
た高炭素成分の低合金鋼とし、内層成分材をＣ：０．０
１〜０．３wt％、Ｍｎ：０．１〜３．０wt％を基本成分
とし、Ｎｂ：０．０１〜０．１０wt％、Ｖ：０．０１〜
０．１０wt％、Ｍｏ：０．０５〜０．５０wt％、Ｔｉ：
０．００５〜０．１０wt％の１種または２種以上を含有
した低合金鋼からなる耐磨耗特性に優れた溶接鋼管用鋼
材にある。According to the gist of the present invention, the outer layer component material is C: 0.2 to 0.6 wt% and Mn:
A low-alloy steel with a high carbon content and a basic component of 0.1-3.0 wt% and excellent wear resistance, with C: 0.0
1 to 0.3 wt%, Mn: 0.1 to 3.0 wt% as a basic component, Nb: 0.01 to 0.10 wt%, V: 0.01 to
0.10 wt%, Mo: 0.05 to 0.50 wt%, Ti:
A steel material for a welded steel pipe, which is made of a low alloy steel containing 0.005 to 0.10 wt% of one kind or two or more kinds and has excellent wear resistance.
【０００６】複層スラブの製造方法としては周知の連続
鋳造法、造塊法などの鋳造方法によればよく、例えば特
開昭６３−１０８９４７号公報に記載されている連続鋳
造方法によって複層鋼材としてもよく、その手段は特に
こだわるものでない。[0006] The method for producing the multilayer slab may be a known casting method such as a continuous casting method or an ingot casting method. For example, a multilayer steel material may be produced by the continuous casting method described in JP-A-63-108947. The means is not particularly particular.
【０００７】複層スラブとは、図１に示すように、外層
部１と内層部２の成分が異なるスラブ３である。本発明
では、外層部１を内層部２よりも高Ｃ系成分として、耐
磨耗特性を高めることにより、鋼全体を硬化させること
なく、効果的に耐磨耗特性を高めることが可能となる。
また、この時の外層部の厚みｔは、最終製品の厚みによ
って適宜設定することができるが、一般的には、全厚み
ｗの５％〜２０％程度が適当である。As shown in FIG. 1, a multilayer slab is a slab 3 in which the components of the outer layer 1 and the inner layer 2 are different. In the present invention, the outer layer portion 1 is made to have a higher C-based component than the inner layer portion 2 so as to enhance the wear resistance, so that the wear resistance can be effectively increased without hardening the entire steel. .
Further, the thickness t of the outer layer portion at this time can be appropriately set according to the thickness of the final product, but generally, about 5% to 20% of the total thickness w is suitable.
【０００８】以下に本発明について詳細に説明する。本
発明は、外層成分材を耐磨耗特性に優れた高炭素成分の
低合金鋼とした複層スラブを利用することが大きなポイ
ントとなる。このとき内層成分材を、比較的低炭素成分
材とすることによって全体の強度の必要以上の上昇を回
避することが可能となり、また、耐腐食特性や低温靭性
との両立が可能となる。Hereinafter, the present invention will be described in detail. The major point of the present invention is to utilize a multi-layer slab in which the outer layer component material is a low carbon steel having a high carbon content and excellent wear resistance. At this time, by making the inner layer component material a relatively low carbon component material, it is possible to avoid an unnecessary increase in the overall strength, and it is possible to achieve both corrosion resistance and low temperature toughness.
【０００９】また、本発明の複層鋼材は、熱間圧延後の
鋼帯の表裏両面に耐磨耗特性を付与でき、とくに鋼帯を
多条にスリットして製造する電縫鋼管の場合には、表裏
面の指定を考慮する必要がない。一方、従来の片面側の
みの複層鋼板の場合は、内面側を耐磨耗材層とするため
に表裏面の指定が必要となり、特別のスリット方法など
を考慮する必要が生ずる。Further, the multi-layer steel material of the present invention can impart abrasion resistance to both front and back surfaces of a steel strip after hot rolling, and particularly in the case of an electric resistance welded steel pipe produced by slitting the steel strip into multiple strips. Does not need to consider the designation of the front and back sides. On the other hand, in the case of a conventional multi-layer steel sheet having only one side, it is necessary to specify the front and back sides in order to make the inner surface side a wear resistant material layer, and it is necessary to consider a special slit method or the like.
【００１０】次に、本発明における鋼の成分の限定理由
について説明する。外層成分材の成分は、高硬度による
耐磨耗特性をねらったものである。熱間圧延および圧延
後の冷却条件、または製管後の管体熱処理条件が同じ場
合、得られる硬度はそのＣ量に支配されるといわれてい
る。本発明の耐磨耗鋼管では硬度をビッカース硬度で３
００ポイント以上を狙うものであり、その点からＣ量は
０．２％以上必要である。一方、Ｃ量が０．６％を超え
ると熱間圧延の際の割れや鋼管成形時の割れをきたす。Next, the reasons for limiting the steel components in the present invention will be described. The components of the outer layer component material are intended for wear resistance due to high hardness. It is said that the obtained hardness is governed by the C content when the hot rolling and the cooling conditions after the rolling or the tube heat treatment conditions after the pipe making are the same. The wear-resistant steel pipe of the present invention has a hardness of 3 in Vickers hardness.
The aim is to achieve 00 points or more, and from that point, the C content must be 0.2% or more. On the other hand, if the C content exceeds 0.6%, cracking occurs during hot rolling and cracking during forming of a steel pipe.
【００１１】Ｍｎも硬度の上昇に寄与する。Ｍｎ量の下
限０．１wt％より低い量では硬化能力が小さく、かつ製
鋼コストが高くなるためで、一方、Ｍｎ量が３％を超え
ると鋼管成形性が劣化し、かつコストが高くなる。Mn also contributes to an increase in hardness. When the amount of Mn is lower than the lower limit of 0.1 wt%, the hardening ability is small and the steelmaking cost becomes high. On the other hand, when the amount of Mn exceeds 3%, the steel pipe formability deteriorates and the cost becomes high.
【００１２】Ｎｂ，Ｖ，Ｍｏ，Ｔｉ，Ｃｕ，Ｎｉ，Ｃ
ｒ，Ｂの添加は本発明の必須の条件ではないが、これら
の元素の添加は組織の微細化や焼入れ性の向上に寄与す
るので、選択的に添加することは本発明の主旨に反しな
い。また、脱酸を目的としたＡｌ，Ｓｉの添加や、非金
属介在物の形態制御を目的としたＣａ，Ｚｒの添加も本
発明の主旨に反しない。Nb, V, Mo, Ti, Cu, Ni, C
Although the addition of r and B is not an essential condition of the present invention, since the addition of these elements contributes to the refinement of the structure and the improvement of hardenability, the selective addition does not depart from the gist of the present invention. . Further, addition of Al and Si for the purpose of deoxidation and addition of Ca and Zr for the purpose of controlling the form of nonmetallic inclusions do not contradict the gist of the present invention.
【００１３】内層成分材の成分は、油井用鋼管や、スラ
リー管（ラインパイプ）としての基本性能を維持するこ
とを前提としたものである。Ｃは強度を得るのに必要な
元素で、Ｃ量が０．０１wt％未満では十分な強度が得ら
れない。一方、Ｃ量が０．３wt％を超えると耐腐食特性
や低温靭性の確保が困難となる。The components of the inner layer component material are based on the premise that the basic performance of an oil well steel pipe or a slurry pipe (line pipe) is maintained. C is an element necessary for obtaining strength. If the amount of C is less than 0.01% by weight, sufficient strength cannot be obtained. On the other hand, if the C content exceeds 0.3% by weight, it becomes difficult to ensure corrosion resistance and low-temperature toughness.
【００１４】Ｍｎも強度を得るのに必要な元素で、Ｍｎ
量の下限０．１wt％より低い量では強化能力が小さく、
かつ製鋼コストが高くなる。一方、Ｍｎ量が３％を超え
ると鋼管成形性が劣化し、かつコストが高くなり、また
中心偏析部が硬化し、耐腐食特性や低温靭性を劣化させ
る。Mn is also an element necessary for obtaining strength.
If the lower limit of the amount is less than 0.1 wt%, the strengthening ability is small,
Moreover, the steelmaking cost becomes high. On the other hand, if the Mn content exceeds 3%, the steel pipe formability deteriorates, the cost increases, and the central segregation portion hardens, deteriorating the corrosion resistance and low temperature toughness.
【００１５】さらに、組織の微細化や、強度上昇の目的
で、Ｎｂ，Ｖ，Ｍｏ，Ｔｉの１種または２種以上を添加
することが有効である。Further, it is effective to add one or more of Nb, V, Mo, and Ti for the purpose of refining the structure and increasing the strength.
【００１６】Ｎｂは熱間圧延時のオーステナイト粒の微
細化に効果的であり、その後の変態により生成するフェ
ライト粒の微細化をもたらし、耐腐食性の向上や、低温
靭性の向上に有効である。このようなＮｂ添加効果を得
るには、０．０１wt％以上の添加が必要である。また、
０．１０wt％を超えて添加しても効果は変わらないた
め、上限は０．１％とした。Nb is effective for refining austenite grains during hot rolling, and also refining ferrite grains generated by subsequent transformation, and is effective for improving corrosion resistance and low temperature toughness. . In order to obtain such an Nb addition effect, it is necessary to add 0.01 wt% or more. Also,
The effect does not change even if added in excess of 0.10 wt%, so the upper limit was made 0.1%.
【００１７】Ｖはフェライト変態後に炭窒化物として析
出し、フェライト粒の粗大化を抑制する効果と、析出物
による強化の効果をもつ。Ｖ量の下限０．０１wt％より
低い量では、効果がなく、一方Ｖ量が０．１０wt％を超
えても効果は変わらないため、上限は、０．１０wt％と
した。V precipitates as carbonitrides after ferrite transformation, and has the effect of suppressing coarsening of ferrite grains and the effect of strengthening by the precipitates. If the amount of V is lower than the lower limit of 0.01 wt%, there is no effect. On the other hand, if the amount of V exceeds 0.10 wt%, the effect does not change, so the upper limit was made 0.10 wt%.
【００１８】Ｍｏは固溶強化元素として強度確保に有効
であり、耐腐食特性や低温靭性の劣化を伴わずに強度を
高めるのに有効な元素である。Ｍｏ量の下限の０．０５
wt％より低い量では強化能力が小さい。一方、Ｍｏ量
が、０．５０wt％を超えると必要以上に強度が上昇し、
かつコストが高くなる。Mo is a solid solution strengthening element that is effective for ensuring strength, and is an element that is effective for increasing strength without deterioration of corrosion resistance and low temperature toughness. Mo content lower limit of 0.05
When the amount is lower than wt%, the strengthening ability is small. On the other hand, when the Mo content exceeds 0.50 wt%, the strength increases more than necessary,
And the cost is high.
【００１９】Ｔｉは、炭窒化物として析出し、熱間圧延
前のスラブ再加熱時のオーステナイト粒の粗大化を抑制
する効果や、フェライト変態後のフェライト粒の粗大化
を抑制する効果をもつ。Ｔｉ量の下限０．００５wt％よ
り低い量では、効果がなく、一方、Ｔｉ量が０．１０wt
％を超えても効果は変わらないため、上限は、０．１０
wt％とした。Ti is precipitated as carbonitride and has an effect of suppressing coarsening of austenite grains during slab reheating before hot rolling, and an effect of suppressing coarsening of ferrite grains after ferrite transformation. When the amount of Ti is lower than the lower limit of 0.005 wt%, no effect is obtained, while the amount of Ti is 0.10 wt%.
Even if it exceeds%, the effect does not change, so the upper limit is 0.10.
wt%.
【００２０】Ｃｕ，Ｎｉ，Ｂの添加は本発明の必須の条
件ではないが、これらの元素の添加は強度の上昇や焼入
れ性の向上に寄与するので、選択的に添加することは本
発明の主旨に反しない。Although the addition of Cu, Ni and B is not an essential condition of the present invention, the addition of these elements contributes to the increase of strength and the improvement of hardenability. It does not violate the spirit.
【００２１】脱酸を目的としたＡｌ，Ｓｉの添加や、非
金属介在物の形態制御を目的としたＣａ，Ｚｒの添加は
本発明の主旨に反するものではない。The addition of Al and Si for the purpose of deoxidation and the addition of Ca and Zr for the purpose of controlling the morphology of non-metallic inclusions are not contrary to the gist of the present invention.
【００２２】また、耐腐食特性の改善や低温靭性の改善
の目的で、できるだけＰ，Ｓの有害元素は低減すること
が望ましい。以上のような成分を有する複層鋼材を利用
することにより、耐磨耗特性に優れた溶接鋼管を得るこ
とができる。Further, it is desirable to reduce harmful elements of P and S as much as possible for the purpose of improving corrosion resistance and improving low temperature toughness. By using the multi-layer steel material having the above components, a welded steel pipe having excellent wear resistance can be obtained.
【００２３】[0023]
【実施例】表１のＡ，Ｂ，Ｃ，Ｄが本発明の実施例であ
る。Ａ，Ｂ，Ｃ，Ｄの複層スラブを圧延後、製造した鋼
管は、外層部が効果的に硬化しており、鋼管全体の硬度
（強度）を必要以上に高めることなく、耐磨耗特性に優
れた鋼管が得られている。一方、表１のＥ，Ｆは、本発
明に対する比較材の単層鋼管の例である。Ｅは、炭素含
有量は多いものの、硬度が不十分である。また、Ｆは、
硬度が高く耐磨耗特性には優れているものの、管全体の
硬度（強度）は必要以上に高く、実用上適さない。EXAMPLES A, B, C and D in Table 1 are examples of the present invention. After rolling the multi-layer slab of A, B, C and D, the outer layer portion of the steel pipe manufactured is effectively hardened, and the wear resistance characteristics are not increased without increasing the hardness (strength) of the entire steel pipe more than necessary. An excellent steel pipe is obtained. On the other hand, E and F in Table 1 are examples of single-layer steel pipes as comparative materials for the present invention. E has a large carbon content, but has insufficient hardness. Also, F is
Although it has high hardness and excellent abrasion resistance, the hardness (strength) of the entire tube is unnecessarily high and is not suitable for practical use.
【００２４】[0024]
【表１】 [Table 1]
【００２５】[0025]
【発明の効果】本発明は、鋼管全体の硬度（強度）を必
要以上に高めることなく耐磨耗特性に優れた鋼管を製造
可能にした。また、本発明の生産性は高く、且つ製造コ
ストも安価で、産業上極めて大きな効果が期待される。INDUSTRIAL APPLICABILITY The present invention makes it possible to manufacture a steel pipe having excellent wear resistance characteristics without increasing the hardness (strength) of the entire steel pipe more than necessary. Further, the productivity of the present invention is high, and the manufacturing cost is low, so that an extremely large effect in industry is expected.
【図１】複層スラブの概観を示した斜視図である。FIG. 1 is a perspective view showing an overview of a multilayer slab.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 昭51−130618（ＪＰ，Ａ) 特開 昭51−98629（ＪＰ，Ａ) 特開 昭57−192243（ＪＰ，Ａ) ─────────────────────────────────────────────────── ─── Continuation of front page (56) References JP-A-51-130618 (JP, A) JP-A-51-98629 (JP, A) JP-A-57-192243 (JP, A)
Claims (1)
金鋼とし、内層成分材を Ｃ ：０．０１〜０．３wt％ Ｍｎ：０．１〜３．０wt％ を基本成分とし、 Ｎｂ：０．０１〜０．１０wt％ Ｖ ：０．０１〜０．１０wt％ Ｍｏ：０．０５〜０．５０wt％ Ｔｉ：０．００５〜０．１０wt％ の１種または２種以上を含有した低合金鋼からなること
を特徴とする耐磨耗特性に優れた溶接鋼管用鋼材。1. A low-alloy steel having a high carbon content and excellent wear resistance characteristics, wherein the outer layer constituent material is C: 0.2 to 0.6 wt% Mn: 0.1 to 3.0 wt% as a basic component, The inner layer component material is C: 0.01 to 0.3 wt% Mn: 0.1 to 3.0 wt% as a basic component, and Nb: 0.01 to 0.10 wt% V: 0.01 to 0.10 wt% Mo : 0.05 to 0.50 wt% Ti: 0.005 to 0.10 wt% A low alloy steel containing one or two or more types, and a steel material for welded steel pipes excellent in wear resistance characteristics. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3259241A JP2674911B2 (en) | 1991-10-07 | 1991-10-07 | Steel material for welded steel pipes with excellent wear resistance |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3259241A JP2674911B2 (en) | 1991-10-07 | 1991-10-07 | Steel material for welded steel pipes with excellent wear resistance |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0598390A JPH0598390A (en) | 1993-04-20 |
| JP2674911B2 true JP2674911B2 (en) | 1997-11-12 |
Family
ID=17331372
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3259241A Expired - Lifetime JP2674911B2 (en) | 1991-10-07 | 1991-10-07 | Steel material for welded steel pipes with excellent wear resistance |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2674911B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102330850A (en) * | 2011-08-05 | 2012-01-25 | 昆明理工大学 | Bimetal centrifugal composite pipe and preparation method thereof |
| JP5375981B2 (en) | 2012-01-10 | 2013-12-25 | Ｊｆｅスチール株式会社 | Wear-resistant welded steel pipe with excellent weld crack resistance and method for producing the same |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5198629A (en) * | 1975-02-27 | 1976-08-31 | YOSETSUSEIGARYOKODETAIMAMOSEINO SUGURETANISOKAN | |
| JPS51130618A (en) * | 1975-05-08 | 1976-11-13 | Kubota Ltd | Abration-resistant 2-layered pipe with good weldability |
-
1991
- 1991-10-07 JP JP3259241A patent/JP2674911B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0598390A (en) | 1993-04-20 |
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Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 19970617 |