JP3379345B2 - Method for producing 13Cr stainless steel tube having oxide layer - Google Patents

Method for producing 13Cr stainless steel tube having oxide layer

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Publication number
JP3379345B2
JP3379345B2 JP22246396A JP22246396A JP3379345B2 JP 3379345 B2 JP3379345 B2 JP 3379345B2 JP 22246396 A JP22246396 A JP 22246396A JP 22246396 A JP22246396 A JP 22246396A JP 3379345 B2 JP3379345 B2 JP 3379345B2
Authority
JP
Japan
Prior art keywords
scale
stainless steel
steel pipe
outer layer
rolling
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 - Fee Related
Application number
JP22246396A
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Japanese (ja)
Other versions
JPH1060538A (en
Inventor
敏朗 安楽
伸夫 大塚
康善 日高
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Sumitomo Metal Industries Ltd
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Application filed by Sumitomo Metal Industries Ltd filed Critical Sumitomo Metal Industries Ltd
Priority to JP22246396A priority Critical patent/JP3379345B2/en
Publication of JPH1060538A publication Critical patent/JPH1060538A/en
Application granted granted Critical
Publication of JP3379345B2 publication Critical patent/JP3379345B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

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Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【発明の属する技術分野】本発明は、耐食性と表面粗さ
に優れた酸化層を有する13Cr系ステンレス鋼管の製
造方法に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a 13Cr stainless steel pipe having an oxide layer excellent in corrosion resistance and surface roughness.

【0002】[0002]

【従来の技術】継目無鋼管は、ピアサー穿孔圧延により
ビレットを中空素管とし、その後中空素管を延伸圧延す
ることにより製造される。延伸圧延方法としては、寸法
精度および生産性で優れているマンドレルミル圧延法が
広く利用されている。マンドレルミルにより圧延された
中空素管は一般的に仕上げ圧延用素管と呼ばれる。
2. Description of the Related Art A seamless steel pipe is manufactured by forming a billet into a hollow shell by piercing and piercing rolling, and then stretching and rolling the hollow shell. As a stretching and rolling method, a mandrel mill rolling method, which is excellent in dimensional accuracy and productivity, is widely used. A hollow shell rolled by a mandrel mill is generally called a finish rolling shell.

【0003】仕上げ圧延用素管は、必要に応じて再加熱
炉によって所定温度(850℃から1100℃)に再加
熱された後ストレッチレデューサー等の仕上げ圧延機に
より所定サイズに延伸され、900℃以上から焼入れ、
次いで700℃近傍での焼戻しをへて、ショットブラス
トさらに硫酸又は硝沸酸による酸洗脱スケールを実施し
た後出荷される。焼入れについては、仕上げ圧延後に放
冷しないでそのまま、又は温度を均一化する補熱を行っ
た後、直接焼入れする方法も行われる。
The finish rolling stock tube is reheated to a predetermined temperature (850 ° C. to 1100 ° C.) by a reheating furnace, if necessary, and then stretched to a predetermined size by a finish rolling machine such as a stretch reducer, and at least 900 ° C. Quenching,
Then, after being tempered at around 700 ° C., shot blasting, and pickling and descaling with sulfuric acid or nitric acid are carried out before shipment. As for quenching, there is also used a method of directly quenching after finishing rolling without cooling, or after supplementary heat for equalizing the temperature.

【0004】上述のように継目無鋼管の製造においては
被圧延材であるビレット、中空素管、又は仕上げ圧延用
素管のそれぞれが、1300℃〜700℃の加熱を受け
るため、管の内外表面には不可避的にスケールが形成さ
れる。本明細書において、鋼表面に形成される酸化層を
スケールと呼ぶが、剥離しやすいスケール外層を除去し
た後、密着性の良好な鋼表面に残ったスケール内層の部
分を“酸化層”と称して区別する場合がある。
As described above, in the production of the seamless steel pipe, each of the billet, the hollow shell, and the finish rolling stock pipe, which are the materials to be rolled, is heated at 1300 ° C. to 700 ° C., so that the inner and outer surfaces of the pipe are A scale is inevitably formed on the surface. In the present specification, the oxide layer formed on the steel surface is referred to as a scale, but after removing the scale outer layer that is easily peeled off, the portion of the scale inner layer remaining on the steel surface having good adhesion is referred to as an “oxide layer”. May be distinguished.

【0005】このスケールは部分的に剥離したりする
と、熱間圧延時において圧延ロールによる押し込み傷に
なるため通常各圧延工程前に高圧水等によるデスケーリ
ングが実施されている。また、焼入れ処理および焼戻し
処理で生成したスケールは、上述のショットおよび酸洗
により除去されるが、地金との密着力が強固であるため
長時間の酸洗が必要となる。このため、高効率のショッ
トブラスト方法又は高効率の酸洗方法が特開昭61−3
611号公報に開示されている。しかし、近年、酸洗工
程のスピードアップ、酸洗液使用量の低減等が要請され
てきており、さらに13Cr系ステンレス鋼管の黒皮ス
ケールまま出荷も検討されてきている。
If this scale is partially peeled off, it will be indented by the rolling rolls during hot rolling, so descaling with high pressure water or the like is usually carried out before each rolling step. Further, the scale produced by the quenching treatment and the tempering treatment is removed by the above-mentioned shots and pickling, but the pickling is necessary for a long time because the adhesion to the metal is strong. Therefore, a high-efficiency shot blasting method or a high-efficiency pickling method is disclosed in JP-A-61-3.
It is disclosed in Japanese Patent No. 611. However, in recent years, there has been a demand for speeding up of the pickling process, reduction of the amount of pickling solution used, and the like, and shipment of 13Cr stainless steel pipes in black scale is being considered.

【0006】この黒皮ままで出荷される13Cr系ステ
ンレス鋼管は、つぎの諸点において酸洗によってスケー
ルを除去されたものと比較して劣っている。
The 13Cr stainless steel pipe shipped as a black skin is inferior to the one from which scale has been removed by pickling in the following points.

【0007】スケール表面の凹凸大のため出荷時の超
音波探傷による表面傷の判別が困難。
It is difficult to distinguish surface flaws by ultrasonic flaw detection at the time of shipment because of large irregularities on the scale surface.

【0008】スケールの割れ欠落部における地金での
発錆。
Rust on the bare metal in the crack-missing portion of the scale.

【0009】アマニ油等の防錆油の均一塗布が困難と
なることに起因する保管時の発錆。
Rusting during storage due to difficulty in uniformly applying rust preventive oil such as linseed oil.

【0010】曲げ加工時のスケール剥離。Scale peeling during bending.

【0011】外観すなわち見栄えの悪さ。Appearance, that is, poor appearance.

【0012】国際競争力強化のため、近年、需要者から
のこれらの問題に対する解決の要望はますます強くなっ
ている。
In order to strengthen international competitiveness, demands for solutions to these problems from consumers have been increasing in recent years.

【0013】スケールを制御する方法としては、13C
r系ステンレス鋼板に対して特開昭57−19329号
公報に、焼入れ処理前に表面のスケールを除去する方法
が開示されているが、スケール除去に酸洗処理を使用す
るため、連続的に製造される鋼管への適用が困難であ
る。
As a method of controlling the scale, 13C
Japanese Patent Application Laid-Open No. 57-19329 discloses a method for removing scale on the surface of an r-based stainless steel sheet before quenching treatment. However, since the pickling treatment is used for scale removal, continuous production is performed. It is difficult to apply to steel pipes.

【0014】これまでのところ、13Cr系ステンレス
鋼管の熱間圧延中におけるスケール制御を目的とした加
熱圧延条件の最適化の検討はほとんどなされていないの
が実状である。
Up to now, most of the studies have not been made on the optimization of heating and rolling conditions for the purpose of scale control during hot rolling of 13Cr type stainless steel pipes.

【0015】[0015]

【発明が解決しようとする課題】本発明の目的は、耐食
性と表面粗さに優れた酸化層を有する、13Cr系ステ
ンレス鋼からなる継目無鋼管の製造方法を提供すること
にある。
SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for producing a seamless steel pipe made of 13Cr type stainless steel having an oxide layer excellent in corrosion resistance and surface roughness.

【0016】[0016]

【課題を解決するための手段】本発明者らは、上記の目
的を達成すべく鋭意研究を重ねた結果、スケールの構造
及び性状等に関してつぎの知見を得ることができた。
Means for Solving the Problems As a result of intensive studies to achieve the above-mentioned object, the present inventors were able to obtain the following knowledge regarding the structure and properties of the scale.

【0017】(a)13Cr系ステンレス鋼管の表面に
は、スケール外層にポーラスで密着性の悪いFe23
びFe34が、また、スケール内層に緻密で密着力の優
れた(Fe,Cr)−O系のスピネルスケールが形成さ
れる。さらにこのスピネルスケールには耐食性を高める
Crが濃化していることから耐食性にも優れている。
(A) On the surface of the 13Cr stainless steel pipe, Fe 2 O 3 and Fe 3 O 4 are porous and have poor adhesion to the outer layer of the scale, and are dense and have excellent adhesion (Fe, A Cr) -O system spinel scale is formed. Further, this spinel scale is also excellent in corrosion resistance because Cr, which enhances corrosion resistance, is concentrated.

【0018】(b)最終製品における鋼管外面のスケー
ルの凹凸は、外層スケールが地金に強固に密着している
スケール内層から外層/内層界面において部分的に剥離
脱落することにより生じる。従って、外層のFe−O系
のスケールを均一に除去することができれば、緻密な耐
食性に優れたスケールが得られる。
(B) The unevenness of the scale on the outer surface of the steel pipe in the final product is caused when the outer layer scale is partially peeled off from the inner layer of the scale firmly adhered to the base metal at the outer layer / inner layer interface. Therefore, if the Fe—O-based scale of the outer layer can be removed uniformly, a dense scale excellent in corrosion resistance can be obtained.

【0019】(c)そこで、外層のFe−O系のスケー
ルの除去法を詳細に検討した結果、全スケール厚さが1
00μm以上であれば、加熱後高圧水で急激に冷却する
とFe−O系のスケールが急激に収縮し、熱歪みにより
外層スケール/内層スケール界面より外層スケールが均
一に剥離することが明らかとなった。
(C) Then, as a result of detailed examination of the method for removing the Fe—O-based scale of the outer layer, the total scale thickness is 1
When it was at least 00 μm, it was revealed that the Fe-O scale rapidly contracted when heated and rapidly cooled with high-pressure water, and the outer scale was uniformly exfoliated from the outer scale / inner scale interface due to thermal strain. .

【0020】(d)通常の焼入れ処理前の加熱は、重油
燃焼炉中で、900℃〜980℃の温度域で、1時間程
度行われるのが普通である。この条件では約50μm程
度しかスケールが形成されないため、高圧水のみでは外
層のFe−O系のスケールが均一に剥離せず残存するこ
とが明らかとなった。
(D) Usually, heating before quenching is performed in a heavy oil combustion furnace in a temperature range of 900 ° C. to 980 ° C. for about 1 hour. Under these conditions, only about 50 μm of scale was formed, so it was found that the Fe—O-based scale of the outer layer did not uniformly exfoliate and remained only with high-pressure water.

【0021】(e)焼入れ処理前の加熱中に生成するス
ケールを厚くする方法としては、焼入れ温度の上昇、又
は加熱時間の延長がある。しかし、温度の上昇は加熱炉
の寿命の確保の点から、また、時間の延長は効率の低下
によるコスト上昇の点から適用は困難である。
(E) As a method for thickening the scale formed during heating before the quenching treatment, there is an increase in the quenching temperature or an extension of the heating time. However, it is difficult to apply the temperature increase from the viewpoint of ensuring the life of the heating furnace, and the time extension from the viewpoint of cost increase due to decrease in efficiency.

【0022】(f)そこでスケール成長に及ぼす加熱雰
囲気の影響を詳細に調査した結果、雰囲気中の水蒸気濃
度を15体積%以上とすることにより、スケールの成長
が著しく加速され、焼入れ前の通常の加熱時間内に10
0μm以上のスケールが形成されることを見いだした。
さらに、酸素を5体積%以上含ませた雰囲気においても
スケールの成長速度が増加することを見いだした。
(F) Then, as a result of detailed investigation of the influence of the heating atmosphere on the scale growth, the growth of the scale was remarkably accelerated by setting the water vapor concentration in the atmosphere to 15% by volume or more, and the usual scale before quenching was used. 10 within heating time
It was found that a scale of 0 μm or more was formed.
Further, it was found that the growth rate of scale increased even in an atmosphere containing oxygen in an amount of 5% by volume or more.

【0023】本発明は上記の事項を組み合わせて完成さ
れたもので、次の13Cr系ステンレス鋼管の加熱条件
及び冷却条件を含む製造方法を要旨とする。
The present invention has been completed by combining the above items, and its gist is a manufacturing method including the following heating and cooling conditions for a 13Cr stainless steel pipe.

【0024】(1) 圧延終了後、熱処理前の13Cr系
ステンレス鋼管を加熱し、全スケール厚さが100μm
以上の内層と外層からなるスケールを形成させた後、高
圧水で冷却することによりスケール外層を除去する耐食
性と表面粗さに優れた酸化層を有する13Cr系ステン
レス鋼管の製造方法([発明1]とする)。
(1) After rolling, the 13Cr stainless steel pipe before heat treatment is heated so that the total scale thickness is 100 μm.
After forming a scale consisting of the above inner layer and outer layer, the scale outer layer is removed by cooling with high-pressure water to produce a 13Cr-based stainless steel pipe having an oxide layer excellent in corrosion resistance and surface roughness ([Invention 1]. And).

【0025】(2) 圧延終了後、熱処理前の13Cr系
ステンレス鋼管を15体積%以上の水蒸気、又は5体積
%以上の酸素を含む雰囲気中で加熱し、全スケール厚さ
が100μm以上の内層と外層からなるスケールを形成
させた後、高圧水で冷却することによりスケール外層を
除去する耐食性と表面粗さに優れた酸化層を有する13
Cr系ステンレス鋼管の製造方法([発明2]とす
る)。
(2) After rolling, the 13Cr stainless steel pipe before heat treatment is heated in an atmosphere containing 15 vol% or more steam or 5 vol% or more oxygen to form an inner layer having a total scale thickness of 100 μm or more. After forming a scale consisting of an outer layer, the scale outer layer is removed by cooling with high-pressure water. The oxide layer has excellent corrosion resistance and surface roughness.
A method for producing a Cr-based stainless steel pipe (referred to as [invention 2]).

【0026】上記〔発明1〕において、13Cr系ステ
ンレス鋼とはマルテンサイト系ステンレス鋼であって、
化学組成として、重量%で、Cr:11〜15%、M
o:0〜0.75%、Ni:0〜3.5%、Pb:0〜
0.3%、C:0.15%以下、Si:1%以下及びM
n:1.25%以下を含む鋼で、例えばJIS規格のS
US403等が該当する。
In the above [Invention 1], the 13Cr stainless steel is a martensitic stainless steel,
As a chemical composition, by weight%, Cr: 11 to 15%, M
o: 0 to 0.75%, Ni: 0 to 3.5%, Pb: 0
0.3%, C: 0.15% or less, Si: 1% or less and M
n: Steel containing 1.25% or less, for example, JIS standard S
For example, US403 is applicable.

【0027】また、“加熱し、全スケール厚さ100μ
m以上のスケールを形成させる”のは、焼入れ前の加熱
のときである。すなわち、直接焼入れの場合は、仕上げ
圧延後の補熱のときであり、再加熱焼入れの場合は連続
式加熱炉で加熱するときである。
In addition, "heating, the total scale thickness 100μ
The formation of a scale of m or more "is performed during heating before quenching. That is, in the case of direct quenching, it is during supplementary heat after finish rolling, and in the case of reheating quenching, it is in a continuous heating furnace. It's time to heat.

【0028】“全スケール厚さ”は、スケール外層とス
ケール内層からなるスケール全体の厚さをさす。“耐食
性と表面粗さに優れた酸化層”は、スピネルスケール等
を主成分とするスケール内層からなる密着性に優れたス
ケールの部分をさす。
"Total scale thickness" refers to the total thickness of the scale consisting of the outer scale layer and the inner scale layer. "Oxidized layer with excellent corrosion resistance and surface roughness" refers to the part of the scale with excellent adhesion consisting of the inner layer of the scale containing spinel scale as the main component.

【0029】“高圧水での冷却”は、スケール外層を除
去するための冷却をさし、焼入れのための冷却とは別の
ものである。本発明の対象とする13Cr鋼の場合、焼
入れはエアークェンチにより行われる。
"Cooling with high pressure water" refers to cooling for removing the outer scale layer and is different from cooling for quenching. In the case of the 13Cr steel which is the object of the present invention, quenching is performed by air quench.

【0030】〔発明2〕において限定する雰囲気の一つ
は、水蒸気15体積%以上の他に酸素、窒素、炭酸ガス
を含むことができ、また、他の一つは、酸素5体積%以
上の他に水蒸気、窒素、炭酸ガスを含んでもよい。
One of the atmospheres defined in [Invention 2] can contain oxygen, nitrogen and carbon dioxide gas in addition to water vapor of not less than 15% by volume, and the other atmosphere of not less than 5% by volume of oxygen. In addition, it may contain water vapor, nitrogen, carbon dioxide gas.

【0031】[0031]

【発明の実施の態様】DETAILED DESCRIPTION OF THE INVENTION

1.全スケール厚さ 全スケール厚さが100μm以下であれば、スケール外
層の均一な剥離が悪化し高圧水で水冷しても部分的に外
層スケールが残存し、表面粗さが増大するので、全スケ
ール厚さは100μm以上とする。一方、全スケール厚
さが500μmを超えるとスピネルスケール等のスケー
ル内層の密着性が劣化するので、500μm以下とする
ことが望ましい。良好な密着性を確保したうえで、脱ス
ケールもより完全なものとするには、100〜300μ
mとするのが望ましい。
1. Total scale thickness If the total scale thickness is 100 μm or less, uniform peeling of the outer layer of the scale deteriorates and the outer layer scale partially remains even if water-cooled with high-pressure water, increasing the surface roughness. The thickness is 100 μm or more. On the other hand, if the total scale thickness exceeds 500 μm, the adhesion of the inner layer of the scale such as spinel scale deteriorates, so it is desirable that the thickness be 500 μm or less. To ensure good adhesion and complete descaling, 100-300μ
It is desirable to set m.

【0032】つぎに、〔発明2〕は、加熱雰囲気を限定
することにより上記全スケール厚さ100μm以上の確
保を容易にした発明である。
Next, [Invention 2] is an invention which makes it easy to secure the above-mentioned total scale thickness of 100 μm or more by limiting the heating atmosphere.

【0033】2.水蒸気濃度 〔発明2〕における一つの雰囲気は、スケールの成長を
促進させ、〔発明1〕の全スケール厚さ100μmを通
常の焼入れ前の加熱において実現しやすくするために、
水蒸気を15体積%以上雰囲気に含ませるものである。
焼入れ前の加熱炉の水蒸気濃度が15体積%未満ではス
ケールの成長速度が遅く、通常の焼入れ前の加熱時間で
は100μm以上のスケールが形成されないので15体
積%以上とする。
2. One atmosphere at a water vapor concentration [Invention 2] accelerates the growth of the scale, and in order to easily achieve the total scale thickness of 100 [mu] m of [Invention 1] in the normal heating before quenching,
Water vapor is included in the atmosphere in an amount of 15 vol% or more.
If the steam concentration in the heating furnace before quenching is less than 15% by volume, the growth rate of the scale is slow, and the scale of 100 μm or more is not formed in the normal heating time before quenching.

【0034】一方、水蒸気濃度が50体積%を超える
と、加熱炉の損傷を招き炉の寿命を縮めるので、50体
積%以下とすることが望ましい。炉の寿命を確保したう
えでスケールの成長をより一層速めるには、15〜50
体積%とするのが望ましい。
On the other hand, if the water vapor concentration exceeds 50% by volume, the heating furnace is damaged and the life of the furnace is shortened. To secure the life of the furnace and further accelerate the growth of scale, 15 to 50
It is desirable to set the volume%.

【0035】水蒸気以外の他の成分として酸素を含んで
もよいし含まなくてもよい。
Oxygen may or may not be included as a component other than water vapor.

【0036】3.酸素濃度 〔発明2〕のもう一つの雰囲気は、酸素を含ませスケー
ル成長速度を高めるものである。酸素濃度が5体積%未
満ではスケールの成長が十分でなく、水蒸気との共存の
効果が認められないため5体積%以上とする。
3. Another atmosphere having an oxygen concentration [Invention 2] contains oxygen to increase the scale growth rate. If the oxygen concentration is less than 5% by volume, the growth of the scale is not sufficient and the effect of coexistence with water vapor is not recognized, so the amount is made 5% by volume or more.

【0037】一方、酸素濃度が10体積%以上のときに
は炉壁等の損傷が激しくなるので、10体積%以下とす
るのが望ましい。
On the other hand, when the oxygen concentration is 10% by volume or more, damage to the furnace wall and the like becomes severe, so it is desirable to set it to 10% by volume or less.

【0038】このとき、酸素以外に水蒸気を含まなくて
も、また、含んでもよい。
At this time, water vapor may or may not be included other than oxygen.

【0039】[0039]

【実施例】素材ビレットはAPI(American Petroleum
Institute)規格13Cr系ステンレス鋼および13C
r改良鋼を用いた。
[Example] Material billet is API (American Petroleum
Institute) Standard 13Cr stainless steel and 13C
r Improved steel was used.

【0040】表1は供試材の化学成分を示す。鋼符号A
がAPI規格13Cr系ステンレス鋼であり、鋼符号A
Sが改良13Cr系ステンレス鋼である。
Table 1 shows the chemical composition of the test material. Steel code A
Is API standard 13Cr stainless steel, and the steel code A
S is an improved 13Cr type stainless steel.

【0041】[0041]

【表1】 [Table 1]

【0042】素材ビレット(外形192mm)を回転炉
床式加熱炉において1100℃から1200℃の温度域
に加熱し、マンネスマンピアサーによって外形192m
m、肉厚16mm、長さ6650mmの中空素管を製造
し、その後マンドレルミルによって外形151mm、肉
厚6.5mm、長さ20mの仕上げ用素管を製造し、再
加熱炉で1100℃にて20分間加熱後ストレッチレデ
ューサーによって外形63.5mm、肉厚5.5mm、
長さ56mの製品とした。
The material billet (outer diameter 192 mm) is heated in a rotary hearth type heating furnace to a temperature range of 1100 ° C. to 1200 ° C., and an outer diameter 192 m is obtained by a Mannesmann piercer.
m, wall thickness 16 mm, length 6650 mm, and then a mandrel mill is used to manufacture an outer diameter 151 mm, wall thickness 6.5 mm, and length 20 m, and a finishing tube with a reheating furnace at 1100 ° C. After heating for 20 minutes, a stretch reducer gives an outer diameter of 63.5 mm and a wall thickness of 5.5 mm.
It was a product with a length of 56 m.

【0043】表2は、焼入れ処理前の加熱条件及びスケ
ール厚さを示す一覧表である。
Table 2 is a list showing the heating conditions and the scale thickness before the quenching treatment.

【0044】[0044]

【表2】 [Table 2]

【0045】表2に示す条件で加熱後、高圧水により焼
入れ、その後730℃での焼戻し処理を実施し、管外表
面に、通常の方法であるスプレーによりアマニ油を塗布
し最終製品とした。表2に示す加熱雰囲気のH2O及び
2以外の残り組成は、 CO2:11体積%及び残部窒
素である。
After heating under the conditions shown in Table 2, quenching was carried out with high-pressure water, and then tempering treatment was carried out at 730 ° C., and linseed oil was applied to the outer surface of the tube by spraying, which is a usual method, to obtain a final product. The remaining composition other than H 2 O and O 2 in the heating atmosphere shown in Table 2 is CO 2 : 11 vol% and the balance nitrogen.

【0046】最終製品に対して、表面粗さ測定、及び
5重量%の塩化ナトリウムに浸析後、野外に暴露し発錆
するまでの日数により耐食性を評価した。
The final product was evaluated for corrosion resistance by measuring the surface roughness and by immersing it in 5% by weight of sodium chloride and then exposing it to the field and the number of days until rusting.

【0047】結果を上述の表2に示す。本発明例である
試験番号1〜8は、焼入れ前の加熱中に生成する全スケ
ール厚さが100μm以上あるために高圧水による冷却
で外層スケールが均一に剥離し表面粗さが良好になり、
上記した発錆防止油(アマニ油)が均一に塗布されてい
るため発錆が生じない。
The results are shown in Table 2 above. Test Nos. 1 to 8, which are examples of the present invention, have a total scale thickness of 100 μm or more generated during heating before quenching, so that outer layer scale is uniformly peeled off by cooling with high-pressure water to improve surface roughness,
Since the above-mentioned rust preventive oil (linseed oil) is uniformly applied, rust does not occur.

【0048】一方、従来の方法では、焼入れ前の加熱中
に形成される全スケール厚さが100μm未満であるた
め、高圧水で冷却しても表面の粗さが悪く発錆防止油塗
布後数日で錆が発生した。
On the other hand, in the conventional method, since the total scale thickness formed during heating before quenching is less than 100 μm, the surface roughness is poor even when cooled with high-pressure water, and the number of rust-preventive oils applied is less than several. Rust occurred in the day.

【0049】[0049]

【発明の効果】本発明により、13Cr系ステンレス鋼
からなる、耐食性と表面粗さに優れた酸化層を有する継
目無鋼管の製造方法を提供でき、黒皮ままで同鋼管を供
給できることになり、関連産業に非常に有益である。
According to the present invention, it is possible to provide a method for producing a seamless steel pipe having an oxidation layer excellent in corrosion resistance and surface roughness, which is made of 13Cr type stainless steel, and the steel pipe can be supplied as a black skin. Very beneficial to related industries.

───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平5−269507(JP,A) (58)調査した分野(Int.Cl.7,DB名) C21D 9/00 - 9/44 C21D 9/50 C21D 1/02 - 1/84 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-5-269507 (JP, A) (58) Fields investigated (Int.Cl. 7 , DB name) C21D 9/00-9/44 C21D 9 / 50 C21D 1/02-1/84

Claims (2)

(57)【特許請求の範囲】(57) [Claims] 【請求項1】圧延終了後、熱処理前の13Cr系ステン
レス鋼管を加熱し、全スケール厚さが100μm以上の
内層と外層からなるスケールを形成させた後、高圧水で
冷却することによりスケール外層を除去することを特徴
とする耐食性と表面粗さに優れた酸化層を有する13C
r系ステンレス鋼管の製造方法。
1. After completion of rolling, the 13Cr stainless steel pipe before heat treatment is heated to form a scale consisting of an inner layer and an outer layer having a total scale thickness of 100 μm or more, and then cooled with high-pressure water to form a scale outer layer. 13C having an oxide layer excellent in corrosion resistance and surface roughness characterized by being removed
Method for producing r-type stainless steel pipe.
【請求項2】圧延終了後、熱処理前の13Cr系ステン
レス鋼管を15体積%以上の水蒸気、又は5体積%以上
の酸素を含む雰囲気中で加熱し、全スケール厚さが10
0μm以上の内層と外層からなるスケールを形成させた
後、高圧水で冷却することによりスケール外層を除去す
ることを特徴とする耐食性と表面粗さに優れた酸化層を
有する13Cr系ステンレス鋼管の製造方法。
2. After completion of rolling, the 13Cr stainless steel pipe before heat treatment is heated in an atmosphere containing 15% by volume or more of steam or 5% by volume or more of oxygen to give a total scale thickness of 10
Manufacture of a 13Cr stainless steel pipe having an oxide layer excellent in corrosion resistance and surface roughness, which comprises removing a scale outer layer by cooling with high pressure water after forming a scale consisting of an inner layer and an outer layer of 0 μm or more Method.
JP22246396A 1996-08-23 1996-08-23 Method for producing 13Cr stainless steel tube having oxide layer Expired - Fee Related JP3379345B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP22246396A JP3379345B2 (en) 1996-08-23 1996-08-23 Method for producing 13Cr stainless steel tube having oxide layer

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP22246396A JP3379345B2 (en) 1996-08-23 1996-08-23 Method for producing 13Cr stainless steel tube having oxide layer

Publications (2)

Publication Number Publication Date
JPH1060538A JPH1060538A (en) 1998-03-03
JP3379345B2 true JP3379345B2 (en) 2003-02-24

Family

ID=16782819

Family Applications (1)

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Country Status (1)

Country Link
JP (1) JP3379345B2 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2001026818A (en) * 1999-07-12 2001-01-30 Kawasaki Steel Corp Method and apparatus for continuously annealing stainless steel sheet
JP4116383B2 (en) * 2002-09-25 2008-07-09 住友電工スチールワイヤー株式会社 Oil temper wire for valve spring or spring and manufacturing method thereof
EP1683884B1 (en) 2003-10-10 2017-06-28 Nippon Steel & Sumitomo Metal Corporation Martensitic stainless steel pipe and method for production thereof
EP1637785B9 (en) 2004-09-15 2011-01-05 Sumitomo Metal Industries, Ltd. Steel tube excellent in exfoliation resistance of scale on inner surface
JP5270864B2 (en) * 2007-06-13 2013-08-21 高周波熱錬株式会社 Spring steel wire manufacturing method and manufacturing apparatus
MX2016012348A (en) 2014-05-16 2017-01-23 Nippon Steel & Sumitomo Metal Corp Seamless steel pipe for line pipe, and method for producing same.
MX2016015099A (en) * 2014-05-21 2017-02-22 Jfe Steel Corp High-strength stainless steel seamless pipe for oil well, and method for producing same.
JP7323784B2 (en) * 2019-07-24 2023-08-09 日本製鉄株式会社 Manufacturing method of stainless steel pipe
JP7277751B2 (en) * 2019-07-24 2023-05-19 日本製鉄株式会社 Manufacturing method of stainless steel pipe

Also Published As

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