JPH02255204A - Plug for piercing and rolling for production of steel pipe - Google Patents
Plug for piercing and rolling for production of steel pipeInfo
- Publication number
- JPH02255204A JPH02255204A JP7899289A JP7899289A JPH02255204A JP H02255204 A JPH02255204 A JP H02255204A JP 7899289 A JP7899289 A JP 7899289A JP 7899289 A JP7899289 A JP 7899289A JP H02255204 A JPH02255204 A JP H02255204A
- Authority
- JP
- Japan
- Prior art keywords
- plug
- steel
- rolling
- steel pipe
- drilling
- 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.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 30
- 239000010959 steel Substances 0.000 title claims abstract description 30
- 238000005096 rolling process Methods 0.000 title claims abstract description 13
- 238000004519 manufacturing process Methods 0.000 title claims description 10
- 229910052804 chromium Inorganic materials 0.000 claims abstract description 3
- 239000012535 impurity Substances 0.000 claims abstract description 3
- 229910052748 manganese Inorganic materials 0.000 claims abstract description 3
- 229910052759 nickel Inorganic materials 0.000 claims abstract description 3
- 229910052758 niobium Inorganic materials 0.000 claims abstract description 3
- 238000005553 drilling Methods 0.000 claims description 15
- 229910052799 carbon Inorganic materials 0.000 abstract description 2
- 230000002035 prolonged effect Effects 0.000 abstract 1
- 239000000463 material Substances 0.000 description 12
- 229910000851 Alloy steel Inorganic materials 0.000 description 7
- 230000000694 effects Effects 0.000 description 6
- 229910000975 Carbon steel Inorganic materials 0.000 description 5
- 239000010962 carbon steel Substances 0.000 description 5
- 238000005275 alloying Methods 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000004080 punching Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910001208 Crucible steel Inorganic materials 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 238000011835 investigation Methods 0.000 description 1
- 229910052742 iron Inorganic materials 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
- 239000000203 mixture Substances 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 238000009877 rendering Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B25/00—Mandrels for metal tube rolling mills, e.g. mandrels of the types used in the methods covered by group B21B17/00; Accessories or auxiliary means therefor ; Construction of, or alloys for, mandrels or plugs
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
この発明は継目無鋼管の製造に用いられる穿孔及び圧延
用プラグ、とくに高合金鋼鋼管を製造する場合に耐久性
を存し、かつ内面性状のすぐれた鋼管を製造できる鋼管
製造用穿孔及び圧延用プラグに関する。Detailed Description of the Invention (Field of Industrial Application) The present invention provides a drilling and rolling plug used in the production of seamless steel pipes, particularly in the production of high alloy steel pipes, which has durability and improved inner surface properties. The present invention relates to a drilling and rolling plug for manufacturing steel pipes that can produce excellent steel pipes.
（従来の技術）
継目無鋼管の製造方法のひとつに、マンネスマン穿孔機
により素管を製造し、この素管を傾斜圧延機で延伸圧延
する方法がある。(Prior Art) One of the methods for manufacturing seamless steel pipes is a method in which a blank tube is manufactured using a Mannesmann drilling machine, and the blank tube is stretched and rolled using an inclined rolling mill.
マンネスマン穿孔機は第１図に示すように、互いに反対
方向に傾斜して配置されて同一方向に回転するロール１
ａとｌｂ、このロールの後方に配置されたマンドレル２
、及びそれに支持されたプラグ３から構成されている。As shown in Fig. 1, the Mannesmann drilling machine has rolls 1 arranged at inclinations in opposite directions and rotating in the same direction.
a and lb, mandrel 2 placed behind this roll
, and a plug 3 supported by it.
この穿孔機により素管を製造するには、ビレット４をロ
ールｌａと１ｂの間に送り込む、ビレット４はロールに
より回転鍛造されてその中心部に割れが形成されると共
に後方のプラグ３に押し込まれて素管５となる。このあ
と素管５は傾斜圧延機（穿孔機と同じ構造を有す）によ
り延伸圧延されて継目無鋼管になる。In order to manufacture a raw pipe using this punching machine, a billet 4 is fed between rolls la and 1b, the billet 4 is rotary forged by the rolls, a crack is formed in its center, and the billet 4 is pushed into the plug 3 at the rear. It becomes the raw tube 5. Thereafter, the raw pipe 5 is elongated and rolled by an inclined rolling mill (having the same structure as a punching machine) to become a seamless steel pipe.
ところで鋼管穿孔機および傾斜圧延機用のプラグとして
、従来はプラグ表面に酸化スケールを形成させた３ Ｃ
ｒ −Ｉ Ｎ！ｔｌｔｉ製プラグが多く用いられてきた
。鋼管材料が炭素鋼の場合にはこのプラグでも２００バ
ス以上の使用に耐える。しかし鋼管材料が高合金化する
につれてその寿命は著しく短くなる。たとえば１３ Ｃ
ｒｉｍｌのビレットを穿孔する場合には３〜４パス程度
で、１８Ｃｒ−８Ｎｉ鋼のときにはわずか１パスでプラ
グ先端部や胴体部に溶損（えぐれ）が生じて使用できな
くなる。By the way, as plugs for steel pipe boring machines and inclined rolling mills, 3C was conventionally used with oxide scale formed on the plug surface.
r-IN! TLTI plugs have been widely used. If the steel pipe material is carbon steel, this plug can withstand use for more than 200 buses. However, as the steel pipe material becomes highly alloyed, its life becomes significantly shorter. For example, 13C
When drilling a rim billet, it takes about 3 to 4 passes, and when drilling a hole in 18Cr-8Ni steel, it takes just one pass to cause melt damage (gouge) to the tip and body of the plug, rendering it unusable.
そこで高合金鋼鋼管用プラグとして、３Ｃｒ−ＩＮｉ系
鋳鋼にＭｏなどの合金元素を含有させて高温強度を高め
たプラグが提案された（特開昭５５−１１０７６２号公
報）。しかしこのプラグでも上記問題は完全に解決され
ていない。Therefore, as a plug for high-alloy steel pipes, a plug was proposed in which alloying elements such as Mo were added to 3Cr-INi cast steel to increase high-temperature strength (Japanese Patent Application Laid-Open No. 110762/1983). However, this plug does not completely solve the above problem.
（発明が解決しようとする課題）
この発明の目的は、継目無鋼管、とくに高合金鋼の継目
無鋼管を製造する場合に生じるプラグ溶損の問題を解決
し、その寿命を大幅に延長できる継目無鋼管製造用の穿
孔及び圧延用プラグを提供することにある。(Problems to be Solved by the Invention) The purpose of the present invention is to solve the problem of plug melting that occurs when manufacturing seamless steel pipes, especially seamless steel pipes made of high alloy steel, and to create a seam that can significantly extend the life of the seamless steel pipe. An object of the present invention is to provide a drilling and rolling plug for producing steelless pipes.
（課題を解決するための手段）
本発明者は、高合金鋼継目無鋼管の製造に用いられるプ
ラグの寿命延長について種々検討を重ねるうち、高合金
鋼材料を穿孔及び圧延する際にプラグ溶損（えぐれ）を
起こすのは管素材の変形抵抗が高いことにもよるが、そ
のとき発生するｗＳ熱が大きな原因を占めているのでは
ないかとの考えをいだき、以下に述べる摩擦試験を行っ
た。(Means for Solving the Problems) While conducting various studies on extending the life of plugs used in the manufacture of seamless high-alloy steel pipes, the present inventor discovered that plugs melt when drilling and rolling high-alloy steel materials. Although the cause of this (gouging) is due to the high deformation resistance of the pipe material, we thought that the wS heat generated at that time may be a major cause, so we conducted the friction test described below. .
すなわち、９５０°Ｃに３時間加熱して表面にスケール
被膜を形成させたプラグ材試験片（ｌｈｍ角、２０ＩＩ
ＩＩＩ厚さの３Ｃｒ−ＩＮ＋鋼材）を、高周波誘導加熱
により１，２００°Ｃに加熱保持されて５０ｒｐｍで回
転する外径１００ｍ−の円筒状鋼管材試験片（炭素鋼、
１３Ｃｒ鋼、１８Ｃｒ−８Ｎｉ鋼の３種類）の外周面に
５０Ｋｇｆ／ａｍ”の力で押しつけ、そのときの摩擦係
数を調べた。その結果、鋼管材料が炭素鋼のときの摩擦
係数・は０．１以下であるが、１３Ｃｒ鋼や１８ Ｃｒ
−８Ｎｉｌ１４のような高合金鋼材の場合にはその摩
擦係数は０．５〜０．６と極めて高いことをつきとめた
。That is, a plug material test piece (lhm square, 20II
A cylindrical steel pipe specimen (carbon steel,
It was pressed against the outer circumferential surface of three types of steel (13Cr steel and 18Cr-8Ni steel) with a force of 50 kgf/am'', and the friction coefficient at that time was investigated.As a result, when the steel pipe material was carbon steel, the friction coefficient was 0. 1 or less, but 13Cr steel and 18Cr
It has been found that high alloy steel such as -8Nil14 has an extremely high friction coefficient of 0.5 to 0.6.
炭素鋼に較べて１３ ＣｒｔＲや１８Ｃｒ ８ Ｎ１
ｊｉｌの摩擦係数が著しく高いのは、これらの鋼は変形
抵抗が高いうえにスケールがつき難く、摩擦時にプラグ
材のスケール被膜が容易に剥離して金属同士が直接接触
するためであると考えられる。Compared to carbon steel, 13 CrtR and 18Cr 8 N1
It is thought that the reason why the friction coefficient of JIL is extremely high is that these steels have high deformation resistance and are difficult to scale, and the scale film of the plug material easily peels off during friction, causing direct contact between the metals. .
そこで摩擦係数を低下させるための手段を更に検討した
結果、従来のプラグ材料に新たな合金元素を含有させる
のが最も適切であろうと判断し、プラグ材料である３Ｃ
ｒ−ＩＮｉ綱に種々の合金元素を含有させた。そしてそ
れらのプラグを用いて摩擦試験を行った。その結果、プ
ラグ材料に含有させる合金元素としてはＮｂが最も適し
ており、その含有量は第２図に示すように２％を越え８
重量％までの範囲がよいということを知った。As a result of further investigation into ways to reduce the coefficient of friction, we determined that it would be most appropriate to incorporate a new alloy element into the conventional plug material.
The r-INi steel was made to contain various alloying elements. Friction tests were then conducted using these plugs. As a result, Nb is the most suitable alloying element to be included in the plug material, and its content exceeds 2% as shown in Figure 2.
I learned that a range up to % by weight is good.
この発明は上記の知見にもとづいてなされたものであり
、その要旨はつぎのとおりである。This invention was made based on the above findings, and the gist thereof is as follows.
重量％で、 Ｃ：０．１〜０．５％
Ｓｉ：０．２〜２．０％
Ｍｎ： ０．２〜２．０％
Ｃｒ： １．０〜６．０％
Ｎｉ：１．０〜６．０％
Ｎｂ： ２．０を越え８．０％以下
を含み、残部がＦｅ及び不可避的不純物からなり、表面
にスケール被膜が形成されている鋼管製造用穿孔および
圧延用プラグ、である。In weight%, C: 0.1-0.5% Si: 0.2-2.0% Mn: 0.2-2.0% Cr: 1.0-6.0% Ni: 1.0- 6.0% Nb: This is a plug for drilling and rolling for manufacturing steel pipes, containing more than 2.0% and less than 8.0%, with the remainder consisting of Fe and unavoidable impurities, and a scale film is formed on the surface.
（作用）
まず本発明のプラグの化学成分を限定する理由を説明す
る。(Function) First, the reason for limiting the chemical components of the plug of the present invention will be explained.
Ｃ：Ｃが０．１％未満では強度が不足し、０．５％を越
えると靭性が低下して熱亀裂が発生するので、その範囲
は０．１〜０．５％とする。C: If the C content is less than 0.1%, the strength will be insufficient, and if it exceeds 0.5%, the toughness will decrease and thermal cracks will occur, so the range should be 0.1 to 0.5%.
Ｓｉ：Ｓｉは脱酸調整と鋳造性をよくするために０．２
％以上にする必要がある。しかし２．０％を越えると靭
性を損なうため、０．２〜２．０％の範囲にする。Si: Si is 0.2 to improve deoxidation adjustment and castability.
% or more. However, if it exceeds 2.0%, toughness will be impaired, so it should be in the range of 0.2 to 2.0%.
Ｍｎ：Ｍｎは脱酸剤としてまた熱間加工性を向上させる
ために０．２％以上含有させる必要があるが、２．０％
を越えて含有させてもその効果は変わらないので、０．
２〜２．０％とする。Mn: Mn must be contained in an amount of 0.2% or more in order to act as a deoxidizing agent and improve hot workability, but 2.0%
The effect remains the same even if the content exceeds 0.
2 to 2.0%.
Ｃｒ：Ｃｒは高温強度を高め、かつ密着性のよいスケー
ル層を形成させるためには１．０％以上にする必要があ
る。しかし６．０％を越えると逆にスケールの密着性が
悪くなるので、１．０〜６．０％の範囲にする。Cr: Cr needs to be 1.0% or more in order to increase high temperature strength and form a scale layer with good adhesion. However, if it exceeds 6.0%, the adhesion of the scale will deteriorate, so it should be in the range of 1.0 to 6.0%.
Ｎｉ： Ｎｉは靭性の向上と密着性をよくするために１
．０％以上含有させるが、６．０％を越えて含有させて
もその効果は変化しないので１，０〜６．０％の範囲に
する。Ni: Ni is added to improve toughness and adhesion.
．． The content should be 0% or more, but the effect will not change even if the content exceeds 6.0%, so the content should be in the range of 1.0 to 6.0%.
Ｎｂ：Ｎｂは本発明のプラグを構成する重要な元素であ
り、高温強度を高める効果があるうえ母材とスケール間
の粒界酸化を助長してスケールの耐剥離性を高める。さ
らにスケール層中に存在して穿孔時に高温管材と接触す
る際に、Ｆｅ酸化物との間で比較的低融点の共晶化合物
を形成して摩擦係数を下げる働きをする。第２図に示す
ようにその含有量が２．０％以下ではその効果が少ない
、−方、８．０％を越えて含有させるとかえって靭性を
低下させるので、その範囲は０．２％を越え８．０％以
下にする。Nb: Nb is an important element constituting the plug of the present invention, and has the effect of increasing high-temperature strength, and also promotes grain boundary oxidation between the base material and scale, thereby increasing the peeling resistance of the scale. Furthermore, it exists in the scale layer and when it comes into contact with the high-temperature pipe material during drilling, it forms a relatively low melting point eutectic compound with Fe oxide, which serves to lower the coefficient of friction. As shown in Figure 2, if the content is less than 2.0%, the effect is small, but if the content exceeds 8.0%, the toughness is reduced, so the range is 0.2% or less. Over 8.0% or less.
また本発明のプラグに形成するスケール層の厚さは３０
〜２００μ論が好ましい、３０μ論未満では摩擦係数を
下げる効果が少なく、２００μｍ越えるとスケールの密
着性がかえって低下するからである。なおプラグ表面に
スケールを形成させる方法はとくに限定しないが、たと
えば酸化雰囲気中で８００〜１．２００℃程度の温度に
加熱保持することによって比較的簡単に形成させること
ができる。Further, the thickness of the scale layer formed on the plug of the present invention is 30
A thickness of ~200 μm is preferable, because if it is less than 30 μm, there is little effect of lowering the friction coefficient, and if it exceeds 200 μm, the adhesion of the scale will actually decrease. Note that the method for forming scale on the plug surface is not particularly limited, but it can be formed relatively easily, for example, by heating and maintaining the scale at a temperature of about 800 to 1.200° C. in an oxidizing atmosphere.
（実施例）
以下、実施例にもとづいて説明する。第１表に示す化学
成分を有し、熱処理（９５０°Ｃで３時間保持）によっ
て表面に厚さ約１００μ曽のスケールを形成させた直径
５０ｍ■のプラグを用い、１８Ｃｒ−８Ｎｉ綱の丸ビレ
ット（直径６０■―）を穿孔して外径６２Ｉ１ｍｌ、内
径５３ｍ５＋、長さ１．２ｍの素管を製造した。(Example) Hereinafter, it will be explained based on an example. A round billet of 18Cr-8Ni steel was made using a plug with a diameter of 50 m, which had the chemical components shown in Table 1 and had a scale of about 100 μm in thickness formed on its surface by heat treatment (held at 950°C for 3 hours). (diameter 60mm) was bored to produce a blank pipe with an outer diameter of 62I 1ml, an inner diameter of 53m5+, and a length of 1.2m.
そしてプラグに溶損またはクラックが生じて使用できな
くなるまでの穿孔本数を調べた。また本発明のプラグ（
第１表の本発明例１〜９）の性能を明確にするために、
本発明が規定する範囲から外れた成分のプラグ（同表の
比較例１０〜１５）、及びＮｂを全く含まないプラグ（
同表の従来例１６）により上記と同じ成分のビレットを
穿孔して素管を製造してその寿命を調べた。The number of holes to be drilled before the plug became unusable due to melting damage or cracks was determined. In addition, the plug of the present invention (
In order to clarify the performance of the invention examples 1 to 9) in Table 1,
Plugs with components outside the range specified by the present invention (Comparative Examples 10 to 15 in the same table), and plugs containing no Nb at all (Comparative Examples 10 to 15 in the same table)
According to Conventional Example 16) in the same table, a billet having the same composition as above was perforated to produce a blank pipe, and its lifespan was investigated.
その結果を第１表のプラグ寿命の欄に示す、これから明
らかなように、本発明のプラグを使用した場合には少な
くとも３本のビレットを穿孔できた。これに対し、比較
例および従来例のプラグではわずか１本の穿孔でその寿
命が尽きた。The results are shown in the plug life column of Table 1. As is clear from the results, at least three billets could be punched when the plug of the present invention was used. On the other hand, the plugs of the comparative example and the conventional example reached the end of their life after only one puncture.
この実施例は１８Ｃｒ−８Ｎｉ鋼を穿孔する場合を述べ
たが、それより合金元素含有量のすくない９Ｃｒ鋼や１
３Ｃｒ鋼、或いは炭素鋼などの場合にはその寿命は一層
長くなる。また本発明のプラグは穿孔用以外にも圧延用
などにも使用できることはいうまでもない。This example describes the case of drilling 18Cr-8Ni steel, but 9Cr steel and 18Cr steel, which have a lower alloying element content,
In the case of 3Cr steel or carbon steel, the life is even longer. It goes without saying that the plug of the present invention can be used not only for drilling but also for rolling.
（以下、余白）
第１表
（以下、余白）
（発明の効果）
以上に説明したように、本発明のプラグはすぐれた耐久
性と潤滑性を有する。したがって高合金鋼鋼管材の穿孔
および圧延に使用しても寿命が長く、生産性を著しく向
上させることができる。そして潤滑性がよいために製品
鋼管の内面性状もきわめて良好である。(Hereinafter, blank space) Table 1 (Hereinafter, blank space) (Effects of the invention) As explained above, the plug of the present invention has excellent durability and lubricity. Therefore, even when used for drilling and rolling high-alloy steel pipe materials, it has a long life and can significantly improve productivity. Furthermore, due to the good lubricity, the inner surface properties of the product steel pipes are also extremely good.
第１図は、マンネスマン穿孔機によりビレットを穿孔す
る状態を示す図、
第２図は、プラグのＮｂ含有量と摩擦係数との関係を示
す図、
である。
１ａおよびｌｂはロール、２はマンドレル、３はプラグ
、４はビレット、５は素管。FIG. 1 is a diagram showing the state in which a billet is perforated by a Mannesmann drilling machine, and FIG. 2 is a diagram showing the relationship between the Nb content of the plug and the coefficient of friction. 1a and lb are rolls, 2 is a mandrel, 3 is a plug, 4 is a billet, and 5 is a raw tube.
Claims (1)
面に酸化スケール被膜が形成されていることを特徴とす
る鋼管製造用穿孔および圧延用プラグ。[Claims] In weight percent, C: 0.1-0.5% Si: 0.2-2.0% Mn: 0.2-2.0% Cr: 1.0-6.0% Ni: 1.0 to 6.0% Nb: Contains more than 2.0 and less than 8.0%, the balance is Fe and inevitable impurities, and an oxide scale film is formed on the surface. Plugs for drilling and rolling for steel pipe manufacturing.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7899289A JPH02255204A (en) | 1989-03-29 | 1989-03-29 | Plug for piercing and rolling for production of steel pipe |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7899289A JPH02255204A (en) | 1989-03-29 | 1989-03-29 | Plug for piercing and rolling for production of steel pipe |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH02255204A true JPH02255204A (en) | 1990-10-16 |
Family
ID=13677394
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7899289A Pending JPH02255204A (en) | 1989-03-29 | 1989-03-29 | Plug for piercing and rolling for production of steel pipe |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH02255204A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2008731A1 (en) * | 2006-03-28 | 2008-12-31 | Sumitomo Metal Industries Limited | Mandrel bar for rolling of high alloy, method for surface treatment of the mandrel bar, method for manufacture of the mandrel bar, and method for operation of seamless steel pipe production apparatus |
-
1989
- 1989-03-29 JP JP7899289A patent/JPH02255204A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP2008731A1 (en) * | 2006-03-28 | 2008-12-31 | Sumitomo Metal Industries Limited | Mandrel bar for rolling of high alloy, method for surface treatment of the mandrel bar, method for manufacture of the mandrel bar, and method for operation of seamless steel pipe production apparatus |
| EP2008731A4 (en) * | 2006-03-28 | 2012-10-03 | Sumitomo Metal Ind | Mandrel bar for rolling of high alloy, method for surface treatment of the mandrel bar, method for manufacture of the mandrel bar, and method for operation of seamless steel pipe production apparatus |
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