JPS6130624A - Manufacture of austenitic stainless steel tube - Google Patents
Manufacture of austenitic stainless steel tubeInfo
- Publication number
- JPS6130624A JPS6130624A JP15388484A JP15388484A JPS6130624A JP S6130624 A JPS6130624 A JP S6130624A JP 15388484 A JP15388484 A JP 15388484A JP 15388484 A JP15388484 A JP 15388484A JP S6130624 A JPS6130624 A JP S6130624A
- Authority
- JP
- Japan
- Prior art keywords
- cold working
- tube
- solution heat
- heat treatment
- working
- 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.)
- Granted
Links
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
Description
【発明の詳細な説明】
〈産業上の利用分野〉
この発明は極整細粒のオーステナイト結晶粒度を有する
オーステナイトステンレス鋼管の製造方法に関する。DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for manufacturing an austenitic stainless steel pipe having an extremely fine austenite crystal grain size.
〈従来技術〉
JIS−8US821TP、 D工N17440−45
41等に規定される継目無オーステナイトステンレス鋼
管は、耐食性、耐熱性、密接性にすぐれるとともに、T
iの添加により灰化物の安定化を図って耐粒界腐食性全
向上させた銅賞で、耐食耐熱を要する配管、熱交換器等
に広く用いられている。最近、寒冷地において耐衝撃性
を要求される場所に使用される上記継目無ステンレヌ鋼
gに対して、オーステナイト結晶粒度(以下単に粒度と
いう)をl’&+11(JIS)もl〜くけそれ以上の
極整細粒とするようにという要求が提示された。しかし
上記継目無ヌテンレヌ鋼管は一般に、ロール穿孔製管法
(マンネスマン製管法〕′!、たは熱間押出し製管法(
ユジーヌ・セジュルネ製管法)によって製造されている
が、これらの製管法による製造のままでは上記のような
要求は到底満足できるものではない。<Prior art> JIS-8US821TP, D engineering N17440-45
Seamless austenitic stainless steel pipe specified by 41 etc. has excellent corrosion resistance, heat resistance, and tightness, and has T
Bronze Award, which has completely improved intergranular corrosion resistance by stabilizing the ash by adding i, and is widely used in piping, heat exchangers, etc. that require corrosion resistance and heat resistance. Recently, the austenite grain size (hereinafter simply referred to as grain size) has been changed to l'&+11 (JIS) for the seamless stainless steel g used in places where impact resistance is required in cold regions. A request was made to make the grains extremely fine. However, the above-mentioned seamless steel pipes are generally produced using the roll perforation method (Mannesmann method) or the hot extrusion method (
However, the above-mentioned requirements cannot be satisfied at all if these pipe manufacturing methods are used.
すなわち、前記製管法はいずれも1200℃前後の亮温
領域における加工であるから、この製管まkで粒子f歯
を11又はこれ以上の細粒にすることが不可能であり、
かつ若干の製管条件の変動によって、管群及び同一管内
での長手方向に粒度パラッキが存在する。That is, since all of the above-mentioned pipe-making methods are processed in a light temperature region of around 1200°C, it is impossible to make the particle f teeth into 11 or more fine particles until this pipe-making process.
In addition, due to slight variations in tube manufacturing conditions, particle size cracks exist in the tube group and in the longitudinal direction within the same tube.
細粒化の一方法として、管に適当な加工度(断面減少率
にて示す。以下同じ)で冷間加工を加えた後所定温度に
加熱保持し急冷する溶体化熱処理を施して組織の再結晶
を図る方法が考えられるが、この方法によシ粒反N01
1以上の極整細粒を得ようとすると、冷間用ニー溶体化
熱処理のサイクルを何度も繰返す必要があって、経済的
に見合わない。One method for refining the grains is to cold-work the tube at an appropriate degree of working (indicated by area reduction rate; the same applies hereinafter), then apply solution heat treatment to heat and hold at a predetermined temperature and rapidly cool it to regenerate the structure. A method for crystallization is considered, but this method
In order to obtain one or more extremely fine grains, it is necessary to repeat the cold knee solution heat treatment cycle many times, which is not economically viable.
〈発明の目的〉
本発明は粒度がNo.11以上の極整細粒を有するオー
ステナイトステンレス鋼管を経済的に製造し得る方法を
提供しようとするものである。<Object of the invention> The present invention has a particle size of No. The present invention aims to provide a method for economically manufacturing an austenitic stainless steel pipe having extremely fine grains of 11 or more.
〈発明の構成〉
本発明者は上述した冷間用ニー溶体化熱処理による細粒
化の理論を基盤とし、この理論を利用して継目無オース
テナイトステンレス鋼管を粒度1+11以上の極整細粒
となす来月的な方法を見い出すべく、種々天験、研究を
行い、その結果、次のような知見を得た。すなわち、ロ
ール穿孔法、熱間押出し法による製造直後の管の粒度バ
ラツキを解消し目標に合致した高水準の細粒となすこと
を低コストにて達成するには、冷間用ニー溶体化熱処理
の工程を2回繰返すこととし、1回目ではきわめて大き
な加工度の冷間加工を加えてまず全体を細粒域に整粒に
しておき、2回目の適度な冷開加工により更に細粒化を
促進てせるようにするのが最も有利である。<Structure of the Invention> Based on the theory of grain refining by cold knee solution heat treatment described above, the present inventor utilizes this theory to create a seamless austenitic stainless steel pipe with extremely fine grains having a grain size of 1+11 or more. In order to find a method for next month, I conducted various miracles and research, and as a result, I obtained the following knowledge. In other words, in order to eliminate the variation in particle size of tubes immediately after manufacture by roll perforation method or hot extrusion method and to achieve a high level of fine particles that meet the target at a low cost, cold knee solution heat treatment is necessary. The process described above is repeated twice, and in the first step, a very large degree of cold working is applied to make the whole grain into a fine-grained region, and in the second time, a moderate cold-opening process is performed to further refine the grain. It is most advantageous to facilitate this.
本発明は上記知見に基いてなされたもので、ロール穿孔
製管法または熱間押出し製管法によって得た素管に、ま
ず加工度60(X以上の冷間加工を加えた後900〜1
050℃に加熱保持後急冷する中間溶体化熱処理を施し
、次いで加工度20%以上の冷間加工を加えた後900
〜1050℃に加熱保持後急冷する最終溶体化熱処理を
施すことを特徴とする、オーヌテナイト結晶粒度がNo
.11以上の極整細粒のオーステナイトステンレス鋼管
の製造方法、を要旨とする。The present invention has been made based on the above findings, and involves first applying cold working to a working degree of 60 (X or more) to a raw pipe obtained by a roll perforation pipe manufacturing method or a hot extrusion pipe manufacturing method.
After performing intermediate solution heat treatment by heating and holding at 050°C and rapidly cooling, then cold working with a working degree of 20% or more, 900°C
Aunutenite grain size is No. 1, which is characterized by performing final solution heat treatment by heating and holding at ~1050°C and then rapidly cooling.
.. The gist of the present invention is a method for manufacturing an austenitic stainless steel pipe with extremely fine grains of 11 or more.
第1図は本発明方法の工程を示した工程図で、同図によ
シ本発明方法の具体例を説明する。FIG. 1 is a process diagram showing the steps of the method of the present invention, and a specific example of the method of the present invention will be explained with reference to the figure.
図において、(1)は例えば熱間押出し製管法によ〕得
た管で、これを素材にまず第1次冷間加工工程(2)で
例えば加工度60%の冷間加工を加えた後、中間溶体化
熱処理工程(3)で大型加熱炉に装入して管全体を例え
ば1000℃に加熱し該温度に例えば2分間保持した後
水冷する溶体化熱処理を施す。In the figure, (1) is a tube obtained, for example, by the hot extrusion tube manufacturing method, and this material is first subjected to cold working at a working degree of 60% in the first cold working step (2). After that, in the intermediate solution heat treatment step (3), the tube is charged into a large heating furnace, and the entire tube is heated to, for example, 1000° C., held at this temperature for, for example, 2 minutes, and then cooled with water for solution heat treatment.
次いで第2次冷間加工工程(4)で例えば加工度30%
の冷開加工を加えた後、最終溶体化熱処理工程(5)で
上記中間溶体化熱処理と同じ条件の熱処理を施して製品
(6)を得る。Next, in the second cold working step (4), the working degree is, for example, 30%.
After the cold opening process, a final solution heat treatment step (5) is performed under the same conditions as the intermediate solution heat treatment to obtain a product (6).
次に本発明において冷間加工の加工度および溶体化熱処
理の加熱温度を上記の如く限定した理由を説明する。Next, the reason why the working degree of cold working and the heating temperature of solution heat treatment are limited as described above in the present invention will be explained.
第1回目の冷間加工の加工度を60%以上としたのは、
60%未満では加工度が不十分で中間溶体化熱処理を施
した場合に粒度の十分な整細粒化が得られないからであ
る。The reason why the degree of work in the first cold working was 60% or more was because
This is because if it is less than 60%, the degree of processing is insufficient and sufficient grain size cannot be obtained when intermediate solution heat treatment is performed.
第2回目の冷間加工の加工度を20X以上としたのは、
本発明の対象とするような鋼管の場合、20%未満では
溶体化処理において完全な再結晶が得られないからであ
る。The working degree of the second cold working was set to 20X or more because
This is because, in the case of steel pipes that are the object of the present invention, complete recrystallization cannot be obtained during solution treatment if the content is less than 20%.
次に中間および最終溶体化熱処理における加熱温度を9
00〜1050℃としたのは、900℃未満では再結晶
が不十分となるからであり、また同じ<1050℃を越
えると粒度が逆に粗粒化することになるからである。Next, the heating temperature in the intermediate and final solution heat treatment was set to 9
The reason for setting the temperature to be 00 to 1050°C is because recrystallization becomes insufficient if it is less than 900°C, and if it exceeds <1050°C, the grain size will become coarser.
なお溶体化熱処理における加熱後の保持時間については
特に規定はしないが、2分程度の短時間で十分である。Note that the holding time after heating in the solution heat treatment is not particularly specified, but a short time of about 2 minutes is sufficient.
また加熱保持後の急冷は水冷が適当である。Further, water cooling is suitable for rapid cooling after heating and holding.
なおまた、本発明における第1次冷間加工手段としては
、例えばコールドビルガーミ/l’による所謂冷間圧延
加工とするのが望ましい。その理由は本発明における第
1次冷間加工で必要な加工度60%以上の冷間加工をダ
イスとフ”フグを用いる所謂冷間抽伸加工1回で実施す
る場合には材料破断等の問題があって不可能であり、こ
のため冷間抽伸加工における加工限界とされる中50%
以下の加工度による少なくとも2回以上の、軟化処理を
介在させないが潤滑処理を介在させた繰返し抽伸作業と
なり、この点において作業工数大となるが、冷間圧延に
よる場合には何等問題なく60%以上の加工度の加工を
1回で実施しうるからである。Furthermore, as the primary cold working means in the present invention, it is desirable to use, for example, so-called cold rolling by cold rolling mill/l'. The reason for this is that if the cold working with a working degree of 60% or more required in the first cold working of the present invention is performed in one so-called cold drawing process using a die and a blowfish, problems such as material breakage occur. Therefore, the processing limit in cold drawing processing is 50%.
It is a repeated drawing operation performed at least twice with the following working degree without softening treatment but with lubrication treatment, which requires a large number of work hours, but in the case of cold rolling, there is no problem at 60%. This is because machining with the above degree of machining can be performed in one go.
〈発明の効果〉 次に失施例を掲げて本発明の詳細な説明する。<Effect of the invention> Next, the present invention will be explained in detail with reference to some examples.
熱間押出し製管法により製管した外径55.(Fll$
×肉厚6.5顛×長さ中4000頭の5US821’r
pのオーステナイトヌテンレヌ鋼管を素材に、冷間加工
における加工度および溶体化熱処理における加熱温度を
種々に変えて、本発明例および比較例としての、冷間加
工(第1回目)−中t[J体化熱処理−冷間加工(第2
回目)−最終溶体化熱処理による各種の試験を行った。Outer diameter 55. Made by hot extrusion pipe making method. (Fll$
× 5US821'r with wall thickness 6.5 mm × length 4000
Using an austenitic Nutenrene steel pipe of P as a raw material, the working degree in cold working and the heating temperature in solution heat treatment were variously changed, and cold working (first time) - medium t[ J body heat treatment - cold working (second
1st) - Various tests were conducted using final solution heat treatment.
結果を第2〜第4図のグラフに示す。The results are shown in the graphs of FIGS. 2-4.
第2図は第1回目の冷間用ニー中間溶体化熱処理材にお
ける粒度とその溶体化処理温度との関係を示すグラフで
、冷間加工(1回目〕の加工度がそれぞれ28%、49
%(比較例)、60%(本発明例)の8種類のものにつ
いて示す。Figure 2 is a graph showing the relationship between particle size and solution treatment temperature for the first cold knee intermediate solution heat treatment material, and shows that the working degree of cold working (first time) was 28% and 49%, respectively.
% (comparative example) and 60% (inventive example).
第3図は第2図に示した比較例(2](中間溶体化温f
f:1020℃)に、第2回目の冷間加工(加工度29
%)→最終溶体化熱処理を施した材における粒度と最終
溶体化温度との関係を示したグラフである。Figure 3 shows the comparative example (2) shown in Figure 2 (intermediate solution temperature f
f: 1020°C), then the second cold working (working degree 29
%) → is a graph showing the relationship between particle size and final solution temperature in materials subjected to final solution heat treatment.
第4図は第2図に示した本発明例(3)(中間溶体化温
度:1000’lU)に、第2回目の冷間加工(加工度
30%)→最終溶体化熱処理を施した材における粒度と
最終溶体化温度との関係を示したグラフである。Figure 4 shows the material obtained by subjecting Example (3) of the present invention shown in Figure 2 (intermediate solution temperature: 1000'lU) to second cold working (working degree 30%) → final solution heat treatment. 2 is a graph showing the relationship between particle size and final solution temperature at .
なお、上記第2〜第4図において、中間および最終の溶
体化熱処理における熱処理条件としては、各加熱温度に
2分間保持後水冷、とした。また同図における・印は素
材A、○印は素材B、Δ印は素材Cを示す記号である。In FIGS. 2 to 4 above, the heat treatment conditions for the intermediate and final solution heat treatments were water cooling after holding each heating temperature for 2 minutes. Further, in the same figure, the * mark is a symbol indicating material A, the ○ mark is a symbol indicating material B, and the Δ mark is a symbol indicating material C.
第2図に見る通り、比較例(1)は冷間加工(1回目)
Kおける加工度が28%と低過ぎたため、素材Aが95
0℃加熱において70%再結晶未了、1000℃加熱に
おいても10%再結晶未了を生じ、粒度の整細粒化が殆
ど進まなかった。As shown in Figure 2, comparative example (1) is cold working (first time)
Because the degree of processing in K was too low at 28%, material A was reduced to 95%.
When heated at 0°C, 70% recrystallization was not completed, and even when heated at 1000°C, 10% recrystallization was not completed, and grain size refinement hardly progressed.
比較例(2)は冷間加工(1回目)における加工度が4
9%となお不十分で、900t:加熱において素材Aに
10%再結晶未了を、また950℃加熱において素材B
に10%再結晶未了を生じ、素材A、素材Bの粒度は素
管段階の隔6から陥9程度にしかなっておらず、第3図
の最終製品段階でも素材A・素材Bの粒度はNTIII
に達せず不十分であった。Comparative example (2) has a working degree of 4 in cold working (first time).
9% is still insufficient, 900t: 10% recrystallization is not completed in material A in heating, and material B in heating at 950 ° C.
Recrystallization was incomplete by 10%, and the grain size of Material A and Material B was only about 9 in the gap from 6 in the raw tube stage, and even in the final product stage in Figure 3, the grain size of Material A and Material B was the same. is NTIII
This was not achieved and was insufficient.
これに対し本発明例(3)は第1回目の冷間加工におけ
る加工度が60%の高加工度であったため中間溶体化熱
処理後の段階で既に素材CはN011以上、素材B、素
材Aにおいても略々陥10以上の細粒域に整粒化され粒
度のバラツキが極めて小さくなり、最終製品においては
第4図に見るように素材A、素材B、素材Cのすべてk
おいてl’b11以上の極整細粒が得られた。On the other hand, in Example (3) of the present invention, the degree of workability in the first cold working was as high as 60%, so that material C was already N011 or higher, material B, and material A at the stage after the intermediate solution heat treatment. The grain size is also regulated to a fine grain area with a diameter of approximately 10 or more, and the variation in grain size is extremely small, and in the final product, as shown in Figure 4, all of Material A, Material B, and Material C are fine.
Very fine grains with l'b11 or more were obtained.
以上の説明から明らかなように、本発明によれば、冷間
用ニー溶体化熱処理の工程を僅か2回繰返すだけできわ
めて経済的に粒yF+411以上のオーステナイトヌテ
ンレス鋼の継目無鋼管を得ることができるものである。As is clear from the above description, according to the present invention, it is possible to obtain seamless steel pipes of austenitic nutless steel with grains of yF+411 or more in an extremely economical manner by repeating the cold knee solution heat treatment process only twice. It is something that can be done.
第1図は本発明の製造方法に基く工程図、第2図は第1
回目の冷間用ニー中間溶体化熱処理材における粒度とそ
の溶体化処理温度との関係を示すグラフ、第3図、第4
図は第2図に示した処理材の比較例(2)と本発明例(
3)に冷間抽伸−最終溶体化熱処理を施した材(最終製
品)における粒度と最終溶体化温度との関係を示すグラ
フで、第8図は比較例、第4図は本発明例の各場合を示
す。Fig. 1 is a process diagram based on the manufacturing method of the present invention, and Fig. 2 is a process diagram based on the manufacturing method of the present invention.
Graphs showing the relationship between the particle size and the solution treatment temperature in the second cold knee intermediate solution heat treatment material, Figures 3 and 4
The figure shows the comparative example (2) of the treated material shown in Figure 2 and the inventive example (
3) is a graph showing the relationship between particle size and final solution temperature in materials (final products) subjected to cold drawing and final solution heat treatment, FIG. 8 is a comparative example, and FIG. Indicate the case.
Claims (1)
て得た素管に、まず加工度60%以上の冷間加工を加え
た後900〜1050℃に加熱保持後急冷する中間溶体
化熱処理を施し、次いで加工度20%以上の冷間加工を
加えた後900〜1050℃に加熱保持後急冷する最終
溶体化熱処理を施すことを特徴とするオーステナイト結
晶粒度がNo.11以上の極整細粒を有するオーステナ
イトステンレス鋼管の製造方法。(1) An intermediate solution obtained by first applying cold working to a degree of working of 60% or more to a raw pipe obtained by roll perforation pipe manufacturing method or hot extrusion pipe manufacturing method, then heating and holding at 900 to 1050°C, and then quenching. The austenite crystal grain size is No. 1, which is characterized by applying chemical heat treatment, then cold working with a degree of working of 20% or more, and then performing final solution heat treatment in which the product is heated and held at 900 to 1050°C and then rapidly cooled. A method for manufacturing an austenitic stainless steel pipe having extremely fine grains of 11 or more.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15388484A JPS6130624A (en) | 1984-07-23 | 1984-07-23 | Manufacture of austenitic stainless steel tube |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP15388484A JPS6130624A (en) | 1984-07-23 | 1984-07-23 | Manufacture of austenitic stainless steel tube |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS6130624A true JPS6130624A (en) | 1986-02-12 |
JPH0526852B2 JPH0526852B2 (en) | 1993-04-19 |
Family
ID=15572215
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP15388484A Granted JPS6130624A (en) | 1984-07-23 | 1984-07-23 | Manufacture of austenitic stainless steel tube |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6130624A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150013820A1 (en) * | 2011-11-30 | 2015-01-15 | National Institute For Materials Science | Method for rolling/drawing nickel-free high-nitrogen stainless steel material, thin seamless tube of nickel-free high-nitrogen stainless steel, and method of manufacturing the same |
JP2016065314A (en) * | 2010-02-04 | 2016-04-28 | 三浦 春松 | Production method of high nitrogen stainless steel pipe for high pressure hydrogen gas storage container production with high intensity, high ductility, excellent corrosion resistance and heat resistance |
CN115505707A (en) * | 2022-09-22 | 2022-12-23 | 内蒙古北方重工业集团有限公司 | Grain size refinement manufacturing method of large-caliber TP316H stainless steel seamless steel pipe |
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---|---|---|---|---|
JPS5341617A (en) * | 1976-08-19 | 1978-04-15 | Wheeler Colin | Rotary machine |
JPS5681618A (en) * | 1979-12-04 | 1981-07-03 | Japan Steel Works Ltd:The | Grain fining method of austenite steel |
-
1984
- 1984-07-23 JP JP15388484A patent/JPS6130624A/en active Granted
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5341617A (en) * | 1976-08-19 | 1978-04-15 | Wheeler Colin | Rotary machine |
JPS5681618A (en) * | 1979-12-04 | 1981-07-03 | Japan Steel Works Ltd:The | Grain fining method of austenite steel |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2016065314A (en) * | 2010-02-04 | 2016-04-28 | 三浦 春松 | Production method of high nitrogen stainless steel pipe for high pressure hydrogen gas storage container production with high intensity, high ductility, excellent corrosion resistance and heat resistance |
US20150013820A1 (en) * | 2011-11-30 | 2015-01-15 | National Institute For Materials Science | Method for rolling/drawing nickel-free high-nitrogen stainless steel material, thin seamless tube of nickel-free high-nitrogen stainless steel, and method of manufacturing the same |
CN115505707A (en) * | 2022-09-22 | 2022-12-23 | 内蒙古北方重工业集团有限公司 | Grain size refinement manufacturing method of large-caliber TP316H stainless steel seamless steel pipe |
CN115505707B (en) * | 2022-09-22 | 2023-09-26 | 内蒙古北方重工业集团有限公司 | Grain size refinement manufacturing method of large-caliber TP316H stainless steel seamless steel pipe |
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