GB2137539A - Manufacturing seamless steel pipe - Google Patents
Manufacturing seamless steel pipe Download PDFInfo
- Publication number
- GB2137539A GB2137539A GB08407887A GB8407887A GB2137539A GB 2137539 A GB2137539 A GB 2137539A GB 08407887 A GB08407887 A GB 08407887A GB 8407887 A GB8407887 A GB 8407887A GB 2137539 A GB2137539 A GB 2137539A
- Authority
- GB
- United Kingdom
- Prior art keywords
- production
- temperature
- seamless steel
- iron
- finished
- 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
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 13
- 239000010959 steel Substances 0.000 title claims abstract description 13
- 238000005096 rolling process Methods 0.000 claims abstract description 15
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000001816 cooling Methods 0.000 claims abstract description 14
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 7
- 229910052742 iron Inorganic materials 0.000 claims abstract description 7
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims abstract description 6
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims abstract description 6
- 238000003303 reheating Methods 0.000 claims abstract description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 5
- 229910052782 aluminium Inorganic materials 0.000 claims abstract description 4
- 229910052796 boron Inorganic materials 0.000 claims abstract description 4
- 238000010438 heat treatment Methods 0.000 claims abstract description 4
- 239000012535 impurity Substances 0.000 claims abstract description 4
- 239000000203 mixture Substances 0.000 claims abstract description 4
- 229910052750 molybdenum Inorganic materials 0.000 claims abstract description 4
- 239000010955 niobium Substances 0.000 claims abstract description 4
- 229910052757 nitrogen Inorganic materials 0.000 claims abstract description 4
- 239000010936 titanium Substances 0.000 claims abstract description 4
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 4
- ZOXJGFHDIHLPTG-UHFFFAOYSA-N Boron Chemical compound [B] ZOXJGFHDIHLPTG-UHFFFAOYSA-N 0.000 claims abstract description 3
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims abstract description 3
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000005864 Sulphur Substances 0.000 claims abstract description 3
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 3
- 239000004411 aluminium Substances 0.000 claims abstract description 3
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims abstract description 3
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims abstract description 3
- 239000011733 molybdenum Substances 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
- GUCVJGMIXFAOAE-UHFFFAOYSA-N niobium atom Chemical compound [Nb] GUCVJGMIXFAOAE-UHFFFAOYSA-N 0.000 claims abstract description 3
- 238000000034 method Methods 0.000 claims description 16
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 3
- 230000000704 physical effect Effects 0.000 description 4
- 238000005496 tempering Methods 0.000 description 3
- 229910045601 alloy Inorganic materials 0.000 description 2
- 239000000956 alloy Substances 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 239000011572 manganese Substances 0.000 description 2
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- 229910001566 austenite Inorganic materials 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 229910001562 pearlite Inorganic materials 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000000284 resting effect Effects 0.000 description 1
- 238000002791 soaking Methods 0.000 description 1
- 230000003068 static effect Effects 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/001—Ferrous alloys, e.g. steel alloys containing N
-
- 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
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
A seamless steel pipe having particularly fine grain structure is produced using steel of the following composition:- 0.02 - 0.12 % Carbon, 1.3 - 2.2 % Manganese, 0.001 - 0.01 % Sulphur, 0.01 - 0.04 % Titanium, 0.02 - 0.06 % Niobium, 0.003 - 0.008 % Nitrogen, 0.03 - 0.05 % Aluminium, the remainder being iron, unavoidable impurities and individually or in any combination with themselves or the iron:- up to 0.3 % Molybdenum, up to 0.5 % Nickel, 0.001 - 0.003 % Boron, The production method comprises heating a rolled or continuously cast rod to a drawing temperature of 1150 to 1220 DEG C; pre-forming in one or more production stages to an hollow body with substantially the finished wall thickness; reheating the body for 5 to 20 minutes at 700 to 850 DEG C; longitudinal rolling to the finished pipe dimensions; and subsequent cooling.
Description
SPECIFICATION
Method for the production of seamless steel pipes
The invention relates to a method for the production of seamless steel pipes. Particularly it is concerned with the production of st(ch pipes having a yield point of at least 600 N/mm2 and impact work of at least 210 J at 0 C on longitudinal test pieces. Such pipes have especial application in the oil industry.
Seamless pipes with the above properties are typically produced from steels with approximately 0.4% C and, if required, with hardness-raising alloy elements and are tempered as finished pipes. Because of the alloy elements and the tempering, production is costly and intensive, particularly in respect of heat requirements.
According to another proposai, in the production of pipes of a steel with a similarly high C- and manganese content, pipes are normalised between the pre- and finish- forming and after the finish-forming are quenched by approximately 100C to a temperature below Ar 1. This type of production is indeed less costly, but does not allow the production of pipes with such high toughness values as are contemplated herein.
The present invention seeks to simplify the production of seamless steel pipes and in addition to also improve it in terms of quality. A particularly fine grain structure is sought to be achieved. According to the invention a seamless steel pipe having the above physical properties is produced using steel of the following composition:
0.02 - 0.12 % Carbon,
1.3 - 2.2 % Manganese,
0.001 - 0.01 % Sulphur,
0.01 - 0.04 % Titanium,
0.02 - 0.06 % Niobium,
0.003 - 0.008 % Nitrogen,
0.03 - 0.05 % Aluminium,
the remainder being iron, unavoidable impurities and individually or in any combination with
themselves or the iron;
upto 0.3 % Molybdenum,
upto 0.5 % Nickel,
0.001 - 0.003 % Boron.
The production method comprises heating a said rod to a drawing temperature of 1150 to 1220"C; pre-forming in one or more production stages to an hollow body with substantially the finished wall thickness; reheating the body for 5 to 20 minutes at 700 to 850"C; longitudinal rolling to the finished pipe dimensions; and subsequently cooling.
The method of the invention is able to be carried out on all appropriate installations for the production of seamless pipes. The piercing of the rods can take place in the skew-rolling mill or in the piercing press at the given drawing temperature. The stretching of the perforated piece can be carried out at the same heat on a continuous train or on a plug train. It is also possible to carry out the stretching on a pilger train. The stretching, at which principally the wall thickness is reduced with a pipe internal diameter remaining approximately the same, produces a hollow body which is many times longer than the length of the pierced piece. In all cases it is usual that a deformation of 40% is achieved. In the subsequent longitudinal rolling, as a rule the diameter is reduced, with the wall thickness remaining approximately the same.The extrusion press is also suitable for the method if the resulting pipe string is additionally longitudinally rolled.
For the method, the adherence to temperatures and analysis thresholds is an absolute prerequisite. Even relatively small deviations can cause considerable deviations in the product.
The drawing temperature appiies to cold charges. The resting period is to be selected according to the thickness of the rods. The reheating is of particular importance. It is intended that the formation of pearlite after pre-forming does not come fully into effect and that the carbon which is not able to be dissolved in the ferrite is balanced out in the residual austenite during the reheating period and thereby the preparations are made for a very fine grain structure on cooling after the longitudinal rolling. In addition the reheating temperature is an advantageous forming temperature for the longitudinal rolling, as a further contribution to the production of a fine-grained structure after the longitudinal rolling. Therefore, the cooling is also important.The cooling is preferably accomplished at a minimum rate of say, 6 C/Sec. This, however, is not so great that quenching must be necessarily carried out with water. With cooling in static air, only those relatively low values of the desired physical properties are able to be obtained. Generally, if the steps of the method disclosed herein are adhered to, very fine-grained bainite will result.
Cooling from a temperature in the range 600 - 450"C can take place as desired. Owing to the low carbon content of the allow there is no danger that martensite results if cooling takes place up to ambient temperature; however, cooling in air is to be preferred because of the small expenditure.
The physical properties of the seamless pipe produced in the method of the invention are further improved when, after cooling to ambient temperature, the pipes are tempered. Preferred tempering takes place at a temperature in the range 400 to 6500C and is maintained at temperatures in said range for 20 minutes.
The invention will now be iilustrated in the following examples:
A continuous ingot with 175 mm external diameter, has the following composition:
0.032% C; 1.92% Mn; 0.0024% S; 0.043% Al; 0.021% Ti; 0.27% Mo; 0.0023% B; 0.051 Nb; 0.0056% N; with
the remainder iron and the usual impurities.
The ingot is placed cold in a rotary furnace and is drawn after sufficient through-heating at 1150"C. Piercing takes place on a skew-rolling mill and the workpiece is stretched on a cylindrical rod in the so-called continuous rolling mill to the dimension of 152 mm external diameter, 14 mm wall thickness. This is a pre-forming of 75 /0 and the forming is to be carried out so smoothly that the hollow body cools down as little as possible below Ar 1, but rather is charged into the equalizing furnace at a slightiy higher temperature. The hollow body is heated equilibrantly by soaking at 780"C for 12 minutes. At this temperature, the finish-rolling also takes place on a reducing rolling mill to the finished dimension of 110.6 mm external diameter, 16 mm wall thickness. This is 30% finish-forming.
In Example A, cooling takes place in air. Subsequently, tempering took place for 30 minutes at 550"C.
In Example B, the cooling took place with water at approximately 1 5"C/s to 500"C and subsequently in air to ambient temperature. The physical properties of the pipes produced in the example methods were as follows:
Example A Example B
Yield point N/mm2: 605 693 Tensiie strength N/mm2: 749 828
Elongation at rupture %: 22 20 lmpactWorkj atO C: 230 272
The structure in both examples is completely bainitic.
Claims (7)
1.3 - 2.2 % Manganese,
0.001 - 0.01 % Sulphur,
0.01 - 0.04 % Titanium,
0.02 - 0.06 % Niobium,
0.003 - 0.008 % Nitrogen,
0.03 - 0.05 % Aluminium,
the remainder being iron, unavoidable impurities and individually or in any combination with
themselves or the iron;
upto 0.3 % Molybdenum,
upto 0.5 % Nickel,
0.001 - 0.003 % Boron.
2. A method according to Claim 1 wherein the longitudinal rolling is carried out with a deformation of at least 6%.
3. A method according to Claim 1 or Claim 2 wherein the finished pipe is cooled to ambient temperature using at least one of water and air.
4. A method according to Claim 3 wherein immediately after the rolling step the finished pipe is cooled to a temperature of between 600 and 450"C at a rate of at least 60C/s.
5. A method according to Claim 3 wherein immediately after the rolling step the finished pipe is cooled in air to ambient temperature.
6. A method according to any preceding Claim wherein after cooling to ambient temperature the product is tempered at a temperature in the range 400 to 650"C and is maintained at temperatures in said range for 20 minutes.
7. A method for the production of seamless steel pipes substantially as described herein with reference to the examples.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3311629A DE3311629C2 (en) | 1983-03-28 | 1983-03-28 | Process for the production of seamless steel tubes |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| GB8407887D0 GB8407887D0 (en) | 1984-05-02 |
| GB2137539A true GB2137539A (en) | 1984-10-10 |
| GB2137539B GB2137539B (en) | 1986-05-21 |
Family
ID=6195118
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08407887A Expired GB2137539B (en) | 1983-03-28 | 1984-03-27 | Manufacturing seamless steel pipe |
Country Status (5)
| Country | Link |
|---|---|
| JP (1) | JPS59182920A (en) |
| DE (1) | DE3311629C2 (en) |
| FR (1) | FR2543461B1 (en) |
| GB (1) | GB2137539B (en) |
| IT (1) | IT1173609B (en) |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0370588A1 (en) * | 1988-09-16 | 1990-05-30 | MANNESMANN Aktiengesellschaft | Method for producing high-strength seamless steel pipes |
| FR2643648A1 (en) * | 1989-02-28 | 1990-08-31 | Mannesmann Ag | PROCESS FOR PRODUCING OLEODUCTS OR ANALOGS WITHOUT WELDING |
| WO1998001589A1 (en) * | 1996-07-08 | 1998-01-15 | Mannesmann Ag | Process for producing weldless steel pipes |
| WO2004092423A1 (en) * | 2003-04-16 | 2004-10-28 | Tubos De Acero De Mexico, S.A. | Method for the production of a collar for installing an underwater pipeline and the product thus obtained |
| CN101829679A (en) * | 2009-03-09 | 2010-09-15 | 鞍钢股份有限公司 | Production method for improving impact toughness of hot-rolled oil well pipe coupling material |
| CN102224265A (en) * | 2008-11-20 | 2011-10-19 | 奥钢联管柱有限责任两合公司 | Method and apparatus for producing steel pipes having particular properties |
| US8601852B2 (en) | 2006-03-28 | 2013-12-10 | Nippon Steel & Sumitomo Metal Corporation | Method of manufacturing seamless pipe and tube |
| CN106269980A (en) * | 2016-08-30 | 2017-01-04 | 安吉县鹏大钢管有限公司 | A kind of preparation technology of seamless steel pipe |
| CN106391715A (en) * | 2016-08-30 | 2017-02-15 | 安吉县鹏大钢管有限公司 | Preparation process for martensite seamless steel pipe |
| CN108273850A (en) * | 2018-01-05 | 2018-07-13 | 衡阳华菱连轧管有限公司 | The test instrument on line method of middle carbon microalloy steel pipe |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63250418A (en) * | 1987-04-07 | 1988-10-18 | Nippon Steel Corp | Manufacture of line pipe combining high strength with low yield ratio |
| JP2525961B2 (en) * | 1991-02-07 | 1996-08-21 | 新日本製鐵株式会社 | Manufacturing method of high toughness seamless steel pipe with fine grain structure |
| CN104907352B (en) * | 2015-05-20 | 2017-01-04 | 湖州华特不锈钢管制造有限公司 | A kind of stainless steel tube production method for condenser |
| CN108704952A (en) * | 2018-05-18 | 2018-10-26 | 东阿县华通轴承配件有限公司 | A kind of bearing seamless steel tube production technique |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE973061C (en) * | 1941-02-20 | 1959-11-19 | Phoenix Rheinrohr Ag Vereinigt | Steel for seamless tubes |
| JPS54132421A (en) * | 1978-04-05 | 1979-10-15 | Nippon Steel Corp | Manufacture of high toughness bainite high tensile steel plate with superior weldability |
| DE3127373C2 (en) * | 1981-07-09 | 1985-08-29 | Mannesmann AG, 4000 Düsseldorf | Process for the manufacture of seamless steel tubes for the petroleum industry |
| HU189130B (en) * | 1982-04-16 | 1986-06-30 | Csepel Muevek Tervezoe Es Kutato Intezete,Hu | Method for producing tube sorts usable equally as structural, mining and high-tensile tube of improved characteristic from combined microalloyed steels |
-
1983
- 1983-03-28 DE DE3311629A patent/DE3311629C2/en not_active Expired
-
1984
- 1984-03-26 FR FR8404662A patent/FR2543461B1/en not_active Expired
- 1984-03-27 GB GB08407887A patent/GB2137539B/en not_active Expired
- 1984-03-28 IT IT20259/84A patent/IT1173609B/en active
- 1984-03-28 JP JP59060492A patent/JPS59182920A/en active Pending
Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0370588A1 (en) * | 1988-09-16 | 1990-05-30 | MANNESMANN Aktiengesellschaft | Method for producing high-strength seamless steel pipes |
| FR2643648A1 (en) * | 1989-02-28 | 1990-08-31 | Mannesmann Ag | PROCESS FOR PRODUCING OLEODUCTS OR ANALOGS WITHOUT WELDING |
| WO1998001589A1 (en) * | 1996-07-08 | 1998-01-15 | Mannesmann Ag | Process for producing weldless steel pipes |
| WO2004092423A1 (en) * | 2003-04-16 | 2004-10-28 | Tubos De Acero De Mexico, S.A. | Method for the production of a collar for installing an underwater pipeline and the product thus obtained |
| US8601852B2 (en) | 2006-03-28 | 2013-12-10 | Nippon Steel & Sumitomo Metal Corporation | Method of manufacturing seamless pipe and tube |
| CN102224265A (en) * | 2008-11-20 | 2011-10-19 | 奥钢联管柱有限责任两合公司 | Method and apparatus for producing steel pipes having particular properties |
| CN101829679A (en) * | 2009-03-09 | 2010-09-15 | 鞍钢股份有限公司 | Production method for improving impact toughness of hot-rolled oil well pipe coupling material |
| CN101829679B (en) * | 2009-03-09 | 2013-09-04 | 鞍钢股份有限公司 | Production method for improving impact toughness of hot-rolled oil well pipe coupling material |
| CN106269980A (en) * | 2016-08-30 | 2017-01-04 | 安吉县鹏大钢管有限公司 | A kind of preparation technology of seamless steel pipe |
| CN106391715A (en) * | 2016-08-30 | 2017-02-15 | 安吉县鹏大钢管有限公司 | Preparation process for martensite seamless steel pipe |
| CN106391715B (en) * | 2016-08-30 | 2018-06-05 | 安吉县鹏大钢管有限公司 | A kind of preparation process of martensitic seamless steel pipe |
| CN108273850A (en) * | 2018-01-05 | 2018-07-13 | 衡阳华菱连轧管有限公司 | The test instrument on line method of middle carbon microalloy steel pipe |
Also Published As
| Publication number | Publication date |
|---|---|
| GB2137539B (en) | 1986-05-21 |
| IT1173609B (en) | 1987-06-24 |
| FR2543461B1 (en) | 1987-05-07 |
| GB8407887D0 (en) | 1984-05-02 |
| IT8420259A0 (en) | 1984-03-28 |
| JPS59182920A (en) | 1984-10-17 |
| DE3311629C2 (en) | 1986-08-14 |
| DE3311629A1 (en) | 1984-10-11 |
| FR2543461A1 (en) | 1984-10-05 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |