CN101857945B - Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate - Google Patents
Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate Download PDFInfo
- Publication number
- CN101857945B CN101857945B CN2009100814827A CN200910081482A CN101857945B CN 101857945 B CN101857945 B CN 101857945B CN 2009100814827 A CN2009100814827 A CN 2009100814827A CN 200910081482 A CN200910081482 A CN 200910081482A CN 101857945 B CN101857945 B CN 101857945B
- Authority
- CN
- China
- Prior art keywords
- temperature
- steel
- controlled rolling
- recrystallization zone
- 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.)
- Active
Links
Landscapes
- Heat Treatment Of Steel (AREA)
Abstract
The invention relates to a method for producing an Mo-free low-Nb X80 pipeline steel hot rolled steel plate. The method comprises the following steps of: preparing raw materials in a ratio; smelting the raw materials by using a converter or an electric furnace; refining the smelted raw materials out of the furnace; casting the refined raw materials; reheating a plate blank; and performing controlled rolling and controlled cooling. The method is characterized in that: the heating temperature of the plate blank is of between 1,100 and 1,250 DEG C; the starting temperature of the controlled rolling in a recrystallization zone is of between 1,080 and 1,200 DEG C; the final temperature of the controlled rolling in the recrystallization zone is of between 950 and 1,080 DEG C; the starting temperature of the controlled rolling in a non-recrystallization zone is of between 860 and 950 DEG C; the compression ratio of the controlled rolling in the non-recrystallization zone is more than or equal to 75 percent; the final rolling temperature is of between 730 and 860 DEG C; the final cooling temperature is of between 300 and 550 DEG C; the cooling rate is of between 10 and 35 DEG C/s; produced steel has acicular ferrite and bainite structures and meets the requirement of API SPEC 5L on the performance of X90 pipeline steel; and production-manufacturing is low.
Description
Technical field
The present invention relates to a kind of manufacture method of Mo-free low-Nb X80 pipeline steel hot rolled steel plate.
Background technology
Sweet natural gas is urgent further as the demand of the energy, will replace oil and becomes main energy derive, and utilizing the pipeline of long distance that Sweet natural gas is transported to the user from the grown place is a kind of safety and economic method.In order to reduce the cost of pipeline long-distance transportation, the long distance that particularly surpasses 1000 kilometers transports, and the high pressure sheet-metal duct is the total amount of the needed steel of (1) minimizing effectively; (2) cost of reduction conveying pipe; (3) cost of reduction pipeline laying.Therefore high-intensity high-tenacity X80 pipe line steel has obtained using widely in the numerous gas pipe line engineering in the world, for example the transfering natural gas from the west to the east two wires engineering of China etc.EUROPIPE company shows in the project of RUHRGAS, uses the X80 pipe line steel to compare with X70, by tube wall is thick from the thick 18.3mm that is reduced to X80 of the 20.8mm of X70, saved about 20,000 tons steel.Simultaneously, because the reduction of weight has also reduced the cost that transports pipeline and because thin walled welds has reduced the time of welding.The X80 pipe line steel, particularly low-cost, high performance X80 pipe line steel will be the preferred material of following international gas pipe line engineering.
The production cost of the X80 pipe line steel that generally uses is all comparatively expensive at present, in order to obtain preferable performance, has added more valuable Alloy Elements Mo and Nb.Existing a plurality of patents of invention before the present invention about the X80 pipe line steel, the patent documentation that retrieval obtains, with more approaching the having of the present invention: patent CN1715434A (applying date 20040630), name is called high-intensity high-tenacity X80 pipe line steel and hot rolled plate making process thereof, the content of its alloy element Nb is 0.02～0.08, the content of Mo is weight % less than 0.2～0.4.Patent CN101270441A (applying date 20070323), name is called a kind of economy type X 80 pipeline steel and production method thereof, and the content of its alloy element Nb is 0.04～0.15, and the content of Mo is weight % less than 0.5.Patent CN101008068A (applying date 20070125), name is called a kind of pipe line steel and ingredient control method thereof, and the content of its alloy element Nb is 0.05～0.07, and the content of Mo is weight % less than 0.24～0.29.
The intensity of the disclosed X80 pipe line steel of above patent documentation and toughness have all reached the X80 grade of steel requirement of API Spec5L standard code, but Mo in its alloying constituent and Nb constituent content are higher, thereby production cost is higher.
Satisfy in the every performance that guarantees material on the basis of technological standard requirement, based on existing comparatively sophisticated smelting and rolling technique, for reducing production costs, develop a kind of low-cost X80 pipe line steel of Mo-free low-Nb alloying element, and exploitation is at the production method of this low-cost X80 pipe line steel.
Summary of the invention
The manufacture method that the purpose of this invention is to provide a kind of Mo-free low-Nb X80 pipeline steel hot rolled steel plate.Solve mainly that existing X80 pipe line steel production cost is higher, manufacture difficulty is big and technical problem such as technology stability.
Technical scheme of the present invention is: a kind of Mo-free low-Nb X80 pipe line steel, the weight percent of its moiety is: C:0.04～0.07%, Mn:1.70～1.90%, Si:0.15～0.30%, S :≤0.003%, P :≤0.012%, Ni:0.15～0.30%, Ti :≤0.020%, Alt:0.015～0.040%, Nb:0.010～0.035%, N :≤0.005%, O :≤0.003%, Cu :≤0.30%, Cr:0.10～0.25%, B :≤0.0005%, Ca :≤0.005%, all the other are iron and inevitable impurity.
Mo-free low-Nb X80 pipe line steel composition design philosophy of the present invention is with ultralow C, high Mn, by adding microalloy elements such as micro-Ni, Cr, Cu, Ti, small amount of N b, Al alloying element, in conjunction with TMCP technology, obtaining acicular ferrite+bainite is main tissue, has excellent mechanical property to guarantee pipe line steel.The effect of its main moiety is as follows:
Carbon: be strengthening element most economical, the most basic in the steel, by solution strengthening and precipitation strength the intensity that improves steel there is obvious effect, but improve C content ductility, toughness and the welding property of steel had negative impact, thus modern age pipe line steel evolution be the process that constantly reduces C content.Reduce the toughness that C content helps to improve steel on the one hand, can improve the welding property of steel on the other hand.We know that pipe line steel can have good weldability when C content is lower than 0.11% according to the Graville graphic representation of C content in the steel, carbon equivalent and steel weldability relation.So the C content of current pipeline steel is generally less than 0.11%, then adopting C for Mo-free low-Nb X80 pipe line steel of the present invention is the design of 0.04～0.07% C content.
Manganese:, be that compensation reduces the main and most economical strengthening element that causes loss of strength in the pipe line steel because of C content by the intensity of solution strengthening raising steel.Mn still enlarges the element of γ phase region, can reduce the γ → α transformation temperature of steel, helps to obtain tiny phase-change product, can improve toughness, the reduction ductile-brittle transition temperature of steel.Therefore the Mn content to Mo-free low-Nb X80 pipe line steel designs in 1.70～1.90% scopes.
Chromium: be to enlarge the γ phase region, separate out ferrite earlier when postponing γ → α phase transformation and form, promote the principal element that acicular ferrite forms, phase-change organization plays an important role to control, at certain cooling conditions with stop being lower than in the Ultra-low carbon pipe line steel under the rolling temperature 0.35% Cr and just can obtain tangible acicular ferrite and bainite structure, change to the low temperature direction because of phase transformation simultaneously, can make and organize further refinement, mainly be the intensity that improves steel by the phase transformation strengthening of tissue.The present invention chooses chromium: 0.10～0.25%.
Copper, nickel: can improve the intensity of steel by the solution strengthening effect, Cu can also improve the solidity to corrosion of steel simultaneously, and the adding of Ni mainly is to improve the red brittleness that Cu easily causes in steel, and useful to toughness.In thick specification pipe line steel, also can compensate the strength degradation that the increase because of thickness causes.The present invention chooses copper: nickel≤0.30%: 0.15～0.30%.
Titanium: be strong solid N element, the stoichiometric ratio of Ti/N is 3.42, utilizes the Ti fixing following N of 60ppm in the steel just about 0.02%, can form the TiN precipitated phase of tiny high-temperature stable when sheet billet continuous casting.Austenite crystal when this tiny TiN particle can hinder the slab reheat is effectively grown up, and simultaneously the impelling strength of improving welded heat affecting zone is had obvious effect.The present invention chooses≤and 0.020%.
Niobium: be one of topmost element in the modern microalloying pipe line steel, fairly obvious to the effect of grain refining.Separate out the austenitic answer of obstruction deformation, recrystallize by course of hot rolling NbC strain inducing, make the rolling deformation austenite structure in non-recrystallization zone when phase transformation, change tiny phase-change product into through controlled rolling and controlled chilling, so that steel has high strength and high tenacity.This patent is exactly to cooperate suitable C content to improve the effect of the content performance NbC of Nb, and the present invention chooses 0.010～0.035%.
Aluminium: be the element that adds for deoxidation in the steel, add an amount of Al and help crystal grain thinning, improve the toughness and tenacity of steel.The present invention chooses aluminium: 0.015～0.040%.
Sulphur, phosphorus: be unavoidable impurities element in the steel, it is low more good more to wish.By super low sulfur and Ca processing sulfide is carried out inclusion morphology control, can make pipe line steel have high impelling strength and good anti-HIC performance.
Therefore, have high-intensity high-tenacity and good characteristics such as welding property at microalloying acicular ferrite and bainite structure, based on material reinforcement theories such as refined crystalline strengthening, precipitation strength and dislocations strengthenings, the composition design with acicular ferrite and bainite structure Mo-free low-Nb X80 pipe line steel has been adopted the composition design of Ni, Cr, Cu alloying and the suitable Al of adding of lower carbon content, super low sulfur and phosphorus, Nb, Ti microalloying, control tissue.Hot rolling technology has adopted the hot mechanical treatment technology of controlled rolling and controlled cooling, carries out the organizational controls of the finished product by reasonable component and technology, to obtain to have the acicular ferrite+carbon bainite tissue of high-intensity high-tenacity.
Table 1 has shown different on chemical ingredients of the steel addressed in steel of the present invention and the document.
The comparison of table 1 steel of the present invention and prior art chemical ingredients
Analyze difference with the prior art of the present invention: compare with patent documentation 1,2 and 3, composition of the present invention is simple relatively, employing is based on C, Mn, Ni, Cr, Cu, Ti alloy, add alloying elements such as minor N b, Al, do not add alloying elements such as Mo, V, simplify steel making working procedure, reduced cost.
The operational path of Mo-free low-Nb X80 line steel hot rolling board fabrication method of the present invention is as follows: by technical scheme get the raw materials ready, electrosmelting is lived in converter, external refining, casting, slab reheat, controlled rolling, controlled chilling.Hot rolling technology carries out following control:
(1) slab heating temperature: 1100～1250 ℃;
(2) the beginning temperature of recrystallization zone controlled rolling: 1080～1200 ℃;
(3) final temperature of recrystallization zone controlled rolling: 950～1080 ℃;
(4) the beginning temperature of non-recrystallization zone controlled rolling: 860～950 ℃;
(5) non-recrystallization zone controlled rolling compression ratio: 〉=75%;
(6) stop rolling temperature: 730～860 ℃;
(7) stop cooling temperature: 300～550 ℃;
(8) speed of cooling: 10～35 ℃/s.
The invention effect
Compare with pipe line steel composition in the past, the present invention has lower C content (0.04～0.07%), lower Nb content (0.010～0.035%) on alloy formula, do not add Mo and V element, and composition simplicity of design and cost are lower; Higher Ni (0.15～0.30), Cr (0.10～0.25) content, the precipitation strength effect that has made full use of the Ni element and the phase transformation strengthening and the solution strengthening effect of Cr element, cooperate controlled rolling process, not only improved The comprehensive performance, and can take hot rolling production technique flexibly, boost productivity, consider suitably to add Cu simultaneously, Ti, elements such as Al, this element cooperates the product of being produced to have higher intensity, low-temperature flexibility and good welding property, and certain corrosion resistance nature arranged, make pipe line steel have good crack arrest ability, the steel of producing has acicular ferrite+bainite structure, satisfy API SPEC 5L fully to X90 pipe line steel performance demands, and can reduce manufacturing cost and increase the production manufacturability.
Embodiment
The chemical ingredients of embodiment 1～3, processing parameter and results of property are as follows:
● chemical ingredients
● hot rolling technology
Operational path is as follows: by technical scheme get the raw materials ready, electrosmelting is lived in converter, external refining, casting, slab reheat, controlled rolling, controlled chilling.
Processing parameter is as follows:
(1) slab heating temperature: 1120～1210 ℃;
(2) the beginning temperature of recrystallization zone controlled rolling: 1080～1170 ℃;
(3) final temperature of recrystallization zone controlled rolling: 950～1050 ℃;
(4) the beginning temperature of non-recrystallization zone controlled rolling: 860～930 ℃;
(5) non-recrystallization zone controlled rolling compression ratio: 〉=75%;
(6) stop rolling temperature: 730～860 ℃;
(7) stop cooling temperature: 300～500 ℃;
(8) speed of cooling: 12～30 ℃/s.
● results of property
The metallographic structure of hot-rolled steel sheet of the present invention is acicular ferrite+bainite, carries out mechanics, summer ratio impact, DWTT experiment respectively, and experimental result is as follows:
Trial-production hot-rolled steel sheet service check result
(annotate: stretch, impact to horizontal; Tension specimen width 38mm, gauge length 50.8mm; Charpy bar is of a size of 10 * 10 * 55mm; Horizontal clod wash d=2a, 180 °, the result is intact.)
The performance of the pipe line steel of producing according to technique scheme reaches following requirement:
(1) tensile property, target: R
T0.5=555～690MPa, R
m=625～825MPa.
(2) the v-notch summer is than impacting performance, target: test temperature-20 ℃, and the ballistic work of 10mm * 10mm * 55mm sample is single 〉=170J, mean value 〉=220J; Shear area is single 〉=and 80%, average 〉=90%.
(3) DWTT (Drop-Weight Tear Test (DWTT)) performance, target: test temperature-15 ℃, average shear interview SA% 〉=85%, single SA% 〉=70%.
(4) horizontal cold-bending property, target: d=2a (d is a bending diameter, and a is a steel plate thickness) is 180 °, intact.
(5) metallographic structure, target: grain fineness number (ASTM E112): 10 grades or thinner.Be organized as acicular ferrite+bainite structure.
Claims (1)
1. the manufacture method of a Mo-free low-Nb X80 pipeline steel hot rolled steel plate, it is characterized in that: moiety is by weight percentage: C:0.04～0.07%, Mn:1.70～1.90%, Si:0.15～0.30%, S :≤0.003%, P :≤0.012%, Ni:0.15～0.30%, Ti :≤0.020%, Alt:0.015～0.040%, Nb:0.010～0.035%, N :≤0.005%, O :≤0.003%, Cu :≤0.30%, Cr:0.10～0.25%, B :≤0.0005%, Ca :≤0.005%, all the other are iron and inevitable impurity; Get the raw materials ready by proportioning, carry out converter or electrosmelting then, external refining, casting, the slab reheat, controlled rolling and controlled chilling is characterized in that: slab heating temperature: 1100～1250 ℃; The beginning temperature of recrystallization zone controlled rolling: 1080～1200 ℃; The final temperature of recrystallization zone controlled rolling: 950～1080 ℃; The beginning temperature of non-recrystallization zone controlled rolling: 860～950 ℃; Non-recrystallization zone controlled rolling compression ratio: 〉=75%; Stop rolling temperature: 730～860 ℃; Stop cooling temperature: 300～550 ℃; Speed of cooling: 10～35 ℃/s.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100814827A CN101857945B (en) | 2009-04-08 | 2009-04-08 | Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2009100814827A CN101857945B (en) | 2009-04-08 | 2009-04-08 | Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101857945A CN101857945A (en) | 2010-10-13 |
| CN101857945B true CN101857945B (en) | 2011-09-07 |
Family
ID=42944101
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2009100814827A Active CN101857945B (en) | 2009-04-08 | 2009-04-08 | Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN101857945B (en) |
Families Citing this family (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102465236B (en) * | 2010-11-18 | 2013-07-31 | 中国石油天然气集团公司 | Method for producing X70 or X80 high-strain steel tube |
| CN102154587B (en) * | 2011-05-25 | 2013-08-07 | 莱芜钢铁集团有限公司 | Pipe line steel for high linear energy welding and manufacturing method thereof |
| CN102230128A (en) * | 2011-06-02 | 2011-11-02 | 首钢总公司 | Low-cost X70 pipeline steel plate and preparation method thereof |
| CN102851614B (en) * | 2011-06-28 | 2015-09-02 | 鞍钢股份有限公司 | Low-yield-ratio X80 pipeline steel hot-rolled coil and manufacturing method thereof |
| CN103233185B (en) * | 2013-05-10 | 2015-10-14 | 武汉钢铁(集团)公司 | A kind of X100 pipeline steel and production method thereof |
| CN103397260B (en) * | 2013-07-30 | 2015-08-26 | 首钢总公司 | A kind of Thin Specs high tenacity X80 hot-rolled steel sheet and production method thereof |
| CN103484764B (en) * | 2013-09-11 | 2015-09-30 | 首钢总公司 | Ti precipitation strength type superhigh-strength hot rolls thin plate and production method thereof |
| CN103526129B (en) * | 2013-09-27 | 2015-07-15 | 济钢集团有限公司 | Thick-specification acid-corrosion-resisting X65 pipeline steel plate and manufacturing method thereof |
| CN105779904B (en) * | 2014-12-23 | 2018-02-27 | 鞍钢股份有限公司 | Low-cost X80 straight welded pipe and preparation method thereof |
| CN104651717B (en) * | 2015-02-27 | 2017-08-29 | 内蒙古包钢钢联股份有限公司 | A kind of X80 steel-grade low temperature seamless pipeline steel tube and its production method containing rare earth |
| CN108728757A (en) * | 2017-04-24 | 2018-11-02 | 鞍钢股份有限公司 | Low-temperature L450M pipeline steel and manufacturing method thereof |
| CN109112402B (en) * | 2018-09-04 | 2020-10-27 | 鞍钢股份有限公司 | Steel plate for VC (polyvinyl chloride) nanoparticle reinforced X80 plastic pipe and manufacturing method thereof |
| CN111286672B (en) * | 2020-03-25 | 2022-03-29 | 江苏省沙钢钢铁研究院有限公司 | Needle-shaped ferrite type X60-grade HIC-resistant pipeline steel and rolling method thereof |
-
2009
- 2009-04-08 CN CN2009100814827A patent/CN101857945B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN101857945A (en) | 2010-10-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101857945B (en) | Method for producing Mo-free low-Nb X80 pipeline steel hot rolled steel plate | |
| CN100398684C (en) | Superhigh strength X100 pipeline steel and its hot rolled plate making process | |
| CN101397626B (en) | High intensity and high-toughness hot-rolled steel sheet and method for producing the same | |
| CN102168229B (en) | Weather resistant steel plate and manufacturing method thereof | |
| CN103352167B (en) | A kind of low yield strength ratio high strength bridge steel plate and manufacture method thereof | |
| JP6466582B2 (en) | Yield strength 800 MPa class high strength steel and method for producing the same | |
| CN103014554B (en) | Low-yield-ratio high-tenacity steel plate and manufacture method thereof | |
| CN102277530B (en) | Pipeline steel with thickness more than or equal to 25mm for deep sea and production method thereof | |
| CN102021497A (en) | X80 pipeline steel hot-rolled plate coil and manufacturing method thereof | |
| CN108546885B (en) | L555M pipeline steel with excellent low-temperature toughness and manufacturing method thereof | |
| CN102953018B (en) | High-strength pipeline steel, steel pipe and manufacture method thereof | |
| CN101270441B (en) | Economy type X80 pipeline steel and producing method thereof | |
| CN103866204B (en) | The large sstrain X80 dual phase sheet steel that the large soft reduction process of a kind of low temperature is produced | |
| CN106854732A (en) | The high tenacity low-yield-ratio fire resistant weathering steel and its production method of tensile strength >=600MPa | |
| CN101376947A (en) | High strength X90 pipeline steel and production method thereof | |
| CN105586529B (en) | A kind of 890MPa grade high-strengths steel, steel pipe and its manufacture method | |
| CN109957712A (en) | Low-hardness X70M pipeline steel hot-rolled plate coil and manufacturing method thereof | |
| CN103510003B (en) | A kind of large diameter pipeline Chinese People's Anti-Japanese Military and Political College is out of shape heterogeneous X100 High Strength Steel Plate and manufacture method thereof | |
| CN1318631C (en) | Method for producing high strength high toughness X80 pipeline steel and its hot-rolled plate | |
| CN102796967A (en) | 800 MPa economic corrosion-resistance and high-strength steel plate | |
| CN102400054A (en) | X80 pipeline steel for straight-seam electric resistance welding pipe and method for manufacturing hot-rolled coil thereof | |
| CN102400062B (en) | Low yield ratio and ultrahigh strength X130 pipeline steel | |
| CN110964991A (en) | Pipeline steel with HIC (hydrogen induced cracking) resistance and large deformation resistance and manufacturing method thereof | |
| CN101967606A (en) | Hot rolled steel strip for straight slit electric resistance welding petroleum casing pipe and production method thereof | |
| CN103469098A (en) | X80 pipeline steel with good HIC (hydrogen induced cracking) resistance and production method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant |