CN117403128A - Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C - Google Patents
Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C Download PDFInfo
- Publication number
- CN117403128A CN117403128A CN202311312545.1A CN202311312545A CN117403128A CN 117403128 A CN117403128 A CN 117403128A CN 202311312545 A CN202311312545 A CN 202311312545A CN 117403128 A CN117403128 A CN 117403128A
- Authority
- CN
- China
- Prior art keywords
- percent
- temperature
- steel pipe
- nickel
- equal
- 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
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 title claims abstract description 50
- 229910052759 nickel Inorganic materials 0.000 title claims abstract description 22
- 229910000742 Microalloyed steel Inorganic materials 0.000 title claims abstract description 14
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 58
- 239000010959 steel Substances 0.000 claims abstract description 58
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 9
- 229910052742 iron Inorganic materials 0.000 claims abstract description 4
- 238000005096 rolling process Methods 0.000 claims description 38
- 238000005496 tempering Methods 0.000 claims description 18
- 239000000463 material Substances 0.000 claims description 14
- 238000010791 quenching Methods 0.000 claims description 13
- 230000000171 quenching effect Effects 0.000 claims description 13
- 238000010438 heat treatment Methods 0.000 claims description 12
- 238000002360 preparation method Methods 0.000 claims description 7
- 238000005266 casting Methods 0.000 claims description 6
- 238000004321 preservation Methods 0.000 claims description 6
- FBPFZTCFMRRESA-JGWLITMVSA-N D-glucitol Chemical compound OC[C@H](O)[C@@H](O)[C@H](O)[C@H](O)CO FBPFZTCFMRRESA-JGWLITMVSA-N 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 abstract description 17
- 230000008569 process Effects 0.000 abstract description 6
- 230000007547 defect Effects 0.000 abstract description 2
- 230000007704 transition Effects 0.000 abstract description 2
- 238000005204 segregation Methods 0.000 description 16
- 239000011572 manganese Substances 0.000 description 15
- 229910045601 alloy Inorganic materials 0.000 description 11
- 239000000956 alloy Substances 0.000 description 11
- 238000013461 design Methods 0.000 description 10
- 229910052757 nitrogen Inorganic materials 0.000 description 10
- 238000005728 strengthening Methods 0.000 description 10
- 238000001556 precipitation Methods 0.000 description 9
- 239000006104 solid solution Substances 0.000 description 9
- 239000011651 chromium Substances 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 238000007670 refining Methods 0.000 description 6
- 239000010936 titanium Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 5
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 4
- 238000003723 Smelting Methods 0.000 description 4
- 230000015572 biosynthetic process Effects 0.000 description 4
- 238000009749 continuous casting Methods 0.000 description 4
- 229910052698 phosphorus Inorganic materials 0.000 description 4
- 229910052719 titanium Inorganic materials 0.000 description 4
- 230000009466 transformation Effects 0.000 description 4
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 229910000851 Alloy steel Inorganic materials 0.000 description 2
- 229910000599 Cr alloy Inorganic materials 0.000 description 2
- 229910001182 Mo alloy Inorganic materials 0.000 description 2
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 description 2
- 229910001563 bainite Inorganic materials 0.000 description 2
- 229910052804 chromium Inorganic materials 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 238000010891 electric arc Methods 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 238000005087 graphitization Methods 0.000 description 2
- 230000000977 initiatory effect Effects 0.000 description 2
- 229910052748 manganese Inorganic materials 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 238000002844 melting Methods 0.000 description 2
- 229910052750 molybdenum Inorganic materials 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 238000010008 shearing Methods 0.000 description 2
- 238000004513 sizing Methods 0.000 description 2
- 238000009628 steelmaking Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- 229910000859 α-Fe Inorganic materials 0.000 description 2
- 229910001209 Low-carbon steel Inorganic materials 0.000 description 1
- 229910000617 Mangalloy Inorganic materials 0.000 description 1
- QFGIVKNKFPCKAW-UHFFFAOYSA-N [Mn].[C] Chemical compound [Mn].[C] QFGIVKNKFPCKAW-UHFFFAOYSA-N 0.000 description 1
- JKULTISBNPLSEA-UHFFFAOYSA-N [Ni].[Mo].[Mn] Chemical compound [Ni].[Mo].[Mn] JKULTISBNPLSEA-UHFFFAOYSA-N 0.000 description 1
- OGSYQYXYGXIQFH-UHFFFAOYSA-N chromium molybdenum nickel Chemical compound [Cr].[Ni].[Mo] OGSYQYXYGXIQFH-UHFFFAOYSA-N 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 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
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B19/00—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work
- B21B19/02—Tube-rolling by rollers arranged outside the work and having their axes not perpendicular to the axis of the work the axes of the rollers being arranged essentially diagonally to the axis of the work, e.g. "cross" tube-rolling ; Diescher mills, Stiefel disc piercers or Stiefel rotary piercers
- B21B19/04—Rolling basic material of solid, i.e. non-hollow, structure; Piercing, e.g. rotary piercing mills
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
- B21B37/78—Control of tube rolling
-
- 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
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
- C21D8/105—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of tubular bodies of ferrous alloys
-
- 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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/08—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for tubular bodies or pipes
- C21D9/085—Cooling or quenching
-
- 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
-
- 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/22—Ferrous alloys, e.g. steel alloys containing chromium with molybdenum or tungsten
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium
-
- 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
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/28—Ferrous alloys, e.g. steel alloys containing chromium with titanium or zirconium
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
-
- 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
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/009—Pearlite
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Crystallography & Structural Chemistry (AREA)
- Thermal Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Manufacturing & Machinery (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention relates to a gigapascal-grade non-nickel microalloy steel pipe with low temperature resistance of minus 120 ℃, which comprises the following components in percentage by mass: c:0.18 to 0.22 percent; si:0.17 to 0.35 percent; mn:0.40 to 0.45 percent; p is less than or equal to 0.012%; s is less than or equal to 0.003%; cr:0.95 to 1.10 percent; mo:0.80 to 0.88 percent; v:0.10 to 0.15 percent; ti is less than or equal to 0.03%; al:0.020-0.045%; the balance of iron and residual elements; the invention adopts the low-carbon Cr-Mo-V non-nickel quenched and tempered steel, can process the strength of the pipe to about 1000MPa, has a longitudinal impact energy of more than 80J at minus 120 ℃, has a toughness area of more than 75% of an impact fracture, and does not generate brittle transition; overcomes the defect that the common low-temperature resistant steel can not meet the requirement of low-temperature environment and column strength safety.
Description
Technical Field
The invention belongs to the technical field of steel pipes for oil and gas exploitation, and particularly relates to a non-nickel microalloy steel pipe with a low temperature of-120 ℃ resistant grade of gigapascals.
Background
With the continuous development of carbon capture and carbon sealing projects, the depth of oil gas exploitation in low-temperature environments such as polar regions is continuously increased, and the demands for high-strength low-temperature-resistant pipes are increasingly increased.
According to the state of the art of GB 3531-2014 Steel plate for Low temperature pressure Container and common Low temperature tubing, conventional Low temperature resistant materials are: low carbon manganese steel (C0.05-0.28%, mn 0.6-2%) with the lowest use temperature of about-60 ℃; the low alloy steel mainly comprises low nickel steel (Ni 2-4%), manganese nickel molybdenum steel (Mn 0.6-1.5%, ni 0.2-1.0%, mo 0.4-0.6%, C less than or equal to 0.25%), nickel chromium molybdenum steel (Ni 0.7-3.0%, cr 0.4-2.0%, mo 0.2-0.6%, C less than or equal to 0.25%), wherein the strength of the steel is higher than that of low carbon steel, and the lowest use temperature can reach about-110 ℃; the medium (high) alloy steel mainly comprises 6% of Ni steel, 9% of Ni steel and 36% of Ni steel, wherein 9% of Ni steel is widely applied steel for deep cooling, and the use temperature of the high nickel steel can be as low as-196 ℃.
CO 2 The vaporization temperature of the alloy is-78.5 ℃, the pipe is required to be least guaranteed to be low-temperature resistant below-80 ℃, the climates such as the polar region can be below-110 ℃, the conventional pipe products with low temperature resistance of-40 ℃ and low temperature resistance of-60 ℃ can not meet the requirements of service environments, nickel-containing and nickel-based materials can meet the low-temperature resistant requirements, but have high price and higher input cost, nickel metal is a critical aviation, aerospace and new energy material in the national resource strategy, meanwhile, the strength of the Ni-containing material can only reach 500-600 MPa, and even if the strength of 9% Ni material can only reach about 800MPa, the application requirements can not be met, and the economic requirements can not be met.
Therefore, the development of the non-nickel high-strength low-temperature-resistant microalloy material is not only the guarantee of realizing the aim of double carbon, but also the urgent need of the development of oil gas resources in a low-temperature environment.
Disclosure of Invention
The invention aims to provide a non-nickel microalloy steel pipe with the low temperature resistance of-120 ℃ in the gigapascal level, which comprises the following components in percentage by mass:
c:0.18 to 0.22 percent; si:0.17 to 0.35 percent; mn:0.40 to 0.45 percent; p is less than or equal to 0.012%; s is less than or equal to 0.003%; cr:0.95 to 1.10 percent; mo:0.80 to 0.88 percent; v:0.10 to 0.15 percent; ti is less than or equal to 0.03%; al:0.020-0.045%; the balance being iron and residual elements.
The alloy composition of the material is designed for the following reasons:
the material design is based on Cr-Mo-V microalloyed steel, adopts low C, mn design, reduces the generation of rolling strips caused by alloy segregation, enhances the solid solution strengthening effect of Cr and Mo alloy elements, reduces the precipitation proportion, and simultaneously achieves the technical requirements of high strength and low temperature resistance by the precipitation and grain refinement effect of V (C, N), and comprises the following specific components:
c:0.18-0.22%; adopting a low-carbon design, and improving the solid solution strengthening of Mo and Cr elements on the basis of meeting the requirement of V (C, N) precipitation strengthening so as to ensure the strength and higher toughness of the steel; when the content of C is lower than 0.18%, the strength cannot be ensured, but too high content of C not only can cause segregation, but also can greatly increase the segregation of Mn and P and reduce the low-temperature impact toughness;
si:0.17 to 0.35 percent; si is an effective deoxidizer and improves tempering resistance, but Si is an element that strongly promotes graphitization and is disadvantageous to the structure in which a large amount of carbide precipitation is desired, so Si should be as small as possible;
mn:0.40 to 0.45 percent; mn improves the strength and hardenability of steel, but Mn is an element which is easy to segregate, is easy to segregate with S, P in a grain boundary, and has caused component segregation to aggravate the formation of a strip shape, so that a low Mn design is adopted, and Mn-containing alloy is not added except Mn added in the composite deoxidation of molten steel;
p is less than or equal to 0.012%; since P is a key element causing cold embrittlement, the content of P must be reduced as much as possible, but the invention controls the content of P to be less than 0.12% in consideration of smelting cost, and reduces the influence of P by solid solution of other alloy elements.
S is less than or equal to 0.003%; s element is liable to segregate with Mn and other grain boundaries, not only the grain boundary strength is reduced, heat embrittlement is caused in the rolling process, but also the formation of band-like segregation is promoted, so that S is reduced to below 0.003% by external refining
Cr:0.95 to 1.10 percent; in the quenching process, cr is an element for strongly preventing bainite transformation, can effectively improve the hardenability of the steel, has tempering softening resistance, and can improve the mechanical strength of the steel;
mo:0.80 to 0.88 percent; the Mo element can obviously delay ferrite transformation time, reduce critical cooling rate and improve hardenability of steel; in addition, mo can reduce the segregation of P in the grain boundary by reducing the diffusion coefficient of P; meanwhile, the low-C design is adopted, so that the solid solution strengthening of Mo is increased, and the effect of improving the strength and the toughness is achieved;
v:0.10 to 0.15 percent; a certain amount of V element is separated out in the quenching and tempering heat treatment process, so that the crystal grains of the steel are refined, and the strength and the toughness are improved; on the other hand, when the content is too high, the strength is reduced, the room-temperature impact toughness is reduced, and the fluctuation of mechanical properties is larger;
ti: less than or equal to 0.03 percent; although a small amount of titanium can be combined with nitrogen to form high-melting point particles, so that grains can be refined, ti (N, C) is regular cubes or cubes, has obvious sharp corners and non-combination interfaces, is easy to form crack sources, causes crack initiation and expansion, has a large influence on low-temperature impact toughness, and therefore, needs to reduce the Ti content in a matrix;
al:0.020-0.045%; al is a strong deoxidizer, and is easy to combine with N to form AlN, and a certain Al content is maintained, so that the combination of N and Ti is reduced.
The balance of Fe and residual elements.
When in production and preparation, the round casting blank is subjected to electric furnace steelmaking, LF+VD external refining and arc continuous casting, hot rolled into a rolled tube, and then heat treatment is carried out to meet the requirement of 1000MPa strength performance.
In the preparation process of the steel pipe, the rolling ratio is 5-9, the rolling ratio is the deformation degree of the steel pipe along the rolling direction, and the calculation mode is the ratio of the cross section area of a casting blank to the cross section area of the steel pipe, and the larger the rolling ratio is, the larger the rolling direction deformation is.
In the preparation process of the steel pipe, a heat treatment mode adopts a quenching and tempering treatment method, namely, high-temperature tempering is carried out after quenching, the quenching temperature is 880-900 ℃, the heat preservation is carried out for 30 minutes, the tempering temperature is 680-720 ℃, and the heat preservation is carried out for 90 minutes.
Further, the steel pipe has a longitudinal impact energy at-120 ℃: VL (10 x 10) is more than or equal to 80J; transverse impact energy: VT (10 x 10) is equal to or greater than 60J.
Further, the yield strength of the steel pipe is 862 MPa-1034 MPa, and the tensile strength is more than or equal to 965MPa.
Further, the texture of the material after tempering is tempered sorbite, and the grain size is 9.0 grade or more.
The invention has the advantages and positive effects that:
the invention adopts the low-carbon Cr-Mo-V non-nickel quenched and tempered steel, can process the strength of the pipe to about 1000MPa, has a longitudinal impact energy of more than 80J at minus 120 ℃, has a toughness area of more than 75% of an impact fracture, and does not generate brittle transition; the low-temperature-resistant steel overcomes the defects that the lowest use temperature of common low-temperature-resistant steel does not reach the standard, the nickel or nickel-based material is high in price, the strength grade is low, and the requirements of low-temperature environment and column strength safety cannot be met.
Drawings
The technical solution of the present invention will be described in further detail below with reference to the accompanying drawings and examples, but it should be understood that these drawings are designed for the purpose of illustration only and thus are not limiting the scope of the present invention. Moreover, unless specifically indicated otherwise, the drawings are intended to conceptually illustrate the structural configurations described herein and are not necessarily drawn to scale.
FIG. 1 is a graph showing the relationship between the ratio of horizontal impact energy to vertical impact energy and the rolling ratio of a steel pipe in example 1 of the present invention;
FIG. 2 is a band segregation diagram in example 1 of the present invention;
FIG. 3 is a graph showing the longitudinal impact and shear ratio in example 2 of the present invention;
FIG. 4 is a graph showing the transverse impact power and shear ratio in example 2 of the present invention;
FIG. 5 is a graph showing the longitudinal impact and shear ratio in example 3 of the present invention;
FIG. 6 is a graph showing the transverse impact power and shear ratio in example 3 of the present invention;
Detailed Description
It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.
Example 1
The non-nickel microalloy steel pipe with the gigapascal low temperature resistance of-120 ℃ provided by the embodiment comprises the following components in percentage by mass:
c:0.18 to 0.22 percent; si:0.17 to 0.35 percent; mn:0.40 to 0.45 percent; p is less than or equal to 0.012%; s is less than or equal to 0.003%; cr:0.95 to 1.10 percent; mo:0.80 to 0.88 percent; v:0.10 to 0.15 percent; ti is less than or equal to 0.03%; al:0.020-0.045%; the balance being iron and residual elements.
The alloy composition of the material is designed for the following reasons:
the material design is based on Cr-Mo-V microalloyed steel, adopts low C, mn design, reduces the generation of rolling strips caused by alloy segregation, enhances the solid solution strengthening effect of Cr and Mo alloy elements, reduces the precipitation proportion, and simultaneously achieves the technical requirements of high strength and low temperature resistance by the precipitation and grain refinement effect of V (C, N), and comprises the following specific components:
c:0.18-0.22%; adopting a low-carbon design, and improving the solid solution strengthening of Mo and Cr elements on the basis of meeting the requirement of V (C, N) precipitation strengthening so as to ensure the strength and higher toughness of the steel; when the content of C is lower than 0.18%, the strength cannot be ensured, but too high content of C not only can cause segregation, but also can greatly increase the segregation of Mn and P and reduce the low-temperature impact toughness;
si:0.17 to 0.35 percent; si is an effective deoxidizer and improves tempering resistance, but Si is an element that strongly promotes graphitization and is disadvantageous to the structure in which a large amount of carbide precipitation is desired, so Si should be as small as possible;
mn:0.40 to 0.45 percent; mn improves the strength and hardenability of steel, but Mn is an element which is easy to segregate, is easy to segregate with S, P in a grain boundary, and has caused component segregation to aggravate the formation of a strip shape, so that a low Mn design is adopted, and Mn-containing alloy is not added except Mn added in the composite deoxidation of molten steel;
p is less than or equal to 0.012%; since P is a key element causing cold embrittlement, the content of P must be reduced as much as possible, but the invention controls the content of P to be less than 0.12% in consideration of smelting cost, and reduces the influence of P by solid solution of other alloy elements.
S is less than or equal to 0.003%; s element is liable to segregate with Mn and other grain boundaries, not only the grain boundary strength is reduced, heat embrittlement is caused in the rolling process, but also the formation of band-like segregation is promoted, so that S is reduced to below 0.003% by external refining
Cr:0.95 to 1.10 percent; in the quenching process, cr is an element for strongly preventing bainite transformation, can effectively improve the hardenability of the steel, has tempering softening resistance, and can improve the mechanical strength of the steel;
mo:0.80 to 0.88 percent; the Mo element can obviously delay ferrite transformation time, reduce critical cooling rate and improve hardenability of steel; in addition, mo can reduce the segregation of P in the grain boundary by reducing the diffusion coefficient of P; meanwhile, the low-C design is adopted, so that the solid solution strengthening of Mo is increased, and the effect of improving the strength and the toughness is achieved;
v:0.10 to 0.15 percent; a certain amount of V element is separated out in the quenching and tempering heat treatment process, so that the crystal grains of the steel are refined, and the strength and the toughness are improved; on the other hand, when the content is too high, the strength is reduced, the room-temperature impact toughness is reduced, and the fluctuation of mechanical properties is larger;
ti: less than or equal to 0.03 percent; although a small amount of titanium can be combined with nitrogen to form high-melting point particles, so that grains can be refined, ti (N, C) is regular cubes or cubes, has obvious sharp corners and non-combination interfaces, is easy to form crack sources, causes crack initiation and expansion, has a large influence on low-temperature impact toughness, and therefore, needs to reduce the Ti content in a matrix;
al:0.020-0.045%; al is a strong deoxidizer, and is easy to combine with N to form AlN, and a certain Al content is maintained, so that the combination of N and Ti is reduced.
The balance of Fe and residual elements.
When in production and preparation, the round casting blank is subjected to electric furnace steelmaking, LF+VD external refining and arc continuous casting, hot rolled into a rolled tube, and then heat treatment is carried out to meet the requirement of 1000MPa strength performance.
In the preparation process of the steel pipe, a heat treatment mode adopts a quenching and tempering treatment method, namely, high-temperature tempering is carried out after quenching, the quenching temperature is 880-900 ℃, the heat preservation is carried out for 30 minutes, the tempering temperature is 680-720 ℃, and the heat preservation is carried out for 90 minutes; the texture of the material after tempering is tempered sorbite, and the grain size is 9.0 grade or above.
The steel pipe has longitudinal impact energy at the temperature of minus 120 ℃: VL (10 x 10) is more than or equal to 80J; transverse impact energy: VT (10 x 10) is more than or equal to 60J; the yield strength of the steel pipe is 862 MPa-1034 MPa, and the tensile strength is more than or equal to 965MPa.
When the metal material is rolled and deformed, as the cast structure or the cast structure is not fully diffused and homogenized, the deformation has directionality, the structure and the performance after rolling are easy to generate anisotropy and texture, and the rolling of the pipe is expressed as band segregation or band layering, so that huge performance difference exists between the rolling direction and the vertical direction of the pipe.
The rolling ratio is defined as the deformation degree of the steel pipe in the rolling direction, and the calculation mode is that the larger the rolling ratio is, the larger the deformation of the rolling direction is. The invention mainly researches the impact toughness performance at low temperature, so the ratio of transverse impact energy to longitudinal impact energy is used as the characteristic of transverse and longitudinal direction dissimilarity, and the smaller the ratio is, the larger the transverse and longitudinal dissimilarity is. The relation between the ratio of the transverse impact power to the longitudinal impact power of the steel tube and the rolling ratio is counted and shown in figure 1, and the banded segregation is counted and shown in figure 2; it can be seen that as the rolling ratio increases from 4 to 22, the ratio of transverse to longitudinal impact energy tends to decrease significantly, but the rolling ratio reaches 12, and the transverse impact is only 0.55 in the longitudinal direction, so that the longitudinal impact energy at-120 ℃ is as follows: VL (10 x 10) is more than or equal to 80J; -120 ℃ transverse impact energy: VT (10 x 10) is more than or equal to 60J, the rolling ratio is not too large and is controlled within 9. Meanwhile, if the rolling ratio is too small (less than or equal to 5), the deformation of the as-cast structure is insufficient, the structure inheritance, alloy segregation, coarse grains and the like exist in the as-rolled structure, after tempering heat treatment, the added alloy cannot achieve the expected purposes of solid solution strengthening, precipitation strengthening and grain refinement, the impact performance is also low, and the low temperature resistance is affected.
Therefore, the optimal rolling ratio is 5 to 9.
Example 2
The concrete conditions of the steel pipe produced in this example are as follows:
1.1 Steel grade composition (mass percent)
TABLE 1
| C | Si | Mn | P | S | Ni | Cr | Mo | Cu | Al | Ca | V |
| 0.18 | 0.26 | 0.43 | 0.006 | 0.002 | 0.04 | 1.02 | 0.80 | 0.07 | 0.025 | 0.0009 | 0.10 |
Smelting steel by adopting an electric arc furnace, refining outside an LF+VD furnace, and producing a circular casting blank with the diameter of 150mm by using an arc continuous casting machine.
The rolling process comprises the steps of heating and homogenizing in an annular furnace at 1280 ℃, and rolling by a cross rolling perforation, a PQF three-roller continuous rolling mill and a 14-frame high-precision sizing mill to reduce the diameter to form a steel pipe with the finished product specification outer diameter of 114.3 and the wall thickness of 8.31; the rolling ratio was 6.39.
The heat treatment system is that the temperature is kept at 900 ℃ for 30 minutes, quenched by water and tempered at 690 ℃ for 90 minutes, and the actual properties are obtained as shown in the following table 2:
TABLE 2 mechanical Properties
The steel pipes were subjected to low temperature impact experiments, the results of which are shown in Table 3 below, and the drawing was performed according to Table 3 to obtain FIGS. 3 and 4.
TABLE 3 impact Properties at different temperatures
The structure is tempered sorbite, and the grain grade is 9.5.
It can be seen that at-120 ℃, the longitudinal full-size 10x10mm impact energy is 172J, the shearing ratio is 100%, the transverse impact energy 10x7.5mm impact energy is 96J, and the shearing ratio is 100%; the longitudinal impact energy at the temperature of minus 120 ℃ is satisfied: VL (10 x 10) is more than or equal to 80J; -120 ℃ transverse impact energy: VT (10 x 10) is more than or equal to 60J.
Example 3
The steel pipe provided in this example has the following composition (mass%) in table 4:
TABLE 4 chemical compositions
| C | Si | Mn | P | S | Ni | Cr | Mo | Cu | Al | Ca | V |
| 0.22 | 0.30 | 0.45 | 0.007 | 0.002 | 0.04 | 1.02 | 0.88 | 0.07 | 0.025 | 0.0009 | 0.15 |
Smelting steel by adopting an electric arc furnace, refining outside an LF+VD furnace, and producing a round casting blank with the diameter of 210mm by using an arc continuous casting machine. The rolling process comprises the steps of heating and homogenizing in an annular furnace at 1280 ℃, and rolling by a cross rolling perforation, a PQF three-roller continuous rolling mill and a 14-frame high-precision sizing mill to reduce the diameter to form a steel pipe with the outer diameter 120.14 and the wall thickness of 11.25 of the finished product specification; the rolling ratio was 9.0.
The heat treatment system is that the temperature is kept at 900 ℃ for 30 minutes, quenched by water and tempered at 690 ℃ for 90 minutes, and the actual properties are obtained as shown in the following table 5:
TABLE 5 mechanical Properties
The steel pipes were subjected to low temperature impact experiments, the results of which are shown in Table 6 below, and the drawing was performed according to Table 6, to obtain FIGS. 5 and 6.
TABLE 6 impact Properties at different temperatures
The structure is tempered sorbite, and the grain grade is 9.5 grade; it can be seen that at-120 ℃, the full-size 10x10mm in the longitudinal direction has an impact energy of 163J, the shear ratio of 90%, the transverse impact energy 10x7.5mm has an impact energy of 93J, and the shear ratio of 90%. The longitudinal impact energy at the temperature of minus 120 ℃ is satisfied: VL (10 x 10) is more than or equal to 80J; -120 ℃ transverse impact energy: VT (10 x 10) is more than or equal to 60J.
The foregoing examples illustrate the invention in detail, but are merely preferred embodiments of the invention and are not to be construed as limiting the scope of the invention. All equivalent changes and modifications within the scope of the present invention are intended to be covered by the present invention.
Claims (6)
1. The non-nickel microalloy steel pipe resistant to the low temperature of 120 ℃ below zero in the tera-Pa level is characterized by comprising the following components in percentage by mass:
c:0.18 to 0.22 percent; si:0.17 to 0.35 percent; mn:0.40 to 0.45 percent; p is less than or equal to 0.012%; s is less than or equal to 0.003%; cr:0.95 to 1.10 percent; mo:0.80 to 0.88 percent; v:0.10 to 0.15 percent; ti is less than or equal to 0.03%; al:0.020-0.045%; the balance being iron and residual elements.
2. The giga-pascal-grade non-nickel microalloy steel tube resistant to low temperatures of-120 ℃ as recited in claim 1, wherein: in the preparation process of the steel pipe, the rolling ratio is 5-9, the rolling ratio is the deformation degree of the steel pipe along the rolling direction, and the calculation mode is the ratio of the cross section area of a casting blank to the cross section area of the steel pipe, and the larger the rolling ratio is, the larger the rolling direction deformation is.
3. The giga-pascal-grade non-nickel microalloy steel tube resistant to low temperatures of-120 ℃ as recited in claim 1, wherein: in the preparation process of the steel pipe, a heat treatment mode adopts a quenching and tempering treatment method, namely, high-temperature tempering is carried out after quenching, the quenching temperature is 880-900 ℃, the heat preservation is carried out for 30 minutes, the tempering temperature is 680-720 ℃, and the heat preservation is carried out for 90 minutes.
4. The giga-pascal-grade non-nickel microalloy steel tube resistant to low temperatures of-120 ℃ as recited in claim 1, wherein: the steel pipe has longitudinal impact energy at the temperature of minus 120 ℃: VL (10 x 10) is more than or equal to 80J; transverse impact energy: VT (10 x 10) is equal to or greater than 60J.
5. A giga-pascal-grade nickel-free microalloy steel pipe resistant to low temperature of-120 ℃ as claimed in claim 3, wherein the yield strength of the steel pipe is 862 MPa-1034 MPa, and the tensile strength is greater than or equal to 965MPa.
6. A giga-pascal-grade non-nickel microalloy steel pipe with low temperature resistance at-120 ℃ as claimed in claim 3, wherein the texture of the tempered material is tempered sorbite, and the grain size is 9.0 grade or above.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311312545.1A CN117403128A (en) | 2023-10-11 | 2023-10-11 | Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311312545.1A CN117403128A (en) | 2023-10-11 | 2023-10-11 | Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117403128A true CN117403128A (en) | 2024-01-16 |
Family
ID=89495459
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311312545.1A Pending CN117403128A (en) | 2023-10-11 | 2023-10-11 | Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117403128A (en) |
-
2023
- 2023-10-11 CN CN202311312545.1A patent/CN117403128A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107177786B (en) | A kind of design and its manufacturing method of the high manganese cut deal of LNG storage tank | |
| CN101613828B (en) | Super-thick steel plate for low yield ratio buildings with 460 MPa grade yield strength and manufacturing method | |
| US11085098B2 (en) | Grade 550MPA high-temperature resistant pipeline steel and method of manufacturing same | |
| CN102534432A (en) | Method for manufacturing and tempering bainite wear-resistant steel and steel pipe | |
| CN104480406A (en) | Low-alloy high-strength high-toughness steel plate and manufacturing method thereof | |
| CN102560284B (en) | High-strength high-toughness X100 pipeline steel hot-rolled steel strip and manufacturing method thereof | |
| CN109023069B (en) | NbC nanoparticle reinforced X80 plastic pipe steel plate and manufacturing method thereof | |
| CN107574374A (en) | A kind of yield strength 420MPa levels rare earth Weather-resistance bridge steel plate and its production method | |
| CN102876999A (en) | Steel plate for hardening and tempering type low temperature pressure vessel and method for producing steel plate | |
| CN109136756B (en) | NbC nanoparticle reinforced X90 plastic pipe steel plate and manufacturing method thereof | |
| CN109023068B (en) | Steel plate for VC (polyvinyl chloride) nanoparticle reinforced X90 plastic pipe and manufacturing method thereof | |
| CN102373387A (en) | Steel plate for large-strain cold-bent tube and manufacturing method thereof | |
| CN101760702A (en) | High-strength anti-fatigue atmospheric corrosion resistant hot-rolled steel strip and method for producing same | |
| CA3181338A1 (en) | Economical low-yield ratio and high-strength steel and manufacturing method therefor | |
| CN113699439A (en) | Steel for low-yield-ratio ultrahigh-strength continuous oil pipe and manufacturing method thereof | |
| CN114807751B (en) | A516Gr.70 (HIC) acid-resistant pipe steel with excellent die-welding and low-temperature performances and manufacturing method thereof | |
| CN113930684B (en) | Economical aging-resistant high-strain precipitation-strengthened pipeline steel and production method thereof | |
| CN117403128A (en) | Tera-megapascal low-temperature-resistant non-nickel microalloy steel pipe with temperature of minus 120 DEG C | |
| CN112375997B (en) | Manufacturing method of X70M pipeline steel plate used under low-cost and ultralow-temperature conditions | |
| CN114086083B (en) | 1100 MPa-grade sulfur-resistant high-pressure gas cylinder steel, high-pressure gas cylinder and manufacturing method thereof | |
| CN105463317B (en) | Low yield strength ratio hot rolling pipe line steel reel or opening plate and preparation method thereof | |
| CN103276301A (en) | Low-temperature engineering steel with yield strength not lower than 550MPa and production method of engineering steel | |
| CN109161813B (en) | Low-compression-ratio pipeline steel X70 steel plate and production method thereof | |
| CN105803323A (en) | Method for producing X70 pipeline steel plate by adopting relaxation-cooling process | |
| CN102011064B (en) | Application of steel for X80 grade low-temperature pipe fitting |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |