CN116855843A - Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel - Google Patents
Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel Download PDFInfo
- Publication number
- CN116855843A CN116855843A CN202310824184.2A CN202310824184A CN116855843A CN 116855843 A CN116855843 A CN 116855843A CN 202310824184 A CN202310824184 A CN 202310824184A CN 116855843 A CN116855843 A CN 116855843A
- Authority
- CN
- China
- Prior art keywords
- steel
- molten steel
- refining
- slag
- smelting
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 119
- 239000010959 steel Substances 0.000 title claims abstract description 119
- 238000000034 method Methods 0.000 title claims abstract description 39
- 238000003723 Smelting Methods 0.000 title claims abstract description 21
- 230000007797 corrosion Effects 0.000 title claims abstract description 11
- 238000005260 corrosion Methods 0.000 title claims abstract description 11
- 239000002253 acid Substances 0.000 title claims abstract description 9
- 238000007670 refining Methods 0.000 claims abstract description 52
- 239000002893 slag Substances 0.000 claims abstract description 42
- 239000011777 magnesium Substances 0.000 claims abstract description 31
- 229910052749 magnesium Inorganic materials 0.000 claims abstract description 16
- 229910052717 sulfur Inorganic materials 0.000 claims abstract description 16
- 239000011593 sulfur Substances 0.000 claims abstract description 11
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000010079 rubber tapping Methods 0.000 claims abstract description 9
- 230000008018 melting Effects 0.000 claims abstract description 8
- 238000002844 melting Methods 0.000 claims abstract description 8
- 238000007667 floating Methods 0.000 claims abstract description 6
- 230000000694 effects Effects 0.000 claims abstract description 5
- 229910052782 aluminium Inorganic materials 0.000 claims description 23
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 20
- 229910052760 oxygen Inorganic materials 0.000 claims description 18
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 15
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims description 15
- 239000001301 oxygen Substances 0.000 claims description 15
- 238000006243 chemical reaction Methods 0.000 claims description 13
- 238000005516 engineering process Methods 0.000 claims description 13
- 229910018072 Al 2 O 3 Inorganic materials 0.000 claims description 11
- 239000002245 particle Substances 0.000 claims description 11
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 10
- 238000005275 alloying Methods 0.000 claims description 10
- 238000005266 casting Methods 0.000 claims description 10
- 238000005261 decarburization Methods 0.000 claims description 10
- 239000012535 impurity Substances 0.000 claims description 10
- 229910004261 CaF 2 Inorganic materials 0.000 claims description 6
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 6
- 229910052799 carbon Inorganic materials 0.000 claims description 6
- 239000011162 core material Substances 0.000 claims description 6
- SNAAJJQQZSMGQD-UHFFFAOYSA-N aluminum magnesium Chemical compound [Mg].[Al] SNAAJJQQZSMGQD-UHFFFAOYSA-N 0.000 claims description 5
- 229910052786 argon Inorganic materials 0.000 claims description 5
- 229910002056 binary alloy Inorganic materials 0.000 claims description 5
- 238000007664 blowing Methods 0.000 claims description 5
- 229910052791 calcium Inorganic materials 0.000 claims description 5
- 238000009749 continuous casting Methods 0.000 claims description 5
- CSJDCSCTVDEHRN-UHFFFAOYSA-N methane;molecular oxygen Chemical compound C.O=O CSJDCSCTVDEHRN-UHFFFAOYSA-N 0.000 claims description 5
- 230000004048 modification Effects 0.000 claims description 5
- 238000012986 modification Methods 0.000 claims description 5
- 238000010583 slow cooling Methods 0.000 claims description 5
- 239000000203 mixture Substances 0.000 claims description 4
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 3
- 229910052729 chemical element Inorganic materials 0.000 claims description 2
- 230000001590 oxidative effect Effects 0.000 claims 1
- 238000000746 purification Methods 0.000 claims 1
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 abstract description 8
- 238000005336 cracking Methods 0.000 abstract description 6
- 239000001257 hydrogen Substances 0.000 abstract description 6
- 229910052739 hydrogen Inorganic materials 0.000 abstract description 6
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 abstract description 5
- 238000001179 sorption measurement Methods 0.000 abstract description 4
- 125000004435 hydrogen atom Chemical group [H]* 0.000 abstract description 2
- 230000003068 static effect Effects 0.000 abstract 1
- 238000003756 stirring Methods 0.000 abstract 1
- 239000000047 product Substances 0.000 description 7
- 230000001276 controlling effect Effects 0.000 description 5
- 239000011575 calcium Substances 0.000 description 4
- 230000001737 promoting effect Effects 0.000 description 4
- 230000001105 regulatory effect Effects 0.000 description 4
- 238000007711 solidification Methods 0.000 description 4
- 230000008023 solidification Effects 0.000 description 4
- 150000003568 thioethers Chemical class 0.000 description 4
- 238000009529 body temperature measurement Methods 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 239000006185 dispersion Substances 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 230000002401 inhibitory effect Effects 0.000 description 3
- 229910052748 manganese Inorganic materials 0.000 description 3
- 239000011572 manganese Substances 0.000 description 3
- 238000005070 sampling Methods 0.000 description 3
- 229910001566 austenite Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 230000006911 nucleation Effects 0.000 description 2
- 238000010899 nucleation Methods 0.000 description 2
- 239000003208 petroleum Substances 0.000 description 2
- 229910000859 α-Fe Inorganic materials 0.000 description 2
- LRDIEHDJWYRVPT-UHFFFAOYSA-N 4-amino-5-hydroxynaphthalene-1-sulfonic acid Chemical compound C1=CC(O)=C2C(N)=CC=C(S(O)(=O)=O)C2=C1 LRDIEHDJWYRVPT-UHFFFAOYSA-N 0.000 description 1
- PWHULOQIROXLJO-UHFFFAOYSA-N Manganese Chemical compound [Mn] PWHULOQIROXLJO-UHFFFAOYSA-N 0.000 description 1
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 1
- 239000008186 active pharmaceutical agent Substances 0.000 description 1
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- XFWJKVMFIVXPKK-UHFFFAOYSA-N calcium;oxido(oxo)alumane Chemical compound [Ca+2].[O-][Al]=O.[O-][Al]=O XFWJKVMFIVXPKK-UHFFFAOYSA-N 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000004925 denaturation Methods 0.000 description 1
- 230000036425 denaturation Effects 0.000 description 1
- 238000006477 desulfuration reaction Methods 0.000 description 1
- 230000023556 desulfurization Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 150000002431 hydrogen Chemical class 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000009869 magnesium metallurgy Methods 0.000 description 1
- 231100000989 no adverse effect Toxicity 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 239000002436 steel type Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 238000009736 wetting Methods 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
- C22C38/06—Ferrous alloys, e.g. steel alloys containing aluminium
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0056—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00 using cored wires
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/0075—Treating in a ladle furnace, e.g. up-/reheating of molten steel within the ladle
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/06—Deoxidising, e.g. killing
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/064—Dephosphorising; Desulfurising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/04—Removing impurities by adding a treating agent
- C21C7/068—Decarburising
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
- C21C7/00—Treating molten ferrous alloys, e.g. steel, not covered by groups C21C1/00 - C21C5/00
- C21C7/10—Handling in a vacuum
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Mechanical Engineering (AREA)
- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention relates to the technical field of pipeline steel smelting, in particular to a smelting method for improving the purity of acid-resistant corrosion-resistant pipeline steel molten steel, which is characterized in that MgO-Al is obtained by performing magnesium metallurgical treatment on molten steel after molten steel is refined 2 O 3 MgO-based inclusions are removed by floating up under the static stirring and the calm action, so that the purity of molten steel is improved; reducing the sulfur content in the molten steel by smelting high-temperature tapping; the refining slag system with low melting point, high fluidity and low oxidability is produced in the refining process, the adsorption effect on inclusions is improved, the inclusions of oxide are modified and refined, the adsorption points of hydrogen atoms are dispersed, fine inclusions are utilized to refine grains, the expansion of microcracks is hindered, and the hydrogen induced cracking resistance of the steel for the acid-resistant corrosion-resistant pipeline is realized.
Description
Technical Field
The invention relates to the technical field of pipeline steel smelting, in particular to a smelting method for improving the purity of acid-resistant corrosion-resistant pipeline steel molten steel.
Background
With the continuous development of economy, the human dependence on energy is more and more serious, and petroleum resources are main energy which cannot be removed by human at present, wherein the proportion of crude oil transportation in petroleum natural transportation is increased increasingly, and most of steel plates with acid resistance and corrosion resistance are transported at the same time, H 2 S is one of the most corrosive harmful mediums in oil and gas, and the conveying pipeline is exposed to wet H 2 S is liable to generate H when in a fluid medium 2 S acid corrosion causes thinning of pipe wall, etching holes, even fracture and the like, and seriously affects the service life and safe operation of the pipeline. Hydrogen Induced Cracking (HIC) and Sulfide Stress Corrosion Cracking (SSCC) are H 2 S the predominant form of acid corrosion.
In order to ensure the better HIC resistance requirement of the pipeline steel, the low carbon component and the high purity of molten steel must be ensured in the smelting process, the total amount of inclusions is reduced as much as possible, and the denaturation treatment is carried out.
Disclosure of Invention
Aiming at the technical problems and overcoming the defects of the prior art, the invention provides a smelting method for improving the purity of molten steel of acid-resistant corrosion-resistant pipeline steel, wherein the molten steel comprises the following chemical elements in percentage by mass: c is less than or equal to 0.05 percent, mn: less than or equal to 1.50 percent of Al:0.02% -0.05%, O < 0.0015%, S < 0.0015%, mg:0.0010 to 0.0020 percent, less than or equal to 0.0004 percent of Ca and the balance of Fe and other unavoidable impurities; the smelting method further comprises the steps of adopting low-sulfur scrap steel in converter smelting, controlling the S content to be less than 0.005%, tapping the steel at 1670-1720 ℃, producing low-melting-point, high-fluidity and low-oxidability refining slag systems in the refining process, and carrying out magnesium metallurgical treatment after the refining treatment.
The technical scheme of the invention is as follows:
further, refining molten steel in an LF+RH mode, wherein RH is vacuum operated with a high vacuum degree of less than or equal to 3.0 mbar; oxygen is not blown in the RH refining process, natural decarburization is realized by utilizing a carbon-oxygen reaction under vacuum, and after the carbon content is reduced to the target steel grade component, the oxygen content in the molten steel is 0.03% -0.05%; after decarburization, aluminum is added for deoxidization, and the molten steel is circulated and bottom argon blowing is utilized to promote the floating removal of deoxidized products; after alloying, the molten steel is ensured to be broken to be empty after the activity oxygen of the molten steel is below 5 ppm.
Furthermore, adding a slag former in the LF refining process, controlling the S content in steel to be less than 0.0015% after finishing refining through slag steel reaction, adding aluminum particles on the slag surface in the LF refining process, and feeding aluminum wires into a ladle.
Further, after refining alloying, magnesium treatment is carried out, a magnesium-aluminum cored wire is fed into molten steel to deeply purify the molten steel and carry out modification regulation and control on inclusions in the steel; after the cored wire is fed, the Mg and Al contents in the steel satisfy the following relation: w (w) Mg Satisfy 2.2X10 -3 w Al +2.2×10 -6 To 5.7X10 -3 w Al +1.2×10 -5 Between them.
Further, the cored wire core material comprises 8% -15% of Mg,25% -40% of Al, and the balance of Fe and unavoidable impurities, wherein the Mg and the Al exist in the form of binary alloy particles, and the Fe is single iron powder.
Furthermore, the casting process adopts low superheat degree casting at 20-35 ℃ and the pulling speed is 0.5-0.8 m/min, the dynamic soft reduction technology is adopted to ensure the tissue compactness, and the slow cooling technology is adopted after continuous casting.
Further, the low melting point, high fluidity and low oxidability refining slag system is controlled according to the following range: caO:45% -55% of SiO 2 ：8％～10％，Al 2 O 3 ：20％～25％，MgO：8％～10％，MnO+FeO＜1％，CaF 2 Less than 6%, slag basicity of 5-7, and Mannesmann index of 0.25-0.35.
The beneficial effects of the invention are as follows:
(1) The invention adopts metallurgical technology to modify the inclusion, the inclusion of the magnesium core is pinned with grain boundary to inhibit the growth of austenite grains, and can also be used as heterogeneous nuclear point in the solidification process to induce the formation of needle-shaped ferrite in the grains, thereby refining the grains, inhibiting the development of microcracks and improving the hydrogen induced cracking resistance of the pipeline steel;
(2) The invention adopts a high-temperature desulfurization technology, reduces the production amount of sulfides in steel, and the actual activity product of manganese and sulfur in a liquid phase is smaller than the equilibrium activity product in the molten steel solidification process, so that sulfur is prevented from being separated out in a II-type MnS form at the final solidification stage, and the sulfides are separated out in a solid phase and are uniformly dispersed and distributed, thereby reducing the production amount of plastic sulfides in the steel, improving the morphology and distribution of the sulfides, and further reducing the risk of hydrogen induced cracking;
(3) The invention adopts magnesium metallurgy technology, and can upgrade alumina or calcium aluminate in steel into MgO.Al 2 O 3 MgO and a small amount of (Mn, mg) S, mgO.Al 2 O 3 Critical nucleation radius ratio of MgO to Al 2 O 3 Small size, high nucleation rate, and more fine dispersion of MgO-Al in molten steel 2 O 3 And interface energy of MgO and molten steel is higher than that of Al 2 O 3 The interface energy with molten steel is small, the wetting angle is also small, and the attraction force between particles is also smaller than Al 2 O 3 The method is small, is not easy to gather and grow, avoids the formation of clustered inclusions, is in finer dispersion distribution in a final product, is small in size, is generally less harmful to steel, can disperse hydrogen atom adsorption points, reduces the enrichment of local hydrogen, and avoids hydrogen induced cracking;
(4) In the refining process, the alkalinity of slag is a refining slag system with low melting point, high fluidity and low oxidability, and the range is controlled as follows: caO:45% -55% of SiO 2 ：8％～10％，Al 2 O 3 ：20％～25％，MgO：8％～10％，MnO+FeO＜1％，CaF 2 Less than 6%, wherein the slag alkalinity is between 5 and 7, the Mannesmann index is between 0.25 and 0.35, the slag has a lower melting point and high fluidity, the adsorption capacity of the slag to inclusions is improved, and the purity of molten steel is improved;
(5) MgO.Al obtained by the present invention 2 O 3 And MgO inclusion is favorable for pinning grain boundary, inhibiting growth of austenite grains, promoting generation of acicular ferrite in the solidification and cooling process, refining grain structure, and playing a role in regulating and controlling structure and inhibiting crack expansion.
Detailed Description
Example 1
In this embodiment, the contents of the main elements in the molten steel in the steel are as follows: 0.03% of C, 1.23% of Mn, and Al:0.03%, O0.009%, S:0.0011%, mg:0.0013%, 0.0002% Ca, and the balance Fe and other unavoidable impurities; the converter smelting adopts low sulfur scrap steel S of 0.003 percent, the tapping temperature is 1696 ℃, the high temperature and high alkalinity slag is adopted for tapping, and the steel has the following componentsThe original sulfur content in the molten steel is effectively reduced, good dynamic conditions are provided for refining, the refining treatment time is reduced, the molten steel is refined in an LF+RH mode, and the RH is subjected to vacuum operation in a high vacuum degree of 1.0 mbar; oxygen is not blown in the RH refining process, natural decarburization is realized by utilizing a carbon-oxygen reaction under vacuum, and after the carbon content is reduced to the target steel grade component, the oxygen content in the molten steel is 0.04%; after decarburization, aluminum is added for deoxidization, and the molten steel is circulated and 120L/min bottom argon blowing is utilized for promoting the floating removal of deoxidized products; after alloying, the components and the temperature are qualified and ensure that the molten steel is broken to be empty after the active oxygen content is below 5ppm after temperature measurement and sampling. Adding a slag former in the LF refining process to prepare proper refined white slag, enabling S in steel to be 0.0010% after refining is finished through slag steel reaction, adding aluminum particles on the slag surface in the LF refining process, and carrying out composite deoxidation in a steel ladle by adopting feeding aluminum wires. After refining alloying, magnesium treatment is carried out, a magnesium-aluminum cored wire is fed into molten steel to deeply purify the molten steel and carry out modification regulation and control on inclusions in the steel; after the cored wire is fed, the Mg and Al contents in the steel satisfy the following relation: w (w) Mg Satisfy 2.2X10 -3 w Al +2.2×10 -6 To 5.7X10 -3 w Al +1.2×10 -5 Between them.
The casting process adopts low superheat degree casting at 30 ℃ and the pulling speed is 0.65m/min, adopts dynamic soft reduction technology to ensure tissue compactness, and adopts slow cooling technology after continuous casting. The cored wire core material comprises 13% of Mg,26% of Al, and the balance of Fe and unavoidable impurities, wherein the Mg and the Al exist in the form of binary alloy particles, and the Fe is single iron powder. The low melting point, high fluidity and low oxidability refining slag system is controlled according to the following range: caO:51, siO 2 ：9％，Al 2 O 3 ：23％，MgO：9％，MnO+FeO:0.3％，CaF 2 0.06 percent, 5.7 percent of slag alkalinity and 0.30 percent of Mannesmann index, and purifying molten steel and regulating and controlling the composition of inclusions through slag steel reaction.
Example 2
In this embodiment, the contents of the main elements in the molten steel in the steel are as follows: c0.02%, mn:1.15%, al:0.03%, 0.0010% O, 0.0010% S, and Mg:0.0015%, 0.0002% Ca, and the balance Fe and other unavoidable impurities; converter smeltingThe low-sulfur scrap steel S is adopted for refining, the tapping temperature is 1696 ℃, the high-temperature and high-alkalinity slag is adopted for tapping, the original sulfur content in molten steel is effectively reduced, good dynamic conditions are provided for refining, the refining treatment time is reduced, the molten steel refining is carried out in an LF+RH mode, and the RH is carried out in a vacuum operation with a high vacuum degree of 1.0 mbar; oxygen is not blown in the RH refining process, natural decarburization is realized by utilizing a carbon-oxygen reaction under vacuum, and after the carbon content is reduced to the target steel grade component, the oxygen content in the molten steel is 0.04%; after decarburization, aluminum is added for deoxidization, and the molten steel is circulated and 120L/min bottom argon blowing is utilized for promoting the floating removal of deoxidized products; after alloying, the components and the temperature are qualified and ensure that the molten steel is broken to be empty after the active oxygen content is below 5ppm after temperature measurement and sampling. Adding a slag former in the LF refining process to prepare proper refined white slag, enabling S in steel to be 0.0010% after refining is finished through slag steel reaction, adding aluminum particles on the slag surface in the LF refining process, and carrying out composite deoxidation in a steel ladle by adopting feeding aluminum wires. After refining alloying, magnesium treatment is carried out, a magnesium-aluminum cored wire is fed into molten steel to deeply purify the molten steel and carry out modification regulation and control on inclusions in the steel; after the cored wire is fed, the Mg and Al contents in the steel satisfy the following relation: w (w) Mg Satisfy 2.2X10 -3 w Al +2.2×10 -6 To 5.7X10 -3 w Al +1.2×10 -5 Between them.
The casting process adopts low superheat degree casting at 30 ℃ and the pulling speed is 0.65m/min, adopts dynamic soft reduction technology to ensure tissue compactness, and adopts slow cooling technology after continuous casting. The cored wire core material comprises 13% of Mg,26% of Al, and the balance of Fe and unavoidable impurities, wherein the Mg and the Al exist in the form of binary alloy particles, and the Fe is single iron powder. The low melting point, high fluidity and low oxidability refining slag system is controlled according to the following range: caO:51, siO 2 ：9％，Al 2 O 3 ：23％，Mg：O：9％，MnO+FeO:0.3％，CaF 2 0.06 percent, slag alkalinity of 61 and Mannesmann index of 0.27, purifying molten steel through slag steel reaction and regulating and controlling inclusion composition.
Example 3
In this embodiment, the contents of the main elements in the molten steel in the steel are as follows: c0.03%, mn:1.43%, al:0.03 percent of O0.0009 percent0.0012% of S, mg:0.0017%, 0.0002% Ca, and the balance Fe and other unavoidable impurities; the converter smelting adopts low sulfur scrap steel S of 0.003 percent, the tapping temperature is 1696 ℃, high-temperature and high-alkalinity slag is adopted for tapping, the original sulfur content in molten steel is effectively reduced, good dynamic conditions are provided for refining, the refining treatment time is reduced, the molten steel refining is carried out in an LF+RH mode, and the RH is carried out in a vacuum operation with a high vacuum degree of 1.0 mbar; oxygen is not blown in the RH refining process, natural decarburization is realized by utilizing a carbon-oxygen reaction under vacuum, and after the carbon content is reduced to the target steel grade component, the oxygen content in the molten steel is 0.04%; after decarburization, aluminum is added for deoxidization, and the molten steel is circulated and 120L/min bottom argon blowing is utilized for promoting the floating removal of deoxidized products; after alloying, the components and the temperature are qualified and ensure that the molten steel is broken to be empty after the active oxygen content is below 5ppm after temperature measurement and sampling. Adding a slag former in the LF refining process to prepare proper refined white slag, enabling S in steel to be 0.0010% after refining is finished through slag steel reaction, adding aluminum particles on the slag surface in the LF refining process, and carrying out composite deoxidation in a steel ladle by adopting feeding aluminum wires. After refining alloying, magnesium treatment is carried out, a magnesium-aluminum cored wire is fed into molten steel to deeply purify the molten steel and carry out modification regulation and control on inclusions in the steel; after the cored wire is fed, the Mg and Al contents in the steel satisfy the following relation: w (w) Mg Satisfy 2.2X10 -3 w Al +2.2×10 -6 To 5.7X10 -3 w Al +1.2×10 -5 Between them.
The casting process adopts low superheat degree casting at 30 ℃ and the pulling speed is 0.65m/min, adopts dynamic soft reduction technology to ensure tissue compactness, and adopts slow cooling technology after continuous casting. The cored wire core material comprises 13% of Mg,26% of Al, and the balance of Fe and unavoidable impurities, wherein the Mg and the Al exist in the form of binary alloy particles, and the Fe is single iron powder. The low melting point, high fluidity and low oxidability refining slag system is controlled according to the following range: caO:51, siO 2 ：9％，Al 2 O 3 ：23％，Mg：0.0019％，MnO+FeO:0.3％，CaF 2 0.06 percent, slag alkalinity of 5.9 and Mannesmann index of 0.33, purifying molten steel through slag steel reaction and regulating inclusion composition.
Table 1 various inclusion detection contents (percentage) of each example
| Examples | Class A | Class B | Class C | Class D | DS class |
| 1 | 0.5 | 0.5 | 0 | 0.5 | 0 |
| 2 | 0 | 0 | 0 | 0.5 | 0 |
| 3 | 0.5 | 0.5 | 0 | 0 | 0 |
As can be seen from the combination of Table 1, the purity of the molten steel is obviously improved by improving the process, the class B inclusion has a fine grading inclusion structure, the dispersion distribution of the steel types has no adverse effect on the molten steel, the grain size of the structure can be improved to a certain extent, the strength of the steel plate is improved, and the quality of products is improved.
In addition to the embodiments described above, other embodiments of the invention are possible. All technical schemes formed by equivalent substitution or equivalent transformation fall within the protection scope of the invention.
Claims (7)
1. A smelting method for improving the purity of molten steel of acid-resistant corrosion-resistant pipeline steel is characterized by comprising the following chemical elements in percentage by mass: c is less than or equal to 0.05 percent, mn: less than or equal to 1.50 percent of Al:0.02% -0.05%, O < 0.0015%, S < 0.0015%, mg:0.0010 to 0.0020 percent, less than or equal to 0.0004 percent of Ca and the balance of Fe and other unavoidable impurities; the smelting method further comprises the steps of adopting low-sulfur scrap steel in converter smelting, controlling the S content to be less than 0.005%, tapping the steel at 1670-1720 ℃, producing low-melting-point, high-fluidity and low-oxidability refining slag systems in the refining process, and carrying out magnesium metallurgical treatment after the refining treatment.
2. The smelting method according to claim 1, wherein the molten steel is refined by LF+RH, and RH is vacuum-operated by high vacuum degree of 3.0mbar or less; oxygen is not blown in the RH refining process, natural decarburization is realized by utilizing a carbon-oxygen reaction under vacuum, and after the carbon content is reduced to the target steel grade component, the oxygen content in the molten steel is 0.03% -0.05%; after decarburization, aluminum is added for deoxidization, and the molten steel is circulated and bottom argon blowing is utilized to promote the floating removal of deoxidized products; after alloying, the molten steel is ensured to be broken to be empty after the activity oxygen of the molten steel is below 5 ppm.
3. The smelting method according to claim 2, wherein a slag former is added in the LF refining process, the S content in steel is controlled to be less than 0.0015% after refining is finished through slag steel reaction, aluminum particles are added on the slag surface in the LF refining process, and aluminum wires are fed into the ladle.
4. The smelting method according to claim 3, wherein the magnesium treatment is performed after the refining alloying, the molten steel is fed with a magnesium-aluminum cored wire to perform deep purification on the molten steel and perform modification regulation on inclusions in the steel; after the cored wire is fed, the Mg and Al contents in the steel satisfy the following relation: w (w) Mg Satisfy 2.2X10 -3 w Al +2.2×10 -6 To 5.7X10 -3 w Al +1.2×10 -5 Between them.
5. The method according to claim 4, wherein the core material composition of the core-spun core is 8% -15% of Mg,25% -40% of Al, and the balance of Fe and unavoidable impurities, wherein the Mg and the Al are both in the form of binary alloy particles, and the Fe is single iron powder.
6. The smelting method according to claim 1, wherein the casting process adopts low superheat degree casting at 20-35 ℃, the pulling speed is 0.5-0.8 m/min, the dynamic soft reduction technology is adopted to ensure tissue compactness, and the slow cooling technology is adopted after continuous casting.
7. The smelting process according to claim 1, wherein the low melting, high fluidity, low oxidizing refining slag system is controlled in the following ranges: caO:45% -55% of SiO 2 ：8％～10％，Al 2 O 3 ：20％～25％，MgO：8％～10％，MnO+FeO＜1％，CaF 2 Less than 6%, slag basicity of 5-7, and Mannesmann index of 0.25-0.35.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310824184.2A CN116855843A (en) | 2023-07-06 | 2023-07-06 | Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310824184.2A CN116855843A (en) | 2023-07-06 | 2023-07-06 | Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116855843A true CN116855843A (en) | 2023-10-10 |
Family
ID=88226316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310824184.2A Pending CN116855843A (en) | 2023-07-06 | 2023-07-06 | Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116855843A (en) |
-
2023
- 2023-07-06 CN CN202310824184.2A patent/CN116855843A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN112195314B (en) | Method for controlling inclusions in low-sulfur steel of medium plate and application | |
| CN114574770B (en) | Preparation method of high-strength fatigue-resistant 60Si2MnA spring steel | |
| CN114672728B (en) | Rare earth-containing corrosion-resistant steel and method for controlling content and existing form of rare earth | |
| CN113088624A (en) | Preparation method of low-inclusion aluminum killed steel | |
| CN113774180A (en) | Control method for oxide inclusions of high-silicon series spring steel | |
| CN114672729B (en) | Corrosion-resistant steel containing high rare earth cerium content and refining control method thereof | |
| CN111455138A (en) | Smelting method of medium-high carbon sulfur-lead composite free-cutting structural steel | |
| CN110004271B (en) | Production process for controlling B-type inclusions in pipeline steel | |
| CN115404393A (en) | Production method of rare earth Ce treated 16MnHIC steel blank for flange | |
| CN113528748B (en) | Method for controlling fine inclusions in ultra-low sulfur steel | |
| CN113293253B (en) | Method for producing high-cleanliness heat-system variety steel at low cost | |
| CN112961960B (en) | Process method for improving abnormal condition of slag discharge during tapping | |
| CN108611462B (en) | Method for controlling inclusions in ultra-low carbon steel | |
| CN113512618A (en) | Refining duplex method for effectively controlling inclusions | |
| CN115026252B (en) | Inclusion control method of EA1N steel for railway axle | |
| CN116855843A (en) | Smelting method for improving purity of molten steel of acid-resistant corrosion-resistant pipeline steel | |
| CN111112594B (en) | Stopper rod for pouring low-carbon low-alloy steel and steelmaking process using stopper rod | |
| CN114214481A (en) | Method for reducing nitrogen content in steel | |
| CN112430773A (en) | Preparation method and application of steel for battery case | |
| CN113430448A (en) | Method for preparing low-sulfur low-nitrogen low-hydrogen steel at low cost and product thereof | |
| JPH06207212A (en) | Production of high creanliness extra-low carbon steel of extremely low s | |
| CN111575441A (en) | Method for modifying deoxidation products in steel by using furnace slag | |
| CN116574965B (en) | Method for improving inclusion level of wind power steel | |
| CN116837164A (en) | Method for regulating and controlling hydrogen induced cracking resistant container steel inclusion | |
| CN117305535A (en) | Method for regulating and controlling impurities in hydrogen induced cracking resistant pipeline steel |
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 |