CN113151633A - Smelting method of ultra-low phosphorus steel - Google Patents
Smelting method of ultra-low phosphorus steel Download PDFInfo
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- CN113151633A CN113151633A CN202110258685.XA CN202110258685A CN113151633A CN 113151633 A CN113151633 A CN 113151633A CN 202110258685 A CN202110258685 A CN 202110258685A CN 113151633 A CN113151633 A CN 113151633A
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- 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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/30—Regulating or controlling the blowing
- C21C5/34—Blowing through the bath
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- 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
- C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
- C21C5/28—Manufacture of steel in the converter
- C21C5/36—Processes yielding slags of special composition
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- 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
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- 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
Abstract
The invention belongs to the technical field of converter steelmaking, and particularly relates to a smelting method of ultra-low phosphorus steel, which comprises the steps of obtaining molten steel at a converter blowing terminal point; blowing molten steel to the converter at the end point of blowing at a speed of not less than 0.1Nm3Argon is blown at the bottom at the flow rate of/min/t and stirred for 3-5min to remove phosphorus, and dephosphorized molten steel is obtained; and adding dolomite to the surface of the dephosphorized molten steel, modifying the slag, stopping the slag, and tapping to obtain the extremely-low-phosphorus molten steel. By adopting the method, the P content in the ultra-low phosphorus steel is 0.0025-0.0037% when the tapping of the converter is finished, the P content in the subsequent refining process is not more than 0.0005%, the P mass fraction in the smelted final finished product is 0.0030-0.0041%, and the P content is low.
Description
Technical Field
The invention belongs to the technical field of converter steelmaking, and particularly relates to a smelting method of ultra-low phosphorus steel.
Background
The phosphorus element content in the ultra-low phosphorus steel is less than or equal to 0.0050 percent, and the phosphorus element makes the steel become brittle at low temperature, so that the cold crack sensitivity, namely cold brittleness, is improved, and therefore, a strict requirement is provided for the P content in the molten steel in a working environment with high requirements on cold brittleness. For example, 9Ni steel series for producing a liquefied natural gas low-temperature (-196 ℃) storage tank is required to contain P element in an amount of 0.0050% by mass or less.
At present, converter smelting of ultra-low phosphorus steel mainly adopts the following operations that (1) high-alkalinity (R is 3.5-4.0) and high FeO (FeO mass fraction is more than 20%) slag is adopted to dephosphorize in the converter blowing process, and the lowest phosphorus content at the blowing end point is 0.0080%; (2) in the tapping process, non-deoxidization tapping is adopted, namely reductive alloys such as Si, Mn and Al are not added in the tapping process to keep the oxygen potential of molten steel high, slag and the like added in the tapping process cause the temperature of the molten steel to be reduced, so dephosphorization can still be carried out in the tapping process, and the dephophorization amount in the step is generally 0.0040 wt%. However, the molten steel after the smelting is performed with the subsequent refining process for deoxidation, the reduction potential of the molten steel is increased to cause rephosphorization, and the rephosphorization amount is about 0.0020 percent. That is, if the P content reaches a low level of 0.0040% at the end of tapping from the converter, the prior art can control the P content of the final product to a level of 0.0060%.
Disclosure of Invention
The invention provides a smelting method of ultra-low phosphorus steel, which reduces the phosphorus content in molten steel tapped from a converter and solves the problem of high phosphorus content of finished products caused by rephosphorization after the converter taps in the prior art.
The invention provides a smelting method of ultra-low phosphorus steel, which comprises the following steps,
obtaining molten steel at the converting end point of the converter;
blowing molten steel to the converter at the end point of blowing at a speed of not less than 0.1Nm3Argon is blown at the bottom at the flow rate of/min/t and stirred for 3-5min to remove phosphorus, and dephosphorized molten steel is obtained;
and adding dolomite to the surface of the dephosphorized molten steel, modifying the slag, stopping the slag, and tapping to obtain the extremely-low-phosphorus molten steel.
Further, the flow rate of the bottom blowing is 0.1 to 0.2Nm3/min/t。
Further, the mass fraction of phosphorus in the molten steel at the blowing end point of the converter is 0.005-0.010%.
Further, the temperature of the molten steel at the blowing end point of the converter is 1635-1665 ℃.
Further, at the end point of the converter blowing, the alkalinity of the slag is 3.8-4.2.
Further, the upgraded slagIn
Wherein, WMgORepresents the mass fraction of MgO in the slag, WCaORepresents the mass fraction of CaO in the slag, WSiO2Indicating S iO in the slag2Mass fraction of (2), WMgORepresents the mass fraction of MgO in the slag.
Furthermore, the adding mass of the dolomite is 5-8kg/t molten steel.
Further, during tapping, the temperature of the molten steel is 1620-.
Further, the capacity of the converter is 100-300 t.
Further, the molten steel for obtaining the converting end point of the converter comprises,
and (3) carrying out converter blowing on the molten iron with the phosphorus mass fraction of less than or equal to 0.18% to obtain molten steel at the blowing end point of the converter.
One or more technical solutions in the embodiments of the present invention have at least the following technical effects or advantages:
the invention provides a smelting method of extremely low phosphorus steel, which creatively utilizes the operation of bottom blowing argon of a converter after the converter finishes blowing, and utilizes the dynamic condition of steel slag mixing and the cooling effect of bottom blowing gas provided by the operation to ensure that the slag has the dynamic condition and the thermodynamic condition of dephosphorization, promote the P removal reaction in a steel ladle to further approach to a thermodynamic equilibrium state, and reduce the phosphorus content of molten steel. Meanwhile, in order to avoid rephosphorization, after argon gas is blown from the bottom, the slag is modified, the fluidity of the slag is changed, and the phenomenon that the converter discharges and slags at the end point is avoided, so that the possibility of rephosphorization is reduced to the minimum. By adopting the method, the P content in the ultra-low phosphorus steel is 0.0025-0.0037% when the tapping of the converter is finished, the P content in the subsequent refining process is not more than 0.0005%, the P mass fraction in the smelted final finished product is 0.0030-0.0041%, and the P content is low.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
FIG. 1 is a process diagram of a smelting method of ultra-low phosphorus steel according to an embodiment of the invention.
Detailed Description
The present invention will be described in detail below with reference to specific embodiments and examples, and the advantages and various effects of the present invention will be more clearly apparent therefrom. It will be understood by those skilled in the art that these specific embodiments and examples are for the purpose of illustrating the invention and are not to be construed as limiting the invention.
Throughout the specification, unless otherwise specifically noted, terms used herein should be understood as having meanings as commonly used in the art. Accordingly, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. If there is a conflict, the present specification will control.
Unless otherwise specifically stated, various raw materials, reagents, instruments, equipment and the like used in the present invention are commercially available or can be prepared by existing methods.
In order to solve the technical problems, the embodiment of the invention provides the following general ideas:
the embodiment of the invention provides a smelting method of ultra-low phosphorus steel, which is combined with a figure 1 and comprises the following steps,
s1, obtaining molten steel at the converting end point of the converter;
s2, blowing the molten steel at the end point of the converter at the speed of more than or equal to 0.1Nm3Argon is blown at the bottom at the flow rate of/min/t and stirred for 3-5min to remove phosphorus, and dephosphorized molten steel is obtained;
and S3, adding dolomite to the surface of the dephosphorized molten steel, modifying the slag, stopping the slag and tapping to obtain the ultra-low phosphorus molten steel.
Molten steel in the converter reacts with the slag, and P element originally dissolved in the molten steel reacts with CaO in the slag to enter the slag, so that P removal operation is completed. The high and low P removing rate is determined by the thermodynamic condition and the kinetics of dephosphorization. The conditions favorable for removing P are low temperature, blast furnace slag alkalinity, large slag amount and the like. Due to the limitation of kinetic conditions, under the conditions of certain slag composition, certain slag amount and certain temperature, the P content in the molten steel is always higher than the equilibrium P content under the thermodynamic conditions.
In the traditional low-phosphorus steel smelting, the main reason for influencing the phosphorus content is rephosphorization in the refining process after converter tapping, which is because the traditional low-phosphorus steel can cause slag discharging of converter slag in the converter tapping process, and the slag can cause rephosphorization in the refining process. According to the thermodynamic and kinetic rules of dephosphorization, the favorable conditions of oxidative dephosphorization are lower molten steel temperature, higher alkalinity slag, larger slag amount and good kinetic mixing conditions of the slag and the molten steel. On one hand, the invention creatively proposes that the bottom-blown argon is adopted for strong stirring in the process from the oxygen blowing of the converter to the tapping of the converter, and the generated technical effects are as follows: (1) the dynamic conditions can be improved by strong bottom blowing stirring, the reaction between steel slag is promoted, and the dephosphorization capability of the slag is fully exerted; (2) the bottom blowing argon can be cooled, so that the slag has thermodynamic conditions for further dephosphorization, the dephosphorization is facilitated, and the content of P is closer to that of P under thermodynamic equilibrium conditions compared with the conventional technology; on the other hand, the invention also provides that dolomite is added for modifying the slag before the converter taps, wherein the dolomite is an ore containing calcium element and magnesium element, can increase the content of CaO and MgO in the slag, enables the converter slag to be more viscous, reduces the slag quantity, ensures the slag-stopping and tapping effect, and avoids the phosphorus-containing slag of the converter from discharging slag and generating rephosphorization in the refining process; moreover, dolomite is also decomposed to produce CO2The gas can foam the converter slag, increase the specific surface area of the slag, promote the heat dissipation and the temperature reduction of the slag, and further avoid the slag from returning to P in the refining process. By adopting the invention, under the condition of small temperature reduction, phosphorus in the molten steel of the converter is promoted to further enter the slag of the converter, and the P content in the extremely-low phosphorus steel is 0.0025-0.0037% when the tapping of the converter is finished, the P content in the steel returned in the subsequent refining process is not more than 0.0005%, and the P quality in the final finished product is smeltedThe fraction is 0.0030-0.0041%, and the content of P is low. The flow of bottom-blown argon is too small to improve the dephosphorization condition.
After the converter finishes the main P removing task, the operation of blowing argon from the bottom for 3-5min is pioneered, so that the slag and the molten steel are more fully mixed, and compared with the front oxygen blowing and C removing process, the temperature of the molten steel is reduced by 15-25 ℃ due to the input of the bottom blowing gas, so that the thermodynamic and kinetic conditions of further P removing of the converter slag are provided.
As an embodiment of the present invention, the flow rate of the bottom blowing is 0.1 to 0.2Nm3And/min/t. The control of the bottom blowing flow in the range can not only meet the good dynamic condition of steel slag mixing, but also avoid the potential safety hazard of operation and the overlarge temperature drop of molten steel caused by overlarge bottom blowing strength, and influence on the smooth production.
As an implementation mode of the embodiment of the invention, the mass fraction of phosphorus in the molten steel at the blowing end point of the converter is 0.005-0.010%.
As an implementation manner of the embodiment of the invention, the molten steel temperature at the blowing end point of the converter is 1635-1665 ℃.
As an implementation mode of the embodiment of the invention, at the smelting end point of the converter, the alkalinity of the slag is 3.8-4.2. The basicity is the binary basicity of the slag, i.e., the mass fraction of CaO and SiO in the slag2The ratio of the mass percentages of (A) to (B). The alkalinity of the slag in the converting link is controlled at a higher level of 3.8-4.2, and the good dephosphorization rate of the molten iron can be ensured.
As an embodiment of the present invention, the modified slag is
Wherein, WMgORepresents the mass fraction of MgO in the slag, WCaORepresents the mass fraction of CaO in the slag, WSiO2Indicating SiO in the slag2Mass fraction of (2), WMgORepresents the mass fraction of MgO in the slag.
MgO, CaO and SiO in slag component2The mass fraction relation of the components is to ensure that part of free powdery MgO exists in the final slag in the tapping temperature range, the MgO can better play a thick slag effect, the slag quantity is reduced in the subsequent slag stopping operation, the slag stopping tapping effect is improved, and the rephosphorization is reduced.
As an implementation mode of the embodiment of the invention, the addition mass of the dolomite is 5-8kg/t molten steel.
As an implementation mode of the embodiment of the invention, during the steel tapping, the temperature of the molten steel is 1620-1640 ℃, and the carbon oxygen product of the molten steel is 0.0012-0.0015.
The slag stopping operation in the tapping process is a conventional slag stopping ball or slag stopping sliding plate operation and the like, and the slag modification adjusts the fluidity of the slag, so the slag stopping operation in the step can effectively reduce the slag quantity.
As an implementation manner of the embodiment of the invention, the capacity of the converter is 100-300 t.
As an implementation mode of the embodiment of the invention, the molten steel for obtaining the blowing end point of the converter comprises,
and (3) carrying out converter smelting on the molten iron with the phosphorus mass fraction of less than or equal to 0.18% to obtain molten steel at the smelting end point of the converter.
The method for smelting the ultra-low phosphorus steel according to the present invention will be described in detail with reference to examples, comparative examples and experimental data.
Example 1
The embodiment 1 provides a smelting method of extremely low phosphorus steel, and the converter tonnage is 150 tons, and the method specifically comprises the following steps:
(1) carrying out converter blowing dephosphorization and decarburization on molten iron with the phosphorus content of 0.13%, controlling the binary basicity R of the slag to be 3.86, and obtaining molten steel at the blowing end point of the converter after TSO measurement; the temperature of molten steel at the blowing end point of the converter is 1639 ℃, the phosphorus content is 0.0086 percent, and the carbon content is 0.03 percent;
(2) stirring molten steel at the end point of the converter by bottom blowing argon, wherein the strong stirring time of the bottom blowing argon is 4.5min, and the strength of bottom blowing gas is 0.15Nm3Control at/min/t;
(3) after bottom blowing argon is finished, adding dolomite into the surface of the converter slag, wherein the adding amount of each ton of steel is 5.7kg, and after the dolomite is added, the mass percentages of main components in the slag meet the following table 1:
TABLE 1
| CaO/％ | SiO2/％ | MgO/％ |
| 44.245 | 11.04 | 10.981 |
(4) Slag stopping and tapping, wherein slag is added in the tapping process, the tapping temperature is 1623 ℃, the carbon-oxygen product of molten steel is 0.0014, and the phosphorus content of the molten steel is 0.0034 percent;
(5) refining and continuous casting are continuously carried out to obtain an ultra-low phosphorus steel plate blank;
and detecting the chemical composition of the extremely-low-phosphorus steel plate blank, wherein the mass fraction of P is 0.0039 percent.
Example 2
Embodiment 2 provides a smelting method of extremely low phosphorus steel, the converter tonnage is 210 tons, and the method specifically comprises the following steps:
(1) carrying out converter smelting dephosphorization and decarburization on molten iron with the phosphorus content of 0.15%, and controlling the binary basicity R of the slag to be 4.13; after TSO measurement, obtaining molten steel at the end point of the converter; the temperature of the molten steel at the end point of the converter is 1652 ℃, the phosphorus content is 0.0080 percent, and the carbon content is 0.020 percent;
(2) stirring molten steel by bottom blowing argon in a converter, wherein the strong stirring time of the bottom blowing argon is 3.5min, and the strength of the bottom blowing gas is 0.13Nm3Control at/min/t;
(3) after bottom blowing argon is finished, adding dolomite into the surface of the converter slag, wherein the adding amount of each ton of steel is 6.3kg, and after the dolomite is added, the mass percentages of main components in the slag meet the following table 2:
TABLE 2
| CaO/％ | SiO2/％ | MgO/％ |
| 42.621 | 12.408 | 13.067 |
(4) Slag stopping and tapping, wherein slag is added in the tapping process, the tapping temperature is 1638 ℃, the carbon-oxygen product of molten steel is 0.0013, and the phosphorus content of the molten steel is 0.0037%;
(6) refining and continuous casting are continuously carried out to obtain an ultra-low phosphorus steel plate blank;
and detecting the chemical composition of the extremely-low-phosphorus steel slab, wherein the mass fraction of P is 0.0041%.
Example 3
Embodiment 3 provides a smelting method of extremely low phosphorus steel, and the converter tonnage is 300 tons, which specifically comprises the following steps:
(1) carrying out converter smelting dephosphorization and decarburization on molten iron with the phosphorus content of 0.11%, and controlling the binary basicity R of slag to be 3.77; after TSO measurement, obtaining molten steel at the end point of the converter; the temperature of the molten steel at the end point of the converter is 1645 ℃, the phosphorus content is 0.0082%, and the carbon content is 0.017%;
(2) after the TSO measurement in the later stage of converting is finished, argon is blown at the bottom of the converter to stir the molten steel, and the argon is blown at the bottom to be strongStirring for 5min, with bottom blowing gas intensity of 0.13Nm3Control at/min/t;
(3) after bottom blowing argon is finished, adding dolomite into the surface of the converter slag, wherein the adding amount of each ton of steel is 7.4kg, and after the dolomite is added, the mass percentages of main components in the slag meet the following table 3:
TABLE 3
| CaO/％ | SiO2/％ | MgO/％ |
| 44.993 | 11.05 | 16.174 |
(4) Stopping slag and tapping, wherein slag charge is added in the tapping process, the tapping temperature is 1623 ℃, the carbon-oxygen product of molten steel is 0.0014, and the phosphorus content of the molten steel is 0.0028%;
(5) refining and continuous casting are continuously carried out to obtain an ultra-low phosphorus steel plate blank;
detecting the chemical components of the extremely-low-phosphorus steel plate blank, wherein the mass fraction of P is 0.0031%.
Comparative example 1
Comparative example 1 provides a method for smelting an ultra-low phosphorus steel, which is different from example 3 in that slag-stopping tapping is performed after bottom blowing is completed, the tapping temperature is 1623 ℃, and the phosphorus content of molten steel is 0.0042% by taking example 3 as a comparison. Refining and continuously casting the steel plate to obtain an ultra-low phosphorus steel plate blank; detecting the chemical components of the ultra-low phosphorus steel plate blank, wherein the mass fraction of P is 0.0053%.
Comparative example 2
Comparative example 2 provides a method for smelting ultra-low phosphorus steel, which is different from example 3 in that dolomite is directly added for modification without bottom blowing argon gas stirring for smelting molten steel in a converter, and then slag is retained for tapping, wherein example 3 is taken as a comparison. The tapping temperature is 1643 ℃, and the phosphorus content of the molten steel is 0.0052 percent. Refining and continuously casting the steel plate to obtain an ultra-low phosphorus steel plate blank; detecting the chemical components of the ultra-low phosphorus steel plate blank, wherein the mass fraction of P is 0.0072%.
TABLE 4
Table 4 shows process data of a method for producing an extremely low phosphorus steel according to examples 1 to 3 of the present invention and comparative examples 1 to 2, and it can be seen from the data in Table 4 that the method for producing an extremely low phosphorus steel according to examples 1 to 3 of the present invention has a P mass fraction of 0.0028 to 0.0037% in a molten steel at the end of tapping from a converter, a P mass fraction of 0.0039 to 0.0041% in a slab after refining and continuous casting, a phosphorus content of 0.0003 to 0.0005% in a slab, and both the phosphorus content in a slab and the phosphorus content in a refined slab are at very low levels. According to the smelting method of the ultra-low phosphorus steel provided by the comparative example 1-2, the P mass fraction in molten steel is 0.0042-0.0052% after the tapping of a converter is finished, the P mass fraction of a plate blank is 0.0053-0.0072% after refining and continuous casting, the phosphorus recovery amount is 0.0011-0.0020%, and the phosphorus content of the plate blank and the phosphorus recovery amount after refining are higher than those of the embodiment 1-3.
The invention provides a smelting method of extremely low phosphorus steel, which firstly proposes that bottom-blown argon is adopted for strong stirring in the process from the oxygen blowing of a converter to the tapping of the converter, the thermodynamic and kinetic conditions of dephosphorization are improved, and the content of P in molten steel is closer to P under the thermodynamic equilibrium condition; on the other hand, the slag modification is carried out before the converter tapping, so that the rephosphorization caused by the slag discharging during the converter tapping is avoided, and the gas generated by the decomposition of the dolomite used for modification can also promote the heat dissipation and the temperature reduction of the slag, thereby further avoiding the rephosphorization during the refining process. By adopting the method, the P content in the ultra-low phosphorus steel is 0.0025-0.0037% when the tapping of the converter is finished, the P content in the subsequent refining process is not more than 0.0005%, the P mass fraction in the smelted final finished product is 0.0030-0.0041%, and the P content is low.
Finally, it should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.
It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (10)
1. A smelting method of ultra-low phosphorus steel is characterized by comprising the following steps,
obtaining molten steel at the converting end point of the converter;
blowing molten steel to the converter at the end point of blowing at a speed of not less than 0.1Nm3Argon is blown at the bottom at the flow rate of/min/t and stirred for 3-5min to remove phosphorus, and dephosphorized molten steel is obtained;
and adding dolomite to the surface of the dephosphorized molten steel, modifying the slag, stopping the slag, and tapping to obtain the extremely-low-phosphorus molten steel.
2. The method for smelting extremely low phosphorus steel according to claim 1, wherein the flow rate of the bottom blowing is 0.1 to 0.2Nm3/min/t。
3. The method for smelting an ultra-low phosphorus steel as claimed in claim 1, wherein the mass fraction of phosphorus in the molten steel at the blowing end point of the converter is 0.005-0.010%.
4. The method for smelting extremely low phosphorus steel as claimed in claim 1, wherein the temperature of the molten steel at the blowing end point of the converter is 1635-1665 ℃.
5. The method for smelting extremely low phosphorus steel according to claim 1, wherein the basicity of the slag at the end of the converter blowing is 3.8 to 4.2.
6. The method of claim 1, wherein the upgraded slag is a steel having very low phosphorous content
Wherein, WMgORepresents the mass fraction of MgO in the slag, WCaORepresents the mass fraction of CaO in the slag, WSiO2Indicating SiO in the slag2Mass fraction of (2), WMgORepresents the mass fraction of MgO in the slag.
7. The method for smelting extremely low phosphorous steel as claimed in claim 1, wherein the mass of the added dolomite is 5-8kg/t molten steel.
8. The method for smelting extremely low phosphorus steel as claimed in claim 1, wherein the temperature of molten steel is 1620 ℃ and 1640 ℃, and the carbon oxygen product of molten steel is 0.0012-0.0015 during tapping.
9. The method for smelting extremely low phosphorus steel as claimed in claim 1, wherein the capacity of the converter is 100-300 t.
10. The method for smelting an ultra-low phosphorus steel as claimed in claim 1, wherein said obtaining molten steel at the blowing end of the converter comprises,
and (3) carrying out converter blowing on the molten iron with the phosphorus mass fraction of less than or equal to 0.18% to obtain molten steel at the blowing end point of the converter.
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| CN114134391A (en) * | 2021-11-05 | 2022-03-04 | 内蒙古北方重工业集团有限公司 | Smelting method for controlling sulfur content of sulfur-containing low alloy steel |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6092416A (en) * | 1983-10-26 | 1985-05-24 | Nippon Steel Corp | Production of extra-low phosphorus steel |
| JP2000017315A (en) * | 1998-07-03 | 2000-01-18 | Sumitomo Metal Ind Ltd | Method for dephosphorizing molten iron |
| CN101935734A (en) * | 2010-08-23 | 2011-01-05 | 首钢总公司 | Method for reducing rephosphorization amount in convertor steelmaking process |
| CN102839251A (en) * | 2012-09-13 | 2012-12-26 | 首钢总公司 | Smelting method of low-phosphorous steel |
| CN102943145A (en) * | 2012-11-26 | 2013-02-27 | 湖南华菱湘潭钢铁有限公司 | Converter smelting method of ultra-low phosphorus steel |
| CN107354268A (en) * | 2017-08-30 | 2017-11-17 | 武汉钢铁有限公司 | The method for carrying out dephosphorization to converter tapping ladle using lime stone |
| CN107365886A (en) * | 2016-05-13 | 2017-11-21 | 上海梅山钢铁股份有限公司 | A kind of method of converter high temperature dephosphorization |
| CN108251592A (en) * | 2018-01-19 | 2018-07-06 | 山东钢铁集团日照有限公司 | A kind of converter smelting method of extremely low phosphoretic steel |
| CN108660278A (en) * | 2017-03-27 | 2018-10-16 | 宝山钢铁股份有限公司 | A kind of converter smelting method of low-phosphorous low-oxygen steel |
-
2021
- 2021-03-10 CN CN202110258685.XA patent/CN113151633A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6092416A (en) * | 1983-10-26 | 1985-05-24 | Nippon Steel Corp | Production of extra-low phosphorus steel |
| JP2000017315A (en) * | 1998-07-03 | 2000-01-18 | Sumitomo Metal Ind Ltd | Method for dephosphorizing molten iron |
| CN101935734A (en) * | 2010-08-23 | 2011-01-05 | 首钢总公司 | Method for reducing rephosphorization amount in convertor steelmaking process |
| CN102839251A (en) * | 2012-09-13 | 2012-12-26 | 首钢总公司 | Smelting method of low-phosphorous steel |
| CN102943145A (en) * | 2012-11-26 | 2013-02-27 | 湖南华菱湘潭钢铁有限公司 | Converter smelting method of ultra-low phosphorus steel |
| CN107365886A (en) * | 2016-05-13 | 2017-11-21 | 上海梅山钢铁股份有限公司 | A kind of method of converter high temperature dephosphorization |
| CN108660278A (en) * | 2017-03-27 | 2018-10-16 | 宝山钢铁股份有限公司 | A kind of converter smelting method of low-phosphorous low-oxygen steel |
| CN107354268A (en) * | 2017-08-30 | 2017-11-17 | 武汉钢铁有限公司 | The method for carrying out dephosphorization to converter tapping ladle using lime stone |
| CN108251592A (en) * | 2018-01-19 | 2018-07-06 | 山东钢铁集团日照有限公司 | A kind of converter smelting method of extremely low phosphoretic steel |
Non-Patent Citations (1)
| Title |
|---|
| 蔡开科: "《连铸坯质量控制》", 31 May 2010, 北京：冶金工业出版社 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114134391A (en) * | 2021-11-05 | 2022-03-04 | 内蒙古北方重工业集团有限公司 | Smelting method for controlling sulfur content of sulfur-containing low alloy steel |
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