CN114317865A - Method for controlling carbon-oxygen reaction of vacuum treatment of aluminum-free bearing steel - Google Patents
Method for controlling carbon-oxygen reaction of vacuum treatment of aluminum-free bearing steel Download PDFInfo
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- CN114317865A CN114317865A CN202210110423.3A CN202210110423A CN114317865A CN 114317865 A CN114317865 A CN 114317865A CN 202210110423 A CN202210110423 A CN 202210110423A CN 114317865 A CN114317865 A CN 114317865A
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- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 94
- 239000010959 steel Substances 0.000 title claims abstract description 94
- 238000000034 method Methods 0.000 title claims abstract description 34
- 238000006243 chemical reaction Methods 0.000 title claims abstract description 26
- 238000009489 vacuum treatment Methods 0.000 title claims abstract description 25
- CSJDCSCTVDEHRN-UHFFFAOYSA-N methane;molecular oxygen Chemical compound C.O=O CSJDCSCTVDEHRN-UHFFFAOYSA-N 0.000 title claims abstract description 23
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 41
- 239000001301 oxygen Substances 0.000 claims abstract description 41
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 38
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims abstract description 25
- 229910052799 carbon Inorganic materials 0.000 claims abstract description 25
- 239000002893 slag Substances 0.000 claims abstract description 23
- 238000007670 refining Methods 0.000 claims abstract description 19
- 238000010079 rubber tapping Methods 0.000 claims abstract description 17
- 238000003723 Smelting Methods 0.000 claims abstract description 8
- HBMJWWWQQXIZIP-UHFFFAOYSA-N silicon carbide Chemical compound [Si+]#[C-] HBMJWWWQQXIZIP-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910010271 silicon carbide Inorganic materials 0.000 claims abstract description 8
- 238000005406 washing Methods 0.000 claims abstract description 8
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 14
- 229910052782 aluminium Inorganic materials 0.000 claims description 10
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 7
- 229910052742 iron Inorganic materials 0.000 claims description 7
- 239000010936 titanium Substances 0.000 claims description 6
- 229910052719 titanium Inorganic materials 0.000 claims description 6
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 16
- 230000031877 prophase Effects 0.000 abstract description 3
- 238000005272 metallurgy Methods 0.000 abstract description 2
- 239000006004 Quartz sand Substances 0.000 abstract 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 abstract 1
- 230000002035 prolonged effect Effects 0.000 abstract 1
- 238000005728 strengthening Methods 0.000 abstract 1
- 238000005266 casting Methods 0.000 description 6
- 239000000956 alloy Substances 0.000 description 5
- 229910045601 alloy Inorganic materials 0.000 description 5
- 238000009749 continuous casting Methods 0.000 description 5
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 4
- 238000005261 decarburization Methods 0.000 description 4
- 230000014759 maintenance of location Effects 0.000 description 4
- 229910052710 silicon Inorganic materials 0.000 description 4
- 239000010703 silicon Substances 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 3
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 2
- 238000007664 blowing Methods 0.000 description 2
- 229910002091 carbon monoxide Inorganic materials 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 230000005856 abnormality Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000011819 refractory material Substances 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
Classifications
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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
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- Treatment Of Steel In Its Molten State (AREA)
Abstract
The invention relates to the technical field of metallurgy, in particular to a carbon-oxygen reaction control method for vacuum treatment of aluminum-free bearing steel, which comprises the following specific steps: (1) in the primary smelting process, the final oxygen content and the target carbon content need to be controlled, the tapping operation is strengthened, and sliding plates are used for pushing off slag during tapping; (2) washing the steel ladle; (3) refining: the alkalinity of the slag is controlled in the early stage of refining, and quartz sand is added in the later stage of refining to reduce the alkalinity of the slag; (4) strengthening the deoxidation of the LF refining slag surface, using high-purity high-density silicon carbide to perform deoxidation operation, and controlling the oxygen content before vacuum treatment to be less than or equal to 15 ppm; (5) a prophase vacuum groove is adopted, and residual steel residues in a vacuum chamber are cleaned before production; (6) the vacuum treatment time is prolonged, the vacuum degree is improved to be below 67pa, high vacuum pressure maintaining is realized, the oxygen content in the bearing steel production process can be reduced, the carbon-oxygen reaction balance can be maintained, the stability of a vacuum chamber is improved, and the occurrence of accidental production accidents is reduced.
Description
Technical Field
The invention relates to the technical field of metallurgy, in particular to a carbon-oxygen reaction control method for vacuum treatment of aluminum-free bearing steel.
Background
The production of the aluminum-free bearing steel is characterized in that the aluminum content of molten steel is controlled to be less than or equal to 15ppm, and the aluminum content is strictly controlled by the used alloy auxiliary materials and refractory materials contacting with the molten steel, so that the inclusion is low-melting-point plastic inclusion, the castability of the molten steel is strong, and the influence of the inclusion on the fatigue life of steel is lower than that of high-melting-point non-deformable inclusion. However, in the production process, carbon and oxygen reactions are severe in the vacuum treatment process due to the high carbon content of the molten steel, the molten steel is splashed to the upper groove and the top lance, the concentration of carbon monoxide is continuously increased, the carbon content and oxygen content of the molten steel exceed the process requirements, secondary treatment is forced, and the continuous casting machine is likely to stop casting production. Therefore, the carbon-oxygen reaction in the vacuum treatment process must be controlled to ensure that the carbon and oxygen components meet the technological requirements of the aluminum-free bearing steel.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: in order to solve the problems that in the production process in the prior art, carbon-oxygen reaction is violent in the vacuum treatment process due to high carbon content of molten steel, the molten steel is splashed to an upper groove and a top gun, the concentration of carbon monoxide is continuously increased, the carbon content and the oxygen content of the molten steel exceed the process requirements, secondary treatment is forced, and casting stop production of a continuous casting machine can be possibly caused, the method for controlling the carbon-oxygen reaction in the vacuum treatment of the aluminum-free bearing steel is provided.
The technical scheme adopted by the invention for solving the technical problems is as follows: a carbon-oxygen reaction control method for vacuum treatment of aluminum-free bearing steel is characterized by comprising the following specific steps:
(1) in the primary smelting process, the final oxygen content and the target carbon content need to be controlled, the tapping operation is strengthened, and sliding plates are used for pushing off slag during tapping;
(2) washing the steel ladle, wherein the steel ladle does not need to be smelted in the early stage of the steel ladle, and steel grades containing harmful elements such as high oxygen, aluminum, titanium and the like are not smelted;
(3) in the LF process, low-alkalinity refining slag is adopted, and high-purity silicon carbide (SiC is more than or equal to 90%) is used for deoxidizing the slag surface;
(4) after refining, the Si content of the molten steel is increased to 0.30-0.35% so as to ensure that the dissolved oxygen of the molten steel is controlled within 15 ppm;
(5) RH adopts a front-stage vacuum tank, and RH high vacuum (<67Pa) time is 25-30 min to control the total oxygen content of the molten steel.
Further comprises the following components: 0.95-1.05% of C, 0.30-0.35% of Si, 0.25-0.40% of Mn, 0.020% of P, 0.015% of S, 0.0015% of Al, 1.40-1.60% of Cr and the balance of iron and residual elements.
Further comprising the step (1) of controlling the carbon content of the molten steel at the end point to be 0.15% or more and reducing the oxygen content of the steel to be 200ppm or less.
Further comprising the step (3) of controlling the alkalinity of the refining slag in the LF refining process to be 0.80-1.20.
Further includes that the RH vacuum tank is not used for producing the aluminum-free bearing steel after being used for more than 50 furnaces.
The invention has the beneficial effects that: the invention provides a method for controlling carbon-oxygen reaction in vacuum treatment of aluminum-free bearing steel, which reduces the oxygen content of tapping steel by controlling the end point carbon content and controls the alkalinity of slag so as to control the oxygen content of the slag and control the high vacuum pressure maintaining time,
1. the quality accident caused by high oxygen content of the aluminum-free bearing steel in the production process is solved, and the oxygen content in the bearing steel production process can be reduced;
2. the problem of abnormal components caused by easy carbon-oxygen reaction in the vacuum process of the aluminum-free bearing steel with low aluminum content is solved, and the carbon-oxygen reaction balance can be maintained;
3. the problem of serious shaking of the vacuum chamber in the vacuum process under the condition of low aluminum content of the aluminum-free bearing steel is solved, and the stability of the vacuum chamber is improved;
4. the problem of possible production interruption accidents is solved, and the occurrence of accidental production accidents is reduced.
Detailed Description
A carbon-oxygen reaction control method for vacuum treatment of aluminum-free bearing steel is characterized by comprising the following specific steps:
(1) in the primary smelting process, the final oxygen content and the target carbon content need to be controlled, the tapping operation is strengthened, and sliding plates are used for pushing off slag during tapping;
(2) washing the steel ladle, wherein the steel ladle does not need to be smelted in the early stage of the steel ladle, and steel grades containing harmful elements such as high oxygen, aluminum, titanium and the like are not smelted;
(3) in the LF process, low-alkalinity refining slag is adopted, and high-purity silicon carbide (SiC is more than or equal to 90%) is used for deoxidizing the slag surface;
(4) after refining, the Si content of the molten steel is increased to 0.30-0.35% so as to ensure that the dissolved oxygen of the molten steel is controlled within 15 ppm;
(5) and RH adopts a front-stage vacuum tank, and RH high vacuum (<67Pa) time is 25-30 min to control the total oxygen content of the molten steel, so that the purity of the molten steel can meet the requirement of bearing steel.
The bearing steel comprises the following components: 0.95-1.05% of C, 0.30-0.35% of Si, 0.25-0.40% of Mn, 0.020% of P, 0.015% of S, 0.0015% of Al, 1.40-1.60% of Cr and the balance of iron and residual elements.
In the step (1), the carbon content of the molten steel at the end point is controlled to be more than 0.15%, and the oxygen content of the steel is further reduced to be less than 200 ppm.
And (4) controlling the alkalinity of the refining slag to be 0.80-1.20 in the LF refining process in the step (3) so as to solve the problem of the castability of the bearing steel molten steel.
When the RH vacuum tank is used in excess of 50 furnaces, it is no longer used to produce aluminum-free bearing steel.
The oxygen content of the aluminum-free bearing steel produced by the method can be controlled to be 5-10 ppm, the average value of the total oxygen is 6.5ppm, and ten thousand tons of aluminum-free bearing steel is produced without component abnormality and production interruption accidents caused by violent carbon-oxygen reaction.
The present invention will be described in detail with reference to examples, but the present invention is not limited to these examples.
Example 1:
(1) carrying out decarburization, dephosphorization, carbon retention and temperature rise on scrap steel and desulfurized molten iron in a primary smelting furnace, and then tapping, wherein the target carbon content is controlled to be 0.16%, and the tapping oxygen content is 180 ppm;
(2) washing the ladle, wherein the steel grade produced in the early stage of the ladle is a non-high-oxygen, low-aluminum and low-titanium hard wire steel grade;
(3) the alkalinity of slag at the early stage of refining is 1.8, the content of alloy silicon element is controlled to be 0.30 percent, and the oxygen content of molten steel before vacuum treatment is 14 ppm;
(4) adopting a prophase vacuum groove, and carrying out the wire feeding for the 8 th time;
(5) vacuum treatment time is 28 min; after the air is broken, soft blowing is carried out until continuous casting and casting are carried out;
the bearing steel produced by the method produces 17 furnaces in the whole casting process, and the phenomena of abnormal components and production interruption caused by carbon-oxygen reaction are avoided.
Example 2:
1) carrying out decarburization, dephosphorization, carbon retention and temperature rise on scrap steel and desulfurized molten iron in a primary smelting furnace, and then tapping, wherein the target carbon content is controlled to be 0.18%, and the tapping oxygen content is 160 ppm;
(2) washing the ladle, wherein the steel grade produced in the early stage of the ladle is a non-high-oxygen, low-aluminum and low-titanium hard wire steel grade;
(3) the slag alkalinity at the early stage of refining is 1.9, the silicon element content of the alloy is controlled to be 0.31 percent, and the oxygen content of the molten steel before vacuum treatment is 14 ppm;
(4) adopting a prophase vacuum groove, and carrying out the line-feeding for the 23 rd time;
(5) vacuum processing for 30 min; and (4) after the air is broken, soft blowing to continuous casting and casting.
The bearing steel produced by the method produces 15 furnaces in the whole casting process, and the phenomena of abnormal components and production interruption caused by carbon-oxygen reaction are avoided.
Comparative example 1:
(1) carrying out decarburization, dephosphorization, carbon retention and temperature rise on scrap steel and desulfurized molten iron in a primary smelting furnace, and then tapping, wherein the target carbon content is controlled to be 0.08%, and the oxygen content of tapping is 459 ppm;
(2) washing the hard-wire steel ladle;
(3) normally controlling the silicon element component of the alloy to 0.22 percent, deoxidizing by using high-purity silicon carbide, and controlling the oxygen content of molten steel to be 22ppm before vacuum treatment;
(4) adopting an early-stage vacuum tank, and enabling the number of times of line feeding to be 6 th;
(5) vacuum processing time is 29 min; in the vacuum treatment process, the C-O reaction is severe, the vacuum groove shakes seriously, the C content of the molten steel is 0.88 percent after vacuum, a 1200m carbon wire is forced to be fed to adjust the C content, and then continuous casting is carried out.
Comparative example 2:
(1) carrying out decarburization, dephosphorization, carbon retention and temperature rise on scrap steel and desulfurized molten iron in a primary smelting furnace, and then tapping, wherein the target carbon content is controlled to be 0.15%, and the tapping oxygen content is 200 ppm;
(2) washing the ladle, wherein the steel grade produced in the early stage of the ladle is a non-high-oxygen, low-aluminum and low-titanium hard wire steel grade;
(3) the alkalinity of slag at the early stage of refining is 1.9, the content of alloy silicon element is controlled to be 0.30 percent, and the oxygen content of molten steel is 15ppm before vacuum treatment;
(4) a later-stage vacuum groove is adopted, the line feeding times are 70 times, and partial slag steel is remained in a vacuum chamber;
(5) vacuum processing time is 25 min; sampling and oxygen determination after air breaking.
The CO concentration in tail gas detection is over 95 percent due to violent reaction of slag steel in a vacuum chamber and carbon in molten steel, the vacuum chamber is greatly shaken due to violent carbon-oxygen reaction in the early stage of vacuum treatment, high vacuum pressure maintaining cannot be carried out, the carbon content of a sample is 0.85 percent which is lower than the requirement of 0.95 percent of steel grade after the carbon-oxygen reaction is finished after 10min and the oxygen content of the molten steel is up to 15ppm, and the smooth production is influenced by re-deoxidation and secondary treatment.
In light of the foregoing description of the preferred embodiment of the present invention, many modifications and variations will be apparent to those skilled in the art without departing from the spirit and scope of the invention. The technical scope of the present invention is not limited to the content of the specification, and must be determined according to the scope of the claims.
Claims (5)
1. A carbon-oxygen reaction control method for vacuum treatment of aluminum-free bearing steel is characterized by comprising the following specific steps:
(1) in the primary smelting process, the final oxygen content and the target carbon content need to be controlled, the tapping operation is strengthened, and sliding plates are used for pushing off slag during tapping;
(2) washing the steel ladle, wherein the steel ladle does not need to be smelted in the early stage of the steel ladle, and steel grades containing harmful elements such as high oxygen, aluminum, titanium and the like are not smelted;
(3) in the LF process, low-alkalinity refining slag is adopted, and high-purity silicon carbide (SiC is more than or equal to 90%) is used for deoxidizing the slag surface;
(4) after refining, the Si content of the molten steel is increased to 0.30-0.35% so as to ensure that the dissolved oxygen of the molten steel is controlled within 15 ppm;
(5) RH adopts a front-stage vacuum tank, and RH high vacuum (<67Pa) time is 25-30 min to control the total oxygen content of the molten steel.
2. The method for controlling the carbon-oxygen reaction in the vacuum treatment of the aluminum-free bearing steel as claimed in claim 1, wherein: the bearing steel comprises the following components: 0.95-1.05% of C, 0.30-0.35% of Si, 0.25-0.40% of Mn, 0.020% of P, 0.015% of S, 0.0015% of Al, 1.40-1.60% of Cr and the balance of iron and residual elements.
3. The method for controlling the carbon-oxygen reaction in the vacuum treatment of the aluminum-free bearing steel as claimed in claim 1, wherein: in the step (1), the carbon content of the molten steel at the end point is controlled to be more than 0.15%, and the oxygen content of the steel is further reduced to be less than 200 ppm.
4. The method for controlling the carbon-oxygen reaction in the vacuum treatment of the aluminum-free bearing steel as claimed in claim 1, wherein: and (4) controlling the alkalinity of the refining slag to be 0.80-1.20 in the LF refining process in the step (3).
5. The method for controlling the carbon-oxygen reaction in the vacuum treatment of the aluminum-free bearing steel as claimed in claim 1, wherein: when the RH vacuum tank is used in excess of 50 furnaces, it is no longer used to produce aluminum-free bearing steel.
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| CN202210110423.3A CN114317865B (en) | 2022-01-29 | 2022-01-29 | Method for controlling carbon-oxygen reaction of vacuum treatment of aluminum-free bearing steel |
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| CN202210110423.3A CN114317865B (en) | 2022-01-29 | 2022-01-29 | Method for controlling carbon-oxygen reaction of vacuum treatment of aluminum-free bearing steel |
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| CN104212935A (en) * | 2014-08-22 | 2014-12-17 | 山东西王特钢有限公司 | Method for producing high-grade GCr15 bearing steel by using high-titanium chrome iron |
| CN105463150A (en) * | 2015-12-18 | 2016-04-06 | 中天钢铁集团有限公司 | Steel smelting process used for automobile hub bearing |
| CN109055664A (en) * | 2018-10-08 | 2018-12-21 | 中天钢铁集团有限公司 | A kind of bearing steel molten steel deoxidation control method of no Ds type impurity |
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| CN109402327A (en) * | 2018-11-22 | 2019-03-01 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method of super clean high-carbon-chromium bearing steel |
| CN110846581A (en) * | 2019-12-05 | 2020-02-28 | 中天钢铁集团有限公司 | Smelting method for realizing ultrahigh purity of bearing steel by controlling alkalinity of furnace slag and combining electromagnetic stirring of tundish |
| CN110983161A (en) * | 2019-12-05 | 2020-04-10 | 中天钢铁集团有限公司 | Smelting method for realizing ultrahigh purity of bearing steel by controlling adding time of low-aluminum low-titanium ferrosilicon and combining with tundish electromagnetic stirring |
-
2022
- 2022-01-29 CN CN202210110423.3A patent/CN114317865B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104212935A (en) * | 2014-08-22 | 2014-12-17 | 山东西王特钢有限公司 | Method for producing high-grade GCr15 bearing steel by using high-titanium chrome iron |
| CN105463150A (en) * | 2015-12-18 | 2016-04-06 | 中天钢铁集团有限公司 | Steel smelting process used for automobile hub bearing |
| CN109252013A (en) * | 2018-09-28 | 2019-01-22 | 中天钢铁集团有限公司 | A kind of bearing steel slagging process control method of full plastic occluded foreignsubstance |
| CN109055664A (en) * | 2018-10-08 | 2018-12-21 | 中天钢铁集团有限公司 | A kind of bearing steel molten steel deoxidation control method of no Ds type impurity |
| CN109402327A (en) * | 2018-11-22 | 2019-03-01 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method of super clean high-carbon-chromium bearing steel |
| CN110846581A (en) * | 2019-12-05 | 2020-02-28 | 中天钢铁集团有限公司 | Smelting method for realizing ultrahigh purity of bearing steel by controlling alkalinity of furnace slag and combining electromagnetic stirring of tundish |
| CN110983161A (en) * | 2019-12-05 | 2020-04-10 | 中天钢铁集团有限公司 | Smelting method for realizing ultrahigh purity of bearing steel by controlling adding time of low-aluminum low-titanium ferrosilicon and combining with tundish electromagnetic stirring |
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