CN106435093A - Refining slag for bearing steel production and smelting process of refining slag - Google Patents
Refining slag for bearing steel production and smelting process of refining slag Download PDFInfo
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- CN106435093A CN106435093A CN201610892473.6A CN201610892473A CN106435093A CN 106435093 A CN106435093 A CN 106435093A CN 201610892473 A CN201610892473 A CN 201610892473A CN 106435093 A CN106435093 A CN 106435093A
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- slag
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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
- C21C7/076—Use of slags or fluxes as treating agents
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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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- Organic Chemistry (AREA)
- Treatment Of Steel In Its Molten State (AREA)
- Carbon Steel Or Casting Steel Manufacturing (AREA)
Abstract
The invention discloses refining slag for bearing steel production and a smelting process of the refining slag, wherein the refining slag comprises the following components in percentage by weight: less than or equal to 6% of SiO2, 40-50% of Al2O3, 45-55% of CaO, less than or equal to 8% of MgO, less than or equal to 0.05% of TiO2 and less than or equal to 2% of Fe2O3, the particle size is controlled at 3-45mm, and the alkalinity is controlled at about 10; and the smelting process comprises the main steps of predeoxidizing after converter tapping, starting to alloy at 80s after starting to tap (the tapping quantity is about 35t), adding one of aluminum iron, carbon powder, alloy and lime in sequence, impacting and smelting by using a steel flow, and then, adding the other material; adding 600Kg of the refining slag at one step after a refining furnace is seated; and adding a deoxidizer by strictly executing the principles of multiple batches and small quantity. By using the refining slag, the problem for controlling the O content as well as B, D and TiN inclusions in a bearing steel production process is simultaneously solved; and the refining slag plays a critical role in improving the quality of bearing steel.
Description
Technical field
The invention belongs to technical field of steelmaking and refining, is related to a kind of bearing steel in refining process slag making materials and its smelting
Technique.
Background technology
The working environment of bearing is sufficiently complex, therefore it is required which possesses very high intensity and abrasion resistance properties, Standard
Reach Ti content≤50ppm, O content≤12ppm, B type impurity≤2.0, D type impurity≤1.0；And some high-end customers
Requirement be even more higher than national standard, it is desirable to reach：Ti content≤15ppm, O content≤8ppm, and will to B, D type impurity
Ask and add tight 0.5 grade than GB.It is equally known that the principal element for affecting these performances is each type impurity in molten steel, control
These field trashes good are the key factors of bearing steel smelting production, are the guarantees of bearing steel quality and performance.Bearing steel smelter
Skill is molten iron pretreatment converter ladle refining furnace（LF）Vacuum drying oven（RH）Continuous casting, ladle refining furnace is pressed from both sides in control steel
Debris species, form, quantity, the critical process of size, and ladle refining furnace is mainly mingled with to control by controlling refining slag
Species and form.Prior art controls the method for steel inclusion species, form, quantity, size as follows：
Application（Patent）Number be CN201510441084.7《A kind of preparation method of Smelting Bearing Steel refining slag》It is a kind of axle
Hold the efficient desulfurization rapidly of steel refining slag, active adsorption steel inclusion, nonmetallic folder in solution traditional bearing steel production technology
Debris content height, the problems such as granule is thick, is not directed to the control of Ti content in steel, with certain limitation.
Application（Patent）Number be CN201280051082.1《Bearing steel and its manufacture method》It is to be applied for by Nippon Steel, in steel
Middle addition rare earth metal control field trash, but Ti≤50ppm in its composition, it is impossible to meet high standard bearing steel enterprise≤
The requirement of 15ppm.
Application（Patent）Number be CN201310243395.3《A kind of method for reducing Ti content during wire for steel cord of tyre is smelted》Control
System loads the molten iron of converter and Ti weight percent content≤0.03% in steel scrap and smelting process, refining process using quartz
Sand makes low alkalinity slag system control Ti content, and bearing steel production is selected for high alkalinity slag system, and adds quartz sand to field trash
Control brings adverse effect.
Ruan little Jiang etc. exists in September, 2008《Special steel》Deliver《Refining slag is to bearing oxygen content in steel and field trash
Impact》In the mainly countershaft impact for holding oxygen content in steel and field trash of refine slag ingredient experimentation, research is refine
Impact of the finishing slag basicity to oxygen content in steel and field trash, does not refer to use and the proportioning of early stage slag charge, and the finishing slag of its research
Dual alkalinity is less than 4.5, how does not refer to and rapid slagging and reduces molten steel Ti content.
Zheng Shaobo etc. is in 2005 collection of thesis of in May, 2005 Special Steel in China annual meeting《Ti content in high-carbon-chromium bearing steel
Control》Adopt silicomanganese pre-deoxidation, hyperoxia position add ferrochrome and low alkalinity refining slag can by Ti control in bearing steel to 15ppm with
Under, but O content controls in 10ppm or so, does not reach≤8ppm requirement, and the slag system is low alkalinity slag system, and the present invention is adopted
It is high alkalinity slag system, Ti content can be solved the problems, such as, oxygen content can be reduced again to greatest extent.
In sum, it has not been found that can be by the control of Ti content in≤15ppm, while O content control in prior art
In≤8ppm, and B, D type impurity is required to add the report of tight 0.5 grade of bearing steel smelting production technology than GB, it is however generally that,
Requirement can only partly be met.
Content of the invention
For overcoming above technological difficulties, the present invention provides one kind can be while by the control of Ti content in≤15ppm, O containing control
System is in≤8ppm, and B, D type impurity is required to add tight 0.5 grade of bearing steel smelting refine slag making formula and smelting than GB
Refining technology,.
The technical solution adopted in the present invention is：A kind of refining bearing steel slag formula constitutes：SiO2：≤ 6, Al2O3：
40～50, CaO：45～55, MgO：≤ 8, TiO2≤0.05, Fe2O3≤2, granularity：3-45mm, basicity controls 10 or so.
A kind of bearing steel smelting process using above-mentioned refining slag, step is as follows：
The first step：Converter tapping, using 20Kg carbon dust pre-deoxidation, time control of tapping is in 5 ~ 6min, and alloy is added using shaking by force,
Tap about 80 seconds after starting（Tap about 35t）When start alloying, addition sequence is：Ferro-aluminum-carbon dust-alloy-Calx, alloy
Chute will be directed at steel stream；Ferro-aluminum adds carbon dust after adding, and adds carbon dust and starts buggy ladle, impacts carbon dust with steel stream, after melting
Adduction is golden again.Alloy and Calx will also be added separately to, and add after a kind of impact of material steel stream is melted and add another kind of material again, forbid collection
Middle addition；
Second step：Behind refining furnace seat, above-mentioned refining slag 600Kg is disposably added；Deoxidizer is added must be after slag charge be added
Add, LF refining furnace superintendent will rationally control the addition of deoxidizer according to the situation of arriving at a station, a small amount of addition original of many batches of strict implement
Then, initial smelting period is diffused deoxidation using mixing part carbon dust based on 70 carborundums, the control of 70 carborundum consumptions 80kg with
Above, suitably can be added according to slag deoxidation effect；With 70 carborundums, smelting process slag is safeguarded, 70 carborundum consumption controls
System has made white slag in 80kg or so before accomplishing to smelt sample 1, while avoiding deoxidizer in slag, insufficiently burnt situation occurs in a large number.
Middle and late stage slag is safeguarded and wants a small amount of addition principle of many batches of strict implement.
3rd step：LF stove outbound composition enters in strict accordance with smelting process card LF refining furnace outbound Composition Control target call
Row control.Avoid RH refining furnace adjusting component as far as possible, particularly avoid and increase Al in RH stove.
The invention has the beneficial effects as follows：As Al2O3 content is improved in the refining slag constituent, slag is reduced
Viscosity and fusing point, improve the burn-off rate of slag, make refinery cinder rapid slagging, effectively improve submerged arc effect, reduce steel
Middle abnormal nitrogen pick-up and oxygen uptake, strengthen slag desulfurization and deoxidizing capacity, and slag melting lazy flow is good, to steel inclusion energy of adsorption
Power is strong, while reducing slag TiO2 content, reduces Ti content in steel, and the present invention solves Bearing Steel during Production O simultaneously and contains
The control problem of amount, B, D class and TiN field trash, the quality to improving bearing steel plays key effect.
Specific embodiment
With reference to embodiment, the present invention is further described.
A kind of bearing steel is in refining process slag making materials formula：SiO2：≤ 6, Al2O3：40～50, CaO：45～55,
MgO：≤ 8, TiO2≤0.05, Fe2O3≤2, granularity：3-45mm, basicity controls 10 or so.
Using the bearing steel smelting process of above-mentioned refining slag, its concrete technology step is：
The first step：Converter tapping, using 20Kg carbon dust pre-deoxidation, time control of tapping is in 5 ~ 6min, and alloy is added using shaking by force,
Tap about 80 seconds after starting（Tap about 35t）When start alloying, addition sequence is：Ferro-aluminum -- carbon dust -- alloy Calx,
Alloy chute will be directed at steel stream；Ferro-aluminum adds carbon dust after adding, and adds carbon dust and starts buggy ladle, impacts carbon dust with steel stream, changes
After opening, adduction is golden again.Alloy and Calx will also be added separately to, and add after a kind of impact of material steel stream is melted and add another kind of material again, prohibit
Only concentrate and add；
Second step：Behind refining furnace seat, the special refining slag 600Kg of bearing steel is disposably added；Deoxidizer is added must be in slag charge
Add after adding, LF refining furnace will rationally control the addition of deoxidizer according to the situation of arriving at a station, many batches of strict implement is a small amount of to be added
Enter principle, initial smelting period is diffused deoxidation using part carbon dust is mixed based on 70 carborundums, and the control of 70 carborundum consumptions exists
More than 80kg, suitably can be added according to slag deoxidation effect；With 70 carborundums, smelting process slag is safeguarded, 70 carborundums
Consumption controls in 80kg or so, has made white slag before accomplishing to smelt sample 1, while avoiding in slag deoxidizer insufficiently burnt situation in a large number
Occur.Middle and late stage slag is safeguarded and wants a small amount of addition principle of many batches of strict implement.
3rd step：LF stove outbound composition enters in strict accordance with smelting process card LF refining furnace outbound Composition Control target call
Row control.Avoid RH refining furnace adjusting component as far as possible, particularly avoid and increase Al in RH.
Embodiment 1：Bearing steel using the refine slag melting of the present invention（8 stoves）With Zheng Shaobo etc. in May, 2005 China
In 2005 collection of thesis of special steel annual meeting《The control of Ti content in high-carbon-chromium bearing steel》Chromium is added using silicomanganese pre-deoxidation, hyperoxia position
Ferrum and low alkalinity refining slag are contrasted, and are shown in Table 1, and in two kinds of slag system control steel, Ti contents level is suitable, the essence for being provided using invention
The oxygen content of refining slag melting bearing steel is lower, fully meets high standard bearing steel requirement.
Table 1 low alkalinity refining slag and the present invention provide the bearing steel index contrast of refine slag melting（%）
Embodiment 2：
Original uses synthetic slag Smelting Bearing Steel（10 stove steel）Bearing steel with the refine slag melting for being provided using the present invention（10 stoves
Steel）Relative analyses, by TiO2 content, strand total oxygen content, field trash pair in Ti content in sulfur content in steel, steel, refining slag
Than being shown in Table 2 and table 3, it is seen that the bearing steel quality of the refine slag melting for being provided using the present invention is substantially better than original and uses synthetic slag
The bearing steel of smelting.
Table 2 is former to provide the contrast of refining slag Smelting Bearing Steel index using synthetic slag and invention（%）
| Index | S content in steel | Ti content in steel | Refining slag TiO2Content | Total oxygen content | Oxygen content≤8ppm ratio |
| Original uses synthetic slag | 0.0023 | 0.0028 | 0.47 | 0.0009 | 56% |
| Invention provides refining slag | 0.0010 | 0.0013 | 0.22 | 0.0006 | 100% |
Table 3 is former to provide the contrast of refining slag Smelting Bearing Steel field trash using synthetic slag and invention
As can be seen here, by using the bearing steel of the refine slag melting of the present invention, its O content≤8ppm ratio is risen to by 56%
100%, B are thick, the thick field trash of D is basically eliminated, and in steel, Ti is reduced to 13ppm by 28ppm, fully meet wanting for high standard bearing steel
Ask.
Claims (2)
1. a kind of Smelting Bearing Steel refining slag composition is：SiO2：≤ 6, Al2O3：40～50, CaO：45～55, MgO：≤ 8,
TiO2≤0.05, Fe2O3≤2, granularity：3-45mm, basicity controls 10 or so.
2. a kind of using Smelting Bearing Steel as claimed in claim 1 refining slag smelting process, step is as follows：
The first step：Converter tapping, using 20Kg carbon dust pre-deoxidation, time control of tapping is in 5 ~ 6min, and alloy is added using shaking by force,
Tap about 80 seconds after starting（Tap about 35t）When start alloying, addition sequence is：Ferro-aluminum-carbon dust-alloy-Calx, alloy
Chute will be directed at steel stream；Ferro-aluminum adds carbon dust after adding, and adds carbon dust and starts buggy ladle, impacts carbon dust with steel stream, after melting
Adduction is golden again；Alloy and Calx will also be added separately to, and add after a kind of impact of material steel stream is melted and add another kind of material again, forbid collection
Middle addition；
Second step：Behind refining furnace seat, above-mentioned refining slag 600Kg is disposably added；Deoxidizer is added must be after slag charge be added
Add, LF refining furnace will rationally control the addition of deoxidizer according to the situation of arriving at a station, a small amount of addition principle of many batches of strict implement,
Initial smelting period is diffused deoxidation using mixing part carbon dust based on 70 carborundums, the control of 70 carborundum consumptions more than 80kg,
Suitably can be added according to slag deoxidation effect；With 70 carborundums, smelting process slag is safeguarded, 70 carborundum consumptions control
In 80kg or so, before accomplishing to smelt sample 1, white slag is made, insufficiently burnt situation occurs in a large number while avoiding deoxidizer in slag；In
Later stage slag is safeguarded and wants a small amount of addition principle of many batches of strict implement；
3rd step：LF stove outbound composition is controlled in strict accordance with smelting process card LF refining furnace outbound Composition Control target call
System；Avoid RH refining furnace adjusting component as far as possible, particularly avoid and increase Al in RH stove.
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109777918A (en) * | 2019-02-20 | 2019-05-21 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method refining high-carbon-chromium bearing steel inclusion particle |
| CN111057948A (en) * | 2019-12-14 | 2020-04-24 | 石家庄钢铁有限责任公司 | Narrow-range production control method for rare earth elements La and Ce in rare earth bearing steel |
| CN111893245A (en) * | 2020-07-08 | 2020-11-06 | 武汉钢铁有限公司 | Ultra-low carbon steel refining slag modifier and modification method thereof |
| CN112094981A (en) * | 2020-11-12 | 2020-12-18 | 北京科技大学 | Method for removing bubbles in No. 45 steel |
| CN113073269A (en) * | 2021-03-31 | 2021-07-06 | 安徽富凯特材有限公司 | Smelting process of high-carbon chromium stainless bearing steel parent metal |
| CN113234892A (en) * | 2021-04-29 | 2021-08-10 | 南京钢铁股份有限公司 | Method for improving desulfurization rate of bearing steel in LF (ladle furnace) refining process |
| CN113699314A (en) * | 2021-09-09 | 2021-11-26 | 江苏利淮钢铁有限公司 | Control method for tapping slag condition of high-carbon and high-alloy steel 90t converter |
| CN113930586A (en) * | 2021-09-23 | 2022-01-14 | 南京钢铁股份有限公司 | Method for producing white slag in bearing steel LF refining process |
| CN114635016A (en) * | 2022-02-17 | 2022-06-17 | 包头钢铁（集团）有限责任公司 | Refining slag system suitable for producing bearing steel by 120-ton refining furnace |
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Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109777918A (en) * | 2019-02-20 | 2019-05-21 | 江阴兴澄特种钢铁有限公司 | A kind of external refining production method refining high-carbon-chromium bearing steel inclusion particle |
| CN111057948A (en) * | 2019-12-14 | 2020-04-24 | 石家庄钢铁有限责任公司 | Narrow-range production control method for rare earth elements La and Ce in rare earth bearing steel |
| CN111893245A (en) * | 2020-07-08 | 2020-11-06 | 武汉钢铁有限公司 | Ultra-low carbon steel refining slag modifier and modification method thereof |
| CN112094981A (en) * | 2020-11-12 | 2020-12-18 | 北京科技大学 | Method for removing bubbles in No. 45 steel |
| CN113073269A (en) * | 2021-03-31 | 2021-07-06 | 安徽富凯特材有限公司 | Smelting process of high-carbon chromium stainless bearing steel parent metal |
| CN113234892A (en) * | 2021-04-29 | 2021-08-10 | 南京钢铁股份有限公司 | Method for improving desulfurization rate of bearing steel in LF (ladle furnace) refining process |
| CN113699314A (en) * | 2021-09-09 | 2021-11-26 | 江苏利淮钢铁有限公司 | Control method for tapping slag condition of high-carbon and high-alloy steel 90t converter |
| CN113930586A (en) * | 2021-09-23 | 2022-01-14 | 南京钢铁股份有限公司 | Method for producing white slag in bearing steel LF refining process |
| CN114635016A (en) * | 2022-02-17 | 2022-06-17 | 包头钢铁（集团）有限责任公司 | Refining slag system suitable for producing bearing steel by 120-ton refining furnace |
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