CN105382229B - A kind of method for improving coiled sheet surface quality - Google Patents
A kind of method for improving coiled sheet surface quality Download PDFInfo
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- CN105382229B CN105382229B CN201510698039.XA CN201510698039A CN105382229B CN 105382229 B CN105382229 B CN 105382229B CN 201510698039 A CN201510698039 A CN 201510698039A CN 105382229 B CN105382229 B CN 105382229B
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- continuous casting
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- steel billet
- casting steel
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/12—Accessories for subsequent treating or working cast stock in situ
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/0081—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for slabs; for billets
Abstract
The invention belongs to steelmaking technical field, a kind of method for improving coiled sheet surface quality is disclosed, including：By continuous casting steel billet cooling down；Continuous casting steel billet after cooling is progressively heated, until centre of surface temperature reaches 450 DEG C~550 DEG C；Continuous casting steel billet after the heating is placed in natural cooling in air；Vibrations are carried out to the continuous casting steel billet after air cooling and turn over base operation, promote surface protection slag to come off；Wherein, the concrete operations that the continuous casting steel billet is progressively heated are realized by the heat transfer between high-temperature medium and low temperature continuous casting slab, the surface temperature of slow lifting continuous casting steel billet；600 DEG C~900 DEG C of the temperature of the high-temperature medium；The temperature range that the continuous casting steel billet temperature initially cooled down exists with the high-temperature medium is 400 DEG C~500 DEG C.The method that surface quality is lifted is realized the invention provides a kind of process that covering slag is made steel by removing slab surface.
Description
Technical field
The present invention relates to steelmaking technical field, more particularly to a kind of method for improving coiled sheet surface quality.
Background technology
During sheet billet continuous casting, after slab washes away through cooling water, surface can still adhere to the covering slag of remaining.The continuous casting later stage,
For ultra-low-carbon steel slab of the mass fraction 0.0010%~0.0100% of carbon, its hardness is relatively low, and steel slab surface remnants are protected
Shield slag is easily pressed directly into by roller, is attached to surface, it is difficult to come off.
Before slab rolling, furnace temp general control is at 1150 DEG C~1250 DEG C, and steel slab surface remaining covering slag
Fusing point is at 900 DEG C~1100 DEG C.During heating, remaining covering slag fusing, and the iron scale that now steel slab surface is produced extremely is dredged
Pine, the covering slag of molten condition penetrates iron scale and is attached directly to steel matrix surface, is difficult with oxidation in steel rolling de-scaling
Iron sheet comes off together, ultimately results in the surface of steel plate that remaining covering slag is stayed in after rolling, influences the surface quality of steel plate.Production is real
Middle discovery is trampled, if the covering slag area of steel slab surface residual is more than 1mm2, fail to remove during subsequently rolling dephosphorization, most
Eventually finished steel plate surface can be caused black line defect occur.
The content of the invention
The present invention provides a kind of method for improving coiled sheet surface quality, solves soft surface of steel plate in the prior art and protects
Slag press-in steel plate influences the technical problem of its surface quality；The technique effect of lifting surface of low-carbon steel quality is reached.
In order to solve the above technical problems, the invention provides a kind of method for improving coiled sheet surface quality, including：
By continuous casting steel billet cooling down；
Continuous casting steel billet after cooling is progressively heated, until centre of surface temperature reaches 450 DEG C~550 DEG C；
Continuous casting steel billet after will heat up is placed in natural cooling in air；
Vibrations are carried out to the continuous casting steel billet after air cooling and turn over base operation, promote surface protection slag to come off；
Wherein, the concrete operations that the continuous casting steel billet is progressively heated are by the heat between high-temperature medium and low temperature continuous casting slab
Conduction is realized, slowly lifts the surface temperature of continuous casting steel billet；
600 DEG C~900 DEG C of the temperature of the high-temperature medium；The continuous casting steel billet temperature initially cooled down is deposited with the high-temperature medium
Temperature range be 400 DEG C~500 DEG C.
Further, the area that the covering slag remnants points of the slab surface of base operation are turned over through vibrations is less than 5mm2, and
It is more than 1mm in the range of every square metre2Covering slag remnants point number be less than 3.
Further, the high-temperature medium uses high temperature plate；
The continuous casting steel billet is clipped between two blocks of high temperature plates.
Further, the high temperature plate is more than or equal to 0.1% high carbon steel sheet using carbon mass fraction.
Further, the centre of surface temperature range of the high carbon steel sheet is 600 DEG C~900 DEG C, is completely covered on described
The upper and lower surface of continuous casting steel billet, until centre of surface temperature reaches 450 DEG C~550 DEG C.
Further, the initial temperature of the continuous casting steel billet after cooling is maintained at less than 100 DEG C.
The one or more technical schemes provided in the embodiment of the present application, have at least the following technical effects or advantages：
1st, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, by low temperature continuous casting slab to high temperature shape
Oxidation during state is progressively slowly varying, successively forms a large amount of iron scales so that the protection of surface attachment in steel slab surface
Slag defective material can depart from slab main body, be removed so as to turn over base operation by vibrations with iron scale, it is to avoid press-in steel plate, it is ensured that
Surface quality；Simultaneously because using low-temperature heat, it is to avoid covering slag is melted, it is ensured that removal efficiency.
2nd, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, continuous casting steel billet is grasped through cooling before heating
Make, reduce board briquette, meet high-temperature medium and form larger temperature difference space so that the slab cold shrinkage and thermal expansion time in temperature-rise period
With amplitude enhancing, it is easy to form loose iron scale and follow-up strip operation.
3rd, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, continuous casting plate is covered in using high temperature plate
The both sides of base carry out heat transfer, on the one hand realize and uniformly transfer, on the other hand, using high carbon steel sheet, are protected using its high rigidity
Slag is difficult to the characteristic adhered to so that its contact heat transfer process smoothly without produce adhesion the problems such as, reduce further protection
The risk of the surface quality of slag influence continuous casting billet.
4th, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, the high-temperature medium used is continuous casting
The high-carbon steel plate in latter stage.When the present invention uses such plate, it is not necessary to separately heated up, but directly chosen in continuous casting link
Go out the plate that temperature range after crystallizer is down to 600 DEG C~900 DEG C Sizes.Energy-conserving and environment-protective, effectively utilize continuous casting high temperature plate
The physical thermal of part.
Embodiment
The embodiment of the present application solves soft steel in the prior art by providing a kind of method for improving coiled sheet surface quality
Plate surface covering slag press-in steel plate influences the technical problem of its surface quality；The technology effect of lifting surface of low-carbon steel quality is reached
Really.
In order to solve the above technical problems, the general thought that the embodiment of the present application provides technical scheme is as follows：
A kind of method for improving coiled sheet surface quality, including：
By continuous casting steel billet cooling down；
Continuous casting steel billet after cooling is progressively heated, until centre of surface temperature reaches 450 DEG C~550 DEG C；
Continuous casting steel billet after will heat up is placed in natural cooling in air；
Vibrations are carried out to the continuous casting steel billet after air cooling and turn over base operation, promote surface protection slag to come off；
Wherein, the concrete operations that the continuous casting steel billet is progressively heated are by the heat between high-temperature medium and low temperature continuous casting slab
Conduction is realized, slowly lifts the surface temperature of continuous casting steel billet；
600 DEG C~900 DEG C of the temperature of the high-temperature medium；The continuous casting steel billet temperature initially cooled down is deposited with the high-temperature medium
Temperature range be 400 DEG C~500 DEG C.
By the above as can be seen that by slowly heat up and continuous casting billet effect of expanding with heat and contract with cold on continuous casting billet surface
Form loose iron scale so that covering slag is attached to disengaging slab main body on iron scale, base operation is turned over by vibrations
Remove, it is to avoid it influences the surface quality of the low carbon steel plate of soft；In addition, enabling covering slag to be in all the time by temperature control
Solid-state can also meet slab heating needs simultaneously, it is to avoid melting too covering slag influence removal effect.
In order to be better understood from above-mentioned technical proposal, below in conjunction with Figure of description and specific embodiment to upper
State technical scheme to be described in detail, it should be understood that the specific features in the embodiment of the present invention and embodiment are to the application skill
The detailed description of art scheme, rather than the restriction to technical scheme, in the case where not conflicting, the embodiment of the present application
And the technical characteristic in embodiment can be mutually combined.
A kind of method for improving coiled sheet surface quality provided in an embodiment of the present invention, including：
By continuous casting steel billet cooling down；
Continuous casting steel billet after cooling is progressively heated, until centre of surface temperature reaches 450 DEG C~550 DEG C；
Continuous casting steel billet after will heat up is placed in natural cooling in air；
Vibrations are carried out to the continuous casting steel billet after air cooling and turn over base operation, promote surface protection slag to come off；
Wherein, the concrete operations that the continuous casting steel billet is progressively heated are by the heat between high-temperature medium and low temperature continuous casting slab
Conduction is realized, slowly lifts the surface temperature of continuous casting steel billet；
600 DEG C~900 DEG C of the temperature of the high-temperature medium；The continuous casting steel billet temperature initially cooled down is deposited with the high-temperature medium
Temperature range be 400 DEG C~500 DEG C.
The area that the covering slag remnants points of the slab surface of base operation are turned over through vibrations is less than 5mm2, and every square metre of model
It is more than 1mm in enclosing2Covering slag remnants point number be less than 3.
The high-temperature medium uses high temperature plate；The continuous casting steel billet is clipped between two blocks of high temperature plates.
The high temperature plate is more than or equal to 0.1% high carbon steel sheet using carbon mass fraction.
The centre of surface temperature range of the high carbon steel sheet is 600 DEG C~900 DEG C, is completely covered on the continuous casting steel billet
Upper and lower surface, until centre of surface temperature reaches 450 DEG C~550 DEG C.
The initial temperature of the continuous casting steel billet after cooling is maintained at less than 100 DEG C.
It will specifically introduce the above method below.
Surface temperature is cooled to after ultra-low-carbon steel slab continuous casting less than 100 DEG C；
Select the high-carbon steel slab for mass fraction >=0.1% for taking carbon else, its length surpasses with width not less than pending
Mild steel slab, it is ensured that its centre of surface temperature is up to 600 DEG C -900 DEG C.This kind of high-carbon steel slab directly terminates from continuous casting in production
Chosen in the slab not cooled down completely also afterwards, because the corner radiating of slab is very fast, cause the temperature at slab Kuan Mian centers slightly higher
In corner temperature, as long as wide face central temperature reaches that 600-900 DEG C of slab is applicable in the present invention；
Ultra-low-carbon steel slab neatly intersects with high-carbon steel slab to be stacked, and heat transfer time is kept for 4-5 hours；When stacking it is ensured that
There is high-carbon steel slab in two wide faces of each ultra-low-carbon steel slab, stack neatly, the wide face of ultra-low-carbon steel slab must not be sudden and violent
Dew in atmosphere, to ensure that heat transfer is abundant, controls the generation of iron scale.After heat transfer terminates, ultra-low-carbon steel slab centre of surface
Temperature is between 450 DEG C~550 DEG C.
After heat transfer terminates, slab is separated and piled up；Wherein ultra-low-carbon steel slab is positioned over that hemisphere is cold, and upper surface is no longer
Contacted with other slabs.
Ultra-low-carbon steel slab is cooled to after less than 100 DEG C in atmosphere, and 1-3 times is carried out to it and turns over base operation, now, surface
Remaining covering slag comes off, and is more than 5mm it is ensured that turning over steel slab surface after base and area being not present in production2The remaining point of covering slag,
And every square metre of inner area is more than 1mm2Covering slag remnants point be not more than 3.
Temperature is reduced to less than 100 DEG C after ultra-low-carbon steel slab continuous casting, then stacks biography by the high-carbon steel slab with high temperature
Heat, is heated to 500 DEG C or so.Stack ultra-low-carbon steel slab surface in heat transfer temperature-rise period and produce a large amount of iron scales, and it is remaining
Covering slag can't be melted, as iron scale is peeled off together during what remaining covering slag can be below turn over base.
In addition, Ultra-low carbon steel slab surface temperature change, can cause slab to expand with heat and contract with cold, the original iron scale of steel slab surface
Easily peel off.
For the high-carbon steel grade of mass fraction >=0.1% of carbon, because hardness is larger, the remaining covering slag of casting process is difficult
To be attached to steel slab surface, so stacking heating therewith from the steel grade of carbon content >=0.1%.
Turn over iron scale and remaining covering slag that base operation mainly uses vibrations and Action of Gravity Field to remove surface.
After Ultra-low carbon sheet billet continuous casting, by " base concussion is turned in slab cooling-different temperatures slab, which is stacked, to conduct heat-" in invention
Operation, the remaining covering slag removal effect on surface is good, has prevented the generation of surface of steel plate covering slag insertion.
Following example is used to illustrate the present invention, but protection scope of the present invention is not limited in following examples.
The mass fraction of 3 blocks of pending ultra-low-carbon steel slab carbon is respectively 0.0052%, 0.013%, 0.0088%, is surveyed
The temperature for obtaining its Kuan Mian center of continuous casting later stage is respectively 67 DEG C, 82 DEG C, 49 DEG C, and base shape size (length x width x thickness) is
9800×1500×230mm；
The mass fraction for the 4 blocks of high-carbon steel slab carbon chosen is respectively 0.23%, 0.38%, 0.14%, 0.25%, is measured
The temperature at its Kuan Mian center of continuous casting later stage is respectively 695 DEG C, 844 DEG C, 748 DEG C, 627 DEG C, and (length x width x is thick for base shape size
Degree) it is 10000 × 1600 × 230mm；
7 blocks of slabs are intersected and stacked neatly, are topmost high-carbon steel slab with nethermost slab, are placed 4.5 hours,
It is respectively 462 DEG C, 525 DEG C, 533 DEG C to measure the wide face central temperature of 3 blocks of ultra-low-carbon steel slabs；
3 blocks of ultra-low-carbon steel slabs be respectively placed on ground cool down, wide face central temperature be reduced to respectively 52 DEG C, 62 DEG C,
68℃；
3 blocks of ultra-low-carbon steel slabs are turned over base 1 time, 2 times, 1 time respectively.Turn over after base and to blow off casting billet surface with hair-dryer, to casting
Base surface is checked that it is 3mm to find maximum remaining covering slag area2.The upper area of every square metre of casting billet surface is more than 1mm2's
Remaining covering slag quantity is respectively 0.34,1.23,2.02.
The one or more technical schemes provided in the embodiment of the present application, have at least the following technical effects or advantages：
1st, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, by low temperature continuous casting slab to high temperature shape
Oxidation during state is progressively slowly varying, successively forms a large amount of iron scales so that the protection of surface attachment in steel slab surface
Slag defective material can depart from slab main body, be removed so as to turn over base operation by vibrations with iron scale, it is to avoid press-in steel plate, it is ensured that
Surface quality；Simultaneously because using low-temperature heat, it is to avoid covering slag is melted, it is ensured that removal efficiency.
2nd, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, continuous casting steel billet is grasped through cooling before heating
Make, reduce board briquette, meet high-temperature medium and form larger temperature difference space so that the slab cold shrinkage and thermal expansion time in temperature-rise period
With amplitude enhancing, it is easy to form loose iron scale and follow-up strip operation.
3rd, the method for the raising coiled sheet surface quality provided in the embodiment of the present application, continuous casting plate is covered in using high temperature plate
The both sides of base carry out heat transfer, on the one hand realize and uniformly transfer, on the other hand, using high carbon steel sheet, are protected using its high rigidity
Slag is difficult to the characteristic adhered to so that its contact heat transfer process smoothly without produce adhesion the problems such as, reduce further protection
The risk of the surface quality of slag influence continuous casting billet.
It should be noted last that, above embodiment is merely illustrative of the technical solution of the present invention and unrestricted,
Although the present invention is described in detail with reference to example, it will be understood by those within the art that, can be to the present invention
Technical scheme modify or equivalent substitution, without departing from the spirit and scope of technical solution of the present invention, it all should cover
Among scope of the presently claimed invention.
Claims (6)
1. a kind of method for improving coiled sheet surface quality, it is characterised in that including：
By continuous casting steel billet cooling down；
Continuous casting steel billet after cooling is progressively heated, until centre of surface temperature reaches 450 DEG C~550 DEG C；
Continuous casting steel billet after will heat up is placed in natural cooling in air；
Vibrations are carried out to the continuous casting steel billet after air cooling and turn over base operation, promote surface protection slag to come off；
Wherein, the concrete operations that the continuous casting steel billet is progressively heated are by the heat transfer between high-temperature medium and low temperature continuous casting slab
Realize, the surface temperature of slow lifting continuous casting steel billet；
600 DEG C~900 DEG C of the temperature of the high-temperature medium；The continuous casting steel billet temperature initially cooled down exists with the high-temperature medium
Temperature range is 400 DEG C~500 DEG C.
2. the method for coiled sheet surface quality is improved as claimed in claim 1, it is characterised in that：The continuous casting of base operation is turned over through vibrations
The area of the covering slag remnants points of steel slab surface is less than 5mm2, and more than 1mm in the range of every square metre2Covering slag remnants point
Number is less than 3.
3. the method for coiled sheet surface quality is improved as claimed in claim 1, it is characterised in that：The high-temperature medium uses high temperature
Plate；
The continuous casting steel billet is clipped between two blocks of high temperature plates.
4. the method for coiled sheet surface quality is improved as claimed in claim 3, it is characterised in that：The high temperature plate uses carbonaceous
Measure the high carbon steel sheet that fraction is more than or equal to 0.1%.
5. the method for coiled sheet surface quality is improved as claimed in claim 4, it is characterised in that：In the surface of the high carbon steel sheet
Heart temperature range is 600 DEG C~900 DEG C, the upper and lower surface of the continuous casting steel billet is completely covered on, until the continuous casting steel billet
Centre of surface temperature reaches 450 DEG C~550 DEG C.
6. the method for coiled sheet surface quality is improved as claimed in claim 1, it is characterised in that：The continuous casting steel billet is after cooling
Initial temperature be maintained at less than 100 DEG C.
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| CN201510698039.XA CN105382229B (en) | 2015-10-23 | 2015-10-23 | A kind of method for improving coiled sheet surface quality |
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| CN201510698039.XA CN105382229B (en) | 2015-10-23 | 2015-10-23 | A kind of method for improving coiled sheet surface quality |
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| CN105382229B true CN105382229B (en) | 2017-08-25 |
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| JPS63295060A (en) * | 1987-05-27 | 1988-12-01 | Kawasaki Steel Corp | Method for discriminating adhesion of fusion cutting slag of ingot |
| CN100457326C (en) * | 2007-04-20 | 2009-02-04 | 攀枝花钢铁(集团)公司 | Method for controlling the cross crack of blank angle of high nitrogen steel casting board containing vanadium |
| CN102441648A (en) * | 2010-10-08 | 2012-05-09 | 攀钢集团钢铁钒钛股份有限公司 | Method for continuously casting steel plate billets for automotive frames |
| CN104084550B (en) * | 2014-07-28 | 2016-04-27 | 重庆钢铁(集团)有限责任公司 | The continuous casting steel billet production control method of rolling slab |
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Address after: 100041 Shijingshan Road, Beijing, No. 68, No. Patentee after: Shougang Group Co. Ltd. Address before: 100041 Shijingshan Road, Beijing, No. 68, No. Patentee before: Capital Iron & Steel General Company |
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