CN104785737A - Method for eliminating defect of metal particles on surface of continuous casting - Google Patents
Method for eliminating defect of metal particles on surface of continuous casting Download PDFInfo
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- CN104785737A CN104785737A CN201510163794.8A CN201510163794A CN104785737A CN 104785737 A CN104785737 A CN 104785737A CN 201510163794 A CN201510163794 A CN 201510163794A CN 104785737 A CN104785737 A CN 104785737A
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- continuous casting
- mouth
- river
- mesopore
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Abstract
The invention discloses a method for eliminating the defect of metal particles on the surface of a continuous casting. By means of the method that the head shape of a stopper and the appearance dimension of a water gap are improved and the adding mode of a covering agent is adjusted, the defect can be eliminated in the mode of reducing the cooling intensity of a crystallizer. By means of the method, the rate of finished products is increased, and meanwhile due to the reduction of the coping amount, the loss of a grinding wheel, the coping time loss and the manual cost are greatly reduced correspondingly.
Description
Technical field
The present invention relates to a kind of method eliminating continuous casting billet surface metal grain defect.
Background technology
Continuous casting billet surface metal grain defect multidigit outer arc middle part in continuous casting billet, show as cluster-shaped or individual particle shape, particle mostly is circle, and diameter≤1.5mm, particle is connected with matrix.Containing metal particle defect continuous casting billet in hot continuous rolling heating de-scaling process more difficult removal, do not remove the particle operation of rolling rolled formed pointed at both ends, length according to the different willow leaf shape defect of cold plate thickness, defective effect yield rate.This defect at home and abroad there is no report, and its genetic analysis is solved to this defect and need do from element task.This problem is existing more than 4 years so far from impact in 2011, by this defective effect, continuous casting billet without the monthly reduction by 24.5% of reconditioning rate, monthly 110.25 tons of reconditioning loss amount.Therefore be necessary that research is known continuous casting billet surface metal grain defect producing cause and provides a kind of eliminable method.
Summary of the invention
The present invention aims to provide a kind of method eliminating continuous casting billet surface metal grain defect, improves yield rate.
The invention provides a kind of method eliminating continuous casting billet surface metal grain defect, it is characterized in that:
(1) double-deck coverture is adopted
To containing metal particle heat and not containing metal particle heat crystallizer protecting residue melt cinder sample sample analysis, result shows, Al in containing metal particle heat melt cinder
2o
3, Cr
2o
3content is respectively 8.29%, 1.42%, compare not containing metal particle defect heat respectively high by 0.223%, 0.207%, especially Al
2o
3, it is high by 2.0% that containing metal particle heat melt cinder compares former slag, and casting process exists secondary oxidation of steel.A large amount of Al that secondary oxidation of steel produces
2o
3enter slag and easily generate calcium aluminium Huangshi (2CaO.Al
2o
3.SiO
2) and nepheline (Na
2o.Al
2o
3.2SiO
2), cause slag density to be deteriorated, provide precondition for metallic particles produces.
For this adjusts tundish covering flux basicity and feed postition, to improve its dross inclusion adsorption ability and to prevent Metal in Tundish to be oxidized.Before and after design, coverture composition sees the following form:
Coverture Adding Way is added by former individual layer and is adjusted to double-deck, optimizing afterwards except alkaline covering agent, covering the magnesia high-melting-point coverture of a floor height still thereon except adding upper table.Through optimizing, to after refining, continuous casting production, crystallizer and strand sample respectively, utilize nitrogen oxygen analyzer to analyze T. [O] changes of contents, result shows that refining terminates obviously to reduce to tundish process secondary oxidation degree, and crystallizer, strand T. [O] content are lower than 30ppm.
(2) primary cooling water optimization
Adopt the method reducing crystallizer primary cooling water intensity, contribute to improving mold liquid level molten steel temperature, improve the change slag speed of covering slag, Absorbable organic halogens melt cinder thickness, even initial solidification shell cooling, forms the uniform base shell of thickness.Crystallizer wide cooling water inflow is reduced to 4000L/min by former 4300L/min, and it is constant that crystallizer leptoprosopy cooling water inflow maintains 410L/min.
(3) the new mouth of a river is set
Adopt hydraulics experiment, exploitation updip 10 °, mouth of a river side opening area and mesopore area ratio be 1.94, the trapezoidal mouth of a river of V-arrangement kerve, steel stream upper reaches stock stable and uniform in crystallizer can be realized and circulate, both can improve mold liquid level temperature, and liquid level slag can be prevented again.
(4) new stopper is set
Because containing metal particle defect heat steel pouring process mold liquid level seethes seriously, start suspection relevant with liquid fluctuating, find being poured stopper system inspection afterwards, the perforate of onsite application stopper head, be poured rear perforate position and be full of steel column, steel column for cast terminate continuous casting production blind plate stop cast after molten steel recharge to caused by stopper inside.According to Fluent ejector negative pressure mechanism of production result of study, continuous-casting steel pouring process continuous casting tundish stopper head is similar to ejector, stopper head position of widening the view is similar to the spout that driving fluid formed with working fluid mixing position, molten steel is working fluid, and perforate stopper internal gas is driving fluid.Fluent ejector negative pressure mechanism of production is pointed out, internal negative pressure and effluxvelocity, pipe diameter are relevant, effluxvelocity is larger, pipe diameter is less, negative pressure value is larger, steel pouring process poring rate increases, stopper head produces negative pressure and increases, and it is obvious all the more that stopper endoporus gas is sucked crystallizer phenomenon by force.
Air is inhaled in crystallizer except causing secondary oxidation of steel to generate except category-B field trash, bubble floating passes through slag interface, when bubble volume reaches certain value and bubble natural buoyancy is greater than the interfacial surface tension of bubble-molten steel, molten steel can enter liquid slag layer with bubble floating, the molten steel that major part is brought into can because returning crystallizer molten steel with bubble disengagement again, a small amount of molten steel is only had to be formed rapidly spherical to reduce its surface free energy by the effect of its own face tension force, glomeration drop not yet has enough time to return molten steel just because upper reaches stock effect backrush is to close position, the mouth of a river, melt cinder with steel ball enters meniscus in both sides, the mouth of a river, part enters slag bar, part enters initial solidification shell by melt cinder channel pressure squeezing action and forms surface metal particle.
Therefore for preventing steel pouring process stopper head air-breathing, spy improves stopper head, is adjusted to solid design by former hollow design, stops bubble in crystallizer and produces.
Innovative point of the present invention is mainly reflected in:
A. double-deck coverture is adopted, to improve its dross inclusion adsorption ability and to prevent Metal in Tundish to be oxidized.
B. primary cooling water optimization, adopts and reduces crystallizer intensity of cooling method, contributes to improving mold liquid level molten steel temperature, improves protection scorification slag speed.
C. develop the new mouth of a river, updip 10 °, mouth of a river side opening area and mesopore area ratio are 1.94.Stock stable and uniform circulation in steel stream upper reaches in crystallizer can be realized, both can improve mold liquid level temperature, and liquid level slag can be prevented again.
D. develop new stopper, use atresia stopper.For preventing steel pouring process stopper head air-breathing, spy improves stopper head, is adjusted to solid design by former hollow design, stops bubble in crystallizer and produces.
The method of elimination continuous casting billet surface metal grain defect provided by the invention, improves yield rate; Simultaneously because reconditioning quality reduces, corresponding emery wheel loss, reconditioning time loss and cost of labor all have and reduce by a relatively large margin.
Accompanying drawing explanation
Fig. 1 is sampling point and total oxygen content graph of a relation in embodiment 1.
Fig. 2 is the structural representation of mouth of a river side opening.
Fig. 3 is the structural representation of stopper.
In figure, 1 is barred body, and 2 is caput, and 3 is mesopore, and 4 is front mesopore.
Detailed description of the invention
Further illustrate the present invention below by embodiment, but be not limited to following examples.
Embodiment 1:
Be stainless steel for 304, cast specification 200mm × 1235mm, casting process is as follows:
4.1 connect and water the first stove and unwrap greatly and water to middle bag weight 18 tons, add low melting point high alkalinity coverture 180kg, after steel speed to be poured reaches 0.80m/min, add high-melting-point height Mg matter coverture 50kg, casting process adds high-melting-point height Mg matter coverture 30-50kg by every stove and adds.Casting process gets LF departures front steel sample, middle Baogang sample, crystallizer steel sample and strand sample, chemical method is used to analyze total oxygen content, analysis result is shown in Fig. 1, and result shows that new coverture Adding Way effectively can prevent secondary oxidation of steel, can fully adsorb molten steel oxidation field trash again.
4.2 use the modified mouth of a river:
The structure at the mouth of a river:
Improve front mouth of a river side opening shape for oval, oval long and short shaft length is respectively 70mm, 55mm;
After improving, mouth of a river side opening shape is isosceles trapezoid, and as shown in Figure 2, the trapezoidal upper length of side is 55mm, and the lower length of side is 25mm, and height is 75mm.This trapezoidal inclination angle is 10 °, and mouth of a river side opening area and mouth of a river mesopore area ratio are 1.94.
The design at the new mouth of a river, can realize stock stable and uniform circulation in steel stream upper reaches in crystallizer, both can improve mold liquid level temperature, and can prevent liquid level slag again.
4.3 use modified stopper
The structure of stopper:
Before improving, stopper inside is provided with through hole, and this hole leads to bottom caput, and median pore diameter is 34mm, and the front median pore diameter of bottom is 5mm, and front mesopore height is 100mm, and mesopore seamlessly transits to front mesopore.
After improving, stopper inside is provided with mesopore, and median pore diameter is 34mm, and mesopore seamlessly transits to front mesopore, and front median pore diameter is 5mm, and front mesopore height is 40mm.
The present invention improves stopper head, is adjusted to solid design by former hollow design, has stopped bubble in crystallizer and has produced.
4.4 crystallizer cooling water width face water yield settings are respectively 4000L/min, 410L/min, and poring rate is set as 1.30m/min:
Described wide finger crystallizer internal and external cambered surface, corresponding with wide of strand, leptoprosopy refers to crystallizer left and right leptoprosopy, and corresponding with strand leptoprosopy, poring rate is set as 1.30m/min
Be poured and check continuous casting billet surface, surface does not find metallic particles defect, and casting billet surface is good.
After application the present invention, continuous casting billet surface metal grain defect ratio is down to 6.5%, and the moon reduces reconditioning loss amount 81 tons, and the moon reduces 180 hours reconditioning time.Monthlyly bring benefits 1,500,000 yuan, 1,800 ten thousand yuan can be brought benefits every year.
Claims (5)
1. eliminate a method for continuous casting billet surface metal grain defect, it is characterized in that:
(1) double-deck coverture is adopted
Coverture Adding Way is added by original individual layer and is adjusted to bilayer and adds, and first adds alkaline covering agent, then covers the magnesia high-melting-point coverture of a floor height thereon;
(2) primary cooling water optimization
Adopt and reduce crystallizer primary cooling water intensity method;
(3) mouth of a river is set
Adopt hydraulics experiment, exploitation updip 10 °, the trapezoidal mouth of a river of large, the V-arrangement kerve of hole area in side opening area ratio;
(4) stopper is set
Stopper head is improved, is adjusted to solid design by former hollow design.
2. the method for elimination continuous casting billet surface metal grain defect according to claim 1, it is characterized in that: the concrete operation method of described primary cooling water optimization is: crystallizer wide cooling water inflow is reduced to 4000 L/min by former 4300L/min, it is constant that crystallizer leptoprosopy cooling water inflow maintains 410L/min.
3. the method for elimination continuous casting billet surface metal grain defect according to claim 1, is characterized in that: the composition of described alkaline covering agent is: w (SiO
2): 8.0-11%; W (Al
2o
3): 25-31%; W (CaO): 42-50%; W (MgO): 3.5-7.5%; W (Na
2o) :≤1.0%; W (C): 2.5-5.0%; Basicity: 4.0-6.0.
4. the method for elimination continuous casting billet surface metal grain defect according to claim 1, is characterized in that: the structure at the described mouth of a river is mouth of a river side opening shape is isosceles trapezoid, and the trapezoidal upper length of side is 55mm, and the lower length of side is 25mm, and height is 75mm; This trapezoidal inclination angle is 10 °, and mouth of a river side opening area and mouth of a river mesopore area ratio are 1.94.
5. the method for elimination continuous casting billet surface metal grain defect according to claim 1, it is characterized in that: the structure of described stopper is that inside is provided with mesopore, and median pore diameter is 34mm, and mesopore seamlessly transits to front mesopore, front median pore diameter is 5mm, and front mesopore height is 40mm.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108637195A (en) * | 2018-04-24 | 2018-10-12 | 舞阳钢铁有限责任公司 | Prevent the continuous casting process of the nearly surface layer gas hole defect of continuous casting billet |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6117389A (en) * | 1997-09-29 | 2000-09-12 | Kawasaki Steel Corporation | Titanium killed steel sheet and method |
| CN101347823A (en) * | 2008-09-11 | 2009-01-21 | 首钢总公司 | Method for using double-layer continuous casting pouring box covering agent |
| CN101486587A (en) * | 2009-01-04 | 2009-07-22 | 攀钢集团研究院有限公司 | Double-layer tundish covering agent |
| CN101633038A (en) * | 2009-05-26 | 2010-01-27 | 山西太钢不锈钢股份有限公司 | Method for reducing surface defect of stainless steel continues casting blank |
| CN101758176A (en) * | 2010-01-21 | 2010-06-30 | 山西太钢不锈钢股份有限公司 | Double-layer tundish covering agent |
| CN102861890A (en) * | 2012-09-19 | 2013-01-09 | 中冶南方工程技术有限公司 | Secondary cooling method for reducing transverse cracks of corners of microalloy sheet billet |
-
2015
- 2015-04-09 CN CN201510163794.8A patent/CN104785737B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6117389A (en) * | 1997-09-29 | 2000-09-12 | Kawasaki Steel Corporation | Titanium killed steel sheet and method |
| CN101347823A (en) * | 2008-09-11 | 2009-01-21 | 首钢总公司 | Method for using double-layer continuous casting pouring box covering agent |
| CN101486587A (en) * | 2009-01-04 | 2009-07-22 | 攀钢集团研究院有限公司 | Double-layer tundish covering agent |
| CN101633038A (en) * | 2009-05-26 | 2010-01-27 | 山西太钢不锈钢股份有限公司 | Method for reducing surface defect of stainless steel continues casting blank |
| CN101758176A (en) * | 2010-01-21 | 2010-06-30 | 山西太钢不锈钢股份有限公司 | Double-layer tundish covering agent |
| CN102861890A (en) * | 2012-09-19 | 2013-01-09 | 中冶南方工程技术有限公司 | Secondary cooling method for reducing transverse cracks of corners of microalloy sheet billet |
Non-Patent Citations (1)
| Title |
|---|
| 白晋钢: "太钢结晶器梯形水口不同工况的水模型试验研究", 《铸造设备研究》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108637195A (en) * | 2018-04-24 | 2018-10-12 | 舞阳钢铁有限责任公司 | Prevent the continuous casting process of the nearly surface layer gas hole defect of continuous casting billet |
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| CN104785737B (en) | 2016-09-21 |
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