CN108971476B - Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof - Google Patents
Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof Download PDFInfo
- Publication number
- CN108971476B CN108971476B CN201810772207.9A CN201810772207A CN108971476B CN 108971476 B CN108971476 B CN 108971476B CN 201810772207 A CN201810772207 A CN 201810772207A CN 108971476 B CN108971476 B CN 108971476B
- Authority
- CN
- China
- Prior art keywords
- zirconium core
- blocking
- nozzle
- zirconium
- raw materials
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
- B22D41/50—Pouring-nozzles
- B22D41/52—Manufacturing or repairing thereof
- B22D41/54—Manufacturing or repairing thereof characterised by the materials used therefor
Abstract
The invention belongs to the technical field of refractory materials, and particularly relates to an anti-blocking composite zirconium core built-in submerged nozzle for special steel and a preparation process thereof, wherein the nozzle comprises an aluminum-carbon body, a zirconium-carbon slag line, a zirconium core and an anti-blocking lining, the zirconium core is arranged at the bowl part of the nozzle, the anti-blocking lining is arranged in the inner cavity of the nozzle, and the raw material composition of each part is disclosed; the invention is obtained by pressing and molding an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining, then manufacturing a zirconium core, finally embedding the zirconium core in a bowl part of a water gap through fire clay, and spraying anti-oxidation coating. The submerged nozzle of the invention not only can meet the requirement of secondary continuous casting of special steel blast furnaces, but also can improve the condition of nozzle blockage in the casting process of some special steel types.
Description
Technical Field
The invention belongs to the technical field of refractory materials, and particularly relates to an anti-blocking composite zirconium core built-in submerged nozzle for special steel and a preparation process thereof.
Background
In the production process of special steel, because the types of molten steel are complex, the difference of components and smelting process among various types of steel is large, and the traditional aluminum-carbon integral submerged nozzle can hardly completely meet the use requirement of secondary continuous casting of molten steel in a blast furnace. On some alloy structural steels, because of the addition of more alloying elements, oxides of certain alloying elements (such as MnO)2、CaO、Cr2O3Etc.) can cause abnormal erosion to the material of the integral nozzle bowl, leading to the failure of the matching between the stopper rod and the integral nozzle bowl and the failure of normal flow control. When bearing steel grades are cast, more Al, Ca and other elements are introduced in the smelting process, so that the molten steel contains more Al2O3、xCaO•yAl2O3The (calcium aluminate) inclusions can continuously move towards the inner wall of the nozzle and adhere to the inner wall of the nozzle to cause the inner hole of the nozzle to be blocked under the action of molten steel vortex in the casting process.
In recent years, in order to ensure that special steel successfully reaches the production target, refractory enterprises are continuously developing new varieties to meet the above special requirements. For example, MgO-C, MgO-Al is changed from aluminum carbon material at the bowl part of the water gap2O3-a material of C; the inner wall of the water gap is compounded with the carbon-free and silicon-free anti-blocking lining, so that the service life of the water gap has a certain promotion effect, but when the water gap is used for steel grades such as low carbon, ultra-low carbon and the like, the material can not completely reach the aimAnd (5) use requirements.
The Chinese patent application with the publication number of CN1796028A discloses an anti-blocking submerged nozzle for the continuous casting of special steel, which is provided with A12O3-a body of C material and ZrO2-C slag line with a carbon-free anti-blocking lining of a carbon-free composite of oxides and non-oxides, the oxides being corundum, spinel; the non-oxide is nitride, the nitride is silicon nitride, aluminum nitride and boron nitride, the amount of the oxide is 75-95 wt%, and the amount of the non-oxide is 5-25 wt%. The anti-blocking submerged nozzle provided by the invention reduces the reaction degree of the nozzle lining and the inclusion containing CaO, and solves the nozzle blocking phenomenon in the special steel continuous casting process during practical application. However, when Al is included as inclusions on the inner wall of the nozzle2O3When the method is mainly used, the anti-blocking effect can be achieved by reducing the reactivity of the lining material and the molten steel; when the inclusions on the inner wall of the nozzle are mixed with xCaO2O3The nozzle plugging mechanism is mainly physical adsorption, and the occurrence of plugging phenomenon cannot be inhibited by the reaction inertia of a lining material and molten steel, although the gas generated by the pyrolysis of nitride in the patent can play a role in preventing the nozzle from plugging, on one hand, because the addition amount of the nitride is limited (5-25 wt%), the partial pressure of the gas generated by the decomposition is not enough to completely isolate the contact between the molten steel and the inner wall material of the nozzle, and on the other hand, the pyrolysis temperature of the nitride (aluminum nitride and silicon nitride) is high, and the nitride is not easy to generate decomposition reaction at the use temperature of the nozzle (about 1500 ℃).
Disclosure of Invention
In order to overcome the defects, the invention aims to provide the submerged nozzle with the built-in anti-blocking composite zirconium core for the special steel and the preparation process thereof, which can not only meet the requirement of the continuous casting of the special steel in a blast furnace, but also improve the condition of nozzle blocking in the casting process of some special steel types.
In order to achieve the purpose, the invention adopts the following technical scheme:
an anti-blocking composite zirconium core built-in submersed nozzle for special steel comprises an aluminum-carbon body, a zirconium-carbon slag line, a zirconium core and an anti-blocking lining, wherein the zirconium core is embedded in a nozzle bowl part through fire clay, and the anti-blocking lining is arranged in an inner cavity of the nozzle;
the aluminum carbon body is prepared from the following raw materials in percentage by weight: 50-65% of fused brown corundum, 25-30% of flake graphite, 3-5% of metal silicon powder, 6-18% of calcined alumina powder and phenolic resin accounting for 6-11% of the total weight of the raw materials;
the zirconium carbon slag line is prepared from the following raw materials in percentage by weight: 80-86% of electrofusion-stabilized zirconia, 10-15% of flake graphite, 2-5% of metal silicon powder and 5-10% of phenolic resin in total weight of the raw materials;
the zirconium core is prepared from the following raw materials in percentage by weight: 90-96% of high-purity fused zirconia, 1-5% of yttrium oxide, 1-4% of magnesium oxide, 1-3% of calcined alumina powder and 4-10% of a bonding agent based on the total weight of the raw materials;
the anti-blocking lining is prepared from the following raw materials in percentage by weight: 65-70% of fused quartz, 20-28% of crystalline flake graphite, 1-3% of potassium feldspar, 2-5% of metal silicon powder, 2-3% of borax and phenolic resin accounting for 6-12% of the total weight of the raw materials.
Preferably, the height of the zirconium core is 50 mm-250 mm, and the volume density is 5.2-5.5 g/cm3The apparent porosity is 2-3%.
Preferably, the thickness of the fire clay is 1-3 mm.
Preferably, the binder is polyvinyl alcohol.
Preferably, the thickness of the anti-blocking lining is 3-8 mm, and the volume density is 2.2-2.4 g/cm3The apparent porosity is 10-20%.
Preferably, the fused quartz grain size is selected from 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz.
Preferably, the flake graphite is high-purity grade 99 graphite.
Preferably, the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
A preparation process of the anti-blocking composite zirconium core built-in submerged nozzle for the special steel comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing and molding the three pug materials obtained in the step (1) in a cold isostatic press;
(3) drying the blank formed in the step (2) at 200-250 ℃ for 6-10h, and then firing and forming at 800-1200 ℃;
(4) mixing zirconium core raw materials to obtain pug, naturally drying for 24-48h, pressing into a green body in a friction press, then drying at the temperature of 100-120 ℃ for 6-12h, and finally firing at the temperature of 1500-1800 ℃ for forming;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Preferably, the pressure of the cold isostatic press is 100-120 MPa, and the pressure of the friction press is 60-80 MPa.
1. According to the invention, the zirconium core is embedded in the water gap bowl part, the high-purity fused zirconia is chemically inert to various components in molten steel, and is not eroded by the molten steel in the casting process, the shape of the water gap bowl part cannot deform in the using process, and the blast furnace casting in the special steel continuous casting process is ensured; the composite stabilizer is composed of yttrium oxide and magnesium oxide, secondary stabilization is carried out on high-purity electric melting zirconium oxide in the sintering process, meanwhile, the sintering temperature of a zirconium core can be reduced to a certain degree due to the addition of magnesium oxide and calcined alumina powder, and polyvinyl alcohol is used as a temporary bonding agent and becomes gas to volatilize after high-temperature oxidation. The zirconium core has the synergistic effect of the raw materials, and the volume density of the obtained zirconium core is 5.2-5.5 g/cm3The apparent porosity is 2-3%, the zirconium core is good in compactness, high in stability and long in service life.
2. The particle size of the anti-blocking lining fused quartz is selected from 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total weight of the fused quartz, the crystalline flake graphite is 99-grade high-purity graphite, and the carbothermic reduction reaction activity is high. When in use, the surface temperature of the lining material can reach more than 1500 ℃, and the fused quartz (SiO)2) The carbon thermal reduction reaction is carried out on the graphite and the resin carbon to generate a large amount of SiO and CO gas for blockingThe molten steel is in direct contact with the inner wall of the water gap, and the adhesion of impurities on the inner wall of the water gap is effectively prevented. Meanwhile, potassium feldspar and borax low-melting-point substances are further filled with some unsealed pores after being melted at high temperature, so that the adsorption of inclusions in molten steel on lining materials is further avoided, and the metal silicon powder improves the high-temperature strength of the anti-blocking lining and prevents the anti-blocking lining from being oxidized. The volume density of the anti-blocking lining is 2.2-2.4 g/cm3The apparent porosity is 10-20%, and the adhesion of impurities on the inner wall of the water gap can be effectively prevented.
3. The invention can not only meet the requirement of the special steel blast furnace secondary continuous casting, but also improve the condition of water gap blockage in the casting process of some special steel types, and has long service life.
Drawings
FIG. 1 is a schematic structural view of an anti-blocking composite zirconium core with an embedded submerged nozzle for special steel of the present invention;
in the figure, 1-aluminum carbon body, 2-zirconium carbon slag line, 3-zirconium core and 4-anti-blocking lining.
Detailed Description
The invention will be further illustrated with reference to some specific examples.
Example 1
Referring to fig. 1, the anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum-carbon body 1, a zirconium-carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 60% of fused brown corundum, 25% of flake graphite, 5% of metal silicon powder, 10% of calcined alumina powder and phenolic resin accounting for 6% of the total weight of the raw materials;
zirconium carbon slag line component: 85% of electrofusion-stabilized zirconia, 12% of flake graphite, 3% of metal silicon powder and 8% of phenolic resin in total weight of the added raw materials;
zirconium core component: 95% of high-purity fused zirconia, 3% of yttrium oxide, 1% of magnesium oxide, 1% of calcined alumina powder and polyvinyl alcohol accounting for 4% of the total weight of the raw materials.
Anti-blocking lining components: 65% of fused quartz, 25% of crystalline flake graphite, 3% of potassium feldspar, 4% of metal silicon powder, 3% of borax and 12% of phenolic resin in total weight of the added raw materials.
The height of the zirconium core is 250mm, and the volume density is 5.2g/cm3The apparent porosity was 3%.
The thickness of the fire clay is 1 mm.
The thickness of the anti-blocking lining is 8mm, and the volume density is 2.2g/cm3The apparent porosity was 10%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 105 MPa;
(3) drying the blank formed in the step (2) at 220 ℃ for 6h, and then firing and forming at 1000 ℃;
(4) mixing the zirconium core raw materials to obtain pug, naturally drying for 24h, pressing into a green body in a friction press under the pressure of 60MPa, then drying for 10h at 100 ℃, and finally firing and molding at 1600 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Example 2
An anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum carbon body 1, a zirconium carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 50% of fused brown corundum, 29% of flake graphite, 3% of metal silicon powder, 18% of calcined alumina powder and 11% of phenolic resin in total weight of the raw materials;
zirconium carbon slag line component: 80% of electrofusion-stabilized zirconia, 15% of flake graphite, 5% of metal silicon powder and 9% of phenolic resin in total weight of the raw materials;
zirconium core component: 94% of high-purity fused zirconia, 2% of yttrium oxide, 2.5% of magnesium oxide, 1.5% of calcined alumina powder and polyvinyl alcohol accounting for 4% of the total weight of the raw materials;
anti-blocking lining components: 70% of fused quartz, 20% of crystalline flake graphite, 2% of potassium feldspar, 5% of metal silicon powder, 3% of borax and 11% of phenolic resin in total weight of the added raw materials.
The height of the zirconium core is 100mm, and the volume density is 5.3g/cm3The apparent porosity was 3%.
The thickness of the fire clay is 2 mm.
The thickness of the anti-blocking lining is 3mm, and the volume density is 2.3g/cm3The apparent porosity was 20%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 110 MPa;
(3) drying the blank formed in the step (2) at 200 ℃ for 10h, and then firing and forming at 1100 ℃;
(4) mixing zirconium core raw materials to obtain pug, naturally drying for 48h, pressing into a green body in a friction press under the pressure of 70MPa, then drying for 10h at 110 ℃, and finally firing and molding at 1500 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Example 3
An anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum carbon body 1, a zirconium carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 65% of fused brown corundum, 25% of flake graphite, 4% of metal silicon powder, 6% of calcined alumina powder and 10% of phenolic resin in total weight of the raw materials;
zirconium carbon slag line component: 86% of electrofusion-stabilized zirconia, 12% of flake graphite, 2% of metal silicon powder and 9% of phenolic resin in total weight of additional raw materials;
zirconium core component: 96% of high-purity fused zirconia, 1% of yttrium oxide, 2% of magnesium oxide, 1% of calcined alumina powder and polyvinyl alcohol accounting for 4% of the total weight of the raw materials;
anti-blocking lining components: 63% of fused quartz, 28% of crystalline flake graphite, 3% of potassium feldspar, 4% of metal silicon powder, 2% of borax and 12% of phenolic resin in total weight of the additional raw materials.
The height of the zirconium core is 200mm, and the volume density is 5.3g/cm3The apparent porosity was 2%.
The thickness of the fire clay is 3 mm.
The thickness of the anti-blocking lining is 5mm, and the volume density is 2.4g/cm3The apparent porosity was 12%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 100 MPa;
(3) drying the blank formed in the step (2) at 230 ℃ for 8h, and then firing and forming at 1200 ℃;
(4) mixing zirconium core raw materials to obtain pug, naturally drying for 36h, pressing into a green body in a friction press under the pressure of 80MPa, then drying for 6h at 120 ℃, and finally firing and molding at 1800 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Example 4
An anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum carbon body 1, a zirconium carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 50% of fused brown corundum, 30% of flake graphite, 4% of metal silicon powder, 18% of calcined alumina powder and 8% of phenolic resin in total weight of the raw materials;
zirconium carbon slag line component: 85% of electrofusion-stabilized zirconia, 10% of flake graphite, 5% of metal silicon powder and 10% of phenolic resin of the total weight of the additional raw materials;
zirconium core component: 93% of high-purity fused zirconia, 2.5% of yttrium oxide, 2.5% of magnesium oxide, 2% of calcined alumina powder and polyvinyl alcohol accounting for 6% of the total weight of the raw materials.
Anti-blocking lining components: 66% of fused quartz, 28% of crystalline flake graphite, 2% of potassium feldspar, 2% of metal silicon powder, 2% of borax and 10% of phenolic resin in total weight of the added raw materials.
The height of the zirconium core is 50mm, and the volume density is 5.3g/cm3The apparent porosity was 2.2%.
The thickness of the fire clay is 1 mm.
The thickness of the anti-blocking lining is 6mm, and the volume density is 2.3g/cm3The apparent porosity was 15%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 105 MPa;
(3) drying the blank formed in the step (2) at 250 ℃ for 6h, and then firing and forming at 800 ℃;
(4) mixing the zirconium core raw materials to obtain pug, naturally drying for 24h, pressing into a green body in a friction press, wherein the pressure is 70MPa, then drying for 12h at 100 ℃, and finally firing and molding at 1600 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Example 5
An anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum carbon body 1, a zirconium carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 55% of fused brown corundum, 30% of flake graphite, 5% of metal silicon powder, 10% of calcined alumina powder and 8% of phenolic resin in total weight of the raw materials;
zirconium carbon slag line component: 82% of electrofusion-stabilized zirconia, 14% of flake graphite, 4% of metal silicon powder and 5% of phenolic resin in total weight of the raw materials;
zirconium core component: 90% of high-purity fused zirconia, 5% of yttrium oxide, 2% of magnesium oxide, 3% of calcined alumina powder and polyvinyl alcohol accounting for 8% of the total weight of the raw materials.
Anti-blocking lining components: 68% of fused quartz, 23% of crystalline flake graphite, 1% of potassium feldspar, 5% of metal silicon powder, 3% of borax and 8% of phenolic resin in total weight of the added raw materials.
The height of the zirconium core is 150mm, and the volume density is 5.4g/cm3The apparent porosity was 2.5%.
The thickness of the fire clay is 2 mm.
The anti-blockingThe thickness of the lining is 7mm, and the volume density is 2.3g/cm3The apparent porosity was 16%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 105 MPa;
(3) drying the blank formed in the step (2) at 240 ℃ for 8h, and then firing and forming at 1000 ℃;
(4) mixing the zirconium core raw materials to obtain pug, naturally drying for 24h, pressing into a green body in a friction press under the pressure of 60MPa, then drying for 10h at 100 ℃, and finally firing and molding at 1600 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Example 6
An anti-blocking composite zirconium core built-in submerged nozzle for special steel comprises an aluminum carbon body 1, a zirconium carbon slag line 2, a zirconium core 3 and an anti-blocking lining 4, wherein the zirconium core 3 is embedded in a nozzle bowl through fire clay, and the anti-blocking lining 4 is arranged in an inner cavity of the nozzle;
aluminum carbonaceous bulk composition: 62% of fused brown corundum, 27% of flake graphite, 4% of metal silicon powder, 7% of calcined alumina powder and 10% of phenolic resin in total weight of the raw materials;
zirconium carbon slag line component: 83% of electrofusion-stabilized zirconia, 12% of flake graphite, 5% of metal silicon powder and phenolic resin accounting for 10% of the total weight of the raw materials;
zirconium core component: 92% of high-purity fused zirconia, 2% of yttrium oxide, 4% of magnesium oxide, 2% of calcined alumina powder and polyvinyl alcohol accounting for 10% of the total weight of the raw materials;
anti-blocking lining components: 70% of fused quartz, 21% of crystalline flake graphite, 2% of potassium feldspar, 4% of metal silicon powder, 3% of borax and 6% of phenolic resin in total weight of the added raw materials.
The height of the zirconium core is 250mm, and the volume density is 5.5g/cm3The apparent porosity was 2.3%.
The thickness of the fire clay is 2 mm.
The thickness of the anti-blocking lining is 8mm, and the volume density is 2.3g/cm3The apparent porosity was 15%.
The particle size fraction of the fused quartz is 0.5-0.2mm, 0.2-0mm and 325 meshes, wherein the 325 meshes account for more than 50% of the total fused quartz; the flake graphite is 99-grade high-purity graphite; the particle sizes of the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes.
The preparation process of the nozzle comprises the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing the three pugs obtained in the step (1) into a mold in a cold isostatic press, wherein the pressure is 110 MPa;
(3) drying the blank formed in the step (2) at 200 ℃ for 10h, and then firing and forming at 1000 ℃;
(4) mixing zirconium core raw materials to obtain pug, naturally drying for 28h, pressing into a green body in a friction press under the pressure of 80MPa, then drying for 8h at 110 ℃, and finally firing and molding at 1800 ℃;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
Application test
The application test is carried out on a special steel production line of a first steel mill of Henan Jiyuan iron and steel Limited company, 7 nozzles of the invention or 7 comparative tests are placed in a tundish, MgO-C bowl mouths and carbon-free spinel linings are adopted in the comparative tests, the test steel types comprise 40Cr, 20MnTiB, 60Si2Mn, GCr15 and the like, and the test results are as follows:
40 Cr: the nozzle of the invention reaches 22 furnaces for continuous casting, the rod position of the stopper rod does not drop, and the use process is not abnormal; the comparative test reaches 18 continuous casting furnaces, the average rod position of the stopper rod is reduced by 20mm, and the stopper rod cannot be used continuously.
20 MnTiB: the water gap of the invention reaches 13 furnaces for continuous casting, no abnormity occurs in the using process, and no obvious impurity deposition exists on the inner wall; the comparative test reaches 13 continuous casting furnaces, and the average deposition of inclusions on the inner wall is 2 mm.
60Si2 Mn: the water gap of the invention reaches 13 furnaces for continuous casting, no abnormity occurs in the using process, and no obvious impurity deposition exists on the inner wall; the comparative test reaches 13 continuous casting furnaces, and the average deposition of inclusions on the inner wall is 1 mm.
GCr 15: the water gap of the invention reaches 8 furnaces for continuous casting, no abnormity occurs in the using process, and the inclusions on the inner wall are deposited by 2mm on average; in a contrast test, when the water gap is blocked when the continuous casting is carried out to 5 furnaces, the inner wall inclusions are deposited by 4mm on average.
From the above it is evident that: compared with the traditional water gap using process, in the steel casting process of the water gap, the water gap bowl is reinforced by the zirconium core, so that the water gap bowl is not easily corroded by molten steel, and the stopper rod position does not fall in the whole process; the inner wall of the water gap adopts SiO2the-C anti-blocking lining is enhanced, no obvious impurity deposition exists on the inner wall, the using effect is obviously superior to that of the traditional nozzle, and the service life of the nozzle is obviously prolonged.
Finally, the above embodiments are only used for illustrating the technical solutions of the present invention and not for limiting, and other modifications or equivalent substitutions made by the technical solutions of the present invention by those of ordinary skill in the art should be covered within the scope of the claims of the present invention as long as they do not depart from the spirit and scope of the technical solutions of the present invention.
Claims (9)
1. An anti-blocking composite zirconium core built-in submerged nozzle for special steel is characterized by comprising an aluminum-carbon body, a zirconium-carbon slag line, a zirconium core and an anti-blocking lining, wherein the zirconium core is embedded in a nozzle bowl through fire clay, and the anti-blocking lining is arranged in an inner cavity of the nozzle;
the aluminum carbon body is prepared from the following raw materials in percentage by weight: 50-65% of fused brown corundum, 25-30% of flake graphite, 3-5% of metal silicon powder, 6-18% of calcined alumina powder and phenolic resin accounting for 6-11% of the total weight of the raw materials;
the zirconium carbon slag line is prepared from the following raw materials in percentage by weight: 80-86% of electrofusion-stabilized zirconia, 10-15% of flake graphite, 2-5% of metal silicon powder and 5-10% of phenolic resin in total weight of the raw materials;
the zirconium core is prepared from the following raw materials in percentage by weight: 90-96% of high-purity fused zirconia, 1-5% of yttrium oxide, 1-4% of magnesium oxide, 1-3% of calcined alumina powder and 4-10% of a bonding agent based on the total weight of the raw materials;
the anti-blocking lining is prepared from the following raw materials in percentage by weight: 65-70% of fused quartz, 20-28% of crystalline flake graphite, 1-3% of potassium feldspar, 2-5% of metal silicon powder, 2-3% of borax and phenolic resin accounting for 6-12% of the total weight of the raw materials.
2. The anti-blocking composite zirconium core built-in submerged nozzle for special steel as claimed in claim 1, wherein the zirconium core has a height of 50mm to 250mm and a bulk density of 5.2 to 5.5g/cm3The apparent porosity is 2-3%.
3. The anti-blocking composite zirconium core built-in submerged nozzle for special steel as claimed in claim 1, wherein the thickness of the fire clay is 1-3 mm.
4. The anti-clogging composite zirconium core built-in submerged nozzle for special steel as claimed in claim 1, wherein the binder is polyvinyl alcohol.
5. The anti-blocking composite zirconium core built-in submerged nozzle for special steel as claimed in claim 1, wherein the thickness of the anti-blocking lining is 3-8 mm, and the bulk density is 2.2-2.4 g/cm3The apparent porosity is 10-20%.
6. The anti-blocking composite zirconium core built-in submerged nozzle for the special steel as claimed in claim 1, wherein the scale graphite is 99-grade high-purity graphite.
7. The anti-blocking composite zirconium core built-in submerged nozzle for the special steel as claimed in claim 1, wherein the potassium feldspar, the metal silicon powder and the borax are respectively 150-300 meshes in particle size.
8. A preparation process of the submerged nozzle with the anti-blocking composite zirconium core for the special steel as claimed in claim 1 is characterized by comprising the following steps:
(1) firstly, respectively mixing raw materials of an aluminum-carbon body, a zirconium-carbon slag line and an anti-blocking lining in a granulator to obtain three pugs, and drying;
(2) pressing and molding the three pug materials obtained in the step (1) in a cold isostatic press;
(3) drying the blank formed in the step (2) at 200-250 ℃ for 6-10h, and then firing and forming at 800-1200 ℃;
(4) mixing zirconium core raw materials to obtain pug, naturally drying for 24-48h, pressing into a green body in a friction press, then drying at the temperature of 100-120 ℃ for 6-12h, and finally firing at the temperature of 1500-1800 ℃ for forming;
(5) embedding the zirconium core fired and formed in the step (4) into the bowl part of the semi-finished nozzle obtained in the step (3) through fire clay;
(6) and (5) spraying an anti-oxidation coating on the water gap in the step (5) to obtain the water gap.
9. The preparation process of the submerged nozzle with the anti-blocking composite zirconium core for special steel according to claim 8, wherein the pressure of the cold isostatic press is 100-110 MPa, and the pressure of the friction press is 60-80 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810772207.9A CN108971476B (en) | 2018-07-13 | 2018-07-13 | Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810772207.9A CN108971476B (en) | 2018-07-13 | 2018-07-13 | Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108971476A CN108971476A (en) | 2018-12-11 |
| CN108971476B true CN108971476B (en) | 2020-05-22 |
Family
ID=64537591
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810772207.9A Active CN108971476B (en) | 2018-07-13 | 2018-07-13 | Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108971476B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110918970B (en) * | 2019-11-15 | 2021-06-25 | 中天钢铁集团有限公司 | Submerged nozzle lining material for reducing wire breakage rate in silicon-deoxidized steel processing process |
| CN111531160B (en) * | 2020-06-16 | 2021-08-17 | 江苏兴湖耐火材料有限公司 | Method for manufacturing corrosion-resistant long nozzle for continuous casting |
| CN115160000B (en) * | 2022-07-06 | 2023-03-14 | 青岛正望新材料股份有限公司 | Composite pug for producing functional refractory material for steelmaking and preparation method and application thereof |
| CN116199509A (en) * | 2023-02-08 | 2023-06-02 | 江苏泰瑞耐火有限公司 | Toughened zirconia ceramic tundish nozzle for continuous casting of slabs, large square billets and rectangular billets and production process thereof |
| CN117226083B (en) * | 2023-11-14 | 2024-01-26 | 山西昊业新材料开发有限公司 | Long nozzle for continuous casting and preparation method thereof |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55165274A (en) * | 1979-06-09 | 1980-12-23 | Kurosaki Refract Co Ltd | Molten metal injection nozzle |
| CN1796028A (en) * | 2004-12-24 | 2006-07-05 | 中钢集团洛阳耐火材料研究院 | Anti sealed immersion nozzle in use for continuous casting specific steel |
| CN102335730B (en) * | 2010-07-26 | 2013-07-17 | 宝山钢铁股份有限公司 | Silicone-free submersed nozzle and manufacturing method thereof |
| CN103880453B (en) * | 2014-03-28 | 2015-11-04 | 无锡市南方耐材有限公司 | Continuous casting functional mouth of a river material and preparation method thereof |
| KR101639753B1 (en) * | 2014-11-18 | 2016-07-14 | 주식회사 포스코 | Nozzle and manufacturing method of the same |
-
2018
- 2018-07-13 CN CN201810772207.9A patent/CN108971476B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108971476A (en) | 2018-12-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108971476B (en) | Anti-blocking composite zirconium core built-in submerged nozzle for special steel and preparation process thereof | |
| US10207955B2 (en) | Refractories and use thereof | |
| CN107032810B (en) | Gunning mix with excellent bonding performance for sintering large flue and preparation method | |
| CN106145964B (en) | Dry ramming material for large ladle bottom working lining | |
| CN113072364A (en) | Lightweight refractory castable for blast furnace swinging chute and preparation method thereof | |
| US20180016191A1 (en) | Refractories and use thereof | |
| CN113233908A (en) | Regenerated carbon-free brick and preparation method thereof | |
| CN113603466A (en) | Steel ladle aluminum magnesium refractory mortar for recycling refractory dust-absorbing powder and preparation method thereof | |
| CN109422537A (en) | Continuous casting is with exempting to toast refractory material and preparation method thereof | |
| CN104972103A (en) | Combined type steel ladle permanent layer casting body | |
| CN103467119A (en) | Preparation method for microporous alumina carbon brick | |
| CN110526689B (en) | High-strength blast furnace taphole channel prefabricated part and preparation method thereof | |
| CN112645698A (en) | Aluminum titanium silicon carbide composite refractory castable for iron-making blast furnace | |
| CN116967438A (en) | Continuous casting steel ladle anti-bursting long nozzle and preparation method thereof | |
| CN111995405A (en) | High-temperature-resistant heat-preservation permanent lining for steel ladle | |
| JP4546934B2 (en) | Manufacturing method of irregular refractories using refractories after use | |
| CN115108842B (en) | Long nozzle for high-oxygen steel continuous casting | |
| CN113461411B (en) | Oxidation-resistant aluminum silicon carbide carbon brick and preparation method thereof | |
| CN111113636B (en) | Preparation method of tundish turbulence controller for low-cost long-service-life continuous casting of special-shaped blank and tundish turbulence controller prepared by preparation method | |
| CN114478031A (en) | Production process of unburned aluminum-magnesia-carbon brick for electric furnace steel ladle | |
| CN114804823A (en) | Heat-insulating refractory material for air supply device of iron-making blast furnace | |
| CN111113633A (en) | Novel special-shaped blank tundish turbulence controller and preparation method thereof | |
| CN102336573B (en) | Aluminum titanate-sialon-silicon carbide composite molten steel feeding port, and manufacturing method thereof | |
| JP2009242122A (en) | Brick for blast furnace hearth and blast furnace hearth lined with the same | |
| CN111113637A (en) | Combined special-shaped blank continuous casting tundish turbulence controller and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |