WO2017090819A1 - Nozzle, casting device, and casting method - Google Patents

Nozzle, casting device, and casting method Download PDF

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Publication number
WO2017090819A1
WO2017090819A1 PCT/KR2015/014134 KR2015014134W WO2017090819A1 WO 2017090819 A1 WO2017090819 A1 WO 2017090819A1 KR 2015014134 W KR2015014134 W KR 2015014134W WO 2017090819 A1 WO2017090819 A1 WO 2017090819A1
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WO
WIPO (PCT)
Prior art keywords
nozzle
molten steel
liner
nozzle body
casting
Prior art date
Application number
PCT/KR2015/014134
Other languages
French (fr)
Korean (ko)
Inventor
김욱
Original Assignee
주식회사 포스코
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Priority claimed from KR1020150167725A external-priority patent/KR101834419B1/en
Priority claimed from KR1020150167722A external-priority patent/KR101825133B1/en
Application filed by 주식회사 포스코 filed Critical 주식회사 포스코
Priority to JP2018526083A priority Critical patent/JP6582132B2/en
Priority to CN201580084876.1A priority patent/CN108778568B/en
Priority to EP15909368.1A priority patent/EP3381587B1/en
Publication of WO2017090819A1 publication Critical patent/WO2017090819A1/en

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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
    • 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
    • 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
    • B22D11/16—Controlling or regulating processes or operations
    • 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
    • B22D41/14—Closures
    • B22D41/22—Closures sliding-gate type, i.e. having a fixed plate and a movable plate in sliding contact with each other for selective registry of their openings
    • B22D41/24—Closures sliding-gate type, i.e. having a fixed plate and a movable plate in sliding contact with each other for selective registry of their openings characterised by a rectilinearly movable plate
    • 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
    • B22D41/505—Rings, inserts or other means preventing external nozzle erosion by the slag

Definitions

  • the present invention relates to a nozzle, a casting apparatus, and a casting method, and more particularly, to a nozzle, a casting apparatus, and a casting method capable of suppressing clogging through an electrochemical deoxidation reaction.
  • the continuous casting process is a process in which a ladle containing refined molten steel is placed in a continuous casting apparatus, and the liquid molten steel moves from a ladle to a mold through a tundish and turns into a solid cast. to be. At this time, the immersion nozzle is located in the lower tundish to move the molten steel from the tundish to the mold, immersed in the molten steel is in contact with the molten steel for a long time is required for excellent durability.
  • Immersion nozzle is usually excellent in corrosion resistance of alumina to the refractory and the molten metal (Al 2 O 3) and inclusions were ever amount small wettability expansion with respect to (slag composition) Al 2 O 3 a combination of good thermal conductivity of graphite (C) It is made of -C material.
  • the immersion nozzle is a cylindrical refractory serving as a flow path for supplying molten steel of the tundish to the mold.
  • a clogging layer grows from the nozzle inner wall toward the nozzle center due to a drop in temperature, an interfacial reaction at the interface between the molten steel and the nozzle inner wall, and adhesion of the nozzle inner wall of the inclusions in the molten steel.
  • Such nozzle clogging may cause a short circuit in the continuous casting process, which may adversely affect productivity and cast quality.
  • an inert gas is supplied to the molten steel from inside the nozzle to prevent the adhesion of inclusions by bubbles, and a porous type immersion nozzle is reacted with aluminum oxide, which is a representative oxide causing the nozzle clogging.
  • Efforts are being made to reduce nozzle clogging by introducing refractory materials that prevent melting of the nozzle clogging layer with the nozzle material by introducing refractory forming the melting point compound and refractory material that suppresses attachment of inclusions or contact with molten steel. have.
  • the present invention provides a nozzle, a casting apparatus and a casting method that can suppress the clogging phenomenon by causing an electrochemical deoxidation reaction during casting.
  • the present invention provides a nozzle, casting apparatus and casting method that can improve the casting process efficiency and productivity.
  • the nozzle body has an internal hole to which the molten steel can move, the discharge hole through which the molten steel can move to the outside of the inner hole; And a liner surrounding at least a portion of the inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ).
  • MgO stabilized ZrO 2 magnesia stabilized zirconia
  • the nozzle body may include Al 2 O 3 , and the nozzle body may contain 20 wt% to 30 wt% of a carbon component based on the total weight of the nozzle body.
  • the liner may comprise 80 to 95% by weight of magnesia stabilized zirconia and 5 to 20% by weight of carbon.
  • the magnesia stabilized zirconia may contain 8 to 15 mol% of magnesia (MgO).
  • a dummy ring may be provided on at least one of an upper side and a lower side of the liner with respect to the length direction of the liner.
  • the dummy ring may include a carbon component.
  • the dummy ring may be formed to have a length of 1 to 2% with respect to the length of the liner.
  • a casting apparatus according to an embodiment of the present invention, a casting device, and a tundish is accommodated therein molten steel;
  • An immersion nozzle connected to the tundish and including a nozzle body and a liner including at least a portion of an inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ);
  • a power supply unit configured to energize the molten steel accommodated in the tundish and the nozzle body. It may include.
  • the nozzle body may include Al 2 O 3 , and the nozzle body may contain 20 wt% to 30 wt% of a carbon component based on the total weight of the nozzle body.
  • the liner may comprise 80 to 95% by weight of magnesia stabilized zirconia and 5 to 20% by weight of carbon.
  • the magnesia stabilized zirconia may contain 8 to 15 mol% of magnesia (MgO).
  • a dummy ring may be provided on at least one of an upper side and a lower side of the liner with respect to the length direction of the liner.
  • the dummy ring may include a carbon component.
  • the dummy ring may be formed to have a length of 1 to 2% with respect to the length of the liner.
  • the electrode may be immersed in the molten steel in the tundish, and the power supply unit may apply power to the electrode and the immersion nozzle.
  • a casting method is a casting method of casting a cast steel by injecting molten steel contained in a tundish into a mold through an immersion nozzle, wherein the immersion nozzle comprises a nozzle body connected to the tundish, and the nozzle body.
  • a liner is provided on the inner wall and contains magnesia stabilized zirconia, and the molten steel and the nozzle body are energized to discharge oxygen contained in the molten steel to the immersion nozzle side.
  • the metal oxide generated in the molten steel is decomposed into oxygen ions and cations, and the oxygen ions are moved to the nozzle body through the liner so that oxygen in the molten steel is discharged to the immersion nozzle side.
  • the molten steel may be supplied with a cathode and the immersion nozzle as an anode.
  • the immersion nozzle may be energized so that a current density of 0.1 to 10mA / cm2.
  • At least one of upper and lower sides of the liner is provided with a dummy ring, and the dummy ring may be dissolved in the process of casting the cast to form a space.
  • the nozzle, the casting apparatus, and the casting method according to the present invention can suppress or prevent a phenomenon in which the internal air portion of the nozzle, for example, the immersion nozzle used in the casting step, is blocked. That is, a metal oxide or the like is formed on the inner wall of the immersion nozzle in contact with the molten steel during casting by forming a liner by using a solid electrolyte that enables electrochemical deoxidation to the nozzle internal hole in contact with the molten steel at the casting temperature and energizing the immersion nozzle with molten steel. It is possible to suppress or prevent the occurrence of clogging due to stacking of inclusions.
  • the concentration of interfacial oxygen in the nozzle inner wall can be reduced to reduce the wettability between the nozzle inner wall and the molten steel. Therefore, the inclusions and the wettability of the molten steel are improved in the nozzle inner cavity, which is the main factor causing the nozzle clogging, thereby preventing or preventing the nozzle from clogging.
  • This can solve the problems, such as interruption of the casting due to clogging the nozzle can improve the casting efficiency and productivity, it is possible to improve the quality of the cast produced using this. In addition, it is possible to reduce the time and cost of nozzle replacement by improving the life of the nozzle.
  • the liner is formed using a solid electrolyte having excellent ion conductivity in the immersion nozzle, power consumption for suppressing inclusion generation may be reduced.
  • FIG. 1 is a schematic view of a casting apparatus according to an embodiment of the present invention.
  • FIG 2 is a cross-sectional view of a nozzle applied to the casting apparatus according to the embodiment of the present invention.
  • Figure 3 is a schematic diagram of the deoxidation reaction occurring in the inner cavity of the nozzle during casting.
  • FIG. 4 is a cross-sectional view showing a change in the nozzle internal structure during casting.
  • FIG. 1 is a schematic view of a casting apparatus according to an embodiment of the present invention
  • Figure 2 is a cross-sectional view of a nozzle applied to the casting apparatus according to an embodiment of the present invention
  • Figure 3 is a deoxidation reaction occurring in the inner hole of the nozzle during casting It is a schematic diagram
  • FIG. 4 is sectional drawing which shows the change of the nozzle internal structure during casting.
  • a casting apparatus such as a continuous casting apparatus, includes a tundish 10 and a molten steel 60 that serve to store and distribute the molten steel 60 from a ladle, which is a vessel containing refined molten steel.
  • Mold 50 for solidifying the stopper 20 and the sliding plate 30 for controlling the flow rate
  • the immersion nozzle 40 for discharging the molten steel 60 into the mold 50 and the molten steel 60 to form a cast steel 61. It may include.
  • the stopper 20 and the sliding plate 30 are simultaneously provided to control the flow rate of the molten steel. However, any one of the stopper 20 and the sliding plate 30 may be used in actual operation. have.
  • the casting apparatus may include a power supply unit 70 for applying a voltage to the molten steel in the tundish 10 and the immersion nozzle 40.
  • the immersion nozzle 40 has an internal hole through which molten steel can move, a nozzle body 41 including a discharge port 42 through which molten steel can move outward, for example, into a mold, and a nozzle body 41.
  • the inner wall may be provided and includes a liner 43 which contains a magnesia-stabilized zirconia (MgO stabilized ZrO 2, MSZ) so as to surround at least a portion of.
  • the immersion nozzle 40 may include a slag line portion 47 surrounding at least a portion of the outer wall of the nozzle body 41.
  • the nozzle body 41 may be formed in a cylindrical shape having at least an upper portion open so as to have an inner cavity through which molten steel can move.
  • a discharge port 42 through which molten steel may be discharged from the inner cavity to the outside may be formed at the lower side of the nozzle body 41.
  • the nozzle body 41 may be formed using Al 2 O 3 -C. At this time, the nozzle body 41 may be formed to include about 20 to 30% by weight of the C component to have conductivity. This is for forming an energization circuit between the immersion nozzle 40 and the molten steel flowing along the immersion nozzle 40.
  • the liner 43 may be formed on the inner wall of the nozzle body 41, that is, the surface in contact with the molten steel.
  • the liner 43 may be formed over the entire inner wall of the nozzle body 41, but may be formed from the upper side of the nozzle body 41 to the upper portion of the discharge port 42. Accordingly, the liner 43 may be formed in a hollow cylindrical shape in which the vertical direction is opened along the inner wall of the nozzle body 41 in the nozzle body 41.
  • the liner 43 is formed on the inner wall of the nozzle body 41 to move oxygen ions in the molten steel toward the nozzle body 41.
  • the liner 43 may be formed of magnesia stabilized zirconia (MSZ), which is well known as a material having excellent ion conductivity.
  • MSZ magnesia stabilized zirconia
  • Magnesia stabilized zirconia is a solid electrolyte having a property of ions guiding electricity in a solid state, and has been applied to a solid fuel cell, a probe for measuring the concentration of oxygen in molten metal, and the like.
  • magnesia stabilized zirconia is used as the liner 43 to guide oxygen ions in the molten steel toward the nozzle body 41, so that inclusions such as SiO 2 , Al 2 O 3 , TiO 2 Generation of metal oxides such as these can be suppressed or prevented.
  • Oxygen contained in the molten steel during casting generates metal oxide at the interface between the molten steel and the inner wall of the immersion nozzle 40 due to the property of being activated at the interface.
  • the metal oxide thus produced has a high interfacial energy with molten steel and spontaneously moves to and adheres to the inner wall of the immersion nozzle 40 in the molten steel. As this process is repeated and continued, a nozzle clogging phenomenon occurs in which the inner cavity of the immersion nozzle 40 is blocked.
  • the liner 43 is formed on the inner wall of the nozzle body 41 by using a solid electrolyte having excellent ion conductivity, and the molten steel and the immersion nozzle 40, that is, the nozzle body 41 are energized to carry oxygen ions out of the molten steel. It is possible to suppress or prevent the adhesion of the metal oxide to the inner wall of the immersion nozzle 40 by guiding to.
  • the mechanism for suppressing the formation and adhesion of metal oxides is as follows.
  • oxygen contained in molten steel during casting forms a metal oxide and moves to the inner wall of the nozzle body 41.
  • FIG. 3B when the molten steel and the nozzle body 41 are energized, electrons concentrated around the metal oxide decompose the metal oxide into oxygen ions and cations (metal ions).
  • the decomposed oxygen ions are moved toward the nozzle body through the liner 43 having excellent ion conductivity, as shown in FIG. 3 (c), and escapes through the pores of the nozzle body to generate oxygen gas and discharge to the outside. do.
  • cations are absorbed into the molten steel. This process, that is, by deoxidizing the oxygen in the molten steel to the outside of the molten steel by suppressing the generation and adhesion of the metal oxide in the immersion nozzle 40 it is possible to suppress or prevent the nozzle clogging phenomenon.
  • the liner 43 may include 80 to 95 wt% of magnesia stabilized zirconia (MSZ) and 5 to 20 wt% of carbon based on the total weight of the liner 43.
  • magnesia stabilized zirconia (MSZ) may be composed of magnesia (MgO) of about 8 to 15 mol%, and the rest of the zirconia (ZrO 2 ) in order to suppress the volume change caused by the phase change according to the temperature change.
  • MgO magnesia
  • ZrO 2 the rest of the zirconia
  • the thermal expansion coefficients of the liner 43 and the nozzle body 41 are different from each other, and the thermal expansion coefficient of the liner 43 is larger than that of the nozzle body 41, so that the liner 43 is formed by volume expansion of the liner 43 during casting. Stress may act between the 43 and the nozzle body 41 to cause a crack or breakage in the liner 43.
  • the dummy ring 45 may be formed on at least one of the upper side and the lower side with respect to the longitudinal direction of the liner 43 in order to secure a space due to the volume expansion of the liner 43.
  • the dummy ring 45 may be formed to have a length of about 1 to 2% of the length of the liner 43. If the length of the dummy ring 45 is smaller than the indicated range, it is impossible to adequately cope with the volume expansion of the liner 43 so that breakage of the liner 43 is inevitable, and the length of the dummy ring 45 is larger than the indicated range. In this case, the nozzle body 41 may be exposed to molten steel to generate and attach a metal oxide.
  • the dummy ring 45 does not need to be formed if the space according to the volume expansion of the liner 43 can be secured, but it is difficult to secure the space corresponding to the volume expansion of the liner 43 due to the manufacturing characteristics of the immersion nozzle 40. Because it is inevitably formed. That is, the process of manufacturing the immersion nozzle 40 includes a pressure molding process and a firing process after injecting the raw material constituting the immersion nozzle 40 into the molding die, and when the raw material is injected into the molding die, that is, a liner This is because it is difficult to secure a space corresponding to the volume expansion of (43). Accordingly, the dummy ring 45 may be formed using a material having a lower melting point than the components constituting the liner 43.
  • the dummy ring 45 is formed on either of the upper side and the lower side of the liner 43 at the time of manufacturing the immersion nozzle 40, but during casting, the dummy ring 45 is dissolved and removed by the heat of molten steel to thereby increase the volume expansion of the liner 43. You can make room for it. Accordingly, the dummy ring 45 may be manufactured using a carbon-containing material such as graphite having a melting point higher than the firing temperature and lower than the casting temperature when the immersion nozzle 40 is manufactured.
  • the dummy ring 45 / liner 43 or the dummy ring 45 / liner 43 / dummy ring 45 is provided in the nozzle body 41 along the longitudinal direction of the nozzle body 41. Can be formed.
  • a dummy ring 45 exists on one side of the liner 43, for example, as shown in FIG. 4A, but during casting, the dummy ring 45 is shown in FIG. 4B.
  • the liner 43 is expanded by a volume 'x' by the heat of the molten steel so that the dummy ring 45 is dissolved It fills the space to form. Accordingly, the stress generated between the liner 43 and the nozzle body 41 due to the volume expansion of the liner 43 may be alleviated to prevent or prevent cracks or damage to the liner 43.
  • a slag line portion 47 may be formed on an outer wall of the immersion nozzle 40.
  • the slag line portion 47 is configured to increase the corrosion resistance to the slag (or flux 62), molten steel, etc., and may be formed around the hot water surface of the molten steel in the upper side of the discharge port 42, for example.
  • the slag line portion 47 may be formed using various materials, and for example, may be formed using a mixed material such as calcia / magnesia partially stabilized zirconia or graphite.
  • the power supply unit 70 energizes the molten steel in the tundish 10 and the immersion nozzle 40.
  • the first electrode 72 may be provided to apply power to the molten steel in the tundish, and the immersion nozzle 40 may be used as the second electrode.
  • the first electrode 72 may be provided to be immersed in the molten steel in the tundish, and the first electrode 72 may be the same as the immersion nozzle 40, that is, the nozzle body 41. It can be formed of a material.
  • the power supply unit 70 applies a power, for example, a voltage or a current to the first electrode 72 and the second electrode (immersion nozzle 40), the first electrode 72 is a cathode, the second The electrode is used as an anode to apply power.
  • a power for example, a voltage or a current
  • the first electrode 72 is a cathode
  • the second The electrode is used as an anode to apply power.
  • When power is applied to the first electrode 72 and the second electrode electrons move from the first electrode 72 to the second electrode side, and oxygen ions decomposed at the interface between the molten steel and the immersion nozzle 40 move the electrons.
  • the nozzle according to an embodiment of the present invention the process of preparing a raw material for forming the immersion nozzle 40, the process of forming a molded body by injecting and pressing the raw material to the forming mold for forming the immersion nozzle 40 and The method may include baking the molded body to form the immersion nozzle 40.
  • the process of preparing the raw material may include preparing a raw material for forming the nozzle body 41, a raw material for forming the liner 43, and a raw material for forming the dummy ring 45.
  • each raw material is inject
  • the cylindrical core material may be inserted into the mold, and the spacer for forming the liner and the dummy ring may be inserted to be spaced apart from the core material.
  • the raw material for forming the liner 43 and the dummy ring 45 is sequentially injected between the spacer and the core, and the raw material for forming the nozzle body 41 is injected between the spacer and the forming mold. Thereafter, the spacer is removed, and then a raw material injected into the mold is pressed to form a molded body for forming the immersion nozzle 40.
  • the molded body is taken out from the mold and the molded body is fired at a temperature of about 1000 ° C. or less in the firing furnace to manufacture the immersion nozzle 40.
  • the dummy ring 45 may maintain the shape formed when the molded body is formed.
  • the dummy ring 45 is dissolved and removed by the heat of molten steel to form a space corresponding to the volume expansion of the liner 43 above, above, and below the liner 43. It can be easily secured. Accordingly, when the volume of the liner 43 is expanded by molten steel at the time of casting, it is possible to prevent the liner 43 from being cracked or the liner 43 is broken by the space in which the dummy ring 45 is removed.
  • Casting method as a casting method for casting the cast steel 61 by injecting the molten steel 60 accommodated in the tundish 10 into the mold 50 through the immersion nozzle 40, 60) and the immersion nozzle 40 are energized to discharge oxygen contained in the molten steel to the immersion nozzle side.
  • a circuit for energizing the molten steel 60 and the immersion nozzle 40 may be configured before starting casting.
  • the first electrode 72 is immersed in the molten steel 60 in the tundish 10, and the first electrode 72 and the second electrode, that is, the nozzle body 41 are connected to each other by using wires.
  • the first electrode 72 and the second electrode are connected to the power supply unit 70 that is installed externally through the wiring.
  • the molten steel 60 in the tundish 10 is injected into the mold 50, and power is supplied to the nozzle body 41, which is the first electrode 72 and the second electrode, through the power supply unit 70. do.
  • the first electrode 72 is set to be a cathode
  • the second electrode is set to be an anode so that current flows from the first electrode 72 to the second electrode side.
  • the power applied to the first electrode 72 and the second electrode through the power supply unit 70 may be adjusted to apply a current density of about 0.1 to about 10 mA / cm 2. This is because the liner 43 provided inside the nozzle body 41 has very high ion conductivity, so that oxygen ions can smoothly move even if a relatively small current flows. At this time, when the current density is smaller than the suggested range, the ionization of the metal oxide and the movement of oxygen ions are not performed smoothly. In addition, since the ionization of the metal oxide and the movement of oxygen ions are performed smoothly within the range of the current density, the current density does not need to be larger than the range.
  • the liner 43 which is a solid electrolyte has permeability only to oxygen ions, cations are dissolved and absorbed in molten steel. This process is continuously performed while power is applied, and it is possible to suppress or prevent the generation and attachment of metal oxides to the inner wall of the immersion nozzle 40. Therefore, it is possible to prevent nozzle clogging that may occur due to the generation and attachment of metal oxides.
  • a liner was formed with a solid electrolyte on a portion of the inner wall of the immersion nozzle, and the immersion nozzle was prepared without the rest of the liner. Casting was performed in a 13 ton scale test facility using the immersion nozzle thus produced. At this time, power was supplied such that a current density of 2 mA / cm 2 was applied. In order to accelerate the nozzle clogging phenomenon, a condition in which a large amount of Al 2 O 3 inclusions in molten steel was generated was applied. Subsequently, the immersion nozzle used for the test was cut and the inside thereof was observed.
  • the nozzle, the casting apparatus and the casting method according to the present invention can improve the productivity of the cast by suppressing or preventing the nozzle clogging phenomenon in the continuous casting process for casting the cast.

Abstract

The present invention relates to a nozzle, a casting device, and a casting method, the casting device comprising: a turn dish in which molten steel is housed; an immersion nozzle connected to the lower portion of the turn dish and including a nozzle body, and a liner covering at least a portion of the inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO2, MSZ); and a power supply unit running an electric current between the molten steel housed in the turn dish and the nozzle body, wherein nozzle blockage can be suppressed through an electrochemical deoxidation reaction.

Description

노즐, 주조장치 및 주조방법Nozzle, Casting Machine and Casting Method
본 발명은 노즐, 주조장치 및 주조방법에 관한 것으로서, 보다 상세하게는 전기화학적 탈산 반응을 통해 막힘 현상을 억제할 수 있는 노즐, 주조장치, 주조방법에 관한 것이다.The present invention relates to a nozzle, a casting apparatus, and a casting method, and more particularly, to a nozzle, a casting apparatus, and a casting method capable of suppressing clogging through an electrochemical deoxidation reaction.
연속주조공정은 정련이 완료된 용강이 담겨 있는 래들(ladle)이 연속주조장치에 안착되어 액체 상태의 용강이 래들에서 턴디쉬(tundish)를 거쳐 몰드(mold)로 이동하면서 고체 상태의 주편으로 변하는 공정이다. 이때, 침지노즐은 턴디쉬 하부에 위치하여 턴디쉬에서 몰드로 용강을 이동시키고, 용강에 침지되어 용강과 오랜시간 접하게 되므로 우수한 내구성이 요구된다. 침지노즐은 주로 내화성 및 용융 금속에 대한 내식성이 우수한 알루미나(Al2O3)와 개재물(슬래그 성분)에 대하여 젖음성이 작고 팽창량이 적으며 열전도성이 양호한 흑연(C)을 조합한 Al2O3-C 재질로 형성된다. The continuous casting process is a process in which a ladle containing refined molten steel is placed in a continuous casting apparatus, and the liquid molten steel moves from a ladle to a mold through a tundish and turns into a solid cast. to be. At this time, the immersion nozzle is located in the lower tundish to move the molten steel from the tundish to the mold, immersed in the molten steel is in contact with the molten steel for a long time is required for excellent durability. Immersion nozzle is usually excellent in corrosion resistance of alumina to the refractory and the molten metal (Al 2 O 3) and inclusions were ever amount small wettability expansion with respect to (slag composition) Al 2 O 3 a combination of good thermal conductivity of graphite (C) It is made of -C material.
침지노즐은 턴디쉬의 용강을 몰드로 공급하는 유로의 역할을 하는 원통형 내화물이다. 용강이 침지노즐 내부로 이동하는 동안 온도의 하락, 용강과 노즐 내벽 계면에서의 계면반응, 용강 중 개재물의 노즐 내벽 부착 등의 이유로 노즐 내벽으로부터 노즐 중심 방향으로 막힘층이 성장한다. 이와 같은 노즐 막힘 현상은 연속주조 공정의 단락을 초래하여 생산성 및 주편 품질 저하 등의 악영향을 야기하게 된다. 따라서 이와 같은 노즐 막힘을 방지하기 위하여 비활성기체를 노즐 내부에서 용강으로 공급하여 기포에 의해 개재물의 부착을 방지하는 포러스(Porus)형 침지노즐, 노즐 막힘을 유발하는 대표 산화물인 산화 알루미늄과 반응하여 저융점 화합물을 형성하는 내화물을 도입하여 노즐 막힘층이 노즐 재질과 함께 녹아 내리게 하는 용손형 노즐 및 개재물의 부착이나 용강과의 접촉을 억제하는 내화물 재질을 도입하여 노즐 막힘을 저감하고자 하는 노력이 지속되고 있다. The immersion nozzle is a cylindrical refractory serving as a flow path for supplying molten steel of the tundish to the mold. As the molten steel moves into the immersion nozzle, a clogging layer grows from the nozzle inner wall toward the nozzle center due to a drop in temperature, an interfacial reaction at the interface between the molten steel and the nozzle inner wall, and adhesion of the nozzle inner wall of the inclusions in the molten steel. Such nozzle clogging may cause a short circuit in the continuous casting process, which may adversely affect productivity and cast quality. Therefore, in order to prevent the clogging of the nozzle, an inert gas is supplied to the molten steel from inside the nozzle to prevent the adhesion of inclusions by bubbles, and a porous type immersion nozzle is reacted with aluminum oxide, which is a representative oxide causing the nozzle clogging. Efforts are being made to reduce nozzle clogging by introducing refractory materials that prevent melting of the nozzle clogging layer with the nozzle material by introducing refractory forming the melting point compound and refractory material that suppresses attachment of inclusions or contact with molten steel. have.
본 발명은 주조 시 전기화학적 탈산 반응을 일으켜 노즐 막힘 현상을 억제할 수 있는 노즐, 주조장치 및 주조방법을 제공한다. The present invention provides a nozzle, a casting apparatus and a casting method that can suppress the clogging phenomenon by causing an electrochemical deoxidation reaction during casting.
본 발명은 주조 공정 효율 및 생산성을 향상시킬 수 있는 노즐, 주조장치 및 주조방법을 제공한다.The present invention provides a nozzle, casting apparatus and casting method that can improve the casting process efficiency and productivity.
본 발명의 실시 형태에 따른 노즐은, 용강이 이동할 수 있는 내공부를 갖고, 상기 용강이 상기 내공부의 외측으로 이동할 수 있는 토출구가 형성되는 노즐 몸체; 및 상기 노즐 몸체의 내벽의 적어도 일부를 둘러싸고, 마그네시아 안정화 지르코니아(MgO stabilized ZrO2, MSZ)를 포함하는 라이너;를 포함할 수 있다. The nozzle according to the embodiment of the present invention, the nozzle body has an internal hole to which the molten steel can move, the discharge hole through which the molten steel can move to the outside of the inner hole; And a liner surrounding at least a portion of the inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ).
상기 노즐 몸체는 Al2O3를 포함하고, 상기 노즐 몸체는 상기 노즐 몸체 전체 중량에 대하여 20중량% 내지 30중량%의 탄소 성분을 함유할 수 있다. The nozzle body may include Al 2 O 3 , and the nozzle body may contain 20 wt% to 30 wt% of a carbon component based on the total weight of the nozzle body.
상기 라이너는 마그네시아 안정화 지르코니아 80 내지 95중량%와, 탄소 5 내지 20 중량%를 포함할 수 있다. The liner may comprise 80 to 95% by weight of magnesia stabilized zirconia and 5 to 20% by weight of carbon.
상기 마그네시아 안정화 지르코니아는 마그네시아(MgO) 8 내지 15mol%를 함유할 수 있다. The magnesia stabilized zirconia may contain 8 to 15 mol% of magnesia (MgO).
상기 라이너의 길이방향에 대해서 상기 라이너의 상측과 하측 중 적어도 어느 한 쪽에 더미 링이 구비될 수 있다. A dummy ring may be provided on at least one of an upper side and a lower side of the liner with respect to the length direction of the liner.
상기 더미 링은 탄소 성분을 포함할 수 있다. The dummy ring may include a carbon component.
상기 더미 링은 상기 라이너의 길이에 대하여 1~2%의 길이로 형성될 수 있다. The dummy ring may be formed to have a length of 1 to 2% with respect to the length of the liner.
본 발명의 실시 형태에 따른 주조장치는, 주조 장치로서, 내부에 용강이 수용되는 턴디쉬와; 상기 턴디쉬 하부에 연결되고, 노즐 몸체와, 상기 노즐 몸체의 내벽의 적어도 일부를 둘러싸고 마그네시아 안정화 지르코니아(MgO stabilized ZrO2, MSZ)를 포함하는 라이너를 포함하는 침지 노즐; 및 상기 턴디쉬에 수용된 용강과 상기 노즐 몸체를 통전시키는 전원부를; 포함할 수 있다.A casting apparatus according to an embodiment of the present invention, a casting device, and a tundish is accommodated therein molten steel; An immersion nozzle connected to the tundish and including a nozzle body and a liner including at least a portion of an inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ); And a power supply unit configured to energize the molten steel accommodated in the tundish and the nozzle body. It may include.
상기 노즐 몸체는 Al2O3를 포함하고, 상기 노즐 몸체는 상기 노즐 몸체 전체 중량에 대하여 20중량% 내지 30중량% 의 탄소 성분을 함유할 수 있다.The nozzle body may include Al 2 O 3 , and the nozzle body may contain 20 wt% to 30 wt% of a carbon component based on the total weight of the nozzle body.
상기 라이너는 마그네시아 안정화 지르코니아 80 내지 95중량%와, 탄소 5 내지 20 중량%를 포함할 수 있다.The liner may comprise 80 to 95% by weight of magnesia stabilized zirconia and 5 to 20% by weight of carbon.
상기 마그네시아 안정화 지르코니아는 마그네시아(MgO) 8 내지 15mol%를 함유할 수 있다. The magnesia stabilized zirconia may contain 8 to 15 mol% of magnesia (MgO).
상기 라이너의 길이방향에 대해서 상기 라이너의 상측과 하측 중 적어도 어느 한 쪽에 더미 링이 구비될 수 있다. A dummy ring may be provided on at least one of an upper side and a lower side of the liner with respect to the length direction of the liner.
상기 더미 링은 탄소 성분을 포함할 수 있다. The dummy ring may include a carbon component.
상기 더미 링은 상기 라이너의 길이에 대하여 1~2%의 길이로 형성될 수 있다. The dummy ring may be formed to have a length of 1 to 2% with respect to the length of the liner.
상기 턴디쉬 내 용강에 침지되는 전극을 포함하고, 상기 전원부는 상기 전극 및 상기 침지 노즐에 전원을 인가할 수 있다.The electrode may be immersed in the molten steel in the tundish, and the power supply unit may apply power to the electrode and the immersion nozzle.
본 발명의 실시 형태에 따른 주조방법은, 턴디쉬에 수용된 용강을 침지 노즐을 통해 몰드로 주입하여 주편을 주조하는 주조방법으로서, 상기 침지 노즐은 상기 턴디쉬에 연결되는 노즐 몸체와, 상기 노즐 몸체 내벽에 구비되고 마그네시아 안정화 지르코니아를 함유하는 라이너를 포함하고, 상기 용강과 상기 노즐 몸체를 통전시켜 상기 용강 중 함유되는 산소를 상기 침지 노즐 측으로 배출시킬 수 있다. A casting method according to an embodiment of the present invention is a casting method of casting a cast steel by injecting molten steel contained in a tundish into a mold through an immersion nozzle, wherein the immersion nozzle comprises a nozzle body connected to the tundish, and the nozzle body. A liner is provided on the inner wall and contains magnesia stabilized zirconia, and the molten steel and the nozzle body are energized to discharge oxygen contained in the molten steel to the immersion nozzle side.
상기 용강과 상기 노즐 몸체가 통전되면, 상기 용강 중 생성된 금속산화물이 산소이온과 양이온으로 분해되고, 상기 산소이온이 상기 라이너를 통해 상기 노즐 몸체로 이동하여 상기 용강 중 산소가 침지 노즐 측으로 배출될 수 있다. When the molten steel and the nozzle body are energized, the metal oxide generated in the molten steel is decomposed into oxygen ions and cations, and the oxygen ions are moved to the nozzle body through the liner so that oxygen in the molten steel is discharged to the immersion nozzle side. Can be.
상기 용강은 음극으로, 상기 침지 노즐은 양극으로 하여 통전시킬 수 있다. The molten steel may be supplied with a cathode and the immersion nozzle as an anode.
상기 용강과 상기 침지 노즐을 통전시키는 과정에서 0.1 내지 10mA/㎠의 전류 밀도가 인가되도록 통전시킬 수 있다. In the process of energizing the molten steel and the immersion nozzle may be energized so that a current density of 0.1 to 10mA / ㎠.
상기 라이너의 상측 및 하측의 적어도 한 쪽에는 더미링이 구비되고, 상기 더미링은 상기 주편을 주조하는 과정에서 용해되어 공간을 형성할 수 있다.At least one of upper and lower sides of the liner is provided with a dummy ring, and the dummy ring may be dissolved in the process of casting the cast to form a space.
본 발명에 따른 노즐, 주조장치 및 주조방법은, 노즐, 예컨대 주조공정에서 사용되는 침지 노즐의 내공부가 막히는 현상을 억제 혹은 방지할 수 있다. 즉, 주조 온도에서 용강과 접촉하는 노즐 내공부에 전기화학적 탈산을 가능하게 하는 고체전해질을 이용하여 라이너를 형성하고 용강과 침지 노즐을 통전시킴으로써 주조 중 용강과 접촉하는 침지 노즐의 내벽에 금속산화물 등의 개재물이 적층되어 노즐 막힘 현상이 발생하는 것을 억제 혹은 방지할 수 있다. 이를 통해 노즐 내벽에서의 계면 산소 농도를 낮춰 노즐 내벽과 용강의 젖음성을 저감시킬 수 있다. 따라서 노즐 막힘을 일으키는 주요 요인인 노즐 내공부에서 개재물 생성과 용강의 젖음성이 개선되어 노즐이 막히는 현상을 억제 혹은 방지할 수 있다. 이에 노즐 막힘에 의한 주조 중단 등의 문제점을 해결할 수 있으므로 주조 효율 및 생산성을 향상시킬 수 있고, 이를 이용하여 제조되는 주편의 품질을 향상시킬 수 있다. 또한, 노즐의 수명을 향상시켜 노즐 교체에 소요되는 시간과 비용을 절감할 수 있다. The nozzle, the casting apparatus, and the casting method according to the present invention can suppress or prevent a phenomenon in which the internal air portion of the nozzle, for example, the immersion nozzle used in the casting step, is blocked. That is, a metal oxide or the like is formed on the inner wall of the immersion nozzle in contact with the molten steel during casting by forming a liner by using a solid electrolyte that enables electrochemical deoxidation to the nozzle internal hole in contact with the molten steel at the casting temperature and energizing the immersion nozzle with molten steel. It is possible to suppress or prevent the occurrence of clogging due to stacking of inclusions. Through this, the concentration of interfacial oxygen in the nozzle inner wall can be reduced to reduce the wettability between the nozzle inner wall and the molten steel. Therefore, the inclusions and the wettability of the molten steel are improved in the nozzle inner cavity, which is the main factor causing the nozzle clogging, thereby preventing or preventing the nozzle from clogging. This can solve the problems, such as interruption of the casting due to clogging the nozzle can improve the casting efficiency and productivity, it is possible to improve the quality of the cast produced using this. In addition, it is possible to reduce the time and cost of nozzle replacement by improving the life of the nozzle.
또한, 침지 노즐 내부에 이온전도성이 우수한 고체전해질을 이용하여 라이너를 형성하기 때문에 개재물 생성 억제를 위한 전력 소모를 감소시킬 수 있다. In addition, since the liner is formed using a solid electrolyte having excellent ion conductivity in the immersion nozzle, power consumption for suppressing inclusion generation may be reduced.
도 1은 본 발명의 실시 예에 따른 주조장치의 개략도.1 is a schematic view of a casting apparatus according to an embodiment of the present invention.
도 2는 본 발명의 실시 예에 따른 주조장치에 적용되는 노즐의 단면도.2 is a cross-sectional view of a nozzle applied to the casting apparatus according to the embodiment of the present invention.
도 3은 주조 중 노즐의 내공부에서 발생하는 탈산 반응 모식도.Figure 3 is a schematic diagram of the deoxidation reaction occurring in the inner cavity of the nozzle during casting.
도 4는 주조 중 노즐 내부 구조의 변화를 보여주는 단면도. 4 is a cross-sectional view showing a change in the nozzle internal structure during casting.
이하에서는 첨부된 도면을 참조하여 본 발명의 실시예를 더욱 상세히 설명하기로 한다. 그러나 본 발명은 이하에서 개시되는 실시예에 한정되는 것이 아니라 서로 다른 다양한 형태로 구현될 것이며, 단지 본 실시예들은 본 발명의 개시가 완전하도록 하며, 통상의 지식을 가진 자에게 발명의 범주를 완전하게 알려주기 위해 제공되는 것이다. 설명 중, 동일 구성에 대해서는 동일한 참조부호를 부여하도록 하고, 도면은 본 발명의 실시예를 정확히 설명하기 위하여 크기가 부분적으로 과장될 수 있으며, 도면상에서 동일 부호는 동일한 요소를 지칭한다.Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention in more detail. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in various forms, and only the embodiments are intended to complete the disclosure of the present invention, and to those skilled in the art to fully understand the scope of the invention. It is provided to inform you. In the description, like reference numerals refer to like elements, and the drawings may be partially exaggerated in size in order to accurately describe embodiments of the present invention, and like reference numerals refer to like elements in the drawings.
도 1은 본 발명의 실시 예에 따른 주조장치의 개략도이고, 도 2는 본 발명의 실시 예에 따른 주조장치에 적용되는 노즐의 단면도이고, 도 3은 주조 중 노즐의 내공부에서 발생하는 탈산 반응 모식도이고, 도 4는 주조 중 노즐 내부 구조의 변화를 보여주는 단면도이다. 1 is a schematic view of a casting apparatus according to an embodiment of the present invention, Figure 2 is a cross-sectional view of a nozzle applied to the casting apparatus according to an embodiment of the present invention, Figure 3 is a deoxidation reaction occurring in the inner hole of the nozzle during casting It is a schematic diagram, and FIG. 4 is sectional drawing which shows the change of the nozzle internal structure during casting.
도 1을 참조하면, 주조장치, 예컨대 연속주조장치는 정련을 거친 용강을 담는 용기인 래들(ladle)로부터 용강(60)을 저장하고 분배하는 역할을 하는 턴디쉬(10), 용강(60)의 유량을 제어하는 스토퍼(20) 및 슬라이딩 플레이트(30), 용강(60)을 몰드(50)로 배출하는 침지 노즐(40) 및 용강(60)을 응고시켜 주편(61)으로 만드는 몰드(50)를 포함할 수 있다. 도 1에서는 용강의 유량을 제어하기 위해 스토퍼(20)와 슬라이딩 플레이트(30)이 동시에 구비되는 것으로 도시하고 있으나, 실제 조업에서는 스토퍼(20)와 슬라이딩 플레이트(30) 중 어느 한 가지가 이용될 수 있다. 또한, 주조장치는 턴디쉬(10) 내 용강과 침지 노즐(40)에 전압을 인가하는 전원부(70)를 포함할 수 있다. Referring to FIG. 1, a casting apparatus, such as a continuous casting apparatus, includes a tundish 10 and a molten steel 60 that serve to store and distribute the molten steel 60 from a ladle, which is a vessel containing refined molten steel. Mold 50 for solidifying the stopper 20 and the sliding plate 30 for controlling the flow rate, the immersion nozzle 40 for discharging the molten steel 60 into the mold 50 and the molten steel 60 to form a cast steel 61. It may include. In FIG. 1, the stopper 20 and the sliding plate 30 are simultaneously provided to control the flow rate of the molten steel. However, any one of the stopper 20 and the sliding plate 30 may be used in actual operation. have. In addition, the casting apparatus may include a power supply unit 70 for applying a voltage to the molten steel in the tundish 10 and the immersion nozzle 40.
도 2를 참조하면, 침지 노즐(40)은 용강이 이동할 수 있는 내공부를 갖고, 용강이 외측, 예컨대 몰드로 이동할 수 있는 토출구(42)를 포함하는 노즐 몸체(41)와, 노즐 몸체(41)의 내벽 적어도 일부를 둘러싸도록 구비되고 마그네시아 안정화 지르코니아(MgO stabilized ZrO2, MSZ)를 함유하는 라이너(43)를 포함할 수 있다. 또한, 도시되어 있지는 않지만, 침지 노즐(40)은 노즐 몸체(41)의 외벽의 적어도 일부를 감싸는 슬래그 라인부(47)를 포함할 수도 있다. 2, the immersion nozzle 40 has an internal hole through which molten steel can move, a nozzle body 41 including a discharge port 42 through which molten steel can move outward, for example, into a mold, and a nozzle body 41. ), the inner wall may be provided and includes a liner 43 which contains a magnesia-stabilized zirconia (MgO stabilized ZrO 2, MSZ) so as to surround at least a portion of. In addition, although not shown, the immersion nozzle 40 may include a slag line portion 47 surrounding at least a portion of the outer wall of the nozzle body 41.
노즐 몸체(41)는 용강이 이동할 수 있는 내공부를 갖도록 적어도 상부가 개방된 원통형의 형상으로 형성될 수 있다. 또한, 노즐 몸체(41)의 하부측에는 용강이 내공부에서 외측으로 토출될 수 있는 토출구(42)가 형성될 수 있다. 노즐 몸체(41)는 Al2O3-C를 이용하여 형성될 수 있다. 이때, 노즐 몸체(41)는 도전성을 가질 수 있도록 C 성분을 20 내지 30중량% 정도 포함하도록 형성될 수 있다. 이는 침지 노즐(40)과, 침지 노즐(40)을 따라 흐르는 용강 사이에 통전 회로를 형성하기 위함이다.The nozzle body 41 may be formed in a cylindrical shape having at least an upper portion open so as to have an inner cavity through which molten steel can move. In addition, a discharge port 42 through which molten steel may be discharged from the inner cavity to the outside may be formed at the lower side of the nozzle body 41. The nozzle body 41 may be formed using Al 2 O 3 -C. At this time, the nozzle body 41 may be formed to include about 20 to 30% by weight of the C component to have conductivity. This is for forming an energization circuit between the immersion nozzle 40 and the molten steel flowing along the immersion nozzle 40.
라이너(43)는 노즐 몸체(41)의 내벽, 즉 용강과 접촉하는 면에 형성될 수 있다. 라이너(43)는 노즐 몸체(41)의 내벽 전체에 걸쳐 형성될 수도 있으나 노즐 몸체(41)의 상부 측에서 토출구(42) 상부까지 형성될 수 있다. 이에 라이너(43)는 노즐 몸체(41) 내부에 노즐 몸체(41)의 내벽을 따라 상하방향이 개구된 중공의 원통형으로 형성될 수 있다. The liner 43 may be formed on the inner wall of the nozzle body 41, that is, the surface in contact with the molten steel. The liner 43 may be formed over the entire inner wall of the nozzle body 41, but may be formed from the upper side of the nozzle body 41 to the upper portion of the discharge port 42. Accordingly, the liner 43 may be formed in a hollow cylindrical shape in which the vertical direction is opened along the inner wall of the nozzle body 41 in the nozzle body 41.
라이너(43)는 노즐 몸체(41)의 내벽에 형성되어 용강 중 산소 이온을 노즐 몸체(41) 측으로 이동시키는 역할을 한다. 라이너(43)는 이온전도성이 우수한 물질로 잘 알려진 마그네시아 안정화 지르코니아(MSZ)로 형성될 수 있다. 마그네시아 안정화 지르코니아는 고체상태에서 이온이 전기를 안내하는 성질을 가지는 고체전해질로서, 고체연료전지, 용융 금속 중 산소의 농도를 측정하는 프로브(probe) 등 적용되고 있다. The liner 43 is formed on the inner wall of the nozzle body 41 to move oxygen ions in the molten steel toward the nozzle body 41. The liner 43 may be formed of magnesia stabilized zirconia (MSZ), which is well known as a material having excellent ion conductivity. Magnesia stabilized zirconia is a solid electrolyte having a property of ions guiding electricity in a solid state, and has been applied to a solid fuel cell, a probe for measuring the concentration of oxygen in molten metal, and the like.
본 발명에서는 이와 같은 마그네시아 안정화 지르코니아(MSZ)를 라이너(43)로 사용하여 용강 중 산소 이온을 노즐 몸체(41) 측으로 유도함으로써 침지 노즐(40) 내벽에 개재물, 예컨대 SiO2, Al2O3, TiO2 등의 금속산화물이 발생하는 것을 억제 혹은 방지할 수 있다. In the present invention, such magnesia stabilized zirconia (MSZ) is used as the liner 43 to guide oxygen ions in the molten steel toward the nozzle body 41, so that inclusions such as SiO 2 , Al 2 O 3 , TiO 2 Generation of metal oxides such as these can be suppressed or prevented.
주조 시 용강 중 함유되는 산소는 계면에서 활성화되는 특성으로 인해 용강과 침지 노즐(40) 내벽의 계면에서 금속산화물을 생성한다. 이렇게 생성된 금속산화물은 용강과의 계면 에너지가 높아서 용강 안에서 침지 노즐(40) 내벽으로 자발적으로 이동하여 부착된다. 이러한 과정이 반복 및 지속되면서 침지 노즐(40)의 내공부가 막히는 노즐 막힘 현상이 발생하게 된다. 이에 본 발명에서는 노즐 몸체(41) 내벽에 이온전도성이 우수한 고체전해질을 이용하여 라이너(43)를 형성하고, 용강과 침지 노즐(40), 즉 노즐 몸체(41)를 통전시켜 산소 이온을 용강 외부로 유도함으로써 침지 노즐(40) 내벽에 금속산화물의 부착을 억제 혹은 방지할 수 있다. Oxygen contained in the molten steel during casting generates metal oxide at the interface between the molten steel and the inner wall of the immersion nozzle 40 due to the property of being activated at the interface. The metal oxide thus produced has a high interfacial energy with molten steel and spontaneously moves to and adheres to the inner wall of the immersion nozzle 40 in the molten steel. As this process is repeated and continued, a nozzle clogging phenomenon occurs in which the inner cavity of the immersion nozzle 40 is blocked. Accordingly, in the present invention, the liner 43 is formed on the inner wall of the nozzle body 41 by using a solid electrolyte having excellent ion conductivity, and the molten steel and the immersion nozzle 40, that is, the nozzle body 41 are energized to carry oxygen ions out of the molten steel. It is possible to suppress or prevent the adhesion of the metal oxide to the inner wall of the immersion nozzle 40 by guiding to.
금속산화물의 생성 및 부착을 억제하는 메카니즘을 설명하면 다음과 같다. The mechanism for suppressing the formation and adhesion of metal oxides is as follows.
도 3의 (a)를 참조하면, 주조 시 용강 중 함유되는 산소는 금속 산화물을 형성하며 노즐 몸체(41) 내벽으로 이동하게 된다. 그리고 도 3의 (b)에 도시된 바와 같이, 용강과 노즐 몸체(41)가 통전되면, 금속산화물 주변으로 밀집한 전자가 금속산화물을 산소이온과 양이온(금속이온)으로 분해시킨다. 이렇게 분해된 산소이온은 도 3의 (c)에 도시된 바와 같이 이온전도성이 우수한 라이너(43)를 통해 노즐 몸체 쪽으로 이동하게 되고, 노즐 몸체의 기공을 통해 빠져나와 산소 가스를 생성하며 외부로 배출된다. 그리고 양이온은 용강 중으로 흡수된다. 이러한 과정, 즉 탈산반응을 통해 용강 중 산소를 용강 외부로 배출시킴으로써 침지 노즐(40) 내 금속산화물의 생성 및 부착을 억제함으로써 노즐 막힘 현상을 억제 혹은 방지할 수 있다. Referring to FIG. 3A, oxygen contained in molten steel during casting forms a metal oxide and moves to the inner wall of the nozzle body 41. As shown in FIG. 3B, when the molten steel and the nozzle body 41 are energized, electrons concentrated around the metal oxide decompose the metal oxide into oxygen ions and cations (metal ions). The decomposed oxygen ions are moved toward the nozzle body through the liner 43 having excellent ion conductivity, as shown in FIG. 3 (c), and escapes through the pores of the nozzle body to generate oxygen gas and discharge to the outside. do. And cations are absorbed into the molten steel. This process, that is, by deoxidizing the oxygen in the molten steel to the outside of the molten steel by suppressing the generation and adhesion of the metal oxide in the immersion nozzle 40 it is possible to suppress or prevent the nozzle clogging phenomenon.
라이너(43)는 라이너(43) 전체 중량에 대하여 마그네시아 안정화 지르코니아(MSZ) 80 내지 95중량%와, 탄소 5 내지 20중량%를 포함할 수 있다. 이때, 마그네시아 안정화 지르코니아(MSZ)는 온도 변화에 따른 상변이에 의해 체적변화가 일어나는 것을 억제하기 위하여 8 내지 15mol% 정도의 마그네시아(MgO)와, 나머지는 지르코니아(ZrO2)로 구성될 수 있다. 이와 같이 지르코니아에 마그네시아를 안정화제로 사용함으로써 지르코니아가 온도 변화에도 비교적 안정적인 상을 유지할 수 있으므로 주조 중 라이너(43)에 크랙이 발생하거나 파손되는 것을 방지할 수 있다. The liner 43 may include 80 to 95 wt% of magnesia stabilized zirconia (MSZ) and 5 to 20 wt% of carbon based on the total weight of the liner 43. At this time, magnesia stabilized zirconia (MSZ) may be composed of magnesia (MgO) of about 8 to 15 mol%, and the rest of the zirconia (ZrO 2 ) in order to suppress the volume change caused by the phase change according to the temperature change. By using magnesia as a stabilizer in this way, zirconia can maintain a relatively stable phase even with temperature changes, thereby preventing cracks or breakage in the liner 43 during casting.
한편, 라이너(43)를 온도 변화에 안정적인 마그네시아 안정화 지르코니아를 이용하여 제조하더라도 온도 변화에 따른 체적 팽창을 완전히 억제할 수는 없다. 또한, 라이너(43)와 노즐 몸체(41)의 열팽창률이 서로 다르며, 라이너(43)의 열팽창률이 노즐 몸체(41)의 열팽창률보다 크기 때문에 주조 시 라이너(43)의 체적 팽창에 의해 라이너(43)와 노즐 몸체(41) 간에 응력이 작용하여 라이너(43)에 크랙이 발생하거나 파손되는 현상이 발생할 수 있다. On the other hand, even if the liner 43 is manufactured using magnesia stabilized zirconia stable to temperature changes, volume expansion due to temperature changes cannot be completely suppressed. In addition, the thermal expansion coefficients of the liner 43 and the nozzle body 41 are different from each other, and the thermal expansion coefficient of the liner 43 is larger than that of the nozzle body 41, so that the liner 43 is formed by volume expansion of the liner 43 during casting. Stress may act between the 43 and the nozzle body 41 to cause a crack or breakage in the liner 43.
이에 라이너(43)의 길이 방향에 대해서 상측과 하측 중 적어도 어느 한 쪽에는 라이너(43)의 체적 팽창에 따른 공간을 확보하기 위하여 더미링(45)을 형성할 수 있다. 더미링(45)은 라이너(43)의 길이에 대해서 약 1 내지 2% 정도의 길이를 갖도록 형성될 수 있다. 더미링(45)의 길이가 제시된 범위보다 작은 경우에는 라이너(43)의 체적 팽창에 대해서 적절하게 대응할 수 없어 라이너(43)의 파손이 불가피하고, 더미링(45)의 길이가 제시된 범위보다 큰 경우에는 노즐 몸체(41)가 용강에 노출되어 금속 산화물이 생성 및 부착될 수 있다. 더미링(45)은 라이너(43)의 체적 팽창에 따른 공간을 확보할 수 있다면 형성할 필요는 없지만, 침지 노즐(40) 제조 특성 상 라이너(43)의 체적 팽창에 대응하는 공간을 확보하기 어렵기 때문에 불가피하게 형성되는 것이다. 즉, 침지 노즐(40)을 제조하는 과정은 침지 노즐(40)을 구성하는 원료를 성형틀에 주입한 후 가압 성형공정과 소성 공정을 포함하는데, 성형틀에 원료 주입 시 특정 위치, 다시 말해서 라이너(43)의 체적 팽창에 대응하는 공간을 확보하기 어렵기 때문이다. 이에 더미링(45)은 라이너(43)를 구성하는 성분보다 용융점이 낮은 물질을 이용하여 형성될 수 있다. 즉, 더미링(45)은 침지 노즐(40) 제조 시 라이너(43)의 상측 및 하측 중 어느 한 쪽에 형성되어 있지만, 주조 시에는 용강의 열에 의해 용해되어 제거됨으로써 라이너(43)의 체적 팽창을 위한 공간을 확보해줄 수 있다. 이에 더미링(45)은 침지 노즐(40) 제조 시 소성 온도보다 높고 주조 온도보다 낮은 용융점을 갖는 흑연 등과 같은 탄소 함유 물질을 이용하여 제조할 수 있다. Accordingly, the dummy ring 45 may be formed on at least one of the upper side and the lower side with respect to the longitudinal direction of the liner 43 in order to secure a space due to the volume expansion of the liner 43. The dummy ring 45 may be formed to have a length of about 1 to 2% of the length of the liner 43. If the length of the dummy ring 45 is smaller than the indicated range, it is impossible to adequately cope with the volume expansion of the liner 43 so that breakage of the liner 43 is inevitable, and the length of the dummy ring 45 is larger than the indicated range. In this case, the nozzle body 41 may be exposed to molten steel to generate and attach a metal oxide. The dummy ring 45 does not need to be formed if the space according to the volume expansion of the liner 43 can be secured, but it is difficult to secure the space corresponding to the volume expansion of the liner 43 due to the manufacturing characteristics of the immersion nozzle 40. Because it is inevitably formed. That is, the process of manufacturing the immersion nozzle 40 includes a pressure molding process and a firing process after injecting the raw material constituting the immersion nozzle 40 into the molding die, and when the raw material is injected into the molding die, that is, a liner This is because it is difficult to secure a space corresponding to the volume expansion of (43). Accordingly, the dummy ring 45 may be formed using a material having a lower melting point than the components constituting the liner 43. That is, the dummy ring 45 is formed on either of the upper side and the lower side of the liner 43 at the time of manufacturing the immersion nozzle 40, but during casting, the dummy ring 45 is dissolved and removed by the heat of molten steel to thereby increase the volume expansion of the liner 43. You can make room for it. Accordingly, the dummy ring 45 may be manufactured using a carbon-containing material such as graphite having a melting point higher than the firing temperature and lower than the casting temperature when the immersion nozzle 40 is manufactured.
이와 같은 구성을 통해 노즐 몸체(41) 내부에는 노즐 몸체(41)의 길이방향을 따라 더미링(45)/라이너(43) 또는 더미링(45)/라이너(43)/더미링(45)이 형성될 수 있다. 주조 전에는 도 4의 (a)에 도시된 바와 같이 라이너(43)의 일측, 예컨대 상측에 더미링(45)이 존재하지만, 주조 시에는 도 4의 (b)에 도시된 바와 같이 더미링(45)이 용강의 열에 의해 제거되어 라이너(43) 상측, 또는 상측 및 하측에 공간을 형성하게 되고, 용강의 열에 의해 라이너(43)는 'x' 만큼 체적이 팽창하여 더미링(45)이 용해되면서 형성하는 공간을 메우게 된다. 이에 라이너(43)의 체적 팽창에 의한 라이너(43)와 노즐 몸체(41) 간에 발생하는 응력을 완화시켜 라이너(43)에 크랙이 발생하거나 파손되는 것을 억제 혹은 방지할 수 있다. Through such a configuration, the dummy ring 45 / liner 43 or the dummy ring 45 / liner 43 / dummy ring 45 is provided in the nozzle body 41 along the longitudinal direction of the nozzle body 41. Can be formed. Before casting, a dummy ring 45 exists on one side of the liner 43, for example, as shown in FIG. 4A, but during casting, the dummy ring 45 is shown in FIG. 4B. ) Is removed by the heat of the molten steel to form a space above or below the liner 43, the liner 43 is expanded by a volume 'x' by the heat of the molten steel so that the dummy ring 45 is dissolved It fills the space to form. Accordingly, the stress generated between the liner 43 and the nozzle body 41 due to the volume expansion of the liner 43 may be alleviated to prevent or prevent cracks or damage to the liner 43.
또한, 침지 노즐(40)의 외벽에는 슬래그 라인부(47)가 형성될 수 있다. 슬래그 라인부(47)는 슬래그(또는 플럭스, 62), 용강 등에 대한 내식성을 높이는 구성으로서, 토출구(42) 상부측 예컨대 몰드 내 용강의 탕면 주변에 형성될 수 있다. 슬래그 라인부(47)는 다양한 물질을 이용하여 형성될 수 있으며, 예컨대 칼시아·마그네시아 부분 안정화 지르코니아, 흑연 등의 혼합 물질을 이용하여 형성될 수 있다. In addition, a slag line portion 47 may be formed on an outer wall of the immersion nozzle 40. The slag line portion 47 is configured to increase the corrosion resistance to the slag (or flux 62), molten steel, etc., and may be formed around the hot water surface of the molten steel in the upper side of the discharge port 42, for example. The slag line portion 47 may be formed using various materials, and for example, may be formed using a mixed material such as calcia / magnesia partially stabilized zirconia or graphite.
전원부(70)는 턴디쉬(10) 내 용강과 침지 노즐(40)을 통전시킨다. 이에 턴디쉬 내 용강에 전원을 인가하기 위한 제1전극(72)이 구비될 수 있고, 제2전극으로 침지 노즐(40)이 사용될 수 있다. 턴디쉬 내 용강에 전원을 인가하기 위해서 제1전극(72)은 턴디쉬 내 용강에 침지되도록 구비될 수 있으며, 제1전극(72)은 침지 노즐(40), 즉 노즐 몸체(41)와 동일한 물질로 형성될 수 있다. 또한, 전원부(70)는 제1전극(72)과 제2전극(침지 노즐(40))에 전원, 예컨대 전압 또는 전류를 인가하며, 제1전극(72)은 음극(cathode)으로, 제2전극은 양극(anode)으로 하여 전원을 인가한다. 이에 제1전극(72)과 제2전극에 전원을 인가하면 전자가 제1전극(72)에서 제2전극 측으로 이동하게 되고, 용강과 침지 노즐(40) 계면에서 분해된 산소 이온이 전자의 이동방향, 즉 용강에서 노즐 몸체 측으로 이동하게 된다. 따라서 용강 중 산소 이온이 라이너(43)를 통해 노즐 몸체(41) 측으로 이동하여 외부로 배출될 수 있으며, 이러한 과정을 통해 침지 노즐(40)의 내공부에 금속산화물이 부착되어 노즐 막힘 현상이 발생하는 것을 억제 혹은 방지할 수 있다. The power supply unit 70 energizes the molten steel in the tundish 10 and the immersion nozzle 40. The first electrode 72 may be provided to apply power to the molten steel in the tundish, and the immersion nozzle 40 may be used as the second electrode. In order to apply power to the molten steel in the tundish, the first electrode 72 may be provided to be immersed in the molten steel in the tundish, and the first electrode 72 may be the same as the immersion nozzle 40, that is, the nozzle body 41. It can be formed of a material. In addition, the power supply unit 70 applies a power, for example, a voltage or a current to the first electrode 72 and the second electrode (immersion nozzle 40), the first electrode 72 is a cathode, the second The electrode is used as an anode to apply power. When power is applied to the first electrode 72 and the second electrode, electrons move from the first electrode 72 to the second electrode side, and oxygen ions decomposed at the interface between the molten steel and the immersion nozzle 40 move the electrons. Direction, ie from the molten steel to the nozzle body. Therefore, the oxygen ions in the molten steel may be discharged to the outside by moving to the nozzle body 41 through the liner 43. Through this process, a metal oxide is attached to the inner cavity of the immersion nozzle 40 to cause nozzle clogging. Can be suppressed or prevented.
이하에서는 본 발명의 실시 예에 따른 노즐을 제조 방법에 대해서 설명한다. Hereinafter, a method of manufacturing a nozzle according to an embodiment of the present invention.
본 발명의 실시 예에 따른 노즐은, 침지 노즐(40)을 형성하기 위한 원료를 마련하는 과정과, 침지 노즐(40)을 형성하기 위한 성형틀에 원료를 주입하고 가압하여 성형체를 형성하는 과정과, 성형체를 소성하여 침지 노즐(40)을 형성하는 과정을 포함할 수 있다. The nozzle according to an embodiment of the present invention, the process of preparing a raw material for forming the immersion nozzle 40, the process of forming a molded body by injecting and pressing the raw material to the forming mold for forming the immersion nozzle 40 and The method may include baking the molded body to form the immersion nozzle 40.
원료를 마련하는 과정은 노즐 몸체(41)를 형성하기 위한 원료와, 라이너(43)를 형성하기 위한 원료 및 더미링(45)을 형성하기 위한 원료를 마련하는 과정을 포함할 수 있다. The process of preparing the raw material may include preparing a raw material for forming the nozzle body 41, a raw material for forming the liner 43, and a raw material for forming the dummy ring 45.
원료가 마련되면, 성형틀에 각각의 원료를 주입하여 침지 노즐(40) 성형체를 형성한다. 이때, 성형틀 내부에 원통형의 심재를 삽입하고, 라이너 및 더미링을 형성하기 위한 스페이서를 심재 외측에 이격되도록 삽입할 수 있다. 그리고 스페이서와 심재 사이에는 라이너(43)와 더미링(45)을 형성하기 위한 원료를 순차적으로 주입하고, 스페이서와 성형틀 사이에는 노즐 몸체(41)를 형성하기 위한 원료를 주입한다. 이후 스페이서를 제거한 다음 성형틀 내부에 주입된 원료를 가압하여 침지 노즐(40)을 형성하기 위한 성형체를 형성한다. When a raw material is provided, each raw material is inject | poured into a shaping | molding die, and the immersion nozzle 40 molded object is formed. At this time, the cylindrical core material may be inserted into the mold, and the spacer for forming the liner and the dummy ring may be inserted to be spaced apart from the core material. The raw material for forming the liner 43 and the dummy ring 45 is sequentially injected between the spacer and the core, and the raw material for forming the nozzle body 41 is injected between the spacer and the forming mold. Thereafter, the spacer is removed, and then a raw material injected into the mold is pressed to form a molded body for forming the immersion nozzle 40.
이후, 성형틀로부터 성형체를 인출하고 소성로에서 성형체를 약 1000℃ 이하의 온도에서 소성하여 침지 노즐(40)을 제조한다. 성형체를 소성하는 과정에서 더미링(45)은 성형체 형성 시 형성된 모양을 그대로 유지할 수 있다. Thereafter, the molded body is taken out from the mold and the molded body is fired at a temperature of about 1000 ° C. or less in the firing furnace to manufacture the immersion nozzle 40. In the process of firing the molded body, the dummy ring 45 may maintain the shape formed when the molded body is formed.
이렇게 형성된 침지 노즐(40)을 이용하여 주조를 실시하면 더미링(45)은 용강의 열에 의해 용해되어 제거됨으로써 라이너(43) 상측이나 상측 및 하측에 라이너(43)의 체적 팽창에 대응하는 공간을 용이하게 확보할 수 있다. 이에 따라 주조 시 용강에 의해 라이너(43)의 체적이 팽창하는 경우 더미링(45)이 제거된 공간에 의해 라이너(43)에 균열이 발생하거나 라이너(43)가 파손되는 것을 방지할 수 있다. When casting is performed using the immersion nozzle 40 formed as described above, the dummy ring 45 is dissolved and removed by the heat of molten steel to form a space corresponding to the volume expansion of the liner 43 above, above, and below the liner 43. It can be easily secured. Accordingly, when the volume of the liner 43 is expanded by molten steel at the time of casting, it is possible to prevent the liner 43 from being cracked or the liner 43 is broken by the space in which the dummy ring 45 is removed.
이하에서는 본 발명의 실시 예에 따른 주조장치를 이용하여 주편을 주조하는 방법에 대해서 설명한다. Hereinafter, a method of casting a cast using a casting apparatus according to an embodiment of the present invention.
본 발명의 실시 예에 따른 주조방법은, 턴디쉬(10)에 수용된 용강(60)을 침지 노즐(40)을 통해 몰드(50)로 주입하여 주편(61)을 주조하는 주조방법으로서, 용강(60)과 침지 노즐(40)을 통전시켜 용강 중 함유되는 산소를 침지 노즐 측으로 배출시킬 수 있다. Casting method according to an embodiment of the present invention, as a casting method for casting the cast steel 61 by injecting the molten steel 60 accommodated in the tundish 10 into the mold 50 through the immersion nozzle 40, 60) and the immersion nozzle 40 are energized to discharge oxygen contained in the molten steel to the immersion nozzle side.
주조를 시작하기 전 용강(60)과 침지 노즐(40)을 통전시키기 위한 회로를 구성할 수 있다. 회로 구성은 턴디쉬(10) 내 용강(60)에 제1전극(72)을 침지시키고 배선을 이용하여 제1전극(72)과 제2전극, 즉 노즐 몸체(41)를 연결한다. 그리고 배선을 통해 제1전극(72)과 제2전극을 외부에 설치되는 전원부(70)에 연결한다. A circuit for energizing the molten steel 60 and the immersion nozzle 40 may be configured before starting casting. In the circuit configuration, the first electrode 72 is immersed in the molten steel 60 in the tundish 10, and the first electrode 72 and the second electrode, that is, the nozzle body 41 are connected to each other by using wires. The first electrode 72 and the second electrode are connected to the power supply unit 70 that is installed externally through the wiring.
그리고 주조가 시작되면 턴디쉬(10) 내 용강(60)을 몰드(50)로 주입하고, 전원부(70)를 통해 제1전극(72)과 제2전극인 노즐 몸체(41)에 전원을 인가한다. 이때, 제1전극(72)은 음극으로, 제2전극은 양극이 되도록 설정하여 전류가 제1전극(72)에서 제2전극 측으로 흐르도록 한다. When casting is started, the molten steel 60 in the tundish 10 is injected into the mold 50, and power is supplied to the nozzle body 41, which is the first electrode 72 and the second electrode, through the power supply unit 70. do. At this time, the first electrode 72 is set to be a cathode, and the second electrode is set to be an anode so that current flows from the first electrode 72 to the second electrode side.
전원부(70)를 통해 제1전극(72) 및 제2전극에 인가되는 전원은 0.1 내지 10mA/㎠ 정도의 전류 밀도가 인가되도록 조절할 수 있다. 이는 노즐 몸체(41) 내부에 구비되는 라이너(43)가 이온전도성이 매우 높기 때문에 비교적 작은 크기의 전류가 흐르더라도 산소 이온이 원활하게 이동할 수 있기 때문이다. 이때, 전류 밀도가 제시된 범위보다 작은 경우에는 금속산화물의 이온화 및 산소 이온의 이동이 원활하게 이루어지지 않는다. 또한, 전류 밀도가 제시된 범위 이내에서는 금속산화물의 이온화 및 산소 이온이 이동이 원활하게 이루어지므로, 전류 밀도를 제시된 범위보다 크게 할 필요가 없다. The power applied to the first electrode 72 and the second electrode through the power supply unit 70 may be adjusted to apply a current density of about 0.1 to about 10 mA / cm 2. This is because the liner 43 provided inside the nozzle body 41 has very high ion conductivity, so that oxygen ions can smoothly move even if a relatively small current flows. At this time, when the current density is smaller than the suggested range, the ionization of the metal oxide and the movement of oxygen ions are not performed smoothly. In addition, since the ionization of the metal oxide and the movement of oxygen ions are performed smoothly within the range of the current density, the current density does not need to be larger than the range.
이와 같이 제1전극(72)과 제2전극에 전원이 인가되면, 전자가 제1전극(72)에서 제2전극인 노즐 몸체(41) 측으로 이동하며, 이에 제1전극(72)에서 제2전극 측으로 전류가 흐르게 된다. 도 3을 참조하여 다시 설명하면, 제1전극(72)과 제2전극에 전원이 인가되면, 침지 노즐(40) 내벽 측에 생성된 금속 산화물 주변에 전자가 밀집하게 되고, 전자에 의해 금속 산화물이 산소 이온과 양이온으로 분해된다. 이렇게 분해된 산소 이온은 전자의 이동방향, 즉 용강에서 노즐 몸체(41) 방향으로 이동한다. 이때, 산소 이온은 침지 노즐(40) 내벽에 형성된 라이너(43)를 통해 노즐 몸체(41)로 이동하게 된다. 고체전해질인 라이너(43)는 산소 이온에 대해서만 투과성을 갖기 때문에 양이온은 용강 중으로 용해되어 흡수된다. 이와 같은 과정은 전원이 인가되는 동안 지속적으로 수행되며 침지 노즐(40)의 내벽에 금속 산화물이 생성 및 부착되는 것을 억제 혹은 방지할 수 있다. 따라서 금속 산화물의 생성 및 부착에 의해 발생할 수 있는 노즐 막힘 현상을 방지할 수 있다. When power is applied to the first electrode 72 and the second electrode as described above, electrons move from the first electrode 72 to the nozzle body 41, which is the second electrode, and thus the second electrode from the first electrode 72. Current flows to the electrode side. Referring again to FIG. 3, when power is applied to the first electrode 72 and the second electrode, electrons are concentrated around the metal oxide generated on the inner wall of the immersion nozzle 40, and the metal oxide is caused by the electrons. It decomposes into oxygen ions and cations. The decomposed oxygen ions move in the direction of movement of electrons, that is, in the direction of the nozzle body 41 in the molten steel. At this time, the oxygen ions are moved to the nozzle body 41 through the liner 43 formed on the inner wall of the immersion nozzle 40. Since the liner 43 which is a solid electrolyte has permeability only to oxygen ions, cations are dissolved and absorbed in molten steel. This process is continuously performed while power is applied, and it is possible to suppress or prevent the generation and attachment of metal oxides to the inner wall of the immersion nozzle 40. Therefore, it is possible to prevent nozzle clogging that may occur due to the generation and attachment of metal oxides.
이하에서는 본 발명의 실시 예에 따른 주조 장치를 이용한 시험 결과에 대해서 설명한다. Hereinafter, a test result using a casting apparatus according to an embodiment of the present invention will be described.
시험을 위해 침지 노즐의 내벽 일부에 고체전해질로 라이너를 형성하고, 나머지 부분은 라이너를 형성하지 않은 침지 노즐을 제작하였다. 이렇게 제작된 침지 노즐을 이용하여 용강 13ton 규모의 시험 설비에서 주조를 실시하였다. 이때, 2mA/cm2 의 전류 밀도가 인가되도록 전원을 공급하였다. 그리고 노즐 막힘 현상을 가속화 할 수 있도록 용강 중 Al2O3 개재물이 다량으로 발생할 수 있는 조건을 적용하였다. 이후 시험에 사용된 침지 노즐을 절단하여 그 내부를 관찰하였다. For the test, a liner was formed with a solid electrolyte on a portion of the inner wall of the immersion nozzle, and the immersion nozzle was prepared without the rest of the liner. Casting was performed in a 13 ton scale test facility using the immersion nozzle thus produced. At this time, power was supplied such that a current density of 2 mA / cm 2 was applied. In order to accelerate the nozzle clogging phenomenon, a condition in which a large amount of Al 2 O 3 inclusions in molten steel was generated was applied. Subsequently, the immersion nozzle used for the test was cut and the inside thereof was observed.
실험 결과, 라이너가 적용된 영역에서는 0.3㎜ 이하의 개재물층이 부착되었고, 라이너가 적용되지 않은 영역(B)에서는 개재물과 지금의 혼합으로 1.8 ~ 3.5㎜ 정도의 개재물층이 부착됨을 확인하였다. As a result, it was confirmed that an inclusion layer of 0.3 mm or less was attached in the region where the liner was applied, and an inclusion layer of about 1.8 mm to 3.5 mm was attached by the current mixture in the region B where the liner was not applied.
이와 같은 시험을 통해 침지 노즐에 고체전해질을 포함하는 라이너를 형성하고, 용강과 침지 노즐을 통전시키면 용강 중 산소가 제거되어 침지 노즐 내벽에서 금속 산화물의 생성 및 부착이 억제됨을 확인할 수 있었다. Through this test, when the liner including the solid electrolyte was formed in the immersion nozzle, and the molten steel and the immersion nozzle were energized, it was confirmed that oxygen in the molten steel was removed to suppress the generation and adhesion of metal oxides on the inner wall of the immersion nozzle.
이상에서 본 발명의 바람직한 실시예에 대하여 도시하고 설명하였으나, 본 발명은 상기한 실시예에 한정되지 아니하며, 청구범위에서 청구하는 본 발명의 요지를 벗어남이 없이 당해 본 발명이 속하는 분야에서 통상의 지식을 가진 자라면 이로부터 다양한 변형 및 균등한 타 실시예가 가능하다는 점을 이해할 것이다. 따라서, 본 발명의 기술적 보호범위는 아래의 특허청구범위에 의해서 정하여져야 할 것이다.Although the preferred embodiments of the present invention have been shown and described above, the present invention is not limited to the above-described embodiments, and the general knowledge in the field of the present invention belongs without departing from the gist of the present invention as claimed in the claims. Those skilled in the art will appreciate that various modifications and equivalent other embodiments are possible therefrom. Therefore, the technical protection scope of the present invention will be defined by the claims below.
본 발명에 따른 노즐, 주조장치 및 주조방법은 주편을 주조하는 연속주조공정에서 노즐 막힘 현상을 억제 혹은 방지하여 주편의 생산성을 향상시킬 수 있다. The nozzle, the casting apparatus and the casting method according to the present invention can improve the productivity of the cast by suppressing or preventing the nozzle clogging phenomenon in the continuous casting process for casting the cast.

Claims (16)

  1. 용강이 이동할 수 있는 내공부를 갖고, 상기 용강이 상기 내공부의 외측으로 이동할 수 있는 토출구가 형성되는 노즐 몸체; 및A nozzle body having an inner hole through which molten steel can move, and a discharge hole through which the molten steel can move outwardly of the inner hole; And
    상기 노즐 몸체의 내벽의 적어도 일부를 둘러싸고, 마그네시아 안정화 지르코니아(MgO stabilized ZrO2, MSZ)를 포함하는 라이너; A liner surrounding at least a portion of the inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ);
    를 포함하는 노즐. Nozzle comprising a.
  2. 청구항 1에 있어서,The method according to claim 1,
    상기 노즐 몸체는 Al2O3를 포함하고, The nozzle body comprises Al 2 O 3 ,
    상기 노즐 몸체는 상기 노즐 몸체 전체 중량에 대하여 20중량% 내지 30중량% 의 탄소 성분을 함유하는 노즐. And the nozzle body contains from 20% to 30% by weight of carbon components based on the total weight of the nozzle body.
  3. 청구항 1에 있어서, The method according to claim 1,
    상기 라이너는 마그네시아 안정화 지르코니아 80 내지 95중량%와, 탄소 5 내지 20 중량%를 포함하는 노즐. Wherein the liner comprises 80 to 95 weight percent of magnesia stabilized zirconia and 5 to 20 weight percent of carbon.
  4. 청구항 3에 있어서, The method according to claim 3,
    상기 마그네시아 안정화 지르코니아는 마그네시아(MgO) 8 내지 15mol%를 함유하는 노즐. The magnesia stabilized zirconia is a nozzle containing 8 to 15 mol% of magnesia (MgO).
  5. 청구항 4에 있어서,The method according to claim 4,
    상기 라이너의 길이방향에 대해서 상기 라이너의 상측과 하측 중 적어도 어느 한 쪽에 더미 링이 구비되는 노즐. And a dummy ring provided on at least one of an upper side and a lower side of the liner with respect to the longitudinal direction of the liner.
  6. 청구항 5에 있어서,The method according to claim 5,
    상기 더미 링은 탄소 성분을 포함하는 노즐.And the dummy ring comprises a carbon component.
  7. 청구항 6에 있어서,The method according to claim 6,
    상기 더미 링은 상기 라이너의 길이에 대하여 1~2%의 길이로 형성되는 노즐.The dummy ring is formed with a length of 1 to 2% of the length of the liner.
  8. 주조 장치로서, As a casting device,
    내부에 용강이 수용되는 턴디쉬와;A tundish for receiving molten steel therein;
    상기 턴디쉬 하부에 연결되고, 노즐 몸체와, 상기 노즐 몸체의 내벽의 적어도 일부를 둘러싸고 마그네시아 안정화 지르코니아(MgO stabilized ZrO2, MSZ)를 포함하는 라이너를 포함하는 침지 노즐; 및An immersion nozzle connected to the tundish and including a nozzle body and a liner including at least a portion of an inner wall of the nozzle body and including magnesia stabilized zirconia (MgO stabilized ZrO 2 , MSZ); And
    상기 턴디쉬에 수용된 용강과 상기 노즐 몸체를 통전시키는 전원부;를 포함하는 주조 장치. And a power supply unit for energizing the molten steel accommodated in the tundish and the nozzle body.
  9. 청구항 8에 있어서,The method according to claim 8,
    상기 노즐 몸체는 Al2O3를 포함하고, The nozzle body comprises Al 2 O 3 ,
    상기 노즐 몸체는 상기 노즐 몸체 전체 중량에 대하여 20중량% 내지 30중량% 의 탄소 성분을 함유하며, The nozzle body contains 20 to 30% by weight of the carbon component relative to the total weight of the nozzle body,
    상기 라이너는 8 내지 15mol%의 마그네시아(MgO)를 함유하는 마그네시아 안정화 지르코니아 80 내지 95중량%와, 탄소 5 내지 20 중량%를 포함하는 주조 장치. The liner comprises 80 to 95 weight percent of magnesia stabilized zirconia containing 8 to 15 mol% magnesia (MgO) and 5 to 20 weight percent carbon.
  10. 청구항 9에 있어서,The method according to claim 9,
    상기 라이너의 길이방향에 대해서 상기 라이너의 상측과 하측 중 적어도 어느 한 쪽에 더미 링이 구비되는 주조 장치.Casting apparatus provided with a dummy ring on at least one of the upper side and the lower side of the liner with respect to the longitudinal direction of the liner.
  11. 청구항 8에 있어서,The method according to claim 8,
    상기 턴디쉬 내 용강에 침지되는 전극을 포함하고, An electrode immersed in the molten steel in the tundish,
    상기 전원부는 상기 전극 및 상기 침지 노즐에 전원을 인가하는 주조 장치. The power supply unit is a casting device for applying power to the electrode and the immersion nozzle.
  12. 턴디쉬에 수용된 용강을 침지 노즐을 통해 몰드로 주입하여 주편을 주조하는 주조방법으로서, A casting method for casting cast steel by injecting molten steel contained in a tundish into a mold through an immersion nozzle,
    상기 침지 노즐은 상기 턴디쉬에 연결되는 노즐 몸체와, 상기 노즐 몸체 내벽에 구비되고 마그네시아 안정화 지르코니아를 함유하는 라이너를 포함하고, The immersion nozzle includes a nozzle body connected to the tundish and a liner provided on the inner wall of the nozzle body and containing magnesia stabilized zirconia,
    상기 용강과 상기 노즐 몸체를 통전시켜 상기 용강 중 함유되는 산소를 상기 침지 노즐 측으로 배출시키는 주조 방법. A casting method for energizing the molten steel and the nozzle body to discharge oxygen contained in the molten steel to the immersion nozzle side.
  13. 청구항 12에 있어서,The method according to claim 12,
    상기 용강과 상기 노즐 몸체가 통전되면, 상기 용강 중 생성된 금속산화물이 산소이온과 양이온으로 분해되고, When the molten steel and the nozzle body is energized, the metal oxide generated in the molten steel is decomposed into oxygen ions and cations,
    상기 산소이온이 상기 라이너를 통해 상기 노즐 몸체로 이동하여 상기 용강 중 산소가 침지 노즐 측으로 배출되는 주조 방법. The oxygen ion is moved to the nozzle body through the liner to cast oxygen out of the molten steel to the immersion nozzle side.
  14. 청구항 13에 있어서,The method according to claim 13,
    상기 용강은 음극으로, 상기 침지 노즐은 양극으로 하여 통전시키는 주조 방법. The molten steel is a cathode, the immersion nozzle is an anode, the current is passed through.
  15. 청구항 14에 있어서, The method according to claim 14,
    상기 용강과 상기 침지 노즐을 통전시키는 과정에서 0.1 내지 10mA/㎠의 전류 밀도가 인가되도록 통전시키는 주조 방법. Casting method so that the current density of 0.1 to 10mA / ㎠ is applied in the process of energizing the molten steel and the immersion nozzle.
  16. 청구항 13에 있어서,The method according to claim 13,
    상기 라이너의 상측 및 하측의 적어도 한 쪽에는 더미링이 구비되고, At least one of the upper side and the lower side of the liner is provided with a dummy ring,
    상기 더미링은 상기 주편을 주조하는 과정에서 용해되어 공간을 형성하는 주조 방법.The dummy ring is melted in the process of casting the cast piece to form a space.
PCT/KR2015/014134 2015-11-27 2015-12-22 Nozzle, casting device, and casting method WO2017090819A1 (en)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108145144A (en) * 2017-12-27 2018-06-12 武汉科技大学 A kind of ladle working lining for controlling molten steel slag
EP3827912B1 (en) * 2019-11-26 2022-03-30 Refractory Intellectual Property GmbH & Co. KG An exchangeable nozzle for a nozzle changer system, a method for manufacturing such a nozzle, a nozzle changer system comprising such a nozzle and a tundish comprising such a nozzle changer system

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109909466B (en) * 2019-03-19 2023-12-19 沈阳麒飞新型材料科技有限公司 Continuous pouring equipment with multiple water gaps
CN111036891A (en) * 2019-11-29 2020-04-21 浙江科宇金属材料有限公司 Pouring pipe for vertical casting
JP7393638B2 (en) 2020-01-17 2023-12-07 日本製鉄株式会社 Continuous steel casting method
CN111482589B (en) * 2020-04-28 2023-05-09 宋振亚 Manufacturing method of long-service-life metering nozzle

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003040672A (en) * 2001-05-21 2003-02-13 Shinagawa Refract Co Ltd Refractory used for fireproof member for continuous steel casting
JP2010167481A (en) * 2009-01-26 2010-08-05 Kurosaki Harima Corp Nozzle for continuous casting
KR20130010392A (en) * 2011-07-18 2013-01-28 주식회사 포스코 Apparatus for molten metal treatment
KR20140041897A (en) * 2011-12-01 2014-04-04 구로사키 하리마 코포레이션 Refractory and nozzle for casting
KR101489377B1 (en) * 2013-12-06 2015-02-03 주식회사 포스코 Apparatus for molten metal treatment and method for molten metal treatment

Family Cites Families (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2056430B (en) * 1979-08-18 1982-12-08 Akechi Taikarenga Kk Immersion nozzle for continuous casting of molten steel
JPS5785659A (en) * 1980-11-18 1982-05-28 Kawasaki Steel Corp Preventive method for deposition of alumina from molten steel flow and nozzle for molten steel
JPH0775763B2 (en) * 1985-10-25 1995-08-16 住友化学工業株式会社 Nozzle for continuous casting
JPS62192254A (en) * 1986-02-17 1987-08-22 Sumitomo Metal Ind Ltd Device for preventing clogging of molten metal flow passage
DE3842690C2 (en) * 1988-12-19 1998-04-30 Didier Werke Ag Refractory connection and induction coil therefor
JPH0722808B2 (en) * 1988-12-27 1995-03-15 住友金属工業株式会社 Method for preventing deposition of deposits on the immersion nozzle
JPH08132193A (en) * 1994-10-31 1996-05-28 Akechi Ceramics Kk Nozzle for continuous casting
JPH08155601A (en) * 1994-12-07 1996-06-18 Nippon Steel Corp Nozzle for continuous casting
DE19923800C1 (en) * 1999-05-19 2001-03-22 Sms Demag Ag Method and device for holding and tapping molten metal
JP4150142B2 (en) * 1999-12-13 2008-09-17 新日本製鐵株式会社 Sliding nozzle of metallurgical container
JP4231176B2 (en) * 1999-12-13 2009-02-25 新日本製鐵株式会社 Stopper for metallurgy container and / or upper nozzle
JP3506655B2 (en) * 2000-04-28 2004-03-15 明智セラミックス株式会社 Continuous casting nozzle
JP3747848B2 (en) * 2000-12-25 2006-02-22 住友金属工業株式会社 Continuous casting method
JP3896908B2 (en) * 2002-06-21 2007-03-22 住友金属工業株式会社 Continuous casting method for molten steel
JP4282005B2 (en) * 2004-01-19 2009-06-17 黒崎播磨株式会社 Immersion nozzle and method of manufacturing the immersion nozzle
JP4533051B2 (en) * 2004-09-06 2010-08-25 黒崎播磨株式会社 Continuous casting nozzle having an inner hole
CN101176914A (en) * 2006-11-10 2008-05-14 宝山钢铁股份有限公司 Method for preventing cast steel stove continuous casting water gap from obstruction and reducing erosion
JP5088400B2 (en) * 2010-06-18 2012-12-05 住友金属工業株式会社 Steel continuous casting method
WO2013190594A1 (en) * 2012-06-20 2013-12-27 新日鐵住金株式会社 Submerged entry nozzle for continuous casting and continous casting method using same
JP5818037B2 (en) * 2014-02-28 2015-11-18 品川リフラクトリーズ株式会社 Immersion nozzle for continuous casting

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003040672A (en) * 2001-05-21 2003-02-13 Shinagawa Refract Co Ltd Refractory used for fireproof member for continuous steel casting
JP2010167481A (en) * 2009-01-26 2010-08-05 Kurosaki Harima Corp Nozzle for continuous casting
KR20130010392A (en) * 2011-07-18 2013-01-28 주식회사 포스코 Apparatus for molten metal treatment
KR20140041897A (en) * 2011-12-01 2014-04-04 구로사키 하리마 코포레이션 Refractory and nozzle for casting
KR101489377B1 (en) * 2013-12-06 2015-02-03 주식회사 포스코 Apparatus for molten metal treatment and method for molten metal treatment

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108145144A (en) * 2017-12-27 2018-06-12 武汉科技大学 A kind of ladle working lining for controlling molten steel slag
CN108145144B (en) * 2017-12-27 2023-08-15 武汉科技大学 Ladle working lining for controlling molten steel slag winding
EP3827912B1 (en) * 2019-11-26 2022-03-30 Refractory Intellectual Property GmbH & Co. KG An exchangeable nozzle for a nozzle changer system, a method for manufacturing such a nozzle, a nozzle changer system comprising such a nozzle and a tundish comprising such a nozzle changer system

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