CN210498296U

CN210498296U - Device for adding heated solid-state covering slag into crystallizer in continuous casting process

Info

Publication number: CN210498296U
Application number: CN201921675102.8U
Authority: CN
Inventors: 艾新港; 韩东; 李胜利; 刘海啸; 宁哲; 张家伟; 马帅
Original assignee: University of Science and Technology Liaoning USTL
Current assignee: University of Science and Technology Liaoning USTL
Priority date: 2019-10-09
Filing date: 2019-10-09
Publication date: 2020-05-12
Anticipated expiration: 2029-10-09

Abstract

The utility model relates to a device of solid-state covering slag of heating is added to crystallizer in continuous casting process, including continuous casting crystallizer and crystallizer platform, its characterized in that is equipped with dolly actuating system on the right side of continuous casting crystallizer, is equipped with covering slag heating system on dolly actuating system's upper portion, and dolly actuating system includes braced frame, motor, power input output wire, dolly promotion handle and the dolly drive wheel of dolly bottom plate, covering slag heating rectangle unit, covering slag heating system including adding sediment funnel, covering slag heating rectangle unit, hydraulic press, forced induction valve and fixed bolster. The device for adding the heating solid-state covering slag into the crystallizer is used for heating the solid-state covering slag, so that the superheat degree of molten steel is reduced due to the fact that the covering slag absorbs too much heat of the molten steel, the meniscus position of the crystallizer can be kept at a high temperature, the vibration mark hooks are relatively shallow, impurities and bubbles are not easy to adsorb, the surface quality of a casting blank is improved, and the pollution to the environment is reduced.

Description

Device for adding heated solid-state covering slag into crystallizer in continuous casting process

Technical Field

The utility model belongs to the technical field of the iron and steel is smelted, especially, relate to a device that adds solid-state covering slag of heating to the crystallizer at the continuous casting in-process.

Background

The casting powder is required to be added into the crystallizer in the continuous casting process of the molten steel, and the casting powder has the functions of controlling heat transfer, lubricating, absorbing impurities, preventing secondary oxidation of the molten steel and insulating heat. The mold flux for industrial production at present is a pre-melted type solid powder slag which basically meets the requirements of continuous casting production, but has problems such as that the solid mold flux added into the mold needs to absorb the temperature of molten steel to be melted, resulting in a decrease in the temperature of the molten steel. The temperature reduction of the molten steel brings about a series of adverse effects, such as the formation of deeper meniscus hooks at the meniscus, the adsorption of inclusions and Ar bubbles, etc., and the deterioration of the surface quality of the cast slab. In addition, the temperature reduction of the molten steel in the continuous casting process can promote the growth of a slag ring, the slag ring can prevent molten slag from flowing into a gap between the wall of the crystallizer and the wall of the blank shell, and even can block a molten slag channel, so that the thickness of a slag film between the blank shell and the wall of the crystallizer is uneven, the lubrication is poor, and further the quality problem of a casting blank is caused, and accidents such as bonding steel leakage and the like are caused. In addition, in order to ensure good fluidity and low melting temperature of the mold flux, F is generally added to the mold flux^-、Na⁺And harmful ions and the like pollute the environment. In view of the above problems, there have been proposed the use of liquid mold flux continuous casting, in which the mold flux is melted outside a mold and then fed into the mold. Because the temperature of the liquid casting powder is higher, the liquid casting powder does not need to be heatedWhen the temperature of molten steel is molten, the temperature drop speed at the meniscus is slowed down, so that the formed meniscus hook is shallow, and the quality of a casting blank is improved. Meanwhile, the heat brought by the liquid protection slag makes the slag ring smaller, the permeation channel is enlarged, the consumption of the slag is increased, and the lubricating effect is improved. However, the liquid mold flux is difficult to produce and use, has strict requirements on a heating container and a transmission pipeline, and has high temperature and high danger. At present, the continuous casting by using the liquid mold flux is still in a test stage, and can not be applied to actual production of factories in a large scale. Therefore, the problem that the continuous casting covering slag absorbs the heat of molten steel to cause defects of casting blanks, the problem that continuous casting does not run smoothly and the like is concerned by the current scholars.

Patent publication No.: CN109676101A discloses a continuous casting crystallizer nano covering slag and a preparation method thereof. Spherical nano particles with the volume ratio of 0.1-50% are doped in the covering slag, wherein the spherical nano particles have the advantages of high heat conductivity coefficient, good sphericity, proper particle size and the like, so that uniform and stable nanofluid can be formed in the liquid covering slag, the interface energy between the spherical nano particles and the solid covering slag is high enough, and the van der Waals acting force is low enough, so that the nano particles can be uniformly distributed in the liquid covering slag without obvious agglomeration, and the covering slag can be added to form the continuous casting crystallizer nano covering slag, has excellent heat transfer performance and lubricating performance, can improve the quality of a casting blank, and is suitable for producing products with special specifications (such as extra-thick plates) and products with special continuous casting processes (such as ultrahigh casting speed). However, the solid mold flux at normal temperature is added, so that the heat of the molten steel is consumed for melting, the temperature of the molten steel is reduced, a long meniscus hook is formed, impurities are adsorbed, and the quality of a casting blank is influenced. The nano-casting powder prepared by utilizing the spherical nano-particles has good heat transfer performance, can improve the cooling effect of the crystallizer, but also can cause the temperature of the upper surface of molten steel to be lost more quickly due to better heat transfer performance, and is more beneficial to the growth of meniscus hooks. In addition, the use of the nano mold flux continuous casting will raise the cost to some extent for the production of steel grades of ordinary specifications. Moreover, the preparation process of the nano mold flux is complex, spherical nano particles are firstly dispersed, then the dispersed spherical nano particles are added into a mold flux matrix, and then high-energy ball milling is carried out, wherein the longest time of the high-energy ball milling can reach 2 hours.

Patent publication No.: CN 109604548A, discloses a special multifunctional crystallizer covering slag for high pulling speed of thin slabs and a preparation method thereof. The covering slag comprises, by weight, 26-35 parts of CaO and 20-30 parts of SiO₂3-8 parts by weight of Al₂O₃0.5 to 2 parts by weight of Li₂O, 3-8 parts of MgO and 5-11 parts of Na₂O, 6-12 parts by weight of F and 1-8 parts by weight of C. The covering slag can better control the heat transfer capacity and the lubricating capacity in a compatible manner, can meet the requirements of low-carbon steel, medium-carbon steel and peritectic steel continuous casting processes, and has the advantages of simple preparation method and easy operation. However, the mold flux is at normal temperature, and still needs to absorb the heat of molten steel to melt, so that a slag ring is formed above a meniscus, a slag flowing channel is blocked, the lubricating effect is poor, and the continuous casting is influenced. In addition, in order to be compatible with heat transfer and lubricating performance, harmful ions such as F-, Na + and the like are added into the casting powder, so that the environment is polluted. Meanwhile, the covering slag has large application limitation and is only suitable for thin slabs with high drawing speed, particularly the drawing speed is more than 4.5 m/min.

Patent publication No.: CN 109332618A discloses a billet continuous casting covering slag adding device and a continuous casting method thereof. The slag adding device is invented for ensuring a protective slag liquid slag layer with enough thickness, avoiding the contact between a primary solidified blank shell on the upper part of a crystallizer copper pipe and a protective slag molten layer with high carbon content and preventing the surface of a casting blank from being carburized. This covering slag adds sediment device includes the covering slag house steward and sets up the bipartition branch pipe with the covering slag house steward intercommunication in covering slag house steward upper end, and bipartition branch pipe becomes the Y font with the covering slag house steward, guarantees the interior powder slag layer thickness uniformity of crystallizer, forms the covering slag liquid slag layer that thickness is unanimous, has avoided the covering slag to pile up in the crystallizer part, the uneven problem of liquid slag layer thickness. Although the thickness of the liquid slag layer of the casting slag can be uniform by the slag adding device, the solid casting slag at normal temperature is added, the thickness of the molten slag layer formed by melting depends on the heat absorbed by molten steel, the superheat degree of the molten steel is certain, and the amount of the molten casting slag which can be melted is certain, so that the thickness of the liquid slag layer is not increased, the thickness of the liquid slag layer cannot be increased, namely, the slag consumption cannot be increased, the lubricating effect is not improved, and the risk of steel leakage exists. In addition, the device is complex to operate, has limitation in application and is only suitable for continuous casting of small square billets.

Patent publication No.: CN 109465413A discloses a method for distributing casting powder of a single-point non-equilibrium casting beam blank crystallizer. Obtaining a single-point casting model of the crystallizer through mathematical modeling, then simulating the model to obtain the temperature distribution condition of the molten steel on the cross section during the single-point casting of the crystallizer, and determining seven addition points of the covering slag according to the temperature distribution condition of the cross section of the crystallizer. The material distribution method selects two types of covering slag with different melting points, can solve the problems that the temperature distribution of the casting liquid surface is not uniform, the temperature difference of the casting section is large, the melting amount of the covering slag in a high-temperature area is large, the proportion of liquid slag is large, and the covering slag layer is unstable when single-point casting is carried out, enables the covering slag of the crystallizer to be uniformly dissolved, and obtains a good covering slag layer. However, the method requires mold flux with different melting points, and because the added mold flux is solid mold flux at normal temperature, the melting point and melting time of the mold flux can be controlled only by adding extra CaF₂And carbon black to control the melting characteristics of the mold flux, and CaF₂The increase of the content of the spinel (3CaO 2 SiO)₂·CaF₂) The separation of substances with high melting points and the like damages the glass property of slag, seriously deteriorates the lubricating condition, causes the quality problem of casting blanks and even the occurrence of steel leakage accidents due to bonding, and in addition, F^-Too high a content can cause severe erosion of the immersion water.

Patent publication No.: CN 109351928A discloses a method for preventing the surface longitudinal cracks of a hypo-peritectic steel casting blank. During the solidification of the sub-peritectic steel, delta Fe → gamma Fe phase transformation occurs in a peritectic region (L + delta → gamma), large volume shrinkage is generated, a solidified blank shell is separated from a crystallizer copper plate to form an air gap, the heat transfer rate from the blank shell to the crystallizer is reduced, the blank shell becomes thin, and a recess is formed on the surface. Meanwhile, because the thickness of the blank shell is uneven, the weakest part of the solidified blank shell generates crack stress concentration lines under the action of thermal stress, friction force, ferrostatic pressure and the like. The process method adopted by the prior art mainly adopts high-alkalinity crystalline mold flux to achieve the purposes of slowing down heat transfer and reducing cracks. However, too high a crystallization rate tends to deteriorate the lubrication of the cast slab, resulting in slab sticking and breakout. The invention provides a method for preventing longitudinal cracks on the surface of a hypo-peritectic steel casting blank, which is characterized in that casting powder with the alkalinity of 1.2-1.4 and the viscosity of 0.08-0.14 Pa.s at 1300 ℃ is adopted in the continuous casting process, the water quantity of a crystallizer is reduced by 5% -10%, the water inlet temperature of the crystallizer is controlled to be 28-35 ℃, and the lubrication effect of the casting powder is reduced after the alkalinity of the casting powder is increased, so that the negative slip time is reduced by adopting non-sinusoidal vibration and a vibration mode with high vibration frequency and small amplitude, the lubrication is improved, and the longitudinal cracks on the surface of the hypo-peritectic steel casting blank are prevented. The core of the method is that the alkalinity of the casting powder is expected to be improved, the viscosity of the casting powder is not changed, and the viscosity of the casting powder is in direct proportion to the consumption of the quantity of the casting powder, but because the casting powder at normal temperature is used, the casting powder is melted by absorbing the heat of molten steel, the superheat degree of the molten steel is certain, so that the thickness of a formed liquid slag layer is certain, the effect of reducing the viscosity is not achieved, the fluidity of the casting powder is poor, the lubricating effect is poor, and the quality of a casting blank is poor. Therefore, the patent needs to adopt the covering slag meeting the requirements, adjust the water quantity of the crystallizer, control the water inlet temperature of the crystallizer, change a series of parameters such as the vibration form of the crystallizer and the like, and has higher operation difficulty.

Patent publication No.: CN 101479061 a, discloses a continuous casting machine and a continuous casting method using molten mold flux. The continuous casting machine includes: a mold cover, a mold flux melting unit, and a mold flux delivery unit, wherein the mold flux delivery unit includes an injection tube and an injection tube heater. The continuous casting method comprises the following steps: the casting powder used in the continuous casting process is melted outside the crystallizer, and the liquid casting powder is added to the molten steel surface of the crystallizer through a molten casting powder continuous casting machine, so that slag blocks are effectively removed, the consumption of the casting powder is greatly increased, and the lubricating effect is good. However, the liquid mold flux has high requirements on high temperature resistance, corrosion resistance and tightness of a container and a transmission pipeline, and platinum or platinum alloy is required to be used at the joint or contact part of an injection pipe and the injection pipe, so that the cost is extremely high. In addition, the liquid mold flux in a high temperature state has a high risk, and the slag adding operation needs to be performed with great care. The method is in a test stage at present and is not applied to industrial production.

Patent publication No.: CN 105750519 a discloses a method and a device for improving the surface quality of a continuous casting blank by adding molten mold flux. A crystallizer liquid covering slag adding system is arranged above a crystallizer, the system adopts a medium-frequency induction heating technology to melt solid covering slag and heat the solid covering slag to a certain temperature, a stopper rod is adopted to control the outflow of the liquid covering slag, the liquid covering slag is added into the crystallizer after passing through a liquid covering slag distributor and a flow guide pipe, and a full-liquid covering slag layer is formed on the upper part of the steel water of the crystallizer. Meanwhile, a crystallizer heat-insulating cover is additionally arranged at the upper part of the crystallizer, so that the radiation heat loss at the upper part of the crystallizer is reduced. In the continuous casting process, the addition of the casting powder is controlled according to the thickness of the liquid slag layer, so that the surface quality of the casting blank can be improved. However, the liquid mold flux has high fluidity and is very difficult to control, the amount of outflow of the liquid mold flux is difficult to accurately control by using the stopper rod, the flux leaks easily, and the requirements on the performance of the heating container and the pipeline are high. In addition, the medium frequency induction heating technology that this patent adopted needs the water cooling system, and liquid covering slag and molten steel meet the water and explode easily, and danger is higher. Moreover, the present invention does not refer to a detailed distribution manner, and cannot ensure that the liquid mold flux flowing into the mold is rapidly and uniformly spread over the surface of the molten steel. The method is still in a test stage at present and is not applied to industrial production.

At present, the mold flux used in the continuous casting production is still solid mold flux at normal temperature, the mold flux meets the continuous casting requirements of most steel grades, but the problems of poor casting blank quality, unsmooth continuous casting and the like still exist, and the mold flux is particularly applied to high-performance steel grades in high-end technical fields, such as high-manganese high-aluminum steel. In addition, the reduction of the temperature of the molten steel causes the slag ring to expand, blocks a slag flowing channel, causes the lubricating effect to be poor, and further causes the problems of casting blank quality, non-smooth continuous casting and the like. Although the methods mentioned in the above patents alleviate the casting blank quality problem and the continuous casting non-smooth problem caused by the reduction of molten steel to a certain extent, the methods all have certain defects and application limitations, such as complex operation, high cost, high risk and the like, and are not applied to industrial production at present.

Disclosure of Invention

An object of the utility model is to provide a device of adding heating solid-state covering slag to the crystallizer at the continuous casting in-process can make crystallizer meniscus position maintain the higher temperature, and the trace hook that shakes is relatively shallow, is difficult for adsorbing and mix with and the bubble, improves the method and the device of casting blank surface quality's adding heating solid-state covering slag to the crystallizer at the continuous casting in-process.

The purpose of the utility model is realized like this.

The utility model relates to a device for adding heating solid-state covering slag into a crystallizer in the continuous casting process, which comprises a continuous casting crystallizer and a crystallizer platform, and is characterized in that a trolley driving system is arranged on the right side of the continuous casting crystallizer, a covering slag heating system is arranged on the upper part of the trolley driving system,

the trolley driving system comprises a trolley bottom plate, a supporting frame of a rectangular covering slag heating unit, a motor, a power input lead and a power output lead, a trolley pushing handle and a trolley driving wheel, wherein the supporting frame is arranged on the trolley bottom plate;

the casting powder heating system comprises a casting powder feeding funnel, a casting powder heating rectangular unit, a hydraulic machine, a pressure sensing valve and a fixed support, wherein the fixed support and the hydraulic machine are respectively fixed on the upper portion of a supporting frame, the casting powder heating rectangular unit is obliquely arranged on the upper portion of the supporting frame through the fixed support and the hydraulic machine, the casting powder feeding funnel is arranged at the upper feeding end of the casting powder heating rectangular unit, the discharging end of the lower portion of the casting powder heating rectangular unit is arranged on the upper portion of a crystallizer platform, and the pressure sensing valve is arranged at the discharging end of the lower portion of the casting powder heating rectangular unit.

As a further optimization of the utility model, the covering slag heating rectangle unit constitute by covering slag heating chamber, corrosion resistant plate, asbestos protective layer, heat conduction copper and heating element, corrosion resistant plate and asbestos protective layer set up on the upper portion of covering slag heating chamber, heat conduction copper and heating element set up in the lower part of covering slag heating chamber, are equipped with a plurality of temperature thermocouple in the symmetry respectively in the upper portion and the lower part of covering slag heating chamber.

As a further optimization of the utility model, the asbestos thickness is S₁0.01-0.03 m, and its heat conductivity is lambda₁0.16-0.37W/m DEG C; the melting point of the stainless steel plate is 1300-1600 ℃, and the thickness S of the stainless steel plate is₂0.005-0.02 m, and a thermal conductivity lambda₂10-30W/m DEG C; the bottom area of the covering slag heating chamber is A, m²The thickness H is 0.1 m-0.5 m; the melting point T of the heat-conducting copper plate is 800-1100 ℃; the thermal conductivity of each of the above materials is a thermal conductivity at 300 ℃.

As a further optimization of the utility model, the inclination angle of the rectangular unit for heating the mold powder is β degrees, namely the rectangular unit for heating the mold powder is 0 to 90 degrees with the horizontal angle β.

The utility model has the advantages that: because the utility model discloses adopted the above-mentioned device of adding heating solid-state covering slag to the crystallizer at the continuous casting in-process, alleviate the covering slag and absorbed too many heats of molten steel and lead to the superheat degree of molten steel to reduce, cause the meniscus hook to adsorb inclusion and produce big slag circle and block up the slag flowing channel, and then bring harmful effects for casting blank quality and continuous casting antegrade, can make crystallizer meniscus position maintain higher temperature, the mark hook that shakes is relatively shallow, difficult absorption is mingled with and the bubble, improve casting blank surface quality, reduce the pollution to the environment.

Drawings

FIG. 1 is a schematic structural view of a device for adding heated solid mold flux to a mold in a continuous casting process according to the present invention.

Fig. 2 is a schematic structural view of a mold flux heating rectangular unit.

The specific implementation mode is as follows:

the present invention will be further described with reference to the accompanying drawings.

As shown in fig. 1 and 2, the device for adding heated solid mold flux to a mold in a continuous casting process of the present invention comprises a continuous casting mold C and a mold platform, and is characterized in that a trolley driving system B is provided on the right side of the continuous casting mold C, a mold flux heating system a is provided on the upper portion of the trolley driving system B,

the trolley driving system B comprises a trolley bottom plate 27, a supporting frame 21 of a rectangular covering slag heating unit arranged on the trolley bottom plate 27, a motor 22 arranged in the supporting frame 21, a power input lead 23 and a power output lead 24 which are respectively connected with the motor at the same time, a trolley pushing handle 25 arranged on the trolley bottom plate 27 and a trolley driving wheel 26 arranged at the lower part of the trolley bottom plate, wherein the power input lead 24 is connected with an external power supply, and the power output lead 24 is connected with a covering slag heating system A;

the casting powder heating A system comprises a casting powder adding funnel 11, a casting powder heating rectangular unit 12, a hydraulic machine 13, a pressure sensing valve 14 and a fixed support 15, wherein the fixed support 15 and the hydraulic machine 13 are respectively fixed on the upper portion of a supporting frame 21, the casting powder heating rectangular unit 12 is obliquely arranged on the upper portion of the supporting frame 21 through the fixed support 15 and the hydraulic machine 13, the casting powder adding funnel 11 is arranged at the upper feeding end of the casting powder heating rectangular unit, the discharging end of the lower portion of the casting powder heating rectangular unit is arranged on the upper portion of a crystallizer platform, and the pressure sensing valve 14 is arranged at the discharging end of the lower portion of the casting powder heating rectangular unit.

As shown in fig. 2, the rectangular mold flux heating unit 12 according to the present invention is composed of a mold flux heating chamber 123, a stainless steel plate 122, an asbestos-protecting layer, and a heat-conducting copper plate 124 as a heating element 125, wherein the stainless steel plate 122 and the asbestos-protecting layer 121 are disposed on the upper portion of the mold flux heating chamber 123, the heat-conducting copper plate 124 and the heating element 125 are disposed on the lower portion of the mold flux heating chamber 123, and a plurality of temperature thermocouples 126 are symmetrically disposed on the upper portion and the lower portion of the mold flux heating chamber 123, respectively.

Example 1

The steel grade produced by the test is 20Mn23AlV, and the components of the casting powder are 23 percent of CaO and SiO₂46% of CaF₂10% of Mg, 6% of Mg and Na ₂15% of O, 0.60 pas of viscosity η at 1300 ℃ and 700kg/m of density rho³(ii) a Drawing speed v_cControlling the thickness of casting blank to be 0.60m/min, controlling the section of casting blank to be 200X 1200mm, controlling the vibration range H to be 7.20mm, controlling the vibration frequency f to be 146Hz, controlling the thickness of α to be 20 percent, controlling the thickness of mu to be 90 percent, controlling the thickness of heating chamber H to be 0.2m, and controlling the thicknesses of asbestos and stainless steel plate to be S respectively₁＝0.02m、S₂0.01 m; the heat conductivity coefficients of the asbestos protective layer 121, the stainless steel plate 122 and the air are respectively lambda₁＝0.214W/m·℃、λ₂＝16W/m·℃、λ₃The melting point of the copper heat-conducting plate 124 used is 1000 ℃.

The method comprises the following steps:

step 1: before the start of continuous casting, solid mold flux is added to the mold flux heating chamber 123 through the flux adding hopper 11 so that the mold flux heating chamber 123 is filled with the solid mold flux. Determining the heating temperature T of the covering slag according to the melting point of the heat-conducting copper plate₀1000 ℃ and 200 ℃ respectively; then selecting a heating power of 1kw to heat the rectangular unit (A2) for heating the covering slag;

step 2: nine positions a, b, c, d, e, f, g, h and i of the rectangular covering slag heating unit 12 are respectively provided with a temperature thermocouple 126, and when the temperatures of the three points d, e and f reach 800 ℃, namely T_d＝800℃、T_e＝800℃、T_fHeating was stopped at 800 ℃ and the temperatures at six positions a, b, c, g, h, i were measured to obtain T_a＝103℃、T_b＝101℃、T_c＝96℃、T_g＝1011℃、T_h＝995℃、T_i994 ℃. The obtained temperature values are substituted into the following formula (2), formula (3), and formula (4).

In the above formula, T_a、T_b、T_c、T_d、T_e、T_f、T_g、T_h、T_iIs the temperature (see FIG. 2 in the description of the drawings), T, of each position₁Indicating the average temperature, T, of the upper surface of the asbestos-protecting layer 121₂Represents the average temperature, T, of the mold flux₃Represents the average temperature of the lower surface of the heating element 125 where it contacts the air;

calculating to obtain T₁＝100℃、T₂＝800、T₃＝1000℃。

And step 3: calculating the power P required for heating the casting powder to 800 ℃ according to the formula (1) to be 15.28 kw;

and 4, when continuous casting starts, heating the casting powder heating unit 12 by using the heating power P of 15.28kw, finishing heating when the temperature of the casting powder reaches 800 ℃, starting the hydraulic machine 13, increasing β, opening the pressure sensing valve 14, and allowing the casting powder to fall to the crystallizer platform 33 under the action of gravity.

Example 2

The steel grade produced by the test is Q235B, and the components of the casting powder are CaO 27.5 percent and SiO₂45.5% of Al₂O₃7.0% of CaF₂6.0% of MgO, 3.0% of Na₂9.5% of O and Li₂O is 1.5%, viscosity η is 0.55 pas at 1300 deg.C, density rho is 681kg/m³(ii) a Drawing speed v_cControlling the thickness of the casting blank to be 0.80m/min, controlling the section of the casting blank to be 200 multiplied by 1200mm, controlling the vibration range H to be 7.20mm, controlling the vibration frequency f to be 146Hz, controlling the thickness of α to be 20 percent, controlling the thickness of mu to be 90 percent, controlling the thickness of a heating chamber H to be 0.4m, and controlling the thicknesses of an asbestos protective layer 121 and a stainless steel plate 122 to be S respectively₁＝0.02m、S₂0.01 m; the heat conductivity coefficients of the asbestos protective layer 121, the stainless steel plate 122 and the air are respectively lambda₁＝0.214W/m·℃、λ₂＝16W/m·℃、λ₃The melting point of the copper heat-conducting plate 124 used is 900 deg.c, 0.024W/m deg.c.

The method comprises the following steps:

step 1: before the start of continuous casting, solid mold flux is added to the mold flux heating chamber 123 through the flux adding hopper 11 to fill the heating chamber 123 with the solid mold flux, and the mold flux heating temperature T is determined based on the melting point of the heat conductive copper plate 124₀900 ℃ and 200 ℃ respectively; then selecting a heating rectangular unit 12 with heating power of 1kw for heating the covering slag;

step 2: nine positions a, b, c, d, e, f, g, h and i of the rectangular unit for heating the covering slag are respectively provided with a temperature thermocouple 126, and when the temperatures of the three points d, e and f reach 700 ℃, namely T_d＝800℃、T_e＝800℃、T_fHeating was stopped at 800 ℃ and the temperatures at six positions a, b, c, g, h, i were measured to obtain T_a＝84℃、T_b＝81℃、T_c＝78℃、T_g＝998℃、T_h＝989℃、T_i983 ℃. Substituting the temperature values into formulas (2), (3) and (4) to obtain T₁＝81℃、T₂＝700、T₃＝990℃。

In the above formula, T_a、T_b、T_c、T_d、T_e、T_f、T_g、T_h、T_iThe temperatures at the various locations (see fig. 2 in the description of the figures) are indicated by the average temperature of the upper surface of the asbestos protective layer 121, by the average temperature of the mold flux, and by the average temperature of the lower surface of the heating element 125 in contact with the air.

And step 3: calculating the power P required for heating the casting powder to 700 ℃ according to the formula (1) to be 13.65 kw;

and 4, when continuous casting starts, heating the mold flux heating unit 12 by using the heating power P of 13.65kw, finishing heating when the temperature of the mold flux reaches 800 ℃, starting the hydraulic machine 13, increasing β, opening the pressure sensing valve 14, and allowing the mold flux to fall to a crystallizer platform 33 under the action of gravity, wherein 31 is the wall of the crystallizer and 32 is molten steel.

The utility model discloses a heating device heats solid-state covering slag to the uniform temperature, then adds in the crystallizer in succession. Because the heated casting powder slag has certain heat, the casting powder slag can be melted only by absorbing less heat from the molten steel to form a smaller slag ring, a slag infiltration channel is enlarged, the consumption of the slag is increased, the lubricating effect is better, the bonding and steel leakage are prevented, and the smooth continuous casting is facilitated. In addition, the heated casting powder can maintain the position of a meniscus of the crystallizer at a higher temperature, the vibration mark hooks are relatively shallow, impurities and air bubbles are not easy to adsorb, the surface quality of a casting blank is improved, and meanwhile, F is hopefully not added or is less added^-、Na⁺And harmful ions are generated, so that the pollution to the environment is reduced.

Claims

1. A device for adding heated solid-state covering slag into a crystallizer in the continuous casting process comprises a continuous casting crystallizer and a crystallizer platform, and is characterized in that a trolley driving system is arranged on the right side of the continuous casting crystallizer, a covering slag heating system is arranged on the upper part of the trolley driving system,

2. The apparatus for feeding solid mold flux into a mold in a continuous casting process according to claim 1, wherein the mold flux heating rectangular unit is composed of a mold flux heating chamber, a stainless steel plate, an asbestos protecting layer, a heat-conductive copper plate and a heating element, the stainless steel plate and the asbestos protecting layer are disposed at an upper portion of the mold flux heating chamber, the heat-conductive copper plate and the heating element are disposed at a lower portion of the mold flux heating chamber, and a plurality of temperature thermocouples are symmetrically disposed at the upper portion and the lower portion of the mold flux heating chamber, respectively.

3. The apparatus for feeding heated solid mold flux to a mold in a continuous casting process according to claim 2, wherein the asbestos has a thickness S₁0.01-0.03 m, and its heat conductivity is lambda₁0.16-0.37W/m DEG C; the melting point of the stainless steel plate is 1300-1600 ℃, and the thickness S of the stainless steel plate is₂0.005-0.02 m, and a thermal conductivity lambda₂10-30W/m DEG C; the bottom area of the covering slag heating chamber is A, m²The thickness H is 0.1 m-0.5 m; the melting point T of the heat-conducting copper plate is 800-1100 ℃; the thermal conductivity of each of the above materials is a thermal conductivity at 300 ℃.

4. The apparatus for feeding heated solid mold flux to a mold in a continuous casting process according to claim 1, wherein the rectangular unit for mold flux heating has an inclination angle of β degrees, that is, an angle β degrees from a horizontal plane is 0 to 90 degrees.