KR19990015969A - Coated lead for prevention of back oxidation and its manufacturing method and usage - Google Patents

Abstract

The present invention is to prevent the back oxidation of lead by preventing the contact of impression graphite [C] contained in the lead and oxygen by coating the back of the lead used as a refractory forming a ladle that is a container containing the molten metal during the steelmaking process. The present invention relates to a backside anti-oxidation coated lead which maintains the strength of the lead and prolongs its service life, and a method of manufacturing and using the same.

The composition is based on impression graphite [C] containing fluorinated lead by weight ratio of 60% or more of SiO _{2 to} 15% or less of Na ₂ O, 10% or less of B ₂ O _3, 10% or less of Z _n O, 7% or less of CaO, and Al ₂ O. A method of coating a portion of the lead with a molten liquid by heating the glass containing the composition of ₃ % or less to 900 ° C. to 1300 ° C. and depositing it in the molten melt; It is about how to use and when.

Description

Coated lead for prevention of back oxidation and its manufacturing method and usage

The present invention relates to a coating lead for prevention of back oxidation, and a method for manufacturing the same and a method for using the same, wherein the back surface of the lead used as a refractory forming a rod, which is a container for holding molten metal, is contained in the lead. The present invention relates to a coating lead for preventing back oxidation, and a method of manufacturing the same and a method of using the same to prevent contact between carbon and oxygen to prevent back oxidation.

In general, in the steelmaking and smelting process, a refractory resistant at high temperatures is essentially used as a result of high-temperature refining process, and the construction method is a permanent elongation (20) on the inner side of the ladle required for refining as shown in FIG. ) And semi-permanent yeon yeon (30) and built-in yeon (100) and built yeon (100) is a place that is actually in contact with the hot molten slag line (Slag Line), wall for the yeon and It is divided into floor lead. The slag area 200 in which slag is concentrated is used as a lead having a property of excellent corrosion resistance in molten steel and slag, and a representative lead is a fluorine-based MgO-C lead having MgO and impression graphite as the main raw material ( The following is used as the carbon carbon, because the satisfactory corrosion resistance and spalling resistance to molten steel and slag at the same time.

However, the impression graphite [C] constituting the mag carbon lead has a problem of weakening the lead by lowering the physical properties of the mag carbon lead by reacting with oxygen in the air to generate [C] vaporization. In particular, hot molten metal heats the air so that oxygen in the air oxidizes the drawn graphite as in the following reaction formula, thereby rapidly lowering the physical properties of the lead.

C + 1 / 2O ₂ = C- (1)

CO + 1 / 2O ₂ = CO _2- (2)

CO ₂ + C = 2CO- (3)

C + O ₂ = CO _2- (4)

In addition, oxides of Fe, Mn, and Cr contained in the slag, such as C + [Fe, Cr, Mn] O ₂ = [Fe, Cr, Mn] + CO- (5), are reacted with the impression graphite [C] to raise them. There was a problem of promoting the vaporization of graphite to make the soft brittle. Therefore, by suppressing the above reaction to prevent oxidation of [C], by adding metal powders such as Al, Si, etc., which are reacted with oxygen before [C] to softening, Al, Si, etc. react with oxygen [ Although the method of preventing oxidation of C] is used, there are some effects but it does not completely suppress the reaction.

In addition, the reaction takes place more actively on the back surface 130 than on the surface of the pontoon because the slag is attached to the surface of the pontoon to form a coating layer on the surface of the pontoon to block the contact with oxygen, whereas on the back part, the mortar and duct Air is introduced into the gap between them, and the high temperature of the molten metal causes the atmosphere to easily occur in the reaction. Therefore, the rear oxidation also progresses in proportion to the increase in the number of times of use of the ladle, and the ladle becomes vulnerable, and the portion where the oxidation of [C] is increased is lost. There was a problem that caused the accident of collapse of the melt due to the collapse of the tilting of the impact or the erosion of the melt, increasing the repair cost and frequent safety work due to frequent repairs.

Therefore, the technical problem to be achieved by the present invention is to prevent the contact between the tough graphite graphite [C] constituting the lead and oxygen in the air even when the air flows into the rear part of the lead to solve the above problems, the back oxidation of the lead To provide a lead and a method of manufacturing and using the same.

1 is a cast ladle refractory construction cross-sectional view.

Figure 2 is a cross-sectional view showing the rear oxidation process of the conventional [C] containing fluorine lead.

Figure 2 is a cross-sectional view showing a back oxidation process with a back oxidation coating lead provided with the present invention.

Figure 3 is a plan view of the back anti-oxidation coated lead provided with the present invention.

Figure 3 is a cross-sectional view of the back anti-oxidation coating edge provided with the present invention.

4 is a perspective view of a kite used in the thin embodiment;

4 is a perspective view showing a test method.

* Description of the symbols for the main parts of the drawings *

10: back side anti-oxidation coating and 11-1: length direction coating layer

11-2: Thickness coating layer 12: Melting contact surface

20: Yeonwa, permanent director 30: Yeonwa, permanent director

40: Maltar 50: Experimental

51: insulation

The composition for achieving the technical problem to be achieved by the invention is composed of 80% to 95% MgO, 5% to 20% graphite graphite, 2% to 8% metal antioxidant, 2% to 5% binder, crushed, classified Fluoride lead containing graphite phosphate [C] produced by drying, storage, basis weight, kneading, molding, drying, inspection, and drying after drying for 6 hours at 400 ℃ or below. 900 ° C to 1300 ° C for glass having 60% or more of SiO ₂ , 15% or less of Na ₂ O, 10% or less of B ₂ O _3, 10% or less of ZnO, 7% or less of CaO, and 7% or less of Al ₂ O _{3 by} weight between steps. A process for producing anti-backside coated lead and a process for forming the anti-oxidation of the backside graphite, comprising: immersing and coating impression graphite [C] -containing fluorine lead on the molten glass, followed by drying. ₂ components by weight ratio of SiO ₂ 60% or more, Na ₂ O 15% or less, B ₂ O ₃ 10% or less, ZnO 10% or less, C The backside anti-oxidation coating lead coated with a part of the lead with a molten liquid by heating the glass having aO 7% or less and Al ₂ O ₃ 7% or less by heating it at 900 ° C to 1300 ° C, In case of construction using, the parts where the coated parts are in contact with each other are composed of a back anti-oxidation coating lead which is constructed without using mortar and usage.

It will be described in detail as follows.

MgO by weight, 80 ~ 95% by weight, 5 ~ 20% by impression graphite [C], 2 ~ 8% by metal antioxidant, 2 ~ 5% by binder, grinding, classification, storage, basis weight, kneading, forming, drying, In the manufacturing method of impression graphite [C] -containing fluorinated lead (100) manufactured by drying after drying for 6 hours at 400 ° C. or lower after molding, SiO ₂ 60% by weight ratio between the drying process and the inspection process. Above, Na ₂ O 15% or less, B ₂ O ₃ 10% or less, ZnO 10% or less, CaO 7% or less, Al ₂ O ₃ 7% or less, the temperature of the glass is heated to 900 ℃ to 1300 ℃ and melted The graphite phosphate [C] -containing fluorinated lead 100 was deposited on the glass in a length direction of about 1/58 so that the lengthwise coating layer 11-1 of the lead was 3 mm or less and the thickness coating layer 11-2 was 1.5 mm or less. Backside anti-oxidation coating lead and manufacturing method consisting of the coating process, the anti-backside anti-oxidation coating lead 10 produced by the manufacturing method and the anti-back burn In case of construction using the coated lead 10, the parts where the coated parts are in contact with each other do not use the mortar 40, and thus the back oxidation preventive coated lead which prevents air from entering the molten contact surface 12 from the back 13 It consists of usage.

The description of the operation is as follows.

In the case of using the rear surface anti-oxidation coating yeonwa equipped with the present invention as shown in FIG. Part of the upper and lower ends of the lead is in contact with the glass layer 11 to prevent the introduction of air to fundamentally prevent the condition of the rear oxidation. Therefore, the oxidation of [C] does not occur and the coated glass starts melting at around 900 ° C. to increase the adhesive force between the lead 10 and the lead 10 to prevent dropping of the lead 10. In addition, regarding the length and thickness of coating the lead, coating one fifth of the length of the lead with molten glass is to prevent the coated glass from contacting the molten glass. This is because it is more vulnerable than maltar or yeonwa, so the intrusion of molten metal occurs easily.

The thickness of the lead and the thickness coating layer 11-2 is 1.5 mm or less. The thickness of the lead and the thickness coating layer 11-1 is 3 mm or less. This is because there is a difficulty in forming the horizontal, and if the thickness of the lead and the longitudinal coating layer is more than 3mm, some of the glass may melt or react with the mortar during use. In addition, the coating melt is not limited to the above-described glass, and may be used as long as it is a substance that forms a liquid phase in the range of 700 ° C to 1300 ° C.

In order to verify the above-described operation of the present invention, the following implementation was carried out.

EXAMPLE

As shown in FIG. 4, a back anti-oxidation coated lead 10 provided with the present invention was prepared in a lead having the same material and size as the conventional [C] -containing fluorine lead 100 made of a width of 230 mm, a width of 150 mm, and a height of 80 mm. After inserting the 170 mm into two experimental furnaces 50 heated at 1600 ° C. as shown in FIG. 4, the work was repeated five times for 1 minute after cooling for 20 minutes in the atmosphere. At this time, the experiment furnace 50 prevented the outflow of heat by using the heat insulator 51, and after cutting five times each edge is cut 50mm from the back as shown in Figure 4 to compare the strength and weight of the lead A comparison table was prepared as follows.

Comparative Table 1 is a weight comparison table showing the weight of the conventional kite when the weight of the kite equipped with the present invention is 100, it can be seen that the weight of 3 to 5% is reduced, which is [C] by 3 to 5% by weight It is oxidized and vaporized.

[Comparison Table 1]

Comparative Table 2 is a strength comparison table, which shows that the strength of the kite provided with the present invention is 100, indicating that the strength of the kite is 20% or more, and the density of the kite is inhibited by the oxidation of [C]. will be.

[Comparison Table 2]

Therefore, it can be seen that the oxidation resistance of [C] is prevented from maintaining the good strength of the coated lead for back oxidation prevention provided with the present invention.

In the effect of the present invention, even when air flows into the rear surface of the lead, the tough graphite [C] constituting the lead prevents contact with oxygen in the air to prevent back oxidation of the lead, thereby extending the life of the lead and melting It prevents leakage accidents and contributes to safety work as well as productivity.

Claims (7)

MgO is composed of 80 ~ 95% by weight, 5 ~ 20% of impression graphite [C], 2 ~ 8% of metal antioxidant, and 2 ~ 5% of binder, and crushed, classified, stored, basis weight, kneaded, molded, dried, inspected In the manufacturing process with fluorinated graphite containing impression graphite [C], which is manufactured through a drying process and dried at a temperature of 400 ° C. or lower after molding, SiO ₂ 60% or less, Na ₂ O in a weight ratio between the drying process and the inspection process. 15% or less, B ₂ O ₃ 10% or less, ZnO 10% or less, CaO 7% or less, Al ₂ O ₃ 7% or less The glass containing the composition is heated to a temperature of 900 ℃ to 1300 ℃ and molten glass A method of producing a coated lead for back oxidation prevention, characterized in that the graphite phosphate [C] -containing fluorine lead is deposited. The method according to claim 1, wherein a substance which is dissolved in the range of 700 ° C to 1300 ° C is used as a glass substitute. Impression graphite [C] containing fluorinated lead in weight ratio of 60% or less of SiO ₂ , 15% or less of Na ₂ O, 10% or less of B ₂ O _3, 10% or less of ZnO, 7% or less of CaO, 7% or less of Al ₂ O ₃ The glass containing the composition was heated to 900 ℃ ~ 1300 ℃ and immersed in the molten molten liquid to coat a portion of the lead with a molten liquid, characterized in that the coating lead to prevent oxidation. The coated lead of claim 3, wherein the coated length of the kite is 1/5 of the total length in one side of the length of the kite. The coating layer thickness of claim 3, wherein the coating layer thickness of the lead is 1.5 mm or less in the lead thickness direction and 3 mm or less in the lead length direction. The method according to claim 3, wherein a substance which is melted in the range of 700 ° C to 1300 ° C is used as a glass substitute. The area where the coated parts are in contact with each other when constructing the coated lead is a method of using the coated lead for back oxidation prevention, characterized in that it is constructed without using maltar.