KR101424497B1 - Method for manufacting tundish - Google Patents

Abstract

The present invention relates to a method of manufacturing a tundish capable of preventing a coating layer applied to a permanent field from falling off during the manufacture of a tundish, comprising the steps of: preparing a tundish having a tundish portion and a tundish portion; A step of constructing a stadium, a step of constructing a permanent field between a stadium ground and a permanent field former after inserting a permanent field former, a step of forming a clamp part in a side wall of the permanent field after completion of the permanent field formation, And forming a coating layer.

Description

{METHOD FOR MANUFACTING TUNDISH}

The present invention relates to a dry and non-aqueous tundish dish, and more particularly, to a tundish manufacturing method capable of preventing a coating layer applied to a permanent field from falling off during manufacturing of a tundish.

In general, a continuous casting machine is a facility for producing a slab of a predetermined size by receiving a molten steel produced in a steelmaking furnace and transferred to a ladle to a tundish and supplying it as a mold for a continuous casting machine.

The continuous casting machine includes: a ladle for storing molten steel; a continuous casting machine mold having a tundish and an initially cooled molten steel introduced from the tundish to form a casting having a predetermined shape; and a casting machine connected to the casting mold, And a plurality of pinch rollers for moving the pinch rollers.

Generally, a tundish is a container for storing molten steel discharged from a ladle in a continuous casting process before supplying it to a mold.

A related prior art is disclosed in Korean Patent Laid-Open Publication No. 10-2012-0001849 (public date: 2012.05.05 name: "tundish").

The present invention provides a method for manufacturing a tundish which can prevent a coating layer applied to a permanent field from falling off during tundish production, thereby preventing cracks from occurring in a permanent field and extending service life when using tundish.

The technical objects to be achieved by the present invention are not limited to the above-mentioned technical problems.

According to another aspect of the present invention, there is provided a method of manufacturing a tundish, comprising the steps of: preparing a tassel having a tumbling section and a tumbling section; constructing a tassel so as to contact the inner surface of the tassel; A step of constructing a permanent field between the quasi-spherical ball field and the permanent field formers, a step of forming a permanent part, a step of forming a clamp part in a side wall part of the permanent field, and a step of forming a coating layer by inserting a coating layer former.

Specifically, the clamp portion includes a plurality of first clamping grooves formed in a side wall portion adjacent to the bottom of the permanent field, and a plurality of second clamping grooves spaced apart from the upper portion of the first clamping groove, The second clamping grooves may be formed in a zigzag shape parallel to each other.

More specifically, the first clamping groove and the second clamping groove can be extended to a length of 10 to 30 mm with a depth of less than 2 mm.

More specifically, any one of the first and second clamping grooves and the adjacent first and second clamping grooves has a gap between the right and left sides of 10 mm to 15 mm, and the first and second clamping grooves have a length of 20 mm to 30 mm And can be spaced up and down.

As described above, the present invention has an advantage in that a clumping part is formed on the surface of the permanent field in manufacturing the tundish, and the coating layer is prevented from coming off due to the coating layer sticking to the former when the coating layer former is demolded .

1 is a schematic view of a continuous casting machine according to the present invention,
Fig. 2 is a view for explaining the continuous casting machine of Fig. 1 centering on the flow of molten steel, and Fig.
FIG. 3 is a view showing a process of manufacturing a tundish by the method of manufacturing a tundish according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the drawings, the same components are denoted by the same reference symbols whenever possible. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

FIG. 1 is a schematic view of a continuous casting machine according to the present invention. Continuous casting is a continuous casting process in which a molten metal is continuously cast in a mold without a bottom, ) Is a casting method to extract. Continuous casting is used to manufacture intermediate products such as slabs, blooms, and billets, which are mainly made of long products of simple cross-section such as square, rectangular, and circular, and rolling materials.

The shape of the continuous casting machine is classified into a vertical type, a vertical bending type, a vertical bending type, a curved type, and a horizontal type. In FIGS. 1 and 2, a curved continuous casting machine is shown.

1, a continuous casting machine includes a tundish 100, a mold 30, a secondary cooling bed 60, 65, a pinch roll 70, and a cutter 90.

A tundish 100 is a container for receiving molten metal from a ladle 10 and supplying molten metal to a mold 30. The ladles 10 are provided in a pair and alternately receive the molten steel M and supply the molten steel M to the tundish 100. In the tundish 100, the supply rate of the molten metal flowing into the mold 30 is controlled, the molten metal is distributed to each of the molds 30, the molten metal is stored, and the slag and the nonmetallic inclusions are separated.

The mold 30 is usually made of water-cooled copper and allows the molten steel M to be firstly cooled. The mold 30 has a pair of structurally opposed surfaces opened to form a hollow portion in which the molten steel M is accommodated. In the case of manufacturing a slab, the mold 30 includes a pair of barriers and a pair of end walls connecting the barriers. Here, the end wall has a smaller area than the barrier. The walls of the mold 30, mainly the end walls, can be rotated and moved away from each other to have a certain level of taper. This taper is set to compensate for the shrinkage due to the solidification of the molten steel M in the mold 30. The degree of solidification of the molten steel (M) varies depending on the carbon content, type of powder, casting speed, and the like depending on the steel type.

The mold 30 maintains the shape of the casting withdrawn from the mold 30 and forms a solidified shell or solidifying shell 81 (see FIG. 2), which is strong enough to prevent molten metal, And the like. The water-cooling structure includes a method of using a copper tube, a method of forming a water-cooled groove in a copper block, and a method of assembling a copper tube having a water-cooled groove.

The mold 30 is oscillated by the oscillator 40 to prevent the molten steel M from adhering to the wall surface of the mold 30. [ A lubricant is used to reduce the friction between the casting mold 30 and the casting during oscillation and to prevent burning. As the lubricant, powder added to the molten metal surface in the mold 30 is used. The powder is added to the molten metal in the mold 30 to become slag, and the lubrication of the mold 30 and the casting, as well as the oxidation and nitrification of the molten metal in the mold 30 and keeping warmth, It also performs the function of absorption. A powder feeder 50 is installed to feed the powder into the mold 30. The portion of the powder feeder 50 that discharges the powder is directed to the inlet of the mold 30.

The secondary cooling bases 60 and 65 further cool the molten steel M primarily cooled in the mold 30. The molten primary molten steel M is cooled directly by the spray 65 spraying water, while being maintained by the support roll 60 so that the coagulation angle is not deformed. Most of the casting is carried out by the secondary cooling bases (60, 65).

The pinch roll 70 is a drawing device and employs a multi-drive type or the like in which a plurality of pinch rolls 70 are used so that the casting can be pulled out without slipping. The pinch roll 70 pulls the solidified leading end portion of the molten steel M in the casting direction so that the molten steel M passing through the mold 30 can be continuously moved in the casting direction.

The cutter 90 is formed so as to cut the continuously produced casting into a predetermined size. As the cutter 90, a gas torch or an oil pressure shearing machine may be employed.

Hereinafter, the continuous casting machine of FIG. 1 will be described, focusing on the flow of molten steel M. FIG.

Referring to FIG. 2, molten steel M flows into tundish 100 while being accommodated in ladle 10. For this flow, the ladle 10 is provided with a shroud nozzle 15 which extends toward the tundish 100. The shroud nozzle 15 is extended to be immersed in the molten steel M in the tundish 100 so that the molten steel M is not exposed to the air and oxidized and nitrided. The case where the molten steel M is exposed to air due to breakage of the shroud nozzle 15 or the like is referred to as open casting.

The molten steel M in the tundish 100 is caused to flow into the mold 30 by the submerged entry nozzle 25 extending into the mold 30. The immersion nozzle 25 is disposed at the center of the mold 30 so that the flow of the molten steel M discharged from both the discharge ports of the immersion nozzle 25 can be made symmetrical. The start, discharge speed and interruption of the discharge of the molten steel M through the immersion nozzle 25 are determined by a stopper 21 provided on the tundish 100 corresponding to the immersion nozzle 25. [ Specifically, the stopper 21 is vertically movable along the same line as the immersion nozzle 25 so as to open and close the inlet of the immersion nozzle 25. The control of the flow of the molten steel (M) through the immersion nozzle (25) can use a slide gate method different from the stopper method. The slide gate controls the discharge flow rate of the molten steel M through the immersion nozzle 25 while the plate material slides horizontally in the tundish 100. [

Molten steel (M) in the mold (30) starts to solidify from a portion in contact with the wall surface of the mold (30). This is because the periphery of the molten steel M is liable to lose heat by the water-cooling mold 30. The rear portion along the casting direction of the strands 80 is wrapped by the solidified shell 81 in which the non-solidified molten steel M is solidified by the method in which the peripheral portion first solidifies.

The non-solidified molten steel M is moved in the casting direction together with the solidifying shell 81 as the pinch roll 70 (see FIG. 1) pulls the tip end portion 83 of the fully solidified strand 80. The non-solidified molten steel (M) is cooled by the spray (65) spraying the cooling water in the above-mentioned moving process. This causes the thickness of the uncooled steel (M) to gradually decrease in the strand (80). When the strand 80 reaches one point 85, the strand 80 is filled with the solidified shell 81 in its entire thickness. The solidified strand 80 is cut to a predetermined size at the cutting point 91 and is divided into semi-finished products P such as slabs, blooms, billets, and the like.

The tundish 100 is formed in a box shape having an open top so as to contain the molten steel M and includes a container 110 having an outer shape of the tundish 100, A permanent field 130 formed on the inner surface of the quasi-spherical ball 120, and an inner surface of the inner surface of the permanent field 130. The inner surface of the inner surface of the permanent surface 130 is formed with a predetermined thickness using a plurality of bricks, And a coating layer 140 applied to the substrate.

In the conventional tundish 100, when the tundish 100 permanent structure 130 is newly installed, the surface of the tundish 100 is smooth, so that the coating layer 140 is formed and then the coating layer former 142 is removed from the coating layer former 142, The coating layer 140 adheres to the coating layer 140, and the coating layer 140 is intermittently peeled off from the permanent coating 130.

Accordingly, it is an object of the present invention to provide a method of manufacturing a tundish which prevents the coating layer 140 from falling off by increasing the bonding force between the permanent sheet 130 and the coating layer 140 when the tundish 100 is manufactured.

FIG. 3 is a view showing a manufacturing procedure of the tundish 100 according to the present invention. In order to manufacture the tundish 100 according to the present invention, first, a scallop 110 is manufactured (step S1).

The screed 110 forms the overall shape of the tundish 100. The screed 110 is composed of a molten metal portion 112 and a molten metal portion 114 as shown in the drawing. The molten steel M is guided by the molten steel M from the ladle 10 to guide the molten steel M toward the molten steel M as the molten steel M is guided from the molten steel M) to guide the molten steel (M) to the mold (30).

After the production of the crust 110 is completed (step S1), the crust 110 is built in the crust 110 (step S2).

When the permanent field 130 described below is damaged due to an accident or other factors, the quasi-ball pitcher 120 prevents the leakage of the molten steel M and prevents the leakage of the quasi-ball ball through the hole in the ball 110, And is applied so as to abut the inner surface of the iron foil 110. [ The quasi-spherical ball 120 thus constructed is made of a material having excellent heat resistance, that is, a refractory capable of withstanding high temperatures so as to be able to be operated several times even if the permanent field 130 is lost.

Thus, when the manufacture of the quasi-spherical ball 120 is completed (step S2), the permanent field 130 is formed (step S3).

The permanent field 130 is formed inside the quasi-ball stadium 120 as shown. In order to construct the permanent field 130, the permanent filament former 132 is inserted between the permanent filament 120 and the permanent filament inlet 120 between the permanent filament former 132 and the semi-permanent ball ground 120 And the permanent field 130 is constructed. At this time, the inflow material for permanent use was mixed with 60% alumina, 30% Sio2, 3% CaO, and other impurities in the form of powder. After stirring with water, the mixture was placed between permanent Changmoeformer (132) do. After completion of the construction of the permanent field 130, the permanent field former 132 is demoulded to complete the permanent field.

The thus constructed permanent field 130 protects the quasi-spherical ball 120 and is preferably made of a material excellent in erosion resistance and abrasion resistance so as to withstand the high temperature molten steel M because the molten steel M is contacted. In FIG. 3 (S3), the permanent sheet formers 132 are shown to be deformed after the permanent sheet 130 is constructed.

As described above, when the permanent field 130 is completed (S3), the clamping portion 134 is formed in the permanent field 130 so that the coating layer 140 is not detached at the time of the coating layer S5 to be described later S4).

The clamp unit 134 in step S4 includes a plurality of first clamping grooves 136 formed on the side wall adjacent to the bottom of the permanent field 130 and a plurality of second clamping grooves 136 spaced apart from the top of the first clamping grooves 136 And a plurality of second clamping grooves 138 formed therein. At this time, the first clamping groove 136 and the second clamping groove 138 are formed in a zigzag shape parallel to each other.

On the other hand, the first clamping groove 136 and the second clamping groove 138 extend to a length (L2) of 10 to 30 mm with a depth (L1) of less than 2 mm.

The first and second clamping grooves 136 and 138 adjacent to the first and second clamping grooves 136 and 138 have a gap of 10 mm to 15 mm. The first clamping groove 136 and the second clamping groove 138 have an interval L3 between 20 and 30 mm.

If the depth of the first clamping groove 136 and the second clamping groove 138 is 2 mm or more, the first clamping groove 136 and the second clamping groove 138 may be damaged, Is preferably formed to a depth of less than 2 mm.

If the lengths of the first and second clamping grooves 136 and 138 are greater than 30 mm, an excessive permanent field 130 loss results in a high rate of cracking during operation and the length of the first and second clamping grooves 136 and 138 The coating layer 140 adheres to the coating layer former 142 at the time of demoulding the coater layer former 142 to be described later, so that the coating layer 140 may be dropped. The coating strength of the coating layer 140 deteriorates.

If the gap between any one of the adjacent first and second clamping grooves 136 and 138 and the width of the other first and second clamping grooves 136 and 138 is less than 10 mm, the permanent field 130 is lost, If the gap between any one of the first and second clamping grooves 136 and 138 and the other first and second clamping grooves 136 and 138 is greater than 15 mm, any one of the first and second clamping grooves 136 and 138, Adhesion of the coating layer 140 between the grooves 136 and 138 and the adjacent first and second clamping grooves 136 and 138 is reduced.

Similarly, when the distance between the upper and lower sides of the first clamping groove 136 and the second clamping groove 138 is less than 20 mm, the permanent field 130 is lost. When the distance between the upper and lower sides exceeds 30 mm, 136 and the second clamping groove 138 of the coating layer 140 is lowered.

When the manufacturing of the clamping part 134 is completed (step S4), the coating layer 140 is formed next (step S5). In order to form the coating layer 140, a coating layer former 142 is inserted between the permanent layers 130 and then a powder coating material is inserted between the coating layer former 142 and the permanent layer 130, Heat is applied for 1 hour or more, and after completion of the formation of the coating layer 140, the coating layer former 142 is demolded. At this time, even if the coating layer former 142 is demolded, the coating layer 140 is fixed by the clamping portion 134, so that the coating layer 140 is not dropped on the surface of the permanent sheet 130. In FIG. 3 (S5), the coating layer former 142 is removed after the coating layer 140 is formed.

The coating layer 140 may be formed on the surface contacting the molten steel M for protecting the quasi-spherical ball 120 and the permanent field 130 and extending the service life of the molten steel. Also, the coating layer 140 is preferably made of a material that can withstand high temperatures, and is made of magnesia and alumina.

The clamping portion 134 is formed on the surface of the permanent sheet 130 in manufacturing the tundish 100 so that the coating layer 140 is formed on the coating layer former 142 even if the coating layer former 142 is demolded after the coating layer 140 is formed. It is possible to prevent the coating layer 140 from falling off.

By preventing the coating layer 140 from falling off, it is possible to prevent the permanent sheet 130 from cracking when the tundish 100 is used, thereby prolonging the service life of the tundish 100, It is possible to prevent the permanent field 130 from collapsing during the deformation and deformation of the damper 130.

The method of manufacturing a tundish as described above is not limited to the configuration and operation of the embodiments described above. The embodiments may be configured so that all or some of the embodiments may be selectively combined so that various modifications may be made.

100: tundish 110: evil
120: Jeong Young Park 130: Permanent Park
132: Permanent sheet former 134: Clamp section
136: first clamping groove 138: second clamping groove
140: coating layer 142: coating layer former

Claims (4)

A step of fabricating a screed having a molten metal portion and a molten metal portion;
Forming a stamina so as to abut the inner surface of the iron body;
A step of inserting a permanent sheet former between the semi-permanent ball lands, and then injecting an inflow material between the semi-permanent ball ground and the permanent sheet formers to construct a permanent sheet;
Forming a clamping portion on a side wall of the permanent field after the completion of the permanent strengthening step; And
And forming a coating layer by inserting a coating layer former between the permanent fields after forming the clamp portion,
The clamp unit includes:
A plurality of first clamping grooves formed in side wall portions adjacent to the bottom of the permanent field and a plurality of second clamping grooves spaced apart from the upper portion of the first clamping grooves,
The first clamping groove and the second clamping groove are parallel to each other and formed in a zigzag shape,
Any one of the first and second clamping grooves and the neighboring first and second clamping grooves has a gap of 10 mm to 15 mm,
The first clamping groove and the second clamping groove have an interval between the upper and lower sides of 20 mm to 30 mm,
Wherein the step of constructing the permanent field comprises the steps of inserting a permanent field former between the semi-permanent ball fields and then injecting a permanent field inflow material between the permanent field former and the semi-permanent ball field to construct a permanent field, Powder composed of 60% alumina, 30% SiO2, 3% CaO, and other impurities was stirred with water, put into the space between the permanent sheet formers and the quasi-spheroidal soil, cured for 48 hours, and then the permanent sheet was built And removing the permanent sheet former to complete the permanent sheet forming tank.
delete The method according to claim 1,
Wherein the first clamping grooves and the second clamping grooves have a depth of less than 2 mm and extend to a length of 10 to 30 mm.


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