JPS59159253A - Belt type continuous casting machine - Google Patents

Abstract

PURPOSE:To permit easy operation and to increase a casting speed by supporting belts by means of plural continuously provided hydrostatic bearings, and disposing plural rollers spaced from each other in the hydrostatic bearing parts. CONSTITUTION:A belt type continuous casting machine casts and takes out continuously a billet 66 by moving belts 35, 36 constituting the shell on the opposed long sides of a rectangular casting mold at approximately the same speed as the billet 66 to be formed. The belt 35 is supported by plural hydrostatic bearings 38-44, and the belt 36 by plural hydrostatic bearings 45-51. Plural rollers 53 spaced from each other are disposed in the hydrostatic bearing parts. The movement of the belts 35, 36 is assisted by driving the rollers 53 to decrease the tensile force acting on the belts 35, 36 and therefore the hydrostatic bearing parts are made longer without possibility of the rupture in the belts. The continuous casting at the higher speed is thus made possible.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a belt-type continuous casting machine for producing slab materials, and particularly relates to a structure for supporting the belt of a continuous casting machine. A continuous casting machine that manufactures slab material (slab material) for intermediate strip material is comprised of a rectangular mold and a roller guide connected to the rectangular mold.

However, in the conventional method, a slab with a thin solidified shell formed in a mold is slidably pulled out from the mold by a guide roller at the bottom of the mold, which tends to break the solidified shell, making it difficult to speed up casting. It was difficult.

Therefore, we used belts on the opposing long sides of the rectangular mold,
A synchronous continuous casting machine has been developed in which continuously cast slabs are taken out by moving a thin solidified shell formed in a mold and the belt almost in synchronization. In this method, the solidified shell and belt move almost synchronously, making it possible to achieve a continuous casting speed several times higher than that of the conventional continuous casting machine mentioned above. Moreover, this belt-type continuous casting machine is not only effective in stably forming the initially solidified shell, but also has an advantageous structure in terms of supporting the static pressure load of molten steel.

In other words, in a belt-type continuous casting machine, a planar hydrostatic pressure bearing is placed on the back of the belt, which not only cools the slab, but also prevents solidification shells between the rollers when the slab is guided and supported by conventional rollers. Since it is possible to prevent the phenomenon of bulging caused by the static pressure of molten steel, that is, bulging deformation, it is now possible to obtain products of extremely high quality.

On the other hand, when trying to further increase the speed of this belt-type continuous casting machine to improve productivity, the problem is that the time it takes for the poured molten metal to solidify to the center of the slab increases in proportion to the speed. occurs. For example, thickness 90+++m x width 1
000m at the conventional continuous casting speed (2m/min)
When casting at 10 m 7 m1n, which is about 5 times the
It takes 3 minutes to completely solidify the inside of the slab, and the length of the continuous casting machine used for this is 30 m, which is quite long. Therefore,
This section of the belt-type continuous preparation machine must be supported by the hydrostatic bearing described above, but even this hydrostatic bearing has an average coefficient of friction of 0.03, so if the molten steel static pressure is applied to the belt, The existence of this coefficient of friction creates a large resistance to belt movement when taking the slab out to the outside. Furthermore, since the hydrostatic bearings of conventional belt-type continuous casting machines cannot apply driving force to the belt, the belt must be driven externally. However, if the belt driving force becomes excessive in this way, there is an increased risk of the belt being pulled and broken, which is disadvantageous. As a result, there is a natural limit to the length of the section on which the static pressure of molten steel acts, and therefore there is a limit to how high the speed can be increased even in a belt-type continuous casting machine. At best, it was possible to obtain a casting speed of about Furthermore, it is difficult to manufacture a long, integrated hydrostatic bearing, so in such cases, it is constructed by connecting the divided parts, but there is a step at the connecting part of the divided hydrostatic bearings. Another drawback was that it required a great deal of effort to correct this difference in the actual machine.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a belt-type continuous casting machine that eliminates the above-mentioned drawbacks, is easy to operate, and can increase casting speed.

[Summary of the invention]

The present invention consists of a belt on the opposite long side outer shell of a rectangular mold, and a belt that continuously takes out slabs by moving this belt almost synchronously with the slabs formed in the mold. In a type continuous casting machine, the static pressure of molten steel applied to the belt is supported by a plurality of divided planar hydrostatic pressure bearings connected together, and the hydrostatic pressure bearing section is provided with a plurality of spaced apart hydrostatic pressure bearings. The above object is achieved by arranging rollers and driving at least one of these rollers to assist the movement of the belt.

Next, the principle of the present invention will be explained. In a conventional continuous casting machine, the static pressure of molten steel is supported by guide rollers 1 as shown in FIG. However, the inside of the slab 2 is in an unsolidified state, and the static pressure inside causes the outer solidified shells 3 and 4 to undergo bulging deformation between guides o and 21 as shown in the figure, which causes cracks inside the slab. This caused the quality of the slab to deteriorate.

Since this bulging deformation δ occurs in proportion to the fourth power of the roller pitch, it is important to reduce the pitch of the row 21 as much as possible.
ing. However, since the slab is cooled by a spray header placed in the roller gap, the roller gap needs to be a distance of 40 to 50 mm, and if the roller diameter is made smaller in order to shorten the roller pitch, the roller There is a limit to reducing the diameter of the roller due to the bending, and therefore there is a limit to improving the quality of slabs due to bulging deformation.

On the other hand, the hydrostatic ball bearings 5, 6, 7.8 shown in FIG. 2 support the solidified shell 3 of the slab 2 in a planar manner via a belt 9.10. In addition, the hydrostatic pressure bearing 5 is connected to the high pressure water supply hole 11.
High-pressure cooling water is injected onto the surface of the belt 9 and flows in the direction of the arrow to create a gap of 5 to 100 μm between the belt 9 and the bearing surface, supporting the static pressure of the unsolidified portion of the slab 2 and supporting the static pressure of the unsolidified portion of the slab. Perform cooling.

In this way, in the belt-type continuous casting machine shown in FIG. 2, the slab 2 is supported by the continuous bells 9 and 10, so that the bulging deformation that occurs in the continuous casting machine shown in FIG. 1 does not occur. Moreover, since there is a gap between the belt 9.10 and the hydrostatic bearing surface, the fixed hydrostatic bearings 5 to 8 have a gap between [-, bell) 9.1
Even if the slab 2 is moved, the resistance due to the static pressure of the molten steel can be made extremely small. However, this resistance is not zero, and as described above, as the section receiving molten steel static pressure becomes longer, the resistance increases in proportion to this.

Therefore, in the present invention, in order to reduce this increase in resistance, as shown in FIG.
By driving these rollers 12 and 13, a driving force is applied to the belts 9 and 10, and the resistance applied to the belt 9 is reduced. Moreover, this structure in which the rollers are disposed on the hydrostatic bearing section is different from the arrangement of the rollers 1 shown in FIG. The unsupported part of molten steel static pressure is less than 1/2 compared to that in Figure 19, and since bulging deformation is proportional to the fourth power of the unsupported part as mentioned above, the roller arrangement shown in Figure 2 is In this case, the bulging deformation rate is 1/16 compared to that shown in FIG. 1, and there is almost no deterioration in the quality of the slab 2. Therefore, in the present invention, the hydrostatic pressure bearing portion can be made as long as necessary in proportion to the casting speed, so that the casting speed can be increased. or,
The connection of each hydrostatic bearing is as shown in the figure: roller 12 and roller 1.
3 is provided at the joint between the hydrostatic pressure bearings 5 and 6 and the joint between the hydrostatic pressure bearings 7 and 8, so even if there is a slight difference in level between the hydrostatic pressure bearings, this molten steel static pressure can be absorbed in the unsupported part. This makes it easy to set up the mold.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 3 is a configuration diagram showing an embodiment of the belt type continuous casting machine of the present invention. The molten metal 32 of the tundish 31 is poured from the nozzle 33 into the belt mold 34.As shown in detail in FIG. 4, which is a sectional view taken along the line ■-■ in FIG. (bell) 35, 36 and a short side 37. Bell) 35.36 is supported by hydrostatic bearings 38°45. That is, cooling water is ejected from the supply hole 52 between the belt and the hydrostatic bearing surface, cools the molten steel and generates fluid resistance pressure to support the static pressure of the molten steel.

Returning to Fig. 3, the hydrostatic pressure bearing section has the hydrostatic pressure bearing 3 at the top.
8 to 44 are arranged, and hydrostatic pressure bearings 45 to 51 are arranged at the bottom. Moreover, a roller 53 is disposed between each connection of these hydrostatic pressure bearing parts. This roller 53 is supported by a bearing 54, as shown in FIG.
Driven by.

The above plurality of hydrostatic bearings are mounted on the upper support frame 59.6.
0.61 and 63.64, and is installed on a pedestal 65. The belt 35 is pressed against the upper surface of the slab 66 through the fluid pressure of the hydrostatic bearing.
Kite roller 67 and drive guide rollers 68, 69.7
0, the slab 66 is driven by 1 in the advancing direction. The belt 36 is also driven by guide rollers 71, 72 and driving guide rollers 73, 74, 75.

In a continuous casting machine with such a configuration, when producing a slab with a thickness of 90 m + n at a high speed of 10 yn/mm as described above, the time it takes to completely solidify the inside of the slab is approximately It takes 3 minutes, so the section supporting the molten steel needs to be 3 ohm. Since the average static pressure of molten steel is usually about 4 K7/crl, the load P applied to the entire length of the hydrostatic bearing is equal to the slab width 1
per m, 4 Kr/ix 30 mX177Z2=1
It will be 200t. Therefore, the friction coefficient of a hydrostatic bearing is 0.
03, the tensile force exerted by the drive guide roller on the belt must be 36. Dad, the thickness of the belt is 1.2.
Since the belt is selected to have a diameter of about 1.5 mm, the tensile force applied to the belt is as high as 30 Kg/++ m2, and as mentioned above, in this type of continuous casting machine where conventional rollers are not installed, the problem of belt breakage occurs. This is the name of the author.

Therefore, as shown in FIG. 3, a roller 53 is provided in the hydrostatic bearing section of this embodiment, and this is driven as shown in FIG. 5 to reduce the tensile resistance of the belt 35, 36. . This roller 53 is selected to have a diameter of approximately φ200 (ff), and is designed to support the static pressure of the molten steel between the roller portions.

Therefore, the average static pressure P of molten steel applied to one roller is 4Kflcrd x 1yn x 0.2m - 8t per 1m width of slab.
becomes. Further, since the coefficient of friction between the belt 35, 36 and the roller 53 is about 0.15, the force for driving the belt by one roller is 1.21. Therefore, in this embodiment, by installing a large number of rollers 53 as described above,
The problem of belt breakage is solved by reducing the pulling force exerted on the belt by the drive guide roller. Furthermore, as shown in Fig. 3, since the rollers 53 are arranged at the ends of each hydrostatic bearing, it is possible to alleviate the effect of the difference in level that occurs at the connection part of each hydrostatic bearing. This makes it easy to set up and arrange parts.

Note that if the rollers 53 are arranged continuously as shown in FIG. 1, bulging deformation of the molten steel will occur, so hydrostatic pressure bearings are arranged between the rows 253 as shown in FIG. It is set up discontinuously. Further, the roller 53 can be provided not at the end of the hydrostatic bearing but at the center.

Furthermore, in the bending type continuous casting machine as in the above embodiment, since a bending reaction force is generated in the part where the slab 66 is bent, the roller 53 is provided in the part where this reaction force is concentrated, and the belt 35.
It is also possible to further reduce the resistance applied to 6.

According to this example, the belt 35.36 is supported by a plurality of hydrostatic pressure bearings 38 to 51, and a roller 53 is disposed at each hydrostatic pressure bearing portion, and this row 253 is driven to rotate the belt 35.
．． By assisting the movement of belt 35.3
6, the hydrostatic bearing can be lengthened without fear of belt breakage. Therefore, it has the effect of increasing the casting speed of the belt-type continuous casting machine, and has the effect of significantly increasing productivity. In addition, a roller 53 is arranged at the end of the hydrostatic pressure bearing, and even if there is a slight difference in the connection part of the hydrostatic pressure bearing, the static pressure of the molten steel can be absorbed.
This has the effect of simplifying the setting of the belt mold 34 and facilitating the operation of the continuous casting machine.

〔Effect of the invention〕

As described above, according to the belt-type continuous casting machine of the present invention, the belt constituting the mold is supported by a number of connected hydrostatic bearings, and a plurality of rollers are arranged at intervals in the hydrostatic bearing part. By reducing the tensile force applied to the belt, it is possible to make the ram operation easier and speed up casting.

[Brief explanation of drawings]

Fig. 1 is a schematic configuration diagram showing an example of a conventional continuous casting machine, Fig. 2 is a partial sectional view of a belt type continuous casting machine showing the principle of the present invention, and Fig. 3 is a belt type continuous casting machine of the present invention. FIG. 4 is a cross-sectional view of IV-IV in FIG. 3,
FIG. 5 is a detailed configuration diagram of the roller 53 shown in FIG. 1.

Claims (1)

[Claims] 1. Continuously casting slabs by moving belts forming outer shells on opposite long sides of a rectangular mold at substantially the same speed as the slabs to be formed. A belt-type continuous casting machine for taking out the product, characterized in that the belt is supported by a plurality of connected hydrostatic pressure bearings, and a plurality of rollers are disposed at intervals on the hydrostatic pressure bearing portion. 2. The belt type continuous casting machine according to claim 1, wherein at least one of the rollers disposed in the hydrostatic bearing section is driven to assist the movement of the belt. 3. The belt-type continuous casting machine according to claim 1, wherein a roller is disposed at the end of each hydrostatic bearing.