KR20130075276A - Guide roller assembly of continuous casting apparatus - Google Patents

Abstract

PURPOSE: A guide roller assembly of a continuous casting machine is provided to prevent surface wear of a roller which is caused by rising temperature of slab when the edge parts of both sides of the slab in the width direction of the slab is mildly cooled, and to reduce the changes of material properties which are caused by high temperature, thereby preventing strength and rigidity of the roller from being lowered. CONSTITUTION: A guide roller assembly (100) of a continuous casting machine (1) comprises a pair of both side guide roller units (110,120) and a center guide roller unit (130). The both side guide roller units are positioned on both sides of a slab respectively in the width direction of the slab, and integrated with roll shafts and a roll shells. The guide roller units form extension shafts which have roll shafts which are extended, and connected with each other. The center guide roller unit is positioned in the center of the slab in the width direction of the slab, and the roll shell is assembled on the extension shaft.

Description

Guide roller assembly of continuous casting device {GUIDE ROLLER ASSEMBLY OF CONTINUOUS CASTING APPARATUS}

The present invention relates to a guide roller of a continuous casting apparatus, and more particularly, to a guide roller assembly of a continuous casting apparatus which is installed in the upper and lower segments of the segment in the continuous casting apparatus to guide and press the cast.

In general, a continuous casting process is a process of continuously solidifying molten steel in a solid form in a molten form.

1 is a schematic diagram of a typical continuous casting apparatus strand. As shown in FIG. 1, molten steel is injected into a tundish 13 through a long nozzle from a ladle 11 in which molten steel after the refining process is contained, and a tundish ( The molten steel temporarily stored in 13 is injected into the mold 15 through a molten steel transmission device (not shown) located between the tundish 13 and the mold 15, and the primary cooling in the mold 15 is performed. , It refers to a series of processes to produce the cast 3, such as billet (bloom), bloom, slab (slab), etc. by solidification through the secondary cooling in the lower part of the mold (15).

The molten steel discharged through the mold (3) is the upper and lower guide rollers provided in the segment (17) of the continuous casting apparatus 1 in a state that the surface is slightly solidified through the primary cooling in the mold (3) ( 20), the cooling water is sprayed for rapid solidification of the molten steel is continuously changed to the shape of the slab (3).

FIG. 2 is a perspective view of the segment shown in FIG. 1. FIG. As shown in Figure 2, the guide roller 20 provided in the segment is composed of a combination of the upper guide roller and the lower guide roller generally composed of 5 to 10 rollers between the molten steel is cast and rolled into the slab Are manufactured. Reference numerals 18 and 19 not described in FIG. 2 denote upper and lower frames, respectively. The guide roller 20 is divided into an integrated roller formed of one roller and a split roller divided into several rollers. In addition, the split roller is divided into a structure in which the divided portion is cut and a structure in which a plurality of roll shells are assembled on one roll shaft. Here, the divided roller is advantageous to deformation due to the load generated during casting, compared to the integrated roller, and the roller having the divided part is excellent in maintenance, such as disassembly and assembly, and the structure using the roll shaft and the roll shell is It is the most resistant to vertical and horizontal parts, so it is suitable for high loads.

3 and 4 are cross-sectional views of the strand guide roller according to the prior art.

Guide roller 20 of the continuous casting device according to the prior art, as shown in Figure 3, a structure in which each roll shell (roll shell) (23) is assembled on one roll shaft (roll shaft) (21) As shown in FIG. 4 or in the form of an integrated roll 25, each bearing support portion 17 has a structure that is completely divided so that the cooling capacity of the cast pieces is equal in the width direction. In addition, the guide roller 20 has a structure that is cooled by the cooling water supplied along the cooling water passages 21a and 25a mostly formed therein, and the guide roller to be cooled is not only resistant to wear as well as weaker than the guide roller that is not cooled. It is known to have a cooling effect of the slab 3 of 30%.

In general, however, when the widthwise temperature of the slab 3 is measured in the continuous casting device 1, it can be seen that it is the highest near both sides (left and right) of the slab 3 in the width direction as shown in FIG. (Graph solid line ①), thereby causing solidification nonuniformity in the width direction of the cast piece 3, resulting in width deviation of the cast piece 3 in the width direction.

In addition, when casting a crack-sensitive steel grade, both sides of the slab (3) in the width direction in order to prevent the occurrence of cracks in the slab (3) is not sprayed or sprayed very weakly, in this case, the slab (3) in the width direction The temperature unevenness becomes more severe, and the guide rollers on both sides in the width direction of the cast 3 have a problem that wear of the roller becomes severe due to an increase in the surface temperature of the roller.

In addition, the structure in which the guide roller 20 is in the form of an integrated roll absorbs heat of the slab 3 and transfers it to the coolant well. Due to thermal contact resistance, the heat transfer rate drops.

The present invention has been made to solve the above problems, to provide a guide roller assembly of a continuous casting device that can produce a cast without a quality deviation in the width direction by preventing the non-uniform width in the casting direction in the continuous casting process do.

In addition, the present invention is to provide a guide roller assembly of the continuous casting device that can prevent the surface wear of the roller due to the temperature rise of the cast slab when the width direction of both edges of the cast slab cold.

The present invention is a guide roller assembly for guiding and compressing the cast in a continuous casting device, each of which is located on both sides in the width direction of the cast, roll shaft and roll shell is formed integrally, each roll shaft is extended to be connected to each other A pair of both guide roller parts forming a shaft; And a guide roller assembly of a continuous casting apparatus, which is positioned at the center in the width direction of the cast piece, and includes a central guide roller portion on which the roll shell is assembled on the extension shaft.

The present invention also discloses a guide roller assembly of a continuous casting apparatus, characterized in that a cooling water passage is formed such that cooling water flows along a shaft center of both the guide roller portions and the central guide roller portion.

In addition, the guide roller of the continuous casting device, characterized in that a relative movement preventing portion for preventing relative movement of the extension shaft and the roll shell is provided on the interface between the extension shaft of the both guide rollers and the roll shell of the central guide roller portion. Initiate the assembly.

In addition, the extension shaft discloses a guide roller assembly of a continuous casting device, characterized in that each roll shaft extending from both guide roller parts are overlapped at the center portion.

In addition, the overlap coupling portion of the extension shaft discloses a guide roller assembly of a continuous casting device, characterized in that the concave, convex coupling structure.

In addition, it discloses a guide roller assembly of the continuous casting device, characterized in that the sealing coupling to prevent leakage of the cooling water is provided in the overlapping coupling portion of the extension shaft.

The guide roller assembly of the continuous casting device according to the present invention has the following effects.

(1) The guide roller assembly of the continuous casting apparatus according to the present invention can produce a cast of uniform quality in the width direction by preventing the cross-direction solidification non-uniformity of the cast by varying the cooling capacity of both ends and the center of the guide roller Has an effect.

(2) The guide roller assembly of the continuous casting device according to the present invention can reduce the surface wear of the roller that occurs when the cooling water is not sprayed on the slabs of both edges of the guide roller or weakly cooled to prevent the crack of the cast steel, It is possible to reduce the change in the properties of other materials at a high temperature, thereby having an effect of preventing the degradation of the strength and stiffness of the roller.

(3) In the guide roller assembly of the continuous casting apparatus according to the present invention, since only the center portion of the guide roller needs to be assembled with the roll shell on the roll shaft, disassembly and assembly of the guide roller is simple, and the maintenance and repair time of the roller is shortened. By doing so, the productivity of the continuous casting equipment can be improved.

1 is a schematic diagram of a typical continuous casting apparatus strand.
FIG. 2 is a perspective view of the segment shown in FIG. 1. FIG.
3 and 4 are cross-sectional views of the strand guide roller according to the prior art.
5 is a cross-sectional view of the guide roller assembly of the continuous casting device according to a preferred embodiment of the present invention.
6 is a graph showing the slab width direction temperature distribution.
7 is a view showing the cross-sectional temperature distribution and thermal shear rate of the guide roller is assembled a roll shell on the roll shaft.
8 is a view showing the cross-sectional temperature distribution and thermal shear rate of the guide roller in which the roll shaft and the roll shell are integrally formed.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Prior to the description of the present invention, the guide roller assembly 100 of the continuous casting device 1 according to a preferred embodiment of the present invention can be applied in various ways regardless of the number of the number of three or five divided rollers It may be, but will be described below by applying to the guide roller assembly 100 is mainly produced in a three-splitting roller form.

5 is a cross-sectional view of the guide roller assembly of the continuous casting device according to a preferred embodiment of the present invention.

As shown in FIG. 5, the guide roller assembly 100 of the continuous casting apparatus 1 according to the preferred embodiment of the present invention includes both guide roller parts 110 and 120 and a center guide roller part 130. It is used to guide and press the cast 3 in the casting device 1.

Both guide roller parts 110 and 120 are constituted in pairs and are located on both sides (left and right) in the width direction of the cast steel 30. In addition, the guide roller parts 110 and 120 are not manufactured by assembling the roll shaft and the roll shell separately. Instead, the roll shaft 111 and the roll shell 112 are manufactured in one body, that is, in one-piece body, thereby improving heat transfer efficiency. In addition, both the guide roller parts 110 and 120 have respective roll shafts 111 and 121 extending to the center to each other. The extension shaft 131 is connected.

The extension shaft 131 is coupled to each of the roll shafts 111 and 121 extending from both guide roller parts 110 and 120 at the center. The overlapping coupling portion of the extension shaft 131 has a concave and convex coupling structure. In addition, a sealing portion 137 is provided on the central surface of the overlapping coupling portion of the extension shaft 131 to prevent leakage of the cooling water. The sealing unit 137 may use an O-ring having a circular cross section.

The center guide roller part 130 is located in the width direction center of the cast piece 3. The center guide roller 130 is manufactured in the form of assembling the roll shell 132 on the central extension shaft 131 of both guide rollers (110, 120). That is, the shaft for assembling and supporting the roll shell 132 of the central guide roller 130 uses half of the extension shaft 131 which is formed to extend from both integral types.

In addition, the cooling water path 101 is formed such that the cooling water flows along the centers of both the guide roller parts 110 and 120 and the center guide roller part 130. That is, the cooling water path 101 is formed at the center of both guide rollers 110 and 120 and the center of the central extension shaft 131, and the diameter of the cooling water path 101 is preferably about 30 to 35 mm.

In addition, the boundary surface between the extension shaft 131 of both guide roller parts 110 and 120 and the roll shell 132 of the center guide roller part 130 is for preventing relative rotational movement of the roll shell 132 with respect to the extension shaft 131. Relative movement prevention unit 135 is provided. Here, the relative movement prevention unit 135 can be manufactured in the form of a parallel key, the parallel key is installed is inserted into the key groove formed in the longitudinal direction on the extension shaft 131 and the roll shell 132.

In addition, the rotary joint 141 is installed at both ends of the guide rollers 110 and 120 like the conventional rollers, so that the coolant supply and discharge can be smoothed even when the guide roller rotates.

In addition, the guide roller has four bearings 143 to support the divided portion to enable rotation, each bearing 143 is installed in a bearing housing (not shown). Here, the bearing housing has a structure in which a lubricating oil supply for lubricating the bearing 143 and a cooling water supply for self cooling are provided. In addition, in the present embodiment, a roller bearing having a self-aligning function is generally used, but various types of bearings may be used without being limited thereto.

6 is a graph showing the slab width direction temperature distribution.

As shown in FIG. 6, in the guide roller assembly 100 of the continuous casting apparatus 1 according to the preferred embodiment of the present invention, the width direction temperature of the slab 3 is measured, and the center guide roller 130 is assembled. Since the heat transfer efficiency is better in the integrated guide roller parts 110 and 120, it is possible to confirm that the cooling capacity is increased near both sides (left and right) in the width direction of the cast 3, thereby lowering the temperature (graph dotted line ②).

7 and 8 are diagrams showing the temperature distribution and the heat transfer rate by performing a two-dimensional heat transfer analysis by computer simulation, Figure 7 is a view showing the cross-sectional temperature distribution and thermal shear rate of the guide roller assembled on the roll shaft, 8 is a view showing the cross-sectional temperature distribution and thermal shear rate of the guide roller in which the roll shaft and the roll shell are integrally formed.

In FIG. 7, the case of the assembled guide roller in which the roll shell is assembled on the roll shaft shows discontinuous temperature distribution at the assembly interface. On the other hand, in the case of the integral guide roller in which the roll shaft and the roll shell are integrally formed in Figure 8 shows a continuous temperature distribution because there is no interface.

[Table 1] shows the heat transfer rate and the surface temperature of the rollers for the two cases of the assembled and integrated guide rollers by computer simulation.The heat transfer rate is more than twice that of the integrated type and the surface temperature of the roller is 100. You can see that it is too low.

Assembled guide roller Integral Guide Roller Max. temp. 784 (℃) 678 (℃) Q / mm 7.6 (W / mm) 15.6 (W / mm)

In the present invention, the outer surface of the guide roller assembly 100 is in contact with the slab 3 to absorb the heat during the continuous casting process. The absorbed heat is transferred to the radial center of the guide roller assembly 100 in which the coolant flows, and is absorbed into the coolant path 101 by convective heat transfer at the coolant passage boundary and discharged to the outside.

At this time, both the guide rollers 110 and 120 have a structure in which the roll shafts 111 and 121 and the roll shells 112 and 122 are integrated, so that the heat transfer efficiency is excellent and the surface temperature of the roller is kept low. On the other hand, the center guide roller 130 is a structure in which the roll shell 132 is assembled on the central extension shaft 131 of both guide rollers (110, 120), the heat transfer efficiency at the interface due to the heat transfer efficiency is much lower than the one-piece The surface temperature of the roller is also relatively high.

Therefore, the guide roller assembly 100 of the continuous casting device 1 according to the present invention is uniform in the width direction by preventing the coagulation unevenness in the width direction of the slab 3 by varying the cooling capacity of both ends and the center of the roller. Can produce cast iron of quality. In addition, the present invention can reduce the surface abrasion of the roller generated when the cooling water is not sprayed on the edge cast slab (3) of the guide roller to prevent cracking of the cast slab (3) or weak cooling, and different materials at high temperatures It is possible to reduce the change in physical properties and to prevent the strength and stiffness of the roller from being lowered.

While the present invention has been described in connection with certain exemplary embodiments, it will be understood by those skilled in the art that various changes may be made without departing from the scope of the present invention. In addition, the description in parentheses among the description of the claims is intended to prevent the ambiguity of the description, and the scope of the claims should be interpreted including all the descriptions in the parentheses.

1: continuous casting apparatus 100: guide roller assembly
110,120: Both guide rollers 111,121: Roll shaft
112, 122, 132: roll shell 130: center guide roller portion
131: extension shaft 135: relative movement prevention
137: seal 143: bearing

Claims (6)

In the guide roller assembly for guiding and pressing the cast in a continuous casting device,
A pair of both guide rollers respectively positioned on both sides in the width direction of the cast piece, and having a roll shaft and a roll shell formed integrally with each roll shaft extending to form extension shafts connected to each other; And
A guide roller assembly of the continuous casting device, which is located in the center of the width direction of the cast steel, and comprises a central guide roller portion on which the roll shell is assembled on the extension shaft. The guide roller assembly of claim 1, wherein a cooling water path is formed such that cooling water flows along the centers of both the guide roller parts and the center guide roller part. The continuous casting part of claim 1, wherein a relative movement prevention part is provided at an interface between the extension shafts of the guide roller parts of the both guide rollers and the roll shell of the central guide roller part to prevent relative movement of the extension shaft and the roll shell. Guide roller assembly of the device. The guide roller assembly of claim 1, wherein each of the extension shafts overlaps with each other in the center of each of the extension shafts extending from the guide roller portions. The guide roller assembly of claim 4, wherein the overlap coupling portion of the extension shaft has a concave and convex coupling structure. 6. The guide roller assembly of claim 5, wherein the overlap coupling part of the extension shaft is provided with a sealing part to prevent leakage of cooling water.

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