KR101914082B1 - Dummy bar - Google Patents

Abstract

The present invention relates to a dummy bar, and more particularly, to a dummy bar for withdrawing a cast from a mold.
A dummy bar according to an embodiment of the present invention includes: a first connection portion having a protrusion formed at one end; And a second connection part provided on a side surface of the first connection part and configured to be mounted on the protrusion and rotatably installed on one side of the first connection part, And the support pin has an outer circumferential surface on which a distance from the rotation axis changes.

Description

Dummy bar {DUMMY BAR}

The present invention relates to a dummy bar, and more particularly, to a dummy bar for withdrawing a cast from a mold.

In general, continuous casting equipment is produced from steel making furnace, molten steel delivered to ladle is supplied to the tundish, and supplied to the mold with lower opening through the immersion nozzle installed at the bottom of the tundish, .

The molten steel supplied to the mold is cast into a cast steel having a predetermined width and thickness while being cooled through the segment equipment. Since such a cast can not be smoothly transferred to the curved portion of the lower portion of the mold and the end of the segment equipment only by its own weight, a dummy bar is connected to the end of the casting, and the cast is pulled out from the mold and the segment.

The dummy bar is pulled out by pulling out the dummy bar while the dummy bar is inserted into the inside of the mold at the beginning of the continuous casting. Such a dummy bar is provided with a dummy bar head connected to the cast, Are connected through a connection link. The rear end of the dummy bar body is provided with a dummy bar tail connected to a winch hook or the like to hoist the dummy bar.

However, the dummy bar has a structure in which a plurality of dummy bar bodies are connected to each other through a connecting link, so that there is a problem that deflection occurs due to abrasion of the connecting link in long-term use.

In other words, in general, the dummy bars are formed such that the dummy bars are folded in only one direction while the dummy bar bodies are horizontally arranged. In the long-term use of the dummy bars, The dummy bar is sagged in the direction of the arrow. This causes the dummy bars to collide with the lower rollers supporting the dummy bars when moving within the segments.

When a sagging phenomenon occurs in the dummy bar, the dummy bar tail collides with the lower roller supporting the dummy bar during casting, and when the dummy bar is loaded downward into the mold, the dummy bar head collides with the lower roller. This problem is more serious when the dummy bars are charged down into the mold, because the speed at which the dummy bars move is generally faster than the speed at which the dummy bars move during casting.

Such a collision causes a phenomenon in which the molten steel contained in the molten steel is entangled during casting, so that the formation of the solidification layer at the initial stage of the casting may become unstable and the lower roller or the dummy bar of the segment may be broken, There is a problem that the risk of accident is increased.

KR 10-0862843 B1 KR 10-2012-0110911 A

The present invention provides a dummy bar capable of withdrawing a cast from a mold.

In addition, the present invention provides a dummy bar capable of preventing an impact applied to a casting facility at the time of movement.

A dummy bar according to an embodiment of the present invention includes a first connection portion having a protrusion formed at one end thereof; And a second connection part provided on a side surface of the first connection part and configured to be mounted on the protrusion and rotatably installed on one side of the first connection part, And the support pin has an outer circumferential surface on which a distance from the rotation axis changes.

The support pin may be eccentrically installed with respect to the rotation shaft.

The axial end surface of the support pin may have a polygonal shape.

The polygon may have a plurality of sides having different distances from the rotation axis.

The plurality of sides may be formed such that the distance from the rotation axis sequentially increases.

The plurality of sides may be formed such that distances from the rotation axis increase at equal intervals.

A plurality of the first connection portions may be spaced apart from each other in the lateral direction, and the second connection portion may be installed with one end overlapping the first connection portions.

The support pins may be installed on both sides of the second connection portion.

The second connection portion may further include a connection pin for interconnecting the support pins.

The support pin may have a shaft cross section symmetrical with respect to the connection pin.

The first connection part and the second connection part may be provided in plural, and the plurality of first connection parts and the second connection part may be alternately installed.

The first connection part or the second connection part may be provided on the dummy bar head.

The first connection part or the second connection part may be provided on the dummy bar tail.

According to the dummy bar according to the embodiment of the present invention, when the support pin having the outer circumferential surface changing the distance from the rotation axis is rotated, and the deflection of the dummy bar is caused by the wear of the connection shaft portion, .

In addition, the axial end surface of the support pin with respect to the rotation axis is formed in a polygonal shape, so that the support pin can be firmly supported on the protrusion by increasing the contact area with the protrusion. In addition, the adjustment width can be easily changed according to the rotation angle of the support pin by forming the plurality of sides constituting the polygon so that the distance from the rotation axis increases sequentially.

This makes it possible to prevent collision with peripheral equipment such as a roller during the movement of the dummy bar, thereby shortening the working time and reducing the risk of accident.

1 shows a general continuous casting apparatus;
2 is a view showing a state in which a deflection of a dummy bar occurs due to abrasion of a connecting shaft;
3 is a view showing a state where a first connection part and a second connection part are connected according to an embodiment of the present invention;
4 is a view showing a state in which a deflection of a dummy bar is compensated by rotating a support pin according to an embodiment of the present invention;
5 is a view showing a state of an axial end surface of a support pin according to an embodiment of the present invention.
6 to 8 are views showing a state in which deflection of a dummy bar is compensated when a plurality of first connection portions and second connection portions are alternately installed.

The dummy bar according to the present invention compensates the sagging due to wear of the connecting link, thereby providing a technical feature that can prevent the impact applied to the casting equipment during the movement.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, Is provided to fully inform the user. Wherein like reference numerals refer to like elements throughout.

Generally, a continuous casting apparatus is made of a steel pipe produced in a steelmaking furnace, and a molten steel conveyed to a ladle is received in a tundish and supplied to a mold to continuously produce a cast steel having a predetermined size.

FIG. 1 is a view showing a general continuous casting apparatus, and FIG. 2 is a view showing a state where deflection of a dummy bar occurs due to abrasion of a connecting shaft.

1 and 2, the continuous casting machine includes a ladle 20 provided in a ladle turret, a ladle 20 having a ladle 20 with impurities removed and chemical components adjusted therein, Is poured into a tundish (30) through a nozzle made of a cylindrical refractory brick.

Molten steel stored in the tundish 30 is injected into the mold 40 through an immersion nozzle made of a cylindrical refractory brick, and is cast into a slab on a large plate by a mold. Since the mold 40 is provided with a cooling mechanism therein, the cast steel 40 is cooled while the molten steel flows therein, and the cast steel 50 having a cross section corresponding to the cross section of the casting mold 40 is cast.

A dummy bar 10 for guiding the casting 50 is introduced into the open lower portion of the mold 40 in the mold 40 and the initial molten steel introduced into the mold 40 is poured The molten steel solidified in the casting connection groove 72 is caught and introduced into the casting connection groove 72 of the bar head 12, A plurality of rollers 80 provided on a cooling base for forming the casting roll 50 are driven and the dummy bars 60 lead the solidified castings 50 and move between the rollers through which the cooling water is injected to continuously produce the castings 50 .

The cast steel 50 solidified by the dummy bar 10 is pulled out at the beginning of the casting of the molten steel but once the cast steel 50 once solidified passes between the rollers 80, I will not. Thus, the dummy bar 60 is lifted up by the separating device, and the continuously cast piece 50 is cut to a predetermined length by the cutter 90 and conveyed to the collecting hall by the table roller 82. [

On the other hand, the mold (40) of the continuous casting facility has no bottom, unlike the casting mold. Therefore, when the molten steel is injected into the casting mold 40, a floor is required to prevent the molten steel from being exposed, and the dummy bar head 12 plays a role. The leading end portion of the dummy bar 10, that is, the portion corresponding to the bottom of the mold is called a dummy bar head 12, and the initial molten steel is solidified at this portion and joined with the dummy bar 10 and pulled out by the roller 80.

As shown in FIG. 2 (a), the dummy bar 10 is rotatably coupled to the connection shaft 5 through a plurality of connection portions. The first connection part includes a first body part 1 and a protruding part 2 formed at one end of the first body part 1. The second connection part includes a second body part 3, And a support pin (4) provided on the side surface of the base (3). The support pin 4 is configured to rest on the protruding portion 2 to limit the rotational direction of the first connection portion with respect to the second connection portion and maintain the horizontal state.

However, when the dummy bar 10 is used for a long period of time, as shown in FIG. 2 (b), abrasion occurs at a portion of the connection shaft 5 connecting the first connection portion and the second connection portion. The dummy bar 10 can not be maintained in a horizontal state due to the abrasion of the connection shaft 5, but is sagged downward. Also, since the dummy bar 10 has a structure in which a plurality of connection portions are interconnected, the deflection of the dummy bar 10 is more serious as the number of connection portions increases.

In this way, when the dummy bar 10 deflects, the dummy bar 10 collides with the lower roller that supports the dummy bar 10 from below. In the vertically curved casting equipment which is connected to the vertical portion, the curved portion and the horizontal portion, the curved portion is closely arranged with the lower rollers so that the possibility of the dummy bar 10 colliding with the lower roller is low, So that they collide with the dummy bar 10.

The collision between the lower roller and the dummy bar 10 occurs mainly at both ends of the dummy bar 10, that is, at the dummy bar head and the dummy bar tail. That is, at the time of casting, the dummy bar moves downward and the dummy bar tail collides with the lower roller disposed in the horizontal part. When the dummy bar is loaded downward in the mold, the dummy bar moves upward and the dummy bar head is placed in the horizontal part And the lower roller. This problem is more serious when the dummy bars are charged down into the mold, because the speed at which the dummy bars move is generally faster than the speed at which the dummy bars move during casting.

FIG. 3 is a view showing a state in which the first connecting portion and the second connecting portion are connected to each other according to the embodiment of the present invention. FIG. 4 is a perspective view illustrating a state in which the deflection of the dummy bar is compensated by rotating the supporting pin 126 according to the embodiment of the present invention. Fig. 5 is a view showing an axial cross-sectional view of the support pin 126 according to the embodiment of the present invention.

3 to 5, the dummy bar according to the embodiment of the present invention includes a first connection portion having a protrusion 114 formed at one end thereof; And a second connection part provided on the side surface of the first connection part and configured to be rotatably mounted on the side surface of the first connection part and having a support pin 126 mounted on the protrusion part 114, 126 are rotatably disposed about a rotation axis O extending in a lateral direction of the second connection portion and the support pin 126 has an outer circumferential surface where a distance from the rotation axis O changes.

The first connection portion includes a first body portion 112 extending in the longitudinal direction and a protrusion 114 formed at at least one end of the first body portion 112. The protrusion 114 may be partially protruded from one end of the first body part 112 and may protrude from the lower end of the first protrusion 114.

The second connection portion includes a second body portion 122 extending in the longitudinal direction and a support pin 126 installed on at least one side of the second body portion 122. The second body portion 122 is rotatably mounted on the first body portion 112 by a connection shaft 150 that is overlapped on the first body portion 112 and connects the first body portion 112 and the second body portion 122 do.

The first body part 112, the protrusion part 114 and the second body part 122 constituting the first connection part and the second connection part are the same as those generally used in the connection structure of the dummy bar, It will be omitted.

The support pin 126 is installed on the side surface of the second connection portion and is seated on the projection portion 114 in accordance with the rotation of the first connection portion. The support pin 126 is rotatably installed around a rotation axis O extending in a lateral direction of the second connection part, that is, in a lateral direction of the second body part 122, O from the outer circumferential surface.

The support pin 126 has an outer circumferential surface that varies in distance from the rotation axis O. When the support pin 126 is seated on the protrusion 114, the support pin 126 is rotated to rotate the rotation axis O, (114).

For this purpose, the support pin 126 may have the shape of a columnar or polygonal column. That is, the support pin 126 may have various pillar shapes having an outer circumferential surface where the distance from the rotation axis O changes. Here, the end surface of the support pin 126, that is, the end surface in the direction perpendicular to the rotation axis O, may have various shapes.

For example, the axial end surface of the support pin 126 may have a circular or elliptical shape. When the shaft end of the support pin 126 has a circular shape, the center of the circular shape may be eccentric from the rotation axis O so that the support pin 126 has an outer circumferential surface whose distance from the rotation axis O changes. When the shaft end of the support pin 126 has an elliptical shape, the outer circumferential surface of the shaft end surface is formed so that the distance from the rotation axis O changes. In this case, the center of the shaft end surface and the rotation axis O are eccentric It may not be eccentric.

The shaft end surface of the support pin 126 may have a polygonal shape. In this case, the polygon may have a plurality of sides having different distances from the rotation axis O. That is, when the shaft end surface of the support pin 126 has a pentagonal shape as shown in FIG. 5, the respective sides of the pentagon are arranged to have different distances from the rotation axis O.

In addition, when the support pin 126 has a polygonal shape, a plurality of polygonal sides may be formed so that the distance from the rotation axis O sequentially increases. 5, the distance from the rotation axis O to the first side is d1, the distance from the rotation axis O to the second side is d2, the distance from the rotation axis O to the third side is d3, When the distance of the fourth side is d4 and the distance of the fifth side from the rotation axis O is d5, d1 to d5 may have a sequentially increasing value. In addition, d1 to d5 may have a value such that the distance from the rotation axis O increases at equal intervals. For example, when d1 has a value of 10 mm, d2 is formed to have a value of 11 mm, d3 is set to 12 mm, d4 is set to 13 mm, d5 is set to 14 mm, And may be formed to increase sequentially.

Referring to FIG. 4, a process of compensating deflection of the dummy bar according to an embodiment of the present invention will now be described. As shown in FIG. 4A, first and second connection portions are formed on the protrusion 114 The support pin 126 is seated and maintained in a horizontal state. Here, the axial end surface of the support pin 126 has a pentagonal shape, and the distance between the rotation axis O and the protruding portion 114 has a value of d1.

Wear of the connection shaft 150 occurs due to long-term use of the dummy bar. 4 (b), even when the distance between the rotation axis O and the protruding portion 114 is maintained at the same value d1, the first connection portion can not maintain a horizontal state with respect to the second connection portion , And a phenomenon of sagging downward occurs.

Here, as shown in Fig. 4 (c), the support pin 126 is rotated about the rotation axis O to adjust the distance between the rotation axis O and the projection 114. [ That is, since d2 has a value greater than d1, when the distance between the rotation axis O and the protrusion 114 is increased to the value d2 by rotating the support pin 126, So that it is possible to maintain the horizontal position.

In the above description, the process of compensating the deflection by changing the distance between the rotation axis O and the protruding portion 114 from d1 to d2 by rotating the support pin 126 has been described. However, more deflection is generated with respect to the first connection portion It goes without saying that the support pin 126 may be sequentially rotated at a predetermined angle to compensate the dummy bar in a horizontal state. That is, the distance between the rotation axis O and the projection 114 is gradually changed from d1 to d5 so that the horizontal state can be accurately adjusted when the support pin 126 is placed on the projection 114. [

As shown in FIG. 3, a plurality of first connection portions may be spaced apart from each other in the lateral direction, and a second connection portion may be provided at one end between the first connection portions, Or may be installed in a superimposed manner. In this case, the support pins 126 may be respectively installed on both side surfaces of the second body portion 122, and may be respectively seated on the protrusions 114 provided in the first connection portions.

The second connection portion may further include a connection pin for connecting the support pins 126 installed on both sides of the second body portion 122, respectively. Herein, the connection pin is provided to penetrate the second body portion 122, and when one of the support pins 126 installed on both side surfaces of the second body portion 122 is rotated And may be integrally formed with each support pin 126 so as to simultaneously rotate the other support pin 126. The connection pin may be formed to have a circular axial end face about the rotation axis O and be rotatable about the rotation axis O in the second body part 122.

Further, the support pins 126, which are respectively installed on both side surfaces of the second body portion 122, may have axial end surfaces symmetrical with respect to the connection pin. This is to adjust the distance between the rotation axis O and the protrusion 114 by the rotation of the support pin 126 in the same manner with respect to the plurality of protrusions 114 provided in the plurality of first connection parts, When the distance between the rotation axis O and the protrusion 114 is adjusted by rotating any one of the support pins 126 provided on both side surfaces of the support portion 126, The distance between the rotation axis O and the protrusion 114 can be adjusted to be the same.

FIGS. 6 to 8 are views showing how deflection of a dummy bar is compensated when a plurality of first connection portions and second connection portions are alternately installed.

6 to 8, a dummy bar according to an embodiment of the present invention includes a plurality of first connection portions and a plurality of second connection portions, and the first connection portions and the second connection portions may be alternated. That is, the first connection portion and the second connection portion are alternately arranged in the longitudinal direction, and one end of the second connection portion is rotatably coupled to the first connection portion by one connection shaft 150, 1 coupling portion by another coupling shaft 160. [0031] As shown in FIG.

To this end, the first connection part may further include a support pin rotatably installed on the side surface, and the second connection part may further include a protrusion 124 formed at one end. The support pin 126 of the second connection portion is seated on the protrusion 114 of the first connection portion and the support pin (end surface 136A) of the other first connection portion is seated on the protrusion portion 124 of the second connection portion A dummy bar can be formed.

Here, the first connection portion or the second connection portion may be provided on the dummy bar head, or the first connection portion or the second connection portion may be provided on the dummy bar tail. That is, the portion of the dummy bar colliding with the lower roller supporting the dummy bar differs depending on the moving direction of the dummy bar. That is, during casting of the cast steel, the dummy bar may move downward and the dummy bar tail may collide with the lower roller. When the dummy bar is mounted in the mold at the bottom, the dummy bar head may collide with the lower roller.

Therefore, in the dummy bar according to the embodiment of the present invention, the first connecting portion or the second connecting portion is provided in the dummy bar head or the dummy bar tail, and when the sagging occurs in the dummy bar head or the dummy bar tail, So that the dummy bar head or the dummy bar tail itself can be maintained in a horizontal state directly.

The first connection part and the second connection part according to the embodiment of the present invention may be provided both in the dummy bar head constituting the dummy bar, in the dummy bar body divided into a plurality of parts and in the dummy bar tail, It may be provided only in a part of the dummy bar body from the bar body or the dummy bar tail.

6 to 8, when a plurality of first connection portions and second connection portions are provided and alternately installed, the support pin 126 of the second connection portion is rotated so that the interval between the rotation axis and the protrusion 114 is changed from d1 to d2 The first connection part at the tip can be moved by the height h1 to compensate for the horizontal state. When the distance between the rotation axis and the protruding portion 124 is adjusted from d1 to d2 by rotating the support pin of the first connection portion disposed at the rear end of the second connection portion, the first connection portion at the tip moves by the height of h2, Can be compensated. The dummy bar head moves to a height of h1 by the rotation of the support pin 126 provided at the second connection portion to compensate for the horizontal state, The dummy bar head moves to a height of h2 by the rotation of the support pin of the first connection portion disposed at the rear end of the second connection portion to compensate for the horizontal state. In other words, as the support pin farther from the dummy bar head is rotated, the dummy bar moves higher and can compensate for the horizontal state. Therefore, a part of the dummy bar body or part of the dummy bar body Even when the first connecting portion and the second connecting portion according to the embodiment of the present invention are applied only to the dummy bar body, the horizontal state of the dummy bar head or the dummy bar tail can be adjusted to a sufficient height.

According to the dummy bar according to the embodiment of the present invention, when the support pin having the outer circumferential surface changing the distance from the rotation axis is rotated, and the deflection of the dummy bar is caused by the wear of the connection shaft portion, .

In addition, the axial end surface of the support pin with respect to the rotation axis is formed into a polygonal shape, so that the support pin can be firmly supported on the protrusion by increasing the contact area with the protrusion. In addition, the adjustment width can be easily changed according to the rotation angle of the support pin by forming the plurality of sides constituting the polygon so that the distance from the rotation axis increases sequentially.

This makes it possible to prevent collision with peripheral equipment such as a roller during the movement of the dummy bar, thereby shortening the working time and reducing the risk of accident.

While the preferred embodiments of the present invention have been described and illustrated above using specific terms, such terms are used only for the purpose of clarifying the invention, and the embodiments of the present invention and the described terminology are intended to be illustrative, It will be obvious that various changes and modifications can be made without departing from the spirit and scope of the invention. Such modified embodiments should not be individually understood from the spirit and scope of the present invention, but should be regarded as being within the scope of the claims of the present invention.

10: Dummy bar 12: Dummy bar head
20: ladle 30: tundish
40: Mold 50: Cast steel
80: roller 90: cutter
112: first body part 114:
122: second body part 126: support pin
150: connection axis

Claims (13)

A first connection portion having a protrusion formed at one end thereof; And
And a second connecting part provided on the side surface of the first connecting part and rotatably mounted on the side surface of the first connecting part,
Wherein the support pin is rotatably installed around a rotation axis extending in a lateral direction of the second connection portion,
Wherein the support pin has an outer circumferential surface in which a distance from the rotation axis changes.
The method according to claim 1,
And the support pin is eccentrically installed with respect to the rotation shaft.
The method according to claim 1,
And the shaft end face of the support pin has a polygonal shape.
The method of claim 3,
Wherein the polygon has a plurality of sides having different distances from the rotation axis.
The method of claim 4,
Wherein the plurality of sides are formed so that the distance from the rotation axis sequentially increases.
The method of claim 5,
Wherein the plurality of sides are formed such that distances from the rotation axis increase at equal intervals.
The method according to claim 1,
Wherein a plurality of the first connection portions are spaced apart from each other in the lateral direction,
And the second connection portion is installed with one end overlapping between the first connection portions.
The method of claim 7,
And the support pins are respectively installed on both sides of the second connection portion.
The method of claim 8,
The second connection portion
And a connection pin for interconnecting the support pins.
The method of claim 9,
Wherein the support pin has a shaft cross section symmetrical with respect to the connection pin.
The method according to claim 1,
A plurality of first connection portions and second connection portions are provided,
Wherein the plurality of first connection portions and the plurality of second connection portions are alternately installed.
The method according to claim 1,
Wherein the first connection portion or the second connection portion is provided in the dummy bar head.
The method according to claim 1,
Wherein the first connection part or the second connection part is provided on the dummy bar tail.

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