JPS6124361Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a twin dummy bar in continuous casting equipment.

In continuous casting equipment for both slabs and twin blooms, when continuously casting slabs, a foot roll exclusively for slabs is placed above the guide roll group 1 that constitutes the slab conveyance path, as shown in Figure 1a and b. When continuously casting twin blooms, the mold 3 with foot rolls 2 and the support roll device 4, which are exclusively for slabs, are installed, as shown in FIGS. 2a and 2b. Generally, they are removed all at once, and a mold 6 with a foot roll 5 dedicated to twin bloom and a support roll device 7 are placed above the guide roll group 1. Therefore, the guide roll group 1 serves both as a slab and as a twin bloom. In the case of continuous slab casting shown in FIGS. 1a and 1b, the slab dummy bar 8 on a dummy bar (not shown) is inserted into the mold 3 from above, and the tail portion 8A is inserted into the drive roll 1A of the guide roll group 1. 1, release the hanging support of the head part 8B, rotate the drive roll 1A, pull out the slab dummy bar 8 in the direction of arrow A, and insert the head part 8B into the mold 3 as shown in FIG. 1a. , the continuous casting can be started, but at this time, as shown exaggeratedly in FIG.
The drive roll 1A and the slab dummy bar 8 are in a state where they are in only point contact. Therefore, when the slab dummy bar 8 is pulled out in the direction of arrow A, both side edges 8C of the slab dummy bar 8 are pulled out.
is pressed by the drive roll 1A, but since the pressing forces cancel each other out, the slab dummy bar 8 is pulled out straight in the direction of arrow A, and no problem occurs. However, problems arise in the case of continuous twin bloom casting. That is, both rod-shaped bodies 10 constituting the twin dummy bar 9 have a tail portion 10A.
are simply connected by a connecting rod 11, and there is a certain space between the two rod-like bodies 10.Moreover, both rod-like bodies 10 are heavy and their main bodies are made up of many links and can be bent. For some reason, the second
As shown in FIG. b, when the twin dummy bar 9 is held between the drive rolls 1A and pulled out in the direction of arrow A, each rod-like body passes through the center of gravity (G) from the contact point between the outer side edge 10C of both rod-like bodies 10 and the drive roll 1A. 1
A moment (M) is generated, which is the distance (l) to the center line of 0 multiplied by the weight (W), and both rod-like bodies 10 are bent into a "C" shape (inwardly toward each other) using the above contact point as a fulcrum. Put it away. In this way, both rod-shaped bodies 10
Once curved, it will not return to its original straight state because both rod-like bodies 10 are heavy. In this state, move the twin dummy bar 9 to arrow A.
When the head part 10B is pulled out in the direction shown in FIG.
is pressed against the inner surface of the central mold short piece 6A with a strong pressing force. Therefore, in order to protect the inner surface of the central mold short piece 6A, a protective plate 12 made of metal or synthetic resin is usually attached to the inner surface of the central mold short piece 6A.
However, in the state shown in Fig. 3,
Even if an attempt is made to remove the protective plate 12 and start continuous casting, the protective plate 12 is strongly pressed against the inner surface by the head portion 10B, so it is difficult to remove it, and the head portion is removed using a crowbar or the like. 10B in the direction away from the protective plate 12, and
The reality is that 2 is removed, and this work is extremely time-consuming. Furthermore, even if the protective plate 12 is removed and continuous casting is started, since the head portion 10B itself is tilted,
Among the side guide rolls 13 and 14, the side guide rolls 13 and 14 hit the one located below the central mold short piece 6A in order, and there is a risk that breakout may occur due to the vibration. Therefore, it is necessary to significantly reduce the drawing speed of the twin dummy bar 9 and carefully draw it out, which is one of the causes of reduced productivity.

Therefore, the present invention provides a twin dummy bar for continuous casting equipment that solves these problems.The main feature of the present invention is that the main body portions of both rod-shaped bodies constituting the twin dummy bar are connected by a large number of connecting links through pins. It is formed by a pair of left and right linear bodies connected in a straight line, and one end of these linear bodies and the other end are connected via a tail part and a head part with a space formed between both the linear bodies. , disposing a support link having a thickness greater than the thickness of the rod-shaped body at least near the tail portion within the space of the main body portion;
This support link is attached to the connecting link via the pin with both the front and back sides of the support link protruding outward from both the front and back sides of the rod-shaped body. According to this configuration, the twin dummy bar is held between the drive rolls. Even when pulled out, both rod-like bodies do not form a "V" shape and can be pulled out straight.

An embodiment of the present invention will be described below with reference to FIGS. 4 and 5. That is, 15 and 16 are linear bodies constituting the main body portions of both rod-shaped bodies 10,
A large number of connecting links 17 are linearly connected via pins, and a space 18 is formed between one end and the other end of these linear bodies 15 and 16. They are connected via a tail portion 10A and a head portion 10B. A plurality of (three in this embodiment) support links 19 are arranged at appropriate intervals along the longitudinal direction of the twin dummy bar 9 near the tail portion 10A in the space 18, and each support link 19 is connected to each of the above-mentioned connections. Link 17
are integrally connected with pins. Further, each of the support links 19 is shaped like a square bar, and its length is approximately equal to the length of the connection link 17 to which the support link 19 is attached, allowing relative rocking around the connection pin. The thickness of the support link 19 is set larger than the thickness of the connection link 17 as shown in FIG.
Both the front and back sides of the linear body 15 are formed into tapered surfaces 20 that become thicker toward the inner side of the linear body 15, and the above-mentioned thickness is formed so that both tapered surfaces 20 protrude from both the front and back surfaces of the linear bodies 15 and 16. setting and attachment to the connecting link 17 via a pin. Note that the inclination angle of this tapered surface 20 is so small that it is invisible to the naked eye.

According to this configuration, as shown in an exaggerated manner in FIG.
0 is in line contact with the drive roll 1A, and the linear body 1
Since the side edges of 5 and 16 also come into point contact with the drive roll 1A, in this state the drive roll 1A
Even if the twin dummy bar 9 is pulled out in the direction of the arrow A by rotating the twin dummy bar 9, the moment (M) is not generated in both rod-shaped bodies 10, so it will not fall down toward the center O, and the two bar-shaped bodies 10 will be pulled out from the mold 6 from above the dummy bar. It is pulled out in the direction of arrow A while remaining inserted, that is, in a straight line state. Therefore, the head portion 10B is not tilted and is not pressed against the inner surface of the central mold short piece 6A with a strong pressing force.

In the above embodiment, the support link 19 is provided only in the vicinity of the tail portion 10A of the space 18, but the support link 19 may be provided throughout the space 18. Further, in FIG. 5, the amount of deflection of the drive roll 1A is exaggerated, and in reality, the amount of deflection is about 0.1 mm.
and the support link 19 are in sufficient line contact, and there is no risk that both rod-like bodies 10 will form a "C" shape.

As described above, according to the twin dummy bar in the continuous casting equipment of the present invention, the main body portions of both rod-like bodies constituting the twin dummy bar are formed by a pair of left and right linear bodies in which a large number of connecting links are linearly connected via pins. One end and the other end of these linear bodies are connected via a tail portion and a head portion with a space formed between both linear bodies, and at least near the tail portion within the space of the main body portion, A support link having a thickness greater than the thickness of the rod-shaped body is provided, and the front and back surfaces of the support link are made to protrude outward from both the front and back surfaces of the rod-shaped body, and the support link is connected to the connecting link via the pin. Once installed, the twin dummy bars are inserted into the mold from above and clamped between the drive rolls, resulting in line contact between the drive rolls and the support links. Therefore, even if the drive roll is rotated and the twin dummy bar is pulled out in this state, both rod-like bodies will not bend down toward the center of the dummy bar, and both rod-like bodies will remain inserted in the mold, that is, in a straight line. It is removed in its original state. Therefore, although both rod-shaped bodies would normally form a "C" shape, it is possible to pull them out straight without this phenomenon occurring, and the head part of the twin dummy bar is tilted and inside the central mold short piece. Since the twin dummy bar is not pressed against the side surface with a strong pressing force and there is no risk of breakout even if the twin dummy bar is pulled out at a relatively high speed, productivity can be improved.

[Brief explanation of the drawing]

Fig. 1a is a schematic front view of the slab dummy bar inserted, Fig. 1b is a - arrow view of Fig. 1a, Fig. 2a is a schematic front view of the twin dummy bar inserted, and Fig. 2b is Fig. 2a. FIG. 3 is a schematic vertical sectional view showing the movement of the head portion of a general twin dummy bar. 4 and 5 show an embodiment of the present invention, with FIG. 4 being a front view and FIG. 5 being a view taken along the - arrow in FIG. 1... Guide roll group, 1A... Drive roll,
9... Twin dummy bar, 10... Rod-shaped body, 10A
...Tail part, 10B... Head part, 11... Connecting rod, 15, 16... Linear body, 17... Connecting link, 18... Space, 19... Support link (support body), 20... Tapered surface.

Claims (1)

[Scope of utility model registration request] The main body portions of both rod-like bodies constituting the twin dummy bar are formed by a pair of left and right linear bodies in which a large number of connecting links are linearly connected via pins, and the two ends of the linear bodies are connected between one end and the other end. A space is formed between the linear bodies and they are connected via a tail portion and a head portion, and a support link having a thickness greater than the thickness of the rod-shaped body is provided at least near the tail portion within the space of the main body portion. A twin dummy bar for continuous casting equipment, characterized in that the support link is attached to the connecting link via the pin with both the front and back sides of the support link protruding outward from both the front and back sides of the rod-shaped body.