JPH09220654A - Roller apron for continuous caster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To minimize mis-alignment mutually formed by divided support rolls of adjacent roll segments in a roller apron in a continuous caster constituting a cast slab passage by arranging plural roll segments provided with the divided support rolls divided in the width direction in the drawing out direction of the case slab. SOLUTION: Support frames 8 extending in the drawing out direction of the cast slab by dividing bearing parts 7 for supporting the divided support rolls 6 for each line of the drawing-out direction of the cast slab are formed into the integrally movable structure through advancing/retreating jacks 9. The advancing/retreating jacks 9 are worked in accordance with the worn degree with time of the divided rolls 6 developed by casting the cast slab, and the divided support rolls 6 supported by the bearing parts 7 are moved in the thickness direction of the cast slab 5 through the support frames 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller apron for a continuous casting machine equipped with divided support rolls that divide each support roll of a roller apron that constitutes a slab passage into at least two parts in the width direction.

[0002]

2. Description of the Related Art In continuous casting of steel, as shown in FIG. 6, molten steel 4 is poured from above a mold 1 whose upper and lower sides are open, cooled from the side surface of the mold 1 and partially solidified from its outer surface. Then, while being supported by the support roll 2 arranged below the mold 1, the casting is continuously performed by cooling with water spray from a spray nozzle (not shown). The support rolls 2 are usually incorporated in roll segments 3 each consisting of 5 to 10 pairs, and a large number of these roll segments 3 are arranged in the drawing direction of the slab 5 to form a slab passage.

The support roll 2 incorporated in the roll segment 3 generally uses a roll having a small diameter to shorten the roll pitch in order to minimize the bulging amount of the cast slab 5 between the rolls in the slab drawing direction. In addition, the structure is divided in the width direction and the number of bearings is increased to reduce the crown of the roll. For example, as shown in FIGS. 7 and 8, both ends of a divided support roll 6 obtained by dividing the support roll 2 into two in the width direction are supported by bearings 7. In this way, the split support rolls 6 are supported at their both ends by the bearings 7, but the bearings 7 located at the center are not arranged on the same line in the drawing direction of the casts 5. The roll non-supporting portions of No. 5 are dispersed. Therefore, the split support rolls 6 having different lengths are used, and the split support rolls 6 having long and short lengths are alternately arranged in the slab drawing direction.

By the way, the divided support rolls 6 arranged in the roll segment 3 are gradually abraded at a portion in contact with the slab 5 as shown by a dotted line A in FIG.
As shown in Figure 9, the casting amount is 600,000 tons, 1.2 million tons, 20
It will increase with time to 100,000 tons and will increase over time. If this wear amount x exceeds the limit, continuous casting will be hindered.
When the prescribed casting amount is reached, the casting amount is generally 100-
When it reaches 3 million tons, it is replaced with a new spare roll segment 3 by using the regular repair date of the continuous casting machine.

[0005]

However, it takes a lot of time to replace a large number of roll segments 3 at the same time, and the operation rate of the continuous casting machine is lowered. A method is adopted in which a part of the roll segments 3 whose wear amount x of the split support rolls 6 has approached the limit is sequentially replaced by using several regular repair days. However, in such a conventional method, a misalignment always occurs between the new roll segment 3 that has been exchanged and the adjacent roll segment 3 that has not been exchanged, as shown in FIG. 10, with respect to the reference alignment of the split support rolls 6. Will be done. When there is a significant difference in the amount of casting between the adjacent roll segments 3, the amount of misalignment in the portion of the split support roll 6 that contacts the center side of the slab 5 as shown by line A in FIG. There is a problem in that the diameter may exceed 1 mm, which hinders continuous casting.

The present invention provides a roller apron for a continuous casting machine capable of minimizing the amount of misalignment between roll segments which is inevitably generated when the roll segments are replaced due to the wear of the split support rolls as described above. The purpose is to do.

[0007]

According to the present invention for attaining the above object, a plurality of roll segments provided with split support rolls divided into at least two in the width direction are arranged in the slab drawing direction. In a roller apron of a continuous casting machine that forms a slab passage, the bearing portion that supports at least two split support rolls in the width direction is divided in the slab width direction so as to be movable in the slab thickness direction. , Moving the split support rolls in the thickness direction of the slab through the bearings according to the wear amount of the split support rolls caused by casting of the slab, and of the split support rolls that mutually occur with the adjacent roll segments. A roller apron for a continuous casting machine, which is configured to minimize the misalignment amount in the thickness direction of the cast slab.

The present invention according to claim 2 is characterized in that the bearing portion for supporting the divided support rolls is structured to be movable in the thickness direction of the slab by using a forward and backward movement device. This is the roller apron of the casting machine. Claim 3
According to the present invention described above, the bearing portion supporting the split support rolls is movable in the thickness direction of the slab integrally or in a plurality of sets via the support frame extending in the width direction of the slab by dividing the bearing portion in the width direction of the slab. The roller apron for a continuous casting machine according to claim 1 or 2, wherein the roller apron has a different structure.

The present invention as set forth in claim 4 is characterized in that the bearing portion for supporting the divided support rolls has a structure which can be independently moved in the thickness direction of the slab, and continuous casting according to claim 1 or 2. This is the Laura Apron of the machine.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION According to the present invention, since the bearing portion of the split support roll is structured to be movable in the thickness direction of the slab, the bearing portion of the slab is formed according to the wear amount of the split support roll over time. By moving in the thickness direction, it is possible to minimize the misalignment amount of the split support rolls that inevitably occurs between the roll segments when exchanging a part of the roll segments arranged in the continuous casting machine. become.

Embodiments of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows a slab 5 according to an embodiment of the present invention.
2 is a plan view showing a case where a divided support roll 6 divided into two in the width direction is incorporated into a roll segment 3. FIG. In this case, the bearing portion 7 supporting the divided support rolls 6 arranged in the drawing direction of the slab 5 is divided in the slab width direction and is supported via the support frame 8 extending in the slab drawing direction. ing. The support frame 8 supports the rows of bearings 7 located on both sides 2
Three support frames 8 and one support frame 8 that supports the row of bearings 7 located on the center side are arranged in a state of extending in parallel to the direction in which the slab is drawn out. The support frame 8 is provided with a forward / backward jack 9 as a forward / backward device on its back surface,
Each of the forward / backward jacks 9 is attached to the roll segment 3, and by operating the forward / backward jacks 9, the bearing portion 7 is moved forward / backward via the support frame 8.

As shown in FIG. 2, the three support frames 8 arranged in parallel are provided with a length corresponding to the length of the roll segment 3, and the forward and backward jacks provided above and below. By extending and contracting 9, the bearings 7 in each row are independently moved forward and backward through the support frame 8. Figure 9 and Figure
As shown in FIG. 10, the split support rolls 6 arranged in two in the width direction of the cast slab 5 have a larger wear amount x at the central portion as compared with the both end portions. This is because it is necessary to move the bearing portion 7 forward and backward independently for each row.

Next, the operation of the present invention will be described.
As shown in 10, if you replace it with a new roll segment 3 on a regular repair day and adjust the split support rolls 6 arranged on this new roll segment 3 to match the standard roll alignment, the casting amount will be 200 The adjacent roll segment 3 on the upstream side, which is 10,000 tons, and the casting amount on the downstream side are
Misalignment occurs between the divided support rolls 6 arranged on the adjacent roll segments 3 of 1.2 million tons. That is, when observing the misalignment amount with respect to the reference roll alignment for three lines of the central support A line, the intermediate side B line, and the end side C line of the split support roll 6, the central side A line shows a new roll segment 3. The split support rolls 6 have a misroll alignment amount of about 1.5 mm between the upstream side adjacent roll segment 3 and the split support rolls between the new roll segment 3 and the downstream side adjacent roll segment 3. 6 It can be seen that there is a misroll alignment amount of about 1.0 mm.

Further, in the B line on the intermediate side, the adjacent roll segments 3 on the upstream side and the downstream side of the new roll segment 3 have misroll alignment amounts of 0.5 to 1.0 mm between the divided support rolls 6 and the end portions thereof. In the C line on the side, the amount of wear of the split support rolls 6 is small, and the misroll alignment amount between the split support rolls 6 of both the upstream and downstream adjacent roll segments 3 is close to zero and is almost on the reference roll alignment. I understand.

According to the present invention, the amount of misalignment that occurs between the split support rolls 6 arranged on the new roll segment 3 and the split support rolls 6 arranged on the upstream and downstream adjacent roll segments 3 is described. The purpose is to minimize. In order to achieve this object, in the present invention, as shown in FIGS. 1 and 2, three supports arranged in parallel are divided into adjacent roll segments 3 arranged on the upstream side and the downstream side of the new roll segment 3. By operating the frame 8 to move the forward / backward jacks 9, the misalignment between the split support rolls 6 is minimized. In the case of FIG. 10, since the misalignment amount is large on the A line on the center side, the forward / backward jack 9 corresponding to the support frame 8 located in the central portion is operated to the forward side,
The split support roll 6 is moved forward via the bearing 7 on the center side in accordance with the amount of wear in the roll width direction. As a result, the misalignment amount generated between the divided support rolls 6 is minimized to less than 1.0 mm, and the misalignment amount is adjusted to approach the reference roll alignment.

In FIGS. 1 and 2, the three support frames 8 extending in parallel with the direction in which the slab is drawn are made to have a length corresponding to the length of the roll segment 3 and the divided support rolls 6 are provided.
The case where the support frames 8 are integrally moved according to the respective arrangements has been described. However, as shown in FIG. The support frame 8 and the support frame 8 on the lower side may be provided. In this case, the upstream and downstream roll segments 3
It is possible to make finer adjustments to misalignment in response to and. Further, as shown in FIG. 4, it is possible to divide the support frame 8 in the roll segment 3 for each bearing portion 7 and adjust each bearing portion 7 independently. Of course, the present invention can be applied to a multi-division support roll having three or more divisions.

FIG. 5 shows the new roll segment and casting amount.
The amount of roll misalignment between the split support rolls generated between the adjacent roll segments of 2 million tons is shown in comparison between the case where the present invention is carried out and the conventional case. According to the present invention, it can be seen that what has been reduced to 0.5 mm.

[0018]

As described above, according to the present invention, the bearing portion for supporting the split support rolls divided into at least two in the width direction is divided in the width direction of the slab and is movable in the thickness direction of the slab. With the structure, the split support rolls are moved in the thickness direction of the slab via the bearings according to the wear amount of the split support rolls caused by casting of the slabs over time, so that the splits that occur between adjacent roll segments occur. The misalignment amount of the support roll can be minimized.

As a result, it becomes possible to extend the life until the roll segment is replaced to three times or more that of the conventional one. Also, since the internal strain of the slab due to roll misalignment can be reduced to 1/3 or less, the casting speed at the time of producing slabs for high carbon steel with high internal cracking susceptibility can be dramatically increased. It is possible to improve productivity of continuous casting.

[Brief description of drawings]

FIG. 1 is a plan view showing a split support roll according to the present invention.

FIG. 2 is a side view showing a split support roll according to the present invention.

FIG. 3 is a side view showing another split support roll according to the present invention.

FIG. 4 is a side view showing still another split support roll according to the present invention.

FIG. 5 is a bar graph showing a comparison of misalignment amounts of a conventional support roll and a split support roll of the present invention.

FIG. 6 is a side view schematically showing a conventional bending type continuous casting machine in which roll segments are arranged.

FIG. 7 is a front view showing a conventional split support roll.

FIG. 8 is a plan view showing a conventional split support roll.

FIG. 9 is an explanatory diagram showing a roll wear amount (x) in the width direction of the divided support rolls in relation to a casting amount.

FIG. 10 is an explanatory diagram showing a misroll alignment amount at a specific position in a width direction of divided support rolls in which adjacent roll segments are arranged.

[Explanation of symbols]

 1 mold 2 support roll 3 roll segment 4 molten steel 5 cast slab 6 split support roll 7 bearing 8 support frame 9 forward / backward jack

Claims (4)

[Claims] 1. A roller apron for a continuous casting machine in which a plurality of roll segments provided with divided support rolls divided into at least two in the width direction are arranged in the slab drawing direction to form a slab passage, and at least 2 in the width direction of the roller apron. The bearing part that supports the divided support rolls is divided into the width direction of the slab to make the structure movable in the thickness direction of the slab. It is characterized in that the split support roll is moved in the thickness direction of the slab through the slab, and the slab thickness direction misalignment amount of the split support roll that is mutually generated with the adjacent roll segment is minimized. Roller apron for continuous casting machine. 2. A roller apron for a continuous casting machine according to claim 1, wherein the bearing portion for supporting the split support roll is structured to be movable in the thickness direction of the slab by using a forward / backward movement device. 3. A bearing portion supporting the divided support rolls is divided in the width direction of the slab and is movable in the thickness direction of the slab integrally or in a plurality of sets via a support frame extending in the drawing direction. The roller apron for a continuous casting machine according to claim 1 or 2, which has a structure. 4. The roller apron for a continuous casting machine according to claim 1, wherein the bearing portions supporting the split support rolls are structured to be independently movable in the thickness direction of the slab.