JP3269439B2 - Method and apparatus for producing continuous cast slab - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a plurality of cast pieces by cutting a strand continuously drawn from a mold of a continuous casting machine so as to have a plurality of predetermined target values. It relates to an apparatus used for implementation.

[0002]

2. Description of the Related Art Conventionally, in a continuous casting machine, a continuously cast strand has been cut as follows to produce a plurality of cast pieces. The molten metal flows into the tundish from the ladle,
Then, the molten metal which has been temporarily stored and has a stable flow is injected from a nozzle connected to the tundish into a cylindrical mold in which a water passage is embedded. While the strand having a solidified shell formed around it by contact with the inner wall of the mold is continuously pulled out from the mold, water is sprayed on the surface of the strand and solidification proceeds to the center.

On the other hand, the length of each slab to be produced by one charge of molten metal flowing from a ladle into a tundish is adjusted so as to meet a plurality of requirements from a subsequent rolling process. , The opening area of the mold, the heat shrinkage function, and the like. Each time the strand solidified to the center is drawn out by the above-described length, the strand is cut by a cutting machine arranged at a predetermined position in the drawing direction to obtain a plurality of cast pieces having a required length.

[0004]

However, according to the conventional method, when a trouble occurs in the cutting machine and a slab having a predetermined length cannot be obtained, or the slab is interrupted by an operator. If the length of the slab is changed and the slab of the predetermined length cannot be obtained, the yield decreases and the slab of the length is rolled at the timing when the casting of one charge is completed. Since it cannot be supplied to the process, the schedule of the rolling process has to be changed, and there has been a problem that the work of changing the schedule requires much labor. In addition, there is a possibility that the completion time of a product relating to a slab having a predetermined size is delayed and a delivery date is delayed.

[0005] The present invention has been made in view of the above circumstances, and it is an object of the present invention every time a strand is cut to obtain a slab, the actual value of the physical quantity of the slab and the selected target value are determined. Compare and determine whether or not a slab of the selected target value has been obtained, and if it is determined that it has not been obtained, each of the other target values and the actual value are compared, and the casting of the target value is determined. It is determined whether or not there is another target value with which a piece is obtained, and if it exists, trouble occurs in the cutting machine by excluding the other target values from the selection target, and the slab Even if the target value of is changed, it is possible to obtain a slab of a predetermined length dimension, a continuous cast slab that can minimize the decrease in the yield and the influence on the subsequent process To provide a method for producing the same and an apparatus for use in the method In the door.

[0006]

According to a first aspect of the present invention, there is provided a method for manufacturing a continuous cast slab, wherein a strand continuously drawn from a mold is set to a target value sequentially selected from a plurality of predetermined target values. By repeatedly cutting, in a method of manufacturing a plurality of cast pieces, each time the strand is cut to obtain a cast piece, a physical quantity according to the target value of the cast piece is measured, and the obtained actual value and selection are performed. And compare the target value
Based on the comparison result, it is determined whether or not the slab of the selected target value is obtained, and when it is determined that it is obtained,
If the selected target value is excluded from the selection target and it is determined that it has not been obtained, the selected target value is again selected, and the other target values are compared with the actual values, respectively. Based on the result, it is determined whether there is another target value that a slab of the target value is obtained, and if it exists, the other target values are excluded from selection. I do.

[0007] A continuous cast slab manufacturing apparatus according to a second aspect of the present invention cuts a strand continuously drawn from a mold so as to have a target value sequentially selected from a plurality of predetermined target values from the tip thereof. By repeating the above, in the apparatus for manufacturing a plurality of slabs, means for measuring a physical quantity according to the target value of the slab obtained by cutting the strand,
Means for comparing the obtained actual value with the selected target value;
A means for determining whether or not a slab having the selected target value is obtained based on the comparison result, and a means for excluding the selected target value from the selection target when determining that the slab is obtained, If it is determined that it has not been obtained, there are means for comparing the other target values and the actual values, respectively, and based on the result of the comparison, there are other target values indicating that a slab of the target value has been obtained. It is characterized by comprising means for judging whether or not, and when it exists, means for excluding other target values from the selection.

FIG. 4 is an explanatory view for explaining the principle of the present invention. In FIG. 4, reference numeral 10 denotes a cylindrical mold. As shown in FIG. 4A, the strand S is pulled out of the mold 10,
At a predetermined position in the longitudinal direction of the strand S, a cutting machine 5 for cutting the strand S by a torch in a direction orthogonal to the longitudinal direction is arranged. Now from strand S 6
m, 6m, 5m, 6m, 7m, 8m slabs A, B, C,
It is assumed that an initial plan for manufacturing D, E, and F in this order has been created. Are assigned to the strand S in order from the top according to the target length of each of the slabs A, B,... When the position is reached, the cutting machine 5 cuts the strand S.

However, as shown in FIG.
When the head of the slab is pulled 5 m downstream from the position of the cutting machine 5 and a trouble occurs, and the strand S is cut by the cutting machine 5 to obtain the slab T, the target length of the slab A Is determined not to have been obtained. on the other hand,
If the actual length obtained by measuring the slab T is within the target length of the slab A ± the predetermined length, it is determined that the slab T having the target length of the slab A has been obtained.

When the slab T of the target length of the slab A is not obtained, the target lengths of the slabs B, C, D, E and F other than the slab A and the actual length of the slab T are respectively set. By comparison, it is determined whether or not the actual length of the slab T is within the target length ± the predetermined length. Since the actual length of the slab T is 5 m,
It matches the target length of the slab C. Therefore, as shown in FIG. 4C, the slab C is assigned to the slab T and the strand S
, The slab A is allocated to the area 6 m from the head of the strand S, and the areas of the slabs B, D, E, and F are subsequently allocated according to the target length. .

Then, as shown in FIG.
Is pulled out 6 m downstream from the position of the cutting machine 5, the strand S is cut by the cutting machine 5.
Then, the actual length of the obtained slab is measured, and when the actual length is the target length of the slab A, it is determined that the slab of the target length of the slab A has been obtained, and the strand is determined. The area of the slab A assigned to S is deleted. As a result, even if a trouble occurs in the cutting machine and the target value of the slab is changed,
It is possible to obtain a slab of a required actual value, and it is possible to suppress a decrease in yield and an influence on a subsequent process as much as possible.

[0012]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an apparatus according to the present invention, in which 10 is a cylindrical mold. The mold 10 is such that the molten metal is injected from one end thereof, and the molten metal in the mold 10 is
The strand S is cooled by contact with the wall surface of the mold 10 and has a solidified shell formed around the strand S. The strand S is continuously drawn in the arrow direction from the other end of the mold 10.

At an appropriate position in the longitudinal direction of the strand S,
First rotating head for measuring the length of the strand S
11 is in contact with the strand S, and the first rotary head 11
Is given to the first length calculator 1. The first length calculator 1 calculates the number of rotations of the first rotary head 11 and a distance between the first rotary head 11 and a cutting start position described later.
The length from the head of the strand S to the cutting start position is calculated and given to the control computer 3 for controlling the cutting of the strand S based on a preset cutting plan.
A cutting start position is set slightly downstream of the first rotary head 11, and a cutting machine that cuts the strand S by a cutting torch in a direction orthogonal to the longitudinal direction to generate a slab T is provided at the cutting start position. 5 is disposed so as to be movable in the longitudinal direction of the strand S. The cutting operation of the cutting machine 5 is controlled by the cutting machine control device 4.

The slab T produced by cutting the strand S by the cutting machine 5 is carried out in the direction of a white arrow by carry-out rollers 8, 8,. A second rotary head 21 for measuring the length of the slab T is disposed on the entry side of the carry-out rollers 8, 8,. The rotation speed is given to the second length calculator 2. Second length calculator 2
Calculates the length of the slab T based on the number of rotations of the second rotary head 21 and supplies it to the control computer 3 described above.
The CPU 31 of the control computer 3 issues a cutting command based on the length of the strand S and the length of the slab T given from the first length calculator 1 and the second length calculator 2 as follows. And generates it at an appropriate timing.
Give to.

When a cutting command is given, the cutting machine control device 4 ignites the cutting torch of the cutting machine 5 to move it in a direction orthogonal to the longitudinal direction of the strand S, and pulls out the cutting machine 5 from the strand S. When the strand S is cut downstream at the same speed as the speed, the cutting torch is extinguished and the cutting machine 5 is returned to the upstream cutting start position.

FIGS. 2 and 3 are flowcharts showing a procedure for generating a cutting command by the CPU 31 of the control computer 3 shown in FIG. The CPU 31 is provided with a cutting plan such as a target length of a plurality of slabs to be manufactured and a cutting order thereof from a host computer (not shown). The memory
32 and stored therein (steps S1 and S2). C
The PU 31 reads, from the cutting plan stored in the memory 32, the target length of the slab having a young cutting order among the slabs not yet cut (step S3), and is provided from the first length calculator 1. It waits until the length reaches the read target length (step S4).

When the CPU 31 determines that the length given from the first length calculator 1 has reached the read target length, it gives a cutting start command to the cutting machine control device 4 (step S5). The cutting machine controller 4 controls the cutting machine 5 to cut the strand S. The CPU 31 waits until the actual length of the slab T is given from the second length calculator 2 (Step S).
6) When given, the actual length is compared with the target length read as described above (step S7), and based on the comparison result, whether the actual length is within the range of the target length ± α. It is determined whether or not it is (step S8). The CPU 31
If it is determined that the actual length is within the range of the target length ± α, the process proceeds to step S11, and the information that the slab corresponding to the target length has been cut is stored in the cutting plan stored in the memory 32. Write.

On the other hand, if it is determined in step S8 that the actual length is not within the range of the target length ± α, the CPU 31 compares the actual length with the target length of the uncut slab included in the cutting plan in the memory 32. Each is compared (step S9), and based on the result, it is determined whether or not there is an uncut slab whose actual length falls within the range of the target length ± α (step S9).
Ten). When determining that the slab is present, the CPU 31 writes information that the slab has been cut into the cutting plan stored in the memory 32 (step S11). On the other hand, when it is determined that there is no uncut slab having the actual length within the range of the target length ± α, the CPU 31 does not change the information of the cutting plan, that is, the target selected as described above. The slab corresponding to the length is left uncut, and step S12 is performed.
Move to Thereby, the cut slab T is made surplus.

The CPU 31 determines whether all target lengths of uncut slabs have been read from the cutting plan stored in the memory 32 (step S12). The operations from S3 to S12 are repeated.

In the present embodiment, the slab is cut to have a plurality of lengths set in advance. However, the present invention is not limited to this, and the quality set in advance is considered in addition to the length. It goes without saying that it is possible to do so. In the present embodiment, the case where one strand is cast is described. However, the present invention is not limited to this, and is also applicable to the case where a plurality of molds are connected to a tundish to cast a plurality of strands. It goes without saying that it can be done.

[0021]

As described in detail above, in the present invention,
Even if a trouble occurs in the cutting machine and the target value of the slab is changed, it is possible to obtain a slab of the required actual value,
The present invention has excellent effects such as a decrease in yield and an influence on a post-process can be suppressed as much as possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an apparatus according to the present invention.

FIG. 2 is a flowchart showing a procedure for generating a disconnection command by a CPU of the control computer shown in FIG. 1;

FIG. 3 is a flowchart showing a procedure for generating a disconnection command by a CPU of the control computer shown in FIG. 1;

FIG. 4 is an explanatory diagram illustrating the principle of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st length calculator 2 2nd length calculator 3 Control computer 4 Cutting machine control device 5 Cutting machine 10 Mold 31 CPU 32 Memory S Strand T Cast piece

Continuation of the front page (56) References JP-A-63-220958 (JP, A) JP-A-62-212047 (JP, A) JP-A-56-95456 (JP, A) JP-A-58-159955 (JP, A) JP-A-3-27853 (JP, A) JP-A-60-82252 (JP, A) JP-A-10-249504 (JP, A) JP-A-61-60250 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) B22D 11/16 B22D 11/126

Claims (2)

(57) [Claims] 1. A method of producing a plurality of cast pieces by repeatedly cutting a strand continuously drawn from a mold so as to have a target value selected sequentially from a plurality of predetermined target values, Each time the strand is cut to obtain a slab, the physical quantity related to the target value of the slab is measured, the obtained actual value is compared with the selected target value, and based on the comparison result, the selected target is selected. It is determined whether or not the slab of the value has been obtained.If it is determined that the slab has been obtained, the selected target value is excluded from the selection targets.If it is determined that it has not been obtained, the selected target value is changed. While making the selection target again, each of the other target values is compared with the actual value, and based on the comparison result, it is determined whether or not there is another target value with which the slab of the target value is obtained. Judge and, if it exists, its Method for producing a continuously cast slab, characterized in that to exclude the target value from the selected target. 2. A plurality of slabs is manufactured by repeatedly cutting a strand continuously drawn from a mold from its tip to a target value sequentially selected from a plurality of predetermined target values. In the apparatus, means for measuring the physical quantity according to the target value of the slab obtained by cutting the strand, and means for comparing the obtained actual value and the selected target value, based on the comparison result, A means for determining whether or not a slab of the selected target value has been obtained, and a means for excluding the selected target value from the selection target when determining that it has been obtained, and a determination that the slab has not been obtained. In this case, means for comparing each of the other target values with the actual value, and means for judging, based on the comparison result, whether or not there is another target value indicating that a slab of the target value is obtained. And if it exists Other continuous casting slab of a manufacturing apparatus characterized by comprising a way to exclude the target value from the selected target.