JP2017202505A - Cut length control method of cast slab and cut length control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cut length control method of a cast slab which suppresses the lowering of a yield, and can reduce a variation of the actual weight of the cast slab with respect to the required weight of the cast slab, and a cut length control device.SOLUTION: This cut length control method of a cast slab acquires information related to a cooling water amount with respect to a casting strand in continuous casting equipment (step S1), calculates the weight of the casting strand per unit length corresponding to the acquired cooling water amount by using data indicating a relationship between the cooling water amount and an actual value of the weight of the casting strand per unit length (step S2), and corrects a cut length of the cast slab by using the calculated weight (step S3). By this constitution, the lowering of a yield can be suppressed, and a variation of the actual weight of the cast slab with respect to the required weight of the cast slab can be reduced.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a cutting length control method and a cutting length control device for a cast slab.

  In general, the cutting length of a cast slab obtained by cutting a cast strand cast in a continuous casting facility is determined according to the required weight of the cast slab, but the weight per unit length of the cast strand varies. There is. For this reason, conventionally, the cutting length of the cast slab has been adjusted to a length in which an operator has added a margin in consideration of variation in weight per unit length of the cast strand according to a rule of thumb. In addition, as a general casting strand cutting device, for example, there is one described in Patent Document 1.

JP 2002-143996 A

  However, when the operator adjusts the cutting length of the cast slab based on an empirical rule, the additional weight ratio corresponding to the added margin (= (actual weight of cast slab−required weight of cast slab) / cast slab (Required weight) increases and yield decreases. Further, the variation in the actual weight of the cast slab with respect to the required weight of the cast slab increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a cast slab capable of suppressing a decrease in yield and reducing variation in the actual weight of the cast slab with respect to the required weight of the cast slab. To provide a cutting length control method and a cutting length control device.

  The method for controlling the cutting length of a cast slab according to the present invention is such that the weight of the cast slab obtained by cutting a cast strand cast in a continuous casting facility is matched with a target weight obtained by adding a margin to a required weight. A method for controlling a cutting length of a cast slab for controlling a cutting length of a slab, the acquisition step of acquiring information on a cooling water amount for the casting strand in the continuous casting equipment, a cooling water amount and a unit length of the casting strand Using the data indicating the relationship with the actual value of the weight per unit, calculate the weight per unit length of the cast strand corresponding to the amount of cooling water acquired in the acquisition step, using the calculated weight A correction step for correcting the cutting length of the casting slab, and a cutting length corrected in the correction step A cutting step of cutting the serial cast slab, characterized in that it comprises a.

  The apparatus for controlling the cutting length of a cast slab according to the present invention is such that the weight of the cast slab obtained by cutting a cast strand cast in a continuous casting facility matches the target weight with a margin added to the required weight. A casting slab cutting length control device for controlling a cutting length of a slab, the acquisition means for acquiring information on a cooling water amount for the casting strand in the continuous casting equipment, a cooling water amount and a unit length of the casting strand Using the data indicating the relationship with the actual value of the weight per unit of weight, calculate the weight per unit length of the cast strand corresponding to the amount of cooling water acquired by the acquisition means, using the calculated weight Correction means for correcting the cutting length of the cast slab, and the casting slab with the cutting length corrected by the correction means And cutting means for cross, characterized in that it comprises a.

  According to the cutting length control method and the cutting length control device of the cast slab according to the present invention, it is possible to suppress a decrease in yield and to reduce the variation in the actual weight of the cast slab with respect to the required weight of the cast slab.

FIG. 1 is a schematic diagram showing the configuration of a continuous casting facility to which a casting slab cutting length control method according to an embodiment of the present invention is applied. FIG. 2 is a flowchart showing a flow of a cast slab cutting length control method according to an embodiment of the present invention. FIG. 3 is a diagram showing a histogram of the actual values of the added weight ratio of the cast slab when the cutting length control process according to the embodiment of the present invention is applied. FIG. 4 is a diagram showing a histogram of the actual values of the added weight ratio of the cast slab when the operator determines the cutting length of the cast slab based on an empirical rule.

  Hereinafter, a method for controlling a cutting length of a cast slab, which is an embodiment of the present invention, will be described with reference to the drawings.

[Construction of continuous casting equipment]
First, with reference to FIG. 1, the structure of the continuous casting equipment to which the cutting length control method of the casting slab which is one Embodiment of this invention is applied is demonstrated.

  FIG. 1 is a schematic diagram showing the configuration of a continuous casting facility to which a casting slab cutting length control method according to an embodiment of the present invention is applied. As shown in FIG. 1, in the continuous casting equipment 1 to which the method for controlling the cutting length of a cast slab according to an embodiment of the present invention is applied, pig iron in the ladle 2 is tundished 4 through a refractory nozzle 3. The pig iron in the tundish 4 is supplied to the mold 6 through a refractory nozzle called an immersion nozzle 5. The mold 6 is vibrated so as not to be seized by a vibration device (not shown), and the cast strand ST pulled out from the mold 6 is gradually drawn downward while being supported by the support roll 7.

  In the vicinity of the support roll 7, a secondary cooling zone including a plurality of individually controllable cooling zones Z1 to Z17 is configured. In the secondary cooling zone, the casting strand ST is cooled from the outer surface by spraying cooling water on the casting strand ST in a mist form from the spray nozzle. The cast strand ST is cut into the cast slab S by the torch 8 after passing through the light pressure belt as necessary. The torch 8 is moved in the casting direction by the torch control device 9 according to the casting speed of the casting strand ST. In addition, the code | symbol 10 is a weighing machine which measures the weight of the casting slab S in FIG. The torch control device 9 controls the cutting length of the cast slab S by executing a method for controlling the cutting length of the cast slab which is an embodiment of the present invention described later.

[Cut length control method of cast slab]
The main reason why the actual weight of the cast slab S varies with respect to the required weight is that the amount of heat shrinkage of the cast strand ST during cutting is unknown. That is, if the amount of heat shrinkage of the cast strand ST at the cutting position by the torch 8 is large, the weight per unit length of the cast strand ST becomes heavy. Conversely, if the amount of heat shrinkage is small, the weight per unit length of the cast strand ST is small. Becomes lighter. In other words, the lower the average temperature at the cutting position by the torch 8, that is, the smaller the amount of heat shrinkage at the cutting position by the torch 8, the heavier the unit length of the cast strand ST becomes.

  Therefore, the method for controlling the cutting length of the cast slab according to one embodiment of the present invention includes the amount of cooling water for the casting strand ST in the secondary cooling zone and the weight per unit length of the casting strand ST at the cutting position of the casting strand ST. The cutting length of the casting slab S is controlled using data indicating the relationship. Hereinafter, with reference to FIG. 2, the cutting length control method of the casting slab which is one Embodiment of this invention is demonstrated.

  FIG. 2 is a flowchart showing a flow of a cast slab cutting length control method according to an embodiment of the present invention. The flowchart shown in FIG. 2 starts at the timing when casting of the cast strand ST is started in the continuous casting equipment 1, and the cutting length control process proceeds to the process of step S1.

  In the process of step S1, the torch control device 9 acquires information on the cooling water amount for the casting strand ST in the secondary cooling zone by communicating with a control device such as a process computer that controls the operation of the continuous casting facility 1. Thereby, the process of step S1 is completed and the cutting length control process proceeds to the process of step S2.

  In the process of step S2, the torch control device 9 is a data indicating the relationship between the cooling water amount for the cast strand ST in the secondary cooling zone and the actual value of the weight per unit length of the cast strand ST at the cutting position of the cast strand ST. Is used to calculate the weight of the cast strand ST at the cutting position of the cast strand ST corresponding to the amount of cooling water acquired in step S1. Thereby, the process of step S2 is completed, and the cutting length control process proceeds to the process of step S3.

  In the process of step S3, the torch control device 9 uses the weight per unit length of the cast strand ST at the cutting position of the cast strand ST calculated in the process of step S2 to realize a predetermined additional weight ratio. The cutting length of the casting slab S is determined. Thereby, the process of step S3 is completed and a series of cutting length control processes are complete | finished. Thereafter, the torch control device 9 cuts the cast slab S according to the cutting length S determined by controlling the torch 8.

  As is clear from the above description, in the cutting length control process according to an embodiment of the present invention, the torch control device 9 acquires information on the cooling water amount for the casting strand ST, and the unit of the cooling water amount and the casting strand ST is obtained. The weight per unit length of the cast strand ST corresponding to the acquired amount of cooling water is calculated using data indicating the relationship with the actual value of the weight per length, and the casting slab S is used using the calculated weight. Since the cutting length is corrected, it is possible to suppress a decrease in yield and to reduce the variation in the actual weight of the cast slab with respect to the required weight of the cast slab S.

  FIG. 3 is a diagram showing a histogram of the actual values of the added weight ratio of the cast slab when the cutting length control process according to the embodiment of the present invention is applied. FIG. 4 is a diagram showing a histogram of the actual values of the added weight ratio of the cast slab when the operator determines the cutting length of the cast slab based on an empirical rule. In this example, the target value of the additional weight ratio was 1.7%.

  As shown in FIG. 4, when the operator determined the cutting length of the cast slab based on an empirical rule, the average value of the actual value of the additional weight ratio was 2.40%. On the other hand, as shown in FIG. 3, the average value of the actual value of the additional weight ratio of the cast slab when the cutting length control process according to the embodiment of the present invention was applied was 1.90%. . From this, it was confirmed that according to the cutting length control process which is one embodiment of the present invention, the additional weight ratio can be reduced and the yield can be improved.

  Furthermore, as shown in FIG. 4, when the operator determined the cutting length of the cast slab based on an empirical rule, the standard deviation of the actual value of the added weight ratio was 0.73%. On the other hand, as shown in FIG. 3, the standard deviation of the actual value of the additional weight ratio of the cast slab when the cutting length control process according to the embodiment of the present invention is applied was 0.64%. . From this, it was confirmed that the variation in the actual weight of the cast slab with respect to the required weight of the cast slab can be reduced according to the cutting length control process which is an embodiment of the present invention.

  As mentioned above, although the embodiment to which the invention made by the present inventor is applied has been described, the present invention is not limited by the description and the drawings constituting a part of the disclosure of the present invention according to the present embodiment. What was comprised combining the component suitably is also contained in this invention. That is, other embodiments, examples, operational techniques, and the like made by those skilled in the art based on the present embodiment are all included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Continuous casting equipment 2 Ladle 3 Refractory nozzle 4 Tundish 5 Immersion nozzle 6 Mold 7 Support roll 8 Torch 9 Torch control device 10 Weighing machine S Casting slab ST Casting strand

Claims (2)

The cutting length of the casting slab for controlling the cutting length of the casting slab so that the weight of the casting slab obtained by cutting the cast strand cast in the continuous casting equipment matches the target weight with a margin added to the required weight. A control method,
An acquisition step of acquiring information related to the amount of cooling water for the casting strand in the continuous casting facility;
Using data indicating the relationship between the amount of cooling water and the actual value of the weight per unit length of the cast strand, the weight per unit length of the cast strand corresponding to the amount of cooling water acquired in the acquisition step is calculated. A correction step of calculating and correcting the cutting length of the cast slab using the calculated weight;
A cutting step of cutting the cast slab with the cutting length corrected in the correcting step;
A method for controlling the cutting length of a cast slab, comprising: The cutting length of the casting slab for controlling the cutting length of the casting slab so that the weight of the casting slab obtained by cutting the cast strand cast in the continuous casting equipment matches the target weight obtained by adding a margin to the required weight. A control device,
Obtaining means for obtaining information on the amount of cooling water for the casting strand in the continuous casting facility;
Using data indicating the relationship between the amount of cooling water and the actual value of the weight per unit length of the cast strand, the weight per unit length of the cast strand corresponding to the amount of cooling water acquired by the acquisition means is calculated. Calculating means for correcting the cutting length of the cast slab using the calculated weight;
Cutting means for cutting the cast slab with the cutting length corrected by the correcting means;
A cutting length control device for a cast slab, comprising:

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