KR101443351B1 - Apparatus and method for diagnosing crack of continuous casting slab - Google Patents

Abstract

Disclosed in the present invention are an apparatus and a method for diagnosing a crack on a slab. The apparatus for diagnosing a crack on a slab comprise: multiple temperature sensors which are installed in a short side of a mold, and measure the surface temperature of the short side of a continuously casting slab; a setting unit which calculates an average of the surface temperature measured for a preset time in order to set a reference temperature; a calculating unit which calculates a deviation between the surface temperature of the short side of the slab measured by the temperature sensor after the preset time and the reference temperature; and a determining unit which compares the temperature deviation with a set value, and determines the occurrence of a horizontal crack on the short side of the slab.

Description

[0001] APPARATUS AND METHOD FOR DIAGNOSING CRACK OF CONTINUOUS CASTING SLAB [0002]

The present invention relates to a slab crack diagnosis apparatus and method.

The refined molten steel in the steelmaking process is transferred to a ladle in the steelmaking process and transferred from the ladle to a tundish, which is an intermediate storage device, and then supplied to one or more molds.

In this case, the molten steel is cooled while passing through the continuous casting equipment and solidified into a solid slab. In a continuous casting facility, molten steel is first passed through a water-cooled mold to form a solidified shell. After passing through a strand, the molten steel is completely solidified through cooling water injection and becomes a solid slab.

When the tundish is filled with all the molten steel in the injection ladle and then replaced with another ladle (continuous casting operation), the molten steel is continuously supplied to the mold, so the slab is produced without interruption.

The background art of the present invention is disclosed in Korean Patent Laid-Open Publication No. 10-2013-0009154 (2013.01.23, performance facility).

Embodiments of the present invention provide a slab crack diagnosis apparatus and method for judging whether or not a longitudinal crack of a slab produced in a continuous casting process occurs.

According to an aspect of the present invention, there is provided a temperature control apparatus comprising: a plurality of temperature sensors installed at a short side of a mold for measuring a temperature of a short side surface of a slab continuously cast; A setting unit for setting a reference temperature by calculating the surface temperature average measured for a predetermined time; A calculating unit for calculating a temperature deviation between the reference temperature and the short side surface temperature of the slab measured by the temperature sensor after the predetermined time; And a determiner for comparing the temperature deviation with a set value to determine whether a crack in the width direction of the slab short side portion is generated.

Wherein the temperature sensor comprises: a center sensor for measuring a surface temperature at the center of a short side of the slab; And an edge sensor for measuring a surface temperature of a short side edge of the slab.

Wherein the setting unit sets the center reference temperature using the center sensor and the edge reference temperature using the edge sensor, and the calculating unit calculates the center temperature deviation based on the center reference temperature and the edge temperature deviation based on the edge reference temperature, respectively And the judging unit can judge that a crack in the width direction of the short side of the slab is generated when both the center temperature deviation and the edge temperature deviation are equal to or more than the set value.

The edge sensor may be installed at a position spaced apart from the edge of the mold by 50 mm or less.

According to another aspect of the present invention, there is provided a method for measuring a surface temperature of a slab continuously cast by a temperature sensor installed at a short side of a mold, Calculating an average of the surface temperatures measured during the predetermined time to set a reference temperature; Calculating a temperature difference between the reference temperature and the short side surface temperature of the slab measured by the temperature sensor after the predetermined time; And comparing the temperature deviation with a set value to determine whether a widthwise crack of the slab short side portion is generated.

Wherein the temperature sensor comprises: a center sensor for measuring a surface temperature at the center of a short side of the slab; And an edge sensor for measuring a surface temperature of a short side edge of the slab,

The step of setting the reference temperature may include setting a center reference temperature according to the surface temperature measured by the center sensor and an edge reference temperature according to the surface temperature measured by the edge sensor, .

The step of calculating the temperature deviation may include calculating a center temperature deviation according to the center reference temperature and an edge temperature deviation according to the edge reference temperature, respectively.

The step of judging whether or not cracks are generated may determine that a widthwise crack at the short side of the slab is generated when both the center temperature deviation and the edge temperature deviation are equal to or more than a set value.

According to embodiments of the present invention, quality improvement can be achieved by detecting and selectively scarring the slab where short side widthwise cracks have occurred.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a slab crack diagnosis apparatus according to an embodiment of the present invention. FIG.
2 is a block diagram showing a configuration of a slab crack diagnosis apparatus according to an embodiment of the present invention;
3 is a view showing an analysis of a crack index of a crack diagnosis apparatus of a slab according to an embodiment of the present invention.
4 is a flowchart illustrating a method of diagnosing a crack in a slab according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a slab crack diagnosis apparatus and method according to the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals refer to like or corresponding components, A duplicate description will be omitted.

FIG. 1 is a block diagram of a slab crack diagnosis apparatus according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a configuration of a slab crack diagnosis apparatus according to an embodiment of the present invention.

1 and 2, a slab crack diagnosis apparatus 100 according to the present invention may include a temperature sensor 110, a setting unit 120, a calculating unit 130, and a determining unit 140 . In addition, the temperature sensor 110 may include a center sensor 111 and an edge sensor 112.

The temperature sensor 110 is installed at the short side of the mold 10 to measure the temperature of the short side surface of the slab 20 to be continuously cast. A plurality of temperature sensors 110 may be disposed in the longitudinal direction of the short side of the mold 10 so as to be spaced apart from each other. In this case, the plurality of temperature sensors 110 may be disposed at equal intervals.

A plurality of the center sensor 111 and the edge sensor 112 may be disposed at equal intervals in the longitudinal direction.

The center sensor 111 is a temperature sensor 110 for measuring the surface temperature at the center of the short side of the slab 20. The center sensor 111 may be installed at a position which is within 50 mm from the center of the short side of the mold 10 or the center thereof.

The edge sensor 112 is a temperature sensor 110 for measuring the surface temperature of the short side edge of the slab 20. The edge sensor 112 may be installed on both sides of the center sensor 111. Further, the edge sensor 112 may be installed at a position within 50 mm from the edge of the mold 10. The temperature of the edge of the slab 20 can not be accurately measured when the edge sensor 112 is installed beyond 50 mm at the edge of the mold 10. [

1, the center sensor 111 is disposed at the center of the short side of the mold 10, and the edge sensor 112 is installed on both sides (the edge 1 and the edge 2) of the center sensor 111 . Further, each of the sensors may be arranged at a plurality of equally spaced rows so as to form columns (one row, two columns, ..., N columns) in the width direction.

One edge sensor 112 is positioned at a distance of 50 mm from the left edge of the mold 10 and the other edge sensor 112 is positioned at a position spaced apart from the left edge of the mold 10 by the edge sensor 112. In the case where the edge sensor 112 is installed on both sides of the center sensor 111, May be located at a position 50 mm away from the right edge of the mold 10.

The setting unit 120 may set the reference temperature by calculating an average of surface temperatures of the short sides of the slab 20 measured for a predetermined time. The predetermined time may be set by the user and may be a time until immediately before the current time point.

Assuming that the surface temperature is measured in units of one second, if the current point in time is n seconds, the reference temperature may be an average of the measured temperatures up to n-1 seconds.

For example, if the current time is 500 seconds (six minutes) after the start of continuous casting, the reference temperature is the average of the temperatures measured up to 499 seconds. Therefore, the reference temperature can be changed in real time.

The average can be calculated by dividing the total sample by the number of samples. In addition, the average can be calculated only for the remaining samples excluding the upper 25% and the lower 25% based on the magnitude of the temperature.

The setting unit 120 can set the center reference temperature and the edge reference temperature respectively when the temperature sensor 110 includes the center sensor 111 and the edge sensor 112. [ The center reference temperature is set based on the surface temperature measured using the center sensor 111, and the edge reference temperature is set based on the surface temperature measured using the edge sensor 112. If the edge sensors 112 are installed on both sides of the center sensor 111, they can be set individually for each sensor.

Time (seconds) One 2 3 4 5 6 7 8 9
Now standard
Temperature Center (℃) 100 101 104 103 102 101 99 98 80 101 edge
(° C) 90 91 94 93 92 91 89 88 72 91

Referring to Table 1, when the current time is 9 seconds, the average of the temperatures measured up to 8 seconds can be calculated by excluding 99 and 98 which are the lower 25%, excluding the upper 25% and 104 and 103, respectively. Therefore, the reference temperature can be 101.

The calculating unit 130 calculates the temperature deviation. The temperature deviation is a temperature difference between the short side surface temperature of the slab 20 measured by the temperature sensor 110 and a reference temperature set in the setting unit 120 after a predetermined time. That is, according to Table 1, the temperature deviation becomes 21 due to the difference between the reference temperature 101 and the present temperature 80. [

The calculation unit 130 can calculate the center temperature deviation and the edge temperature deviation when the temperature sensor 110 includes the center sensor 111 and the edge sensor 112. [ The center temperature deviation is a difference between the center reference temperature and the surface temperature at the present time measured by the center sensor 111. [ The edge temperature deviation is a difference between the edge reference temperature and the surface temperature at the current time measured by the edge sensor 112. [

Referring to Table 1, since the center temperature reference is 101, the center temperature deviation is 21, and the edge temperature reference is 91, so that the temperature deviation becomes 19.

The determination unit 140 compares the temperature deviation and the set value to determine whether a crack in the width direction of the short side of the slab 20 occurs. The set value is a value set by the user and means the possibility of cracking. For example, the setting value may be 20.

The judging unit 140 can compare the temperature deviation with the set value and judge that a crack in the width direction of the short side of the slab 20 occurs when the temperature deviation is equal to or larger than the set value.

When the temperature sensor 110 includes the center sensor 111 and the edge sensor 112, the determination unit 140 may compare the center temperature deviation and the edge temperature deviation with the set values.

Referring to Table 1, the determination unit 140 compares the center temperature deviation 21 and the edge temperature deviation 19 with the set values. When the set value is 20, the center temperature deviation exceeds the set value, and the edge temperature deviation does not exceed the set value.

The judging unit 140 can judge that a crack in the width direction of the short side of the slab 20 occurs when both the center temperature deviation and the edge temperature deviation are equal to or larger than the set value. In other words, referring to Table 1, the judging unit 140 can judge that the widthwise crack of the short side of the slab 20 has not occurred. If the center temperature deviation is 21 and the edge temperature deviation is 22, it is judged that a crack has occurred.

If it is determined that a crack has occurred in the determination unit 140, the determination unit 140 transmits a signal to the scaping driver 150 to enable the scaping driver 150 to operate. Scalling is a step of scraping off the slab 20, and is a method of removing cracks.

3 is a view showing an analysis of a crack index of a crack diagnosis apparatus of a slab 20 according to an embodiment of the present invention.

3 shows the center reference temperature and the edge reference temperature which are set based on the surface temperature measured by the center sensor 111 and the one edge sensor 112. In FIG. Also, the current time is 9 seconds, and the reference temperature is the temperature average measured up to 8 seconds.

According to the graph, the center temperature deviation is 21.5, the edge temperature deviation is 20, and both temperature deviations are equal to or greater than the set value 20. Therefore, it is judged that the slab 20 is cracked.

There is a high possibility that the shape of the slab 20 is changed at a point where the surface temperature of the slab 20 abruptly drops, so that the possibility of cracking at a point where the slab 20 suddenly drops can be increased.

Based on this content, it is possible to judge the possibility of occurrence of a crack in the width direction at a point where the surface temperature of the slab 20 suddenly drops, particularly at a point where the center portion and the edge portion are sharply lowered.

As described above, according to the slab crack diagnosis apparatus 100 according to an embodiment of the present invention, it is possible to easily predict the occurrence of cracks in the width direction of the slab 20.

The slab crack diagnosis apparatus 100 according to an embodiment of the present invention has been described above. Next, a crack diagnosis method of the slab 20 according to an embodiment of the present invention will be described.

4 is a flowchart illustrating a method of diagnosing a crack of a slab 20 according to an embodiment of the present invention.

4, a crack diagnosis method for a slab 20 according to an embodiment of the present invention includes a step S110 of measuring a temperature by a temperature sensor 110, a step S120 of setting a reference temperature S120, (S140) of comparing the temperature deviation with the set value to determine whether a widthwise crack has occurred, and driving the scarping driving unit 150 (S150).

The step S110 of measuring the temperature of the temperature sensor 110 is a step of measuring the surface temperature of the slab 20 to which the temperature sensor 110 provided at the short side of the mold 10 is continuously cast. The temperature sensor 110 can measure the surface temperature for a predetermined time. The temperature sensor 110 may include a center sensor 111 and an edge sensor 112.

The step of setting the reference temperature (S120) is a step in which the setting unit 120 sets the reference temperature. The reference temperature may be an average of the surface temperature for the predetermined time measured previously. However, the average can be calculated only for the remaining samples excluding the upper 25% and the lower 25% based on the temperature magnitude.

When the temperature sensor 110 includes the center sensor 111 and the edge sensor 112, the center reference temperature and the edge reference temperature can be set, respectively.

The step of calculating the temperature deviation (S140) is a step of calculating the temperature deviation between the surface temperature and the reference temperature. In this case, the temperature deviation becomes a deviation of the temperature between the short side surface temperature of the slab 20 measured by the temperature sensor 110 and the reference temperature after a predetermined time.

When the temperature sensor 110 includes the center sensor 111 and the edge sensor 112, it is possible to calculate the center temperature deviation and the edge temperature deviation, respectively.

In step S150, the determination unit 140 compares the temperature deviation and the set value to determine whether or not a crack occurs in the width direction.

The determination unit 140 may include a step of comparing the temperature deviation and the set value and determining that a widthwise crack of the short side of the slab 20 occurs when the temperature deviation is equal to or larger than the set value. The set value can be set by the user, for example, 20.

When the temperature sensor 110 includes the center sensor 111 and the edge sensor 112, the center temperature deviation and the edge temperature deviation are compared with the setting unit 120, ), It can be determined that a crack in the width direction of the short side portion of the slab 20 has occurred.

The step of driving the scarping drive unit 150 (S160) is a step of transmitting a drive signal to the scarping drive unit 150 and performing scaping on the slab 20 when it is determined that a widthwise crack has occurred.

As described above, according to the slab crack diagnosis method according to an embodiment of the present invention, it is possible to easily determine whether or not a crack has occurred, thereby reducing unnecessary scarping operations and reducing steelmaking costs.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

10: Mold
20: Slab
100: Slab crack diagnosis device
110: Temperature sensor
111: Center sensor
112: Edge sensor
120: Setting section
130:
140:
150: Scanning drive

Claims (8)

A plurality of temperature sensors provided at the short sides of the mold for measuring the temperature of the short side surface of the slab to be continuously cast;
A setting unit for setting a reference temperature by calculating the surface temperature average measured for a predetermined time;
A calculating unit for calculating a temperature deviation between the reference temperature and the short side surface temperature of the slab measured by the temperature sensor after the predetermined time; And
And a determination unit for comparing the temperature deviation with a preset value to determine whether a widthwise crack of the slab short side has occurred,
Wherein the temperature sensor comprises:
A center sensor for measuring a surface temperature at the center of the short side of the slab; And
And an edge sensor for measuring a surface temperature of a short side edge of the slab,
Wherein the setting unit sets the center reference temperature using the center sensor and the edge reference temperature using the edge sensor,
Wherein the calculating unit calculates a center temperature deviation based on the center reference temperature and an edge temperature deviation based on the edge reference temperature,
Wherein the judging section judges that a crack in the width direction of the short side of the slab is generated when both the center temperature deviation and the edge temperature deviation are equal to or more than the set value.
delete delete The method according to claim 1,
Wherein the edge sensor is installed at a position spaced apart from the edge of the mold by 50 mm or less.
Measuring a surface temperature of a slab continuously cast by a temperature sensor provided at a short side of the mold for a preset time;
Calculating an average of the surface temperatures measured during the predetermined time to set a reference temperature;
Calculating a temperature difference between the reference temperature and the short side surface temperature of the slab measured by the temperature sensor after the predetermined time; And
And comparing the temperature deviation with a preset value to determine whether a widthwise crack of the slab short side portion has occurred,
Wherein the temperature sensor comprises:
A center sensor for measuring a surface temperature at the center of the short side of the slab; And
And an edge sensor for measuring a surface temperature of a short side edge of the slab,
Wherein the step of setting the reference temperature comprises:
Setting a center reference temperature according to the surface temperature measured by the center sensor and an edge reference temperature according to the surface temperature measured by the edge sensor, respectively.
delete 6. The method of claim 5,
Wherein the step of calculating the temperature deviation comprises:
And calculating a center temperature deviation according to the center reference temperature and an edge temperature deviation according to the edge reference temperature, respectively.
8. The method of claim 7,
The step of determining whether or not the crack occurs may include:
And judging that a crack in the width direction of the short side of the slab is generated when both the center temperature deviation and the edge temperature deviation are equal to or more than the set value.

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