KR20120032924A - Method for estimating steel component during mixed grade continuous casting - Google Patents

Method for estimating steel component during mixed grade continuous casting Download PDF

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KR20120032924A
KR20120032924A KR1020100094491A KR20100094491A KR20120032924A KR 20120032924 A KR20120032924 A KR 20120032924A KR 1020100094491 A KR1020100094491 A KR 1020100094491A KR 20100094491 A KR20100094491 A KR 20100094491A KR 20120032924 A KR20120032924 A KR 20120032924A
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tundish
mold
molten steel
discharge amount
steel
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KR1020100094491A
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Korean (ko)
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KR101224982B1 (en
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김경수
문홍길
안재환
최주태
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현대제철 주식회사
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/124—Accessories for subsequent treating or working cast stock in situ for cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/12—Accessories for subsequent treating or working cast stock in situ
    • B22D11/126—Accessories for subsequent treating or working cast stock in situ for cutting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/16—Controlling or regulating processes or operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D41/00—Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like

Abstract

PURPOSE: A steel type prediction method for continuous casting of mixed steel type is provided to reduce the costs for processing mixed steel scrap by variably controlling the position for cutting strand. CONSTITUTION: A steel type prediction method for continuous casting of mixed steel type is as follows. The molten metal level(L) of a tundish and the discharge amount(T) of a mold are set(S10). The discharge amounts(A1,A2,p) of molds according to changes in the molten metal level of the tundish are calculated from the set L and T(S20). The molten metal level(X0) according to changes in the discharge amount of the mold is calculated from the set L and T(S30). The component concentration of molten metal according to the molten metal level of the tundish and the discharge amount of the mold is calculated from the calculated discharge amounts of molds and the molten metal level of the tundish(S40). The obtained component concentration is compared with the set minimum and maximum available values in order to predict steel type or mixed band(S50).

Description

METHOD FOR ESTIMATING STEEL COMPONENT DURING MIXED GRADE CONTINUOUS CASTING}

The present invention relates to a method for predicting steel grade during continuous casting of two steel grades, which predicts the degree of mixing of steel species mixed and discharged in a tundish for a predetermined time when continuously casting different steels (called different steel grades).

Continuous casting machine is a facility that produces cast steel of a certain size by receiving molten steel produced in a steelmaking furnace and transported to ladle in a tundish and then feeding it into a mold for continuous casting machine.

The continuous casting machine includes a ladle for storing molten steel, a continuous casting machine mold for cooling the tundish and the molten steel discharged from the tundish into a strand having a predetermined shape, and a strand formed from the mold connected to the mold. It includes a plurality of pinch rolls to move.

In other words, the molten steel tapping out of the ladle and the tundish is formed of a strand having a predetermined width, thickness, and shape in a mold and is transferred through a pinch roll, and the strand transferred through the pinch roll is cut by a cutter to have a predetermined shape. It is made of a slab (Slab) or a slab (Bloom), billet (Billet) and the like.

In the case of the ladle is composed of a plurality of ladle, if the molten steel of the first ladle is all supplied to the tundish, the molten steel is supplied again to the tundish in the second ladle successively.

In general, in order to continuously and efficiently produce a variety of steel grades, only ladles are exchanged and continuous steel casting operations are performed. Since the first steel grade before ladle exchange and the second steel after ladle exchange are mixed with each other in the tundish to produce mixed steel grades (outside the component separation), it is necessary to predict and remove the mixed steel grade in advance according to continuous casting. .

An object of the present invention is to predict the degree of mixing of the steel species mixed and discharged in the tundish for a certain time during continuous casting of the steel sheet to predict the grade of the steel grade during continuous casting of different steel grades to minimize the mixed band To provide.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not intended to limit the invention to the particular embodiments that are described. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, There will be.

The steel grade prediction method of the present invention for achieving the above object comprises a first step of setting the molten steel level (L) of the tundish as the operation variable and the discharge amount (T) of the mold, respectively; A second step of calculating discharge amounts (A 1 , A 2 , p) of various molds according to variations in the tundish molten steel level using the L value and the T value; A third step of calculating the molten steel level (X 0 ) of the tundish according to the variation of the mold discharge amount using the L value and the T value; Steel grade component concentration according to the molten steel level (L) of the tundish and the discharge amount (T) of the mold by using the calculated discharge amounts (A 1 , A 2 , p) of the various molds and the molten steel level (X 0 ) of the tundish. Calculating and obtaining a fourth step; And a fifth step of predicting the steel grade or the mixed band by comparing the obtained steel grade component concentration with a set minimum and maximum allowable value, respectively.

Specifically, the fourth step may include: calculating a time t calculated from the time point at which the new molten steel is added to the tundish by dividing by the molten steel level (X 0 ) of the tundish according to the change in the discharge amount; A 42nd step of adding the set constant after exponentially multiplying the value calculated in the 41th step by the discharge amount p of the mold according to the variation of the molten steel level of the tundish; A 43rd step of calculating by dividing the value A 1 and A 2 by the value derived in step 42; And a step 44 to obtain a type of steel component concentration by adding the discharge amount (A 2) of the mold in accordance with the fluctuation of the molten steel level in the dish turns with the value calculated in the step 43; characterized in that it comprises a.

In addition, the A 1 is a function of the discharge amount (T) of the turn is larger mold sensitivity than the fluctuation of the molten steel level (L) of the dish, wherein A 2 is the sensitivity more than the variation of the turn-molten steel level (L) of the dish Is a function of the ejection amount T of the large mold, p is a function of the ejection amount T of the mold whose sensitivity is greater than the variation of the molten steel level L of the tundish, and X 0 is the ejection amount T of the mold It is characterized in that it is a function of the molten steel level (L) of the tundish having a greater sensitivity than the fluctuation of.

The fifth step is the first steel grade when the obtained steel grade component concentration is less than or equal to the minimum allowable value. In this case, it is characterized by determining by predicting the second steel type.

As described above, according to the present invention, through the prediction process of the steel species during continuous casting of two steel grades , it is possible to estimate the time when the component component of the strand occurs according to the operating variables ( L, T ) and the operating time ( t ) strands By variably adjusting the cutting position, it is possible to reduce the scrap processing ratio of the mixed slab, and to minimize the occurrence of the component gap, thereby improving the error rate.

1 is a side view showing a continuous casting machine according to an embodiment of the present invention.
FIG. 2 is a conceptual view illustrating the continuous casting machine of FIG. 1 based on the flow of molten steel M. Referring to FIG.
3 is a plan view of the tundish of FIG. 2 seen from above;
4 and 5 are flowcharts showing the steel sheet prediction process during continuous casting of two steel types according to an embodiment of the present invention.
FIG. 6 is a view for explaining a steel type mixing state with time when a new steel type is added to a tundish. FIG.
FIG. 7 is a diagram illustrating steel grades and component gaps according to steel grade component concentrations.
8 is a graph showing a numerical analysis and prediction model according to the present invention.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention. Like elements in the figures are denoted by the same reference numerals wherever possible. In addition, detailed descriptions of well-known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

1 is a side view showing a continuous casting machine according to an embodiment of the present invention.

Referring to this drawing, the continuous casting machine may include a tundish 20, a mold 30, secondary cooling tables 60 and 65, a pinch roll 70, and a cutter 90.

A tundish 20 is a container for receiving molten metal from a ladle 10 and supplying molten metal to a mold 30. Ladle 10 is provided with a pair of first ladle 11 and the second ladle 12, and alternately receives the molten steel to be supplied to the tundish 20 alternately. In the tundish 20, the supply rate of the molten metal flowing into the mold 30 is controlled, the molten metal is distributed to each mold 30, the molten metal is stored, and the slag and the nonmetallic inclusions are separated.

The mold 30 is typically made of water-cooled copper and allows the molten steel to be primary cooled. The mold 30 has a pair of structurally opposed faces open to form a hollow portion for receiving molten steel. In the case of manufacturing a slab, the mold 30 includes a pair of barriers and a pair of end walls connecting the barriers. Here, the short wall has a smaller area than the barrier. The walls of the mold 30, mainly short walls, may be rotated away from or close to each other to have a certain level of taper. This taper is set to compensate for shrinkage caused by solidification of the molten steel M in the mold 30. The degree of solidification of the molten steel (M) will vary depending on the carbon content, the type of powder (steel cold Vs slow cooling), casting speed and the like depending on the steel type.

The mold 30 maintains the shape of the strands extracted from the mold 30 and forms a strong solidification angle or solidified shell 81 so that molten metal, which is still less solidified, does not flow out. Play a role. The water cooling structure includes a method of using a copper pipe, a method of drilling a water cooling groove in the copper block, and a method of assembling a copper pipe having a water cooling groove.

The mold 30 is oscillated by the oscillator 40 to prevent the molten steel from sticking to the wall of the mold. Lubricants are used to reduce friction between the mold 30 and the strands during oscillation and to prevent burning. Lubricants include splattered flat oil and powder added to the molten metal surface in the mold 30. The powder is added to the molten metal in the mold 30 to become slag, as well as the lubrication of the mold 30 and the strands, as well as the oxidation and nitriding prevention and thermal insulation of the molten metal in the mold 30, and the non-metal inclusions on the surface of the molten metal. It also performs the function of absorption. In order to inject the powder into the mold 30, a powder feeder 50 is installed. The part for discharging the powder of the powder feeder 50 faces the inlet of the mold 30.

The secondary cooling zones 60 and 65 further cool the molten steel primarily cooled in the mold 30. The primary cooled molten steel is directly cooled by the spray means 65 for spraying water while maintaining the solidification angle by the support roll 60 not to be deformed. Strand coagulation is mostly achieved by the secondary cooling.

The drawing device adopts a multidrive method using a plurality of sets of pinch rolls 70 and the like to pull out the strands without slipping. The pinch roll 70 pulls the solidified tip of the molten steel in the casting direction, thereby allowing the molten steel passing through the mold 30 to continuously move in the casting direction.

The cutter 90 is formed to cut continuously produced strands to a constant size. As the cutter 90, a gas torch, a hydraulic shear, or the like can be employed.

FIG. 2 is a conceptual view illustrating the continuous casting machine of FIG. 1 based on the flow of molten steel M. Referring to FIG.

Referring to this figure, the molten steel (M) is to flow to the tundish 20 in the state accommodated in the ladle (10). For this flow, the ladle 10 is provided with a shroud nozzle 15 extending toward the tundish 20. The shroud nozzle 15 extends to be immersed in the molten steel in the tundish 20 so that the molten steel M is not exposed to air and oxidized and nitrified. The case in which the molten steel M is exposed to air due to breakage of the shroud nozzle 15 is referred to as open casting.

The molten steel M in the tundish 20 flows into the mold 30 by a submerged entry nozzle 25 extending into the mold 30. The immersion nozzle 25 is disposed in the center of the mold 30 so that the flow of molten steel M discharged from both discharge ports of the immersion nozzle 25 can be symmetrical. The start, discharge speed, and stop of the discharge of the molten steel M through the immersion nozzle 25 are determined by a stopper 21 installed in the tundish 20 corresponding to the immersion nozzle 25. Specifically, the stopper 21 may be vertically moved along the same line as the immersion nozzle 25 to open and close the inlet of the immersion nozzle 25. Control of the flow of the molten steel M through the immersion nozzle 25 may use a slide gate method, which is different from the stopper method. The slide gate controls the discharge flow rate of the molten steel M through the immersion nozzle 25 while the sheet material slides in the horizontal direction in the tundish 20.

The molten steel M in the mold 30 starts to solidify from the part in contact with the wall surface forming the mold 30. This is because heat is more likely to be lost by the mold 30 in which the periphery is cooled rather than the center of the molten steel M. The rear portion along the casting direction of the strand 80 is formed by the non-solidified molten steel 82 being wrapped around the solidified shell 81 in which the molten steel M is solidified by the method in which the peripheral portion first solidifies.

As the pinch roll 70 (FIG. 1) pulls the tip portion 83 of the fully solidified strand 80, the unsolidified molten steel 82 moves together with the solidified shell 81 in the casting direction. The uncondensed molten steel 82 is cooled by the spray means 65 for spraying the cooling water in the above movement process. This causes the thickness of the uncooled steel (82) in the strand (80) to gradually decrease. When the strand 80 reaches a point 85, the strand 80 is filled with the solidification shell 81 in its entire thickness. The solidified strand 80 is cut to a certain size at the cutting point 91 and divided into slabs P such as slabs.

3 is a plan view from above of the tundish of FIG.

Referring to this figure, the tundish 20 has a body 22 that is open at the top to receive the molten steel (M) that is stepped out of the ladle (10). The body 22 may include an iron shell disposed outside and a refractory layer disposed inside the iron shell.

The shape of the body 22 may be a variety of forms, for example, straight, etc., in this embodiment illustrates the body 22 of the 'T' shape.

A portion 23 of the body 22 is formed with a pouring portion 23. The pouring portion 23 is a portion where the molten steel M flowing through the shroud nozzle 15 of the ladle 10 falls. The pouring portion 23 may communicate with the tapping portion 24 having a larger area.

The tapping part 24 is a part for guiding the molten steel M received through the pouring part 23 to the mold 30. A plurality of tapping holes 24a may be opened in the tapping part 24. An immersion nozzle 25 is connected to each tap 24a, and the immersion nozzle 25 guides the molten steel M of the tundish 20 to flow into the mold 30.

The tundish 20 configured as described above has a molten steel discharged from the ladle 10 installed on the upper portion thereof, the flow of which is changed by the inner partition, and partly vortexed, and part of the tundish 20 is discharged through the immersion nozzle 25. Will circulate inside the tundish 20.

At present, in order to continuously and efficiently produce various steel grades (two kinds of steel), only the ladles 11 and 12 are exchanged, and two kinds of continuous casting operations are performed. Since the first steel grade before ladle exchange and the second steel species after ladle exchange are mixed with each other in the tundish to produce mixed steel grades (outside the component gap), the mixed steel grades need to be predicted and removed in advance according to continuous casting. .

The mixing pattern of this type of steel is changed according to the operation method.

4 and 5 are flowcharts showing a steel sheet prediction process during continuous casting of two steel types according to an embodiment of the present invention, with reference to the accompanying drawings to explain the steel sheet prediction process.

First, when the injection of the first steel type of the first ladle 11 when the second steel casting in the continuous casting process as shown in FIG. 6 is completed, a new steel, for example, already inside the tundish 20 through the second ladle 12 A second type of steel other than the first type of steel being introduced and discharged into the tundish 20 is introduced into the tundish 20. At this time, the new second steel grade is mixed with the previous first steel grade while flowing along the flow in the tundish.

That is, the new second steel grade introduced from the second ladle 12 is lowered to the lower portion of the tundish 20 while being mixed with the previous first steel grade, and a part of the mixed steel grade is the portion of the tundish 20. Is discharged to the mold 30 through the immersion nozzle 25, and part of it continues to be mixed with the previous first steel species to recycle the inside of the tundish 20, after a certain time the tundish inside is gradually new It is completely changed to steel grade.

Here, the concentration value of the new second steel grade may be defined as "1", and the concentration value of the previous first steel grade may be defined as "0", and the mixing degree may be represented as 0 to 1 value.

That is, some molten steel is discharged while the new molten steel of the second steel is mixed with the molten steel of the first steel, and the rest is continuously mixed with the previous steel while continuously recycling the tundish. The lowest value of the steel grade mixed concentration value is present at some point inside the tundish rather than the immersion nozzle 25 of the tundish 20, and the immersion nozzle 25 has a value between the maximum value and the minimum value of the steel type mixed value. do.

By the way, the maximum value of the steel grade mixed value in the tundish 20 is determined to be "1", but the minimum value is not known because it changes with time.

The present invention focuses on this, the mixed concentration value of the steel species discharged to the immersion nozzle 25 of the tundish 20, the molten steel level of the tundish 20, the operation variable and the discharge amount of the mold 30 and the new second steel grade The concentration value of the mixture is determined according to the input time so that the first steel grade, the mixed band, or the second steel grade of the strand discharged from the mold can be predicted.

As described above, a method of predicting whether the steel grade or the component separation is discharged through the immersion nozzle 25 of the tundish 20 during continuous casting of the two steel types will be described with reference to FIGS. 4 and 5.

First, in the processing system (not shown), the molten steel level L of the tundish 20, which is an operation variable, and the discharge amount T of the mold 30 are respectively set by the user (S10). Since the molten steel level L of the tundish 20 and the discharge amount T of the mold 30 vary depending on the operating conditions such as the casting speed and the shape of the tundish 20, a value under a specific operating condition is set. .

Although not shown, the processing system includes input means for inputting parameters such as various variables and coefficients, a control unit for calculating a component concentration of steel grades according to arithmetic algorithms and various variables and coefficients stored in a memory, and a calculated component concentration. It may be configured as a computer including a display unit for displaying in text or graph by the control unit.

Subsequently, the processing system uses the molten steel level L of the tundish 20 and the discharge amount T of the mold 30 set above, and thus the discharge amount A of the various molds 30 according to the variation of the tundish molten steel level. 1 , A 2 , p ) is calculated (S20).

Then, using the molten steel level L of the tundish 20 and the discharge amount T of the mold 30, the molten steel level X 0 of the tundish 20 according to the variation of the mold discharge amount is calculated (S30). ).

The discharge amounts A 1 , A 2 , p of the various molds 30 and the molten steel level X 0 of the tundish 20 are obtained by Equation 1 below.

Equation 1

Figure pat00001

Where L is the molten steel level [%] of the tundish 20 and T is the discharge amount [ton / min] of the mold 30.

In the A 1 is a function of the discharge amount (T) of the tundish 20 of molten steel level (L) is larger mold 30 sensitivity than the variation in, A 1 is the molten steel level in the tundish 20, (L It has a sensitivity of about 23 times with respect to the discharge amount T of the mold 30 than the variation of).

Wherein A 2 is turned the sensitivity than the variation of the dish 20, molten steel level (L) as a function of the more the discharge amount (T) of a larger mold (30), A 2 is a molten steel level (L) of the tundish (20) It is about 2.2 times more sensitive to the discharge amount T of the mold 30 than the variation of.

Wherein p is a function of the discharge amount (T) of the tundish 20 of molten steel level (L) is larger mold 30 sensitivity than the variation in, p is a variation of the tundish 20, the molten steel level (L) of In addition, the sensitivity has a sensitivity of about 2.2 times with respect to the discharge amount T of the mold 30.

Wherein X 0 is a function of the molten steel level (L) of the mold 30, the discharge amount (T), the sensitivity than the variation larger tundish 20 of the, X 0 is a variation in discharge amount (T) of the mold (30) The sensitivity is approximately 4.7 times the molten steel level L of the tundish 20.

Sensitivity at A 1 , A 2 , p and X 0 is obtained as the ratio of each coefficient of the molten steel level L of the tundish 20 and the discharge amount T of the mold 30.

As described above, when the discharge amounts A 1 , A 2 , p of the various molds 30 and the molten steel level X 0 of the tundish 20 are obtained, the processing system uses A 1 , A 2 , p and X 0 . The steel grade component concentration C according to the molten steel level L of the tundish 20 and the discharge amount T of the mold 30 is calculated and stored by using a stored algorithm (S40).

The process (S40) of obtaining the steel grade component concentration ( C ) above is shown in detail in FIG. 5.

That is, the processing system calculates by dividing the time t counted from the time when the new molten steel is put into the tundish by the molten steel level ( X 0 ) of the tundish 20 according to the change in the discharge amount (S41).

The value calculated in step S41 is exponentially multiplied by the discharge amount p of the mold 30 according to the fluctuation of the molten steel level of the tundish 20, and then the set constant is added (S42). Here, the set constant may be "1".

Subsequently, the mold discharge amounts A 1 and A 2 are subtracted and calculated by dividing the subtracted value by the value derived in S42 (S43).

The value calculated in S43 is added to the discharge amount A 2 of the mold 30 according to the variation of the tundish molten steel level L to obtain a steel type component concentration (S44).

As shown in FIG. 5, the algorithm for obtaining the steel grade component concentration C may be represented by Equation 2 below. Various parameters A 1 , A 2 , p, and X 0 of Equation 2 are obtained by Equation 1.

Equation 2

Figure pat00002

Here, t is the elapsed time from the time when a new molten steel was put into a tundish.

Subsequently, the processing system compares the steel grade component concentration C obtained in step S40 with the minimum and maximum allowable values set as shown in FIG. 7, respectively, and predicts the steel grade or mixed band. That is, the molten steel level L of the tundish 20, the discharge amount A 2 of the mold 30, and the new molten steel are discharged from the tundish 20 according to the elapsed time from the time when the new molten steel is introduced into the tundish 20. It is possible to predict whether the strands 80 are out of steel grade or component spacing.

Here, when the obtained steel grade component concentration is less than or equal to the minimum allowable value, it is the first steel grade, and when the steel grade component concentration is located between the minimum and maximum allowable values, the component grade is outside, and the steel grade component concentration is greater than or equal to the maximum allowable value. Prediction can be made based on the second steel grade.

In this way, through the process of predicting steel grades during continuous casting of two kinds of steel , it is possible to estimate the timing of occurrence of the constituent outside of the strand according to the operating variables ( L, T ) and the operating time ( t ), and to adjust the position at which the strand is cut. As a result, the scrap processing ratio of the mixed slab (component gap) can be reduced, and the occurrence rate of the component gap can be minimized to improve the error rate.

As a result of experiments using the water model to predict the steel composition concentration, the results as shown in FIG. 8 were obtained. In conclusion, the predictive model accuracy (R 2 ) was 96.3%.

The experiments were variously performed according to the time change (group of solid lines) and the discharge amount of the mold 30 (each solid line in the solid line group) in which a new molten steel was introduced into the tundish 20. In the graph, the dot is the value obtained by numerical analysis according to the present invention, and the solid line is the predictive model through the numerical model.

In this way, the steel mixture mixture prediction method for continuous casting of two steel grades can be quickly and accurately predicted even when various operating conditions change, so it can be directly put into the actual operation site, and it is possible to predict the outside of the component grade of the two steel grades. Clearly distribute between products.

The present invention has been described with reference to the preferred embodiments, and those skilled in the art to which the present invention pertains to the detailed description of the present invention and other forms of embodiments within the essential technical scope of the present invention. Could be. Here, the essential technical scope of the present invention is shown in the claims, and all differences within the equivalent range will be construed as being included in the present invention.

10: Ladle 11: First Ladle
12: second ladle 15: shroud nozzle
20: Tundish 25: Immersion Nozzle
30: mold 40: mold oscillator
50: powder feeder 51: powder layer
52: liquid fluidized bed 53: lubricating layer
60: support roll 65: spray
70: pinch roll 80: strand
81: solidified shell 82: unsolidified molten steel
83: tip 85: solidification completion point

Claims (13)

A first step of setting the molten steel level (L) of the tundish and the discharge amount (T) of the mold as operating variables, respectively;
A second step of calculating discharge amounts (A 1 , A 2 , p) of various molds according to variations in the tundish molten steel level using the L value and the T value;
A third step of calculating the molten steel level (X 0 ) of the tundish according to the variation of the mold discharge amount using the L value and the T value;
Steel grade component concentration according to the molten steel level (L) of the tundish and the discharge amount (T) of the mold by using the calculated discharge amounts (A 1 , A 2 , p) of the various molds and the molten steel level (X 0 ) of the tundish. Calculating and obtaining a fourth step; And
And a fifth step of predicting steel grade or mixed band by comparing the obtained steel grade component concentration with a set minimum and maximum allowable value, respectively.
The method according to claim 1,
In the fourth step,
A 41 th step of calculating the time t counted from the time when the new molten steel is added to the tundish by dividing the tumbled steel level (X 0 ) according to the discharge amount;
A 42nd step of adding the set constant after exponentially multiplying the value calculated in the 41th step by the discharge amount p of the mold according to the variation of the molten steel level of the tundish;
A 43rd step of calculating by dividing the value A 1 and A 2 by the value derived in step 42; And
And a 44th step of obtaining a steel grade component concentration by adding the discharge amount (A 2 ) of the mold according to the variation of the molten steel level of the tundish to the value calculated in the 43rd step.
The method according to claim 2,
The constant set in step 42 is a method for predicting steel grades when performing yeongangjong.
The method according to claim 2,
A 1 is a method for predicting steel grades for two-stranded casting , which is a function of a discharge amount T of a mold having a sensitivity higher than a variation of the molten steel level (L) of the tundish.
The method of claim 4,
Wherein A 1 has a sensitivity of about 23 times with respect to the discharge amount (T) of the mold than the variation of the molten steel level (L) of the tundish.
The method according to claim 2,
A 2 is a method for predicting steel grades in two-stranded strand casting as a function of a discharge amount T of a mold having a sensitivity higher than a variation of the molten steel level (L) of the tundish.
The method of claim 6,
Wherein A 2 has a sensitivity of about 2.2 times the discharge amount (T) of the mold than the fluctuation of the molten steel level (L) of the tundish, the steel grade prediction method.
The method according to claim 2,
Wherein p is a function of dwell yigangjong give grades prediction method for a discharge amount (T) of the sensitivity variation is larger than the mold of the molten steel level (L) of the tundish.
The method according to claim 8,
P is a sensitivity of about 2.2 times with respect to the discharge amount (T) of the mold than the variation of the molten steel level (L) of the tundish.
The method according to claim 2,
X 0 is a method for predicting steel grades in two-stranded casting as a function of the molten steel level (L) of the tundish, which is more sensitive than the variation in the discharge amount (T) of the mold.
The method according to claim 10,
Wherein X 0 has a sensitivity of about 4.7 times with respect to the molten steel level (L) of the tundish than the variation of the discharge amount (T) of the mold steel grade prediction method.
The method according to claim 1,
Wherein A 1 , A 2 , X 0 and p are respectively predicted by the following equation, the class of two steel grades performance.
Equation
Figure pat00003

Where L is the molten steel level [%] of the tundish and T is the discharge amount [ton / min] of the mold.
The method according to claim 1,
The fifth step,
If the obtained steel grade component concentration is less than the minimum allowable value, it is the first grade, and if the steel grade component concentration is located between the minimum and maximum allowable values, it is out of component grade; Method for predicting steel grades when performing two kinds of performances.
KR1020100094491A 2010-09-29 2010-09-29 Method for estimating steel component during mixed grade continuous casting KR101224982B1 (en)

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WO2015099213A1 (en) * 2013-12-23 2015-07-02 주식회사 포스코 Method for continuously casting different grades of steel
CN104841902A (en) * 2015-05-15 2015-08-19 北京首钢自动化信息技术有限公司 Optimization device and method for casting blank production plan during period of rapidly exchanging tundish
CN113182500A (en) * 2021-06-30 2021-07-30 北京科技大学 Physical model-based method and system for predicting length and component change of mixed casting blank

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JP2000000645A (en) 1998-06-16 2000-01-07 Tokai Kogyo Kk Steel kind judging method in sequentially continuous casting steel of different kind
JP3548443B2 (en) 1998-12-17 2004-07-28 新日本製鐵株式会社 Continuous casting method for continuously casting different types of molten steel
KR100419886B1 (en) * 1999-12-21 2004-03-02 주식회사 포스코 Prediction method of the steel component during mixed grade continuous casting

Cited By (7)

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Publication number Priority date Publication date Assignee Title
WO2015099213A1 (en) * 2013-12-23 2015-07-02 주식회사 포스코 Method for continuously casting different grades of steel
CN105848808A (en) * 2013-12-23 2016-08-10 株式会社Posco Method for continuously casting different grades of steel
EP3088102A4 (en) * 2013-12-23 2016-11-02 Posco Method for continuously casting different grades of steel
EP3088102B1 (en) 2013-12-23 2017-11-08 Posco Method for continuously casting different grades of steel
CN104841902A (en) * 2015-05-15 2015-08-19 北京首钢自动化信息技术有限公司 Optimization device and method for casting blank production plan during period of rapidly exchanging tundish
CN113182500A (en) * 2021-06-30 2021-07-30 北京科技大学 Physical model-based method and system for predicting length and component change of mixed casting blank
CN113182500B (en) * 2021-06-30 2021-10-15 北京科技大学 Physical model-based method and system for predicting length and component change of mixed casting blank

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