Title of Invention: bath surface flow control apparatus and method using the same bath surface flow control

Art

[1]

The present invention relates to a bath surface flow control apparatus, and relates to a bath surface flow control method using the same, more particularly, to bath surface flow control method using the molten steel bath surface which is easy to control the flow of the bath surface flow control apparatus, and this mold.

BACKGROUND

[2]

In general, continuous casting (continuous casting) process continuously by drawing the lower side of the mold the cast steel (slab), Double (bloom) for continuously injecting into the molten steel in a constant-sheet mold, reaction laborious molten steel in the mold, the billet (billet ) is a step for preparing semi-finished products of various shapes, such as. Mold is that the reaction is injected the molten steel by cooling water circulating therein is be made of a certain type. That is, the molten steel in a molten state, and high reaction by the primary cooling function in the template, the unsolidified molten steel, the pull-out from the mold is complete the solid was solidified by the cooling water injected from the secondary cooling zone which extends to the mold lower proceeds side of the main state is formed.

[3]

Primary cooling of the mold is the most important in determining the surface quality of the cast steel (slab). That is, the primary cooling is influenced by the flow of the molten steel in the mold, the molten steel and the mold is generally lubricated and molten steel bath surface (meniscus) mold flux (flux mold) formed on to the insulation of the molten steel between the inner wall coated with. However, when the fast flow or drift (bias flow) of the molten steel bath surface (meniscus) in the mold occurs, the incorporation of the mold flux is caused, resulting in a defect is generated in the cast steel in accordance with.

[4]

Therefore, in order to prevent the cast steel bath surface flow defects according to the need to measure in real time the flow of intra-mold molten steel bath surface during the casting operation. However, the molten steel is difficult to measure since the maintenance of a high temperature state in the mold, the flow pattern (or a flow pattern, the fluid) of the bath surface in real time. Further, it can not be observed because it is a mold flux applied to the surface of molten steel bath surface, the worker by the naked eye, such as a commercial or a camera to be OK.

[5]

On the other hand, as a method for detecting the bath surface flow of a molten steel in a mold, Patent Application No. 10-12244323 rebelgye eddy current using an electromagnetic induction coil as in the call: measuring the height of the bath surface through the (ECLM eddy current level meter), and this a technique for controlling the height of the bath surface is used with. However, it is to measure the whole of the bath-surface molten steel flow is not possible, because the above-described method only measures the height of the one point.

[6]

In addition, the width of the mold there is a variable depending on the desired size of the cast, it is not easy even measure the bath surface in accordance with the variable shape of this mold in real time.

Detailed Description of the Invention

SUMMARY

[7]

The present invention provides a control method using the bath surface visible the flow of intra-mold molten steel bath surface, and by using this bath surface to control the bath surface flow, and this flow control apparatus.

[8]

The invention is easy to monitor for a normal or abnormal state of the bath surface flow, and provides for reducing defects on the bath surface flow casting apparatus and the molten steel flow control method.

[9]

The present invention provides to the flow of the bath surface to adjust the control method, the bath surface, which reduces the cast defects generated in accordance with the bath surface flow flow control apparatus and the bath surface flow control method using the same in accordance with the flow pattern in the form of intra-mold molten steel bath surface.

[10]

The present invention provides a bath-surface visualization apparatus and method using the same bath surface visible to the bath surface visible regardless of shape in the cast steel width.

Problem solving means

[11]

Bath surface flow control apparatus according to the present invention, a plurality of side warmth for measuring the temperature in the width direction of the mold the molten steel accommodated in the interior at a plurality of locations; By detecting the position by the relative temperature values ​​measured by the plurality of side warmth to the bath surface flow patterns of the molten steel, and comparing the temperature values ​​measured by the plurality of side warmth with relatively normal or abnormal flow condition of the molten steel bath surface bath surface flow detection unit for determining a; Is provided on the outside of the template, by generating a magnetic field, the magnetic field generating unit for controlling the flow of the molten steel by the magnetic field; If the detected bath surface flow conditions in the bath surface flow detection unit when it is determined as normal, and to maintain operation of the magnetic field generating unit in the present state, the detected bath surface flow state is determined as abnormal, the operations of the magnetic field generating unit include; to control the flow control unit for adjusting the bath surface so that the normal flow.

[12]

The bath surface flow detection unit is relatively expressed by the temperature measurement values ​​measured by the plurality of side warmth as location-specific temperature value of the molten steel bath surface, and detects a flow pattern of the molten steel bath surface.

[13]

To the bath surface flow detection unit, comparing whether the calculated temperature difference between the respective temperatures of said plurality of side warmth, and said calculated plurality of temperature differences, each with the reference temperature range, the flow state of the molten steel bath surface it is determined as normal or abnormal.

[14]

The bath surface flow detection unit, and for each of the plurality of side warmth calculating the temperature difference between the other remaining side warmth, and compared with the reference temperature range, and determines the bath surface flow state as normal or abnormal.

[15]

The bath surface flow detection unit, when all of the difference values ​​of the respective temperature other remaining side warmth for each of the plurality of side warmth is incorporated into the reference temperature range and determine the bath surface flow to the normal state, the plurality of side warmth the bath surface flow conditions outside the at least one difference value is based on the temperature range of the difference value and each of the other remaining side temperature warmth for each it is determined as abnormal.

[16]

The bath surface flow detection unit, whether or not the calculated temperature difference between the plurality of side warmth of, side warmth in the both ends, and the temperature difference respectively between side warmth located on the calculated both ends contains a reference temperature range comparison, to determine the flow state of the molten steel bath surface in a normal or abnormal.

[17]

The bath surface flow detection unit, the plurality of side warmth of, side temperature and a temperature between side warmth provided on one end of warmth in the heart of the car and the temperature difference between the side of warmth provided to the temperature and the other end on the side of warmth in the center calculated, and based on the temperature difference between the comparison temperature difference between the side of warmth provided to the temperature and the one end of the side warmth in the center of the reference temperature range, and the side of warmth provided to the temperature and the other end on the side of warmth in the center of the compared to the temperature range, and determines a flow state of the molten steel bath surface in a normal or abnormal.

[18]

The bath surface detection unit, the flow state when the difference between the temperature difference and a temperature between side warmth provided on the heat and the other end located in the center between the side warmth and side warmth provided on one end located in the center of both included in the standard temperature bath surface a is determined as normal, when one or more of the temperature difference between the side warmth and side warmth provided to the other end located on the temperature difference and the center between the side warmth and side warmth provided on one end located in the center, at least one is outside the reference temperature range and determines a flow state of the bath surface normal.

[19]

The bath surface flow detection unit, calculates the average temperature on the side of warm temperatures of the plurality, and the plurality of side warmth, the side warm position to the difference and the other end between the temperature and the average temperature on the side of warmth in the one end a and calculates the difference between the temperature and the average temperature, as compared to the temperature difference between the temperature at the side of warmth in the one side and the other side edge and the mean temperature and a reference temperature range, determining a flow state of the molten steel bath surface in a normal or abnormal do.

[20]

The bath surface flow detection unit, determines the normal flow conditions of the bath surface when the average temperature described above in the one end between the side warm temperature difference and the mean temperature and the temperature between side warmth located at the other end of the car all included in the standard temperature range, and it determines a flow state of the bath surface as abnormal when said average temperature and said one side warmth temperature between in the end car and at least one of the temperature difference between the average temperature and the side of warmth in the other end is outside the reference temperature range.

[21]

The bath surface, and the flow detection unit, measured on the cast casting, the temperature of the side of warmth in the side warmth, one side and the other end located in one of a plurality of side warmth installed so listed, along the width direction of the mold, the center in real time, wherein and calculating a time series average temperature on the side of warmth in the heart, wherein the clock calculates the temperature difference between the side warmth in the thermal average temperature and one and the other ends respectively, and the calculated output time series average temperature and one and the other end and in comparison with the side of the reference temperature range, the temperature difference between the warm located, and it determines a flow state of the molten steel bath surface in a normal or abnormal.

[22]

The bath surface flow detection unit, calculated from the casting initially to discharge the molten steel in the mold measure the temperature on the side of warmth in the center in real time the time-series average temperature, and constant side warmth time series average temperature in the center after the calculated up to the point, using a warm side temperature of each is located on the one side and the other end determines the state of the molten steel bath surface flow.

[23]

The bath surface flow detection unit, between the side warmth in the temperature difference and the time-series average temperature and the other end on the side of warmth in the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end temperature difference between both reference temperatures when included in the range of determining a flow state of the bath surface by top, and the side in the temperature difference and the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end warmth clock of the temperature difference between the warm side in thermal average temperature and the other end, when the at least one out of the reference temperature range is determined as an abnormal flow condition of the bath surface.

[24]

The bath surface flow detection unit, in the cast molding, the plurality of side warmth installed so listed, along the width direction of the mold, and the side warmth in the one end, the side is installed right next to the one end of warmth, located on the other end side heat and measuring a temperature of the side is installed right next to the other end of warmth, and the temperature of the side of warmth in the one end, direct temperature between side temperature of warmth provided to the next difference value between the one end of the first and calculating the temperature difference, calculates the temperature on the side of warmth in the other end, and the right temperature between the temperature at the side of warmth provided to the next difference value, the second temperature of the other end car, the first temperature differential and a second comparing the temperature difference with the reference temperature range, respectively, to determine the flow state of the molten steel bath surface in a normal or abnormal.

[25]

The bath surface flow detection unit, wherein the first temperature differential and a second temperature difference both when incorporated into the reference temperature range, determining the bath surface flow state to normal, and at least one of the first temperature differential and the second temperature difference is based on when out of the temperature range, the bath surface flow control apparatus for determining the bath surface flow state as abnormal.

[26]

The flow control unit, the calculated temperature difference to determine the location of the side warmth out of the reference temperature range, and the calculated temperature difference control the operation of the magnetic field generating unit corresponding to the location and side warmth out of the reference temperature range and adjust at least one of a moving direction, moving speed and strength of the magnetic field.

[27]

The flow control unit, the calculated temperature difference with the reference to detect a difference between the temperature range, the calculated temperature difference determines whether less than or greater than the reference temperature range, and the calculated temperature difference and the reference temperature, adjusting the magnitude of the current applied to the magnetic field generating unit in accordance with the difference between the range and the calculated temperature difference is based on whether less than or greater than the reference temperature range, the same as the molten steel discharged from a nozzle provided in the mold direction or in the opposite direction to move the magnetic field in the magnetic field generating unit.

[28]

Analyzes the detection bath surface flow patterns in said flow detection unit, a group included in the flow pattern classification unit for classifying the one flow pattern type of a plurality of flow pattern types are stored, and the flow control unit in the flow pattern classification unit and a plurality of flow control type according to a plurality of flow pattern types stored is stored, to select one of the flow control type according to the flow pattern type of the classification of the plurality of the flow control type, and controls driving of the magnetic field generating unit do.

[29]

The flow pattern classification unit, the flow pattern-type storage unit of the plurality of flow pattern type is stored; In contrast to the bath surface temperature data from the bath surface flow patterns detected by the flow detecting unit and the group plurality of flow pattern types of the temperature of the stored data, any one of the detected bath surface flow form the group plurality of flow pattern types stored It includes; pattern classifying unit for classifying the flow pattern type.

[30]

The flow pattern a plurality of flow pattern types stored in the type storing portion is classified into different types of flow pattern types, depending on the temperature distribution in the bath-surface location by the temperature and the bath surface of the flow pattern types of the plurality of the bath surface flow due to defects that have a lower likelihood of at least one of a normal flow pattern, and a plurality of abnormal flow patterns that are likely caused by the bath surface flow defects.

[31]

The flow control unit, said flow pattern type storage unit a plurality of flow, depending on the pattern types by changing the control condition of the magnetic field generating unit, flow control type storage unit a plurality of flow control type are stored to control the bath surface flow stored in the .; In accordance with the classification type of flow pattern, flow control type selection unit for flow control of a plurality of types stored in the type storing portion flow control, selection of any one of the flow control type; In the flow control type selector in accordance with a selected type of flow control by controlling the power applied to the magnetic field generating unit, the electromagnetic field controller for controlling the moving direction of the magnetic field; and a.

[32]

The mold is positioned between the first and second long sides and the first long side and the second long sides facing each other provided, comprising a first and a second short side is installed's spaced apart from each other are facing, and the plurality of side warmth is the It is installed in the first and second long sides and the first and second short sides of the mold, respectively, the first and second center position of the long side direction of the mold a nozzle for discharging the molten steel into the mold is provided, the magnetic field generating unit is the first, and provided so as listed in the extending direction of the first long side, is provided so arranged in the first and second magnetic field generation part is installed so that symmetrical with respect to the nozzle, the extension direction of the second long side, with respect to the nozzle third and fourth magnetic field generating unit comprises the electromagnetic field controller is the first to fourth magnetic field generating unit connected to the flow selected by the flow control type selection unit is installed such that a symmetric According to a control type and controls the power applied to the respective portions of the first to fourth magnetic field generating first to fourth controls the moving direction of the magnetic field in the magnetic field generating unit, respectively.

[33]

The flow control unit is any of the first to fourth magnetic field generating and maintaining a magnetic field moving direction is negative, the detected bath surface flow patterns with a plurality of abnormal flow pattern if the classification is the detected bath surface flow patterns to normal flow pattern If one is classified, and controls the first to fourth magnetic field generator, each magnetic field of the moving direction of the bath surface of the detected flow pattern so that the normal flow patterns.

[34]

The flow control unit is applied to and in accordance with the magnetic field movement direction and the current density in the selected flow control type has first to fourth magnetic field generator each of the magnetic field movement direction, the first to fourth magnetic field generating unit, respectively that controls current density.

[35]

A method according to any one of claim 3 to claim 15 and claim 18 to claim 24, wherein the plurality of side warmth is provided spaced at equal intervals in a position higher than the molten steel bath surface is accommodated in the mold.

[36]

The warm side is provided in the height of less than 50mm from the bath surface.

[37]

A method according to any one of claim 3 to claim 15 and claim 18 to claim 24, the separation distance between the side warmth disposed in a fixed-width region of the template of the plurality of side warmth, which is located outside of the fixed-width region greater than the distance between the warm side being arranged to fluctuation region.

[38]

The plurality of side warmth is provided in the height of less than 50mm in the top and bottom from the bath surface of the molten steel.

[39]

The mold comprises a pair of short sides opposite to each other being provided with a pair of long sides and, on both sides of said long sides facing apart from each other,

[40]

The plurality of side warmth is provided on the long side.

[41]

Separation distance between the warm side being arranged on the fixed-width region that is 55 to 300㎜ preferred.

[42]

That the separation distance between the warm side being arranged on the variation region 10 to 50㎜ preferred.

[43]

Toward the outside from the center of the long side of the width direction, the separation distance between the side of the plurality of warmth is reduced.

[44]

The separation distance between the outer side warmth disposed in the fixed-width region is gradually decrease.

[45]

The separation distance between the outer side warmth disposed in the area variation is gradually increasing deceleration.

[46]

[47]

Bath surface flow control method according to the invention, by using a plurality of the warm side is installed to be listed along the width direction of the template, the process of measuring the temperature of the molten steel bath surface in the width direction of the plurality of positions; By relative analysis to the temperature according to each of the measured position, detects a bath surface flow patterns of the molten steel, and comparing the temperature values ​​measured by the plurality of side warmth with relatively normal or abnormal flow condition of the molten steel bath surface the steps of: determining a; And the operation of the magnetic field generating unit when the maintenance operations of the magnetic field generating unit installed in the outside of the mold to its present state and the flow state of the bath surface that is determined as abnormal if the flow state of the bath surface that is determined as normal controlled, by controlling the magnetic field, the process of the bath surface is adjusted such that the normal flow; includes.

[48]

By analyzing the temperature according to each of the measured relative position, the process of detecting a bath surface flow patterns of the molten steel is relatively compared with a plurality of temperature measurements, indicated by the relative height of each position of the molten steel bath surface, It comprises the step of detecting a bath surface of the molten steel flow pattern.

[49]

Method to determine the flow state of the molten steel bath surface in a normal or abnormal, comparing whether the calculated temperature difference between the temperature of the plurality of side warmth, respectively, wherein the plurality of calculated temperature difference each of which includes a reference temperature range and determines the flow state of the molten steel bath surface in a normal or abnormal.

[50]

Calculating the temperature difference between the temperature of the plurality of side warmth, respectively, the calculated plurality of temperature difference each step of the comparison whether or not included in the reference temperature range is, for each of the plurality of side warmth other remaining side calculating a temperature difference between the warm and includes the step of comparing with the reference temperature range.

[51]

Other remaining side warmth for the other remaining side warmth when included in the standard temperature range, both of the difference values ​​of the respective temperature and determine the bath surface flow to the normal state, the plurality of side warmth, respectively for each of the plurality of side warmth of the difference value and each temperature, the at least one difference value is outside the reference temperature range.

[52]

Process of determining a flow state of the molten steel bath surface in a normal or abnormal, the process of one of the plurality of warm-side, using a warm side are installed on both ends measure the temperature in real time; By comparing whether the calculated temperature difference between the side warmth in the both ends, and that the temperature difference respectively between side warmth located on the calculated both ends contains a reference temperature range, the flow state of the molten steel bath surface in a normal or abnormal include; step of determining.

[53]

Process of determining a flow state of the molten steel bath surface in a normal or abnormal is, of the plurality of side warmth, by using the side warmth provided on the warmth in the heart, the side provided on one end of warmth and the other end, the temperature in real time the process of measurement; Calculating a temperature difference between the warm side is installed to the temperature difference and the temperature and the other end of the warm side is located on the central side between the warmth provided to the temperature and the one end of the warm-side located in the center; Comparing the temperature difference between the side of warmth provided to the temperature and the one end of the side warmth in the center of the reference temperature range, and compares the temperature difference between the side of warmth provided to the temperature and the other end on the side of warmth in the center of the reference temperature range and the step of determining a flow state of the molten steel bath surface in a normal or abnormal; includes.

[54]

When the car temperature difference and a temperature between side warmth provided on the heat and the other end located in the center between the side warmth and side warmth provided on one end located in the center of both to be included in the reference temperature range and determining a flow state of the bath surface by top, an abnormal flow condition of the bath surface when one or more of the temperature difference between the side warmth and side warmth provided to the other end located on the temperature difference and the center between the side warmth and side warmth provided on one end located in the center, at least one is outside the reference temperature range It is determined by.

[55]

Process of determining a flow state of the molten steel bath surface in a normal or abnormal is the step of measuring the temperature in real time by using the plurality of the warm side; Process for calculating the average temperature of the warm side temperature of said plurality; Calculating a difference between the plurality of the side of the warm, the temperature of the warm side and the other end located on the difference between the temperature and the average temperature of the warm side is located on one end and said average temperature; It includes; process by comparing the temperature difference between the temperature of the warm side is located on the one side and the other side edge and the mean temperature and a reference temperature range, determining a flow state of the molten steel bath surface in a normal or abnormal.

[56]

Determining the normal flow condition of the bath surface when said average temperature and said one side warmth temperature between in the end cars and the average temperature and the temperature between side warmth located at the other end of the car all included in the reference temperature range, and the average temperature and the when at least one of the temperature difference between the temperature between the warm side, located on one end car and the average temperature of the warm side is located on the other end is outside the reference temperature range is determined as an abnormal flow condition of the bath surface.

[57]

Process of determining a flow state of the molten steel bath surface in a normal or abnormal, the process of one of the plurality of side warmth, the warmth measuring side, the temperature of the warm side is located on one side and the other end is located in the center in real time; The process of calculating the time-series average temperature of the warm side is located in the center; Process for calculating the calculated time-series average temperature and the temperature of the one side and the warm side to the other end in order, respectively; As compared to the reference temperature range, the temperature difference between the warm side, located on the calculated average temperature time series and one side and the other end, the steps of: determining a flow state of the molten steel bath surface in a normal or abnormal; includes.

[58]

According to calculate the side time series average temperature of the warm located in the center, and from the casting initially to discharge the molten steel in the mold measure the temperature on the side of warmth in the center, and calculating the thermal average temperature watch in real time, to said center located side after output clock warmth to the thermal time constant average temperature, using the respective temperature in the warm side to the one side and the other end determines the state of the molten steel bath surface flow.

[59]

The temperature difference and the temperature difference between both the reference temperature range between side warmth in the time-series average temperature and the other end on the side of warmth in the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end included when flow conditions for determining the top, and located on the temperature difference and the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end side warmth time series average temperature and the other end of the bath surface of the temperature difference between the warm side, located in, when the at least one out of the reference temperature range is determined as an abnormal flow condition of the bath surface.

[60]

And the step of determining a flow state of the molten steel bath surface in a normal or abnormal, one of the plurality of side warmth, and side warmth in the one end, side warmth is installed right next to the one end, the side located on the other end of warmth, the process of measuring the temperature of the warm side is installed right next to the other end; And the temperature of the warm side is located on the one end, in the process of calculating the temperature difference between the temperature of the warm side is installed right next to the first temperature difference between the one end; The temperature of the warm side is located on the other end, and a process for calculating a second temperature difference the temperature difference between the temperature of the warm side is installed right next to the other end; Comparing the first temperature differential and a second temperature difference, respectively, and the reference temperature range, the process of determining a flow state of the molten steel bath surface in a normal or abnormal; includes.

[61]

The first temperature difference and the second temperature difference when all the time to be included in the reference temperature range, determining the bath surface flow state to normal, and the first temperature difference and the second at least one of the temperature difference is outside the reference temperature range, the bath surface it is determined as abnormal flow conditions.

[62]

The reference temperature is a temperature difference value the cast defect rate being less than 80%.

[63]

The standard temperature range is preferably more than 15 ℃, not more than 70 ℃.

[64]

Processes in which the bath surface flow adjusted such that the normal, the process of the calculated temperature difference to determine the location of the warm side is outside the reference temperature range; The calculated temperature difference between the process for controlling at least one of to control the operation of the magnetic field generating unit corresponding to the location and side warmth outside the reference temperature range, the moving direction, moving speed and strength of the magnetic field; includes.

[65]

Wherein the process of the calculated temperature difference control the operation of the magnetic field generating unit corresponding to the location and warm side is outside the reference temperature range, detecting a difference between the calculated temperature difference and the reference temperature range, and the calculated temperature difference in the process to determine whether a is less than or greater than the reference temperature range; The process of adjusting the amount of current applied to the magnetic field generating unit according to the difference between the calculated temperature difference and the reference temperature range; It includes; the calculated temperature difference in the process of moving the magnetic field to the magnetic field generating unit in the molten steel discharge direction the same or opposite direction, from the nozzle installed in the mold depending on whether it is less than or greater than the reference temperature range.

[66]

The process of classification into any one type of flow pattern of the plurality of flow pattern types stored in the detected bath surface flow patterns; The process of the classification of the type of flow pattern types stored in a plurality of the flow control group and to select one selected flow control type; Include; process for controlling a magnetic field formed in the magnetic field generating unit installed in the outside of the mold to the selected flow control type.

[67]

The process of classification into any one of said flow pattern type of the bath surface of the detected flow pattern pre-stored plurality of flow pattern types, and storing classified to a plurality of types of flow patterns that can occur in the casting process; The process to prepare a group detected bath surface flow patterns and a plurality of flow pattern type is stored; Of the detected plurality bath surface flow patterns of flow pattern types of the previously stored temperature data in the step of classification by any one type of flow pattern; includes.

[68]

A plurality of flow patterns that are stored the group types include defects that have a lower likelihood of at least one normal flow pattern, with a high defect potential generated by the bath surface flow plurality unsteady flow pattern by the bath surface flow.

[69]

In controlling the magnetic field formed in the magnetic field generating unit to the classification flow pattern type of the plurality of the flow control type, select the flow control type respectively corresponding to each of the plurality of flow pattern types, and to the selected flow control type the power to the magnetic field generating unit is applied, and controls the magnetic field movement direction of the magnetic field generating unit.

[70]

In controlling the magnetic field formed in the magnetic field generating unit to the classification flow pattern type, the selected flow control type according to have the magnetic field movement direction and the current density that controls the magnetic field movement direction and the current density of the magnetic field generating unit do.

[71]

The mold is positioned between the first and second long sides and the first long side and the second long sides facing each other provided, comprising a first and a second short side is installed's spaced apart from each other are facing, and the plurality of side warmth is the It is installed in the first and second long sides and the first and second short sides of the mold, respectively, the first and second center position of the long side direction of the mold a nozzle for discharging the molten steel into the mold is provided, the magnetic field generating unit is the first, and provided so as listed in the extending direction of the first long side, is provided so arranged in the first and second magnetic field generation part is installed so that symmetrical with respect to the nozzle, the extension direction of the second long side, with respect to the nozzle and comprising a third and fourth magnetic field are installed so that symmetry occurs, by controlling the operation of the magnetic field generating unit, by controlling the magnetic field, there is the bath surface to flow adjusted such that the normal Standing, and controls the first to fourth magnetic field generating unit by controlling the power to be applied to each of the first to fourth movements of the magnetic field in the magnetic field generating section each direction according to the selected flow control type.

[72]

From the detected bath surface flow patterns, of a plurality of temperature measurements detected at a plurality of positions on one side and the other side respectively of the bath surface of the nozzle, both edges of the bath surface of the temperature range, bath surface center temperature between the lowest temperature and the highest temperature high and the temperature low, the amount by the difference between the edge temperature and the bath-surface center temperature of the normal flow pattern, and are classified as an abnormal flow pattern, the plurality of flow pattern types, in each of the temperature data of the plurality of flow patterns, the minimum temperature and the high temperature of the both edges of the bath surface for the temperature variation, the center bath surface temperature between the highest temperature low, by the difference between the both edges of the center temperature and the bath-surface temperature is classified into different abnormal flow pattern type.

[73]

Of the temperature value of the detected bath surface flow patterns, greater than or equal to the minimum temperature and the difference of bath surface temperature variations that group the temperature each center temperature of satisfying the standard deviation, and the bath-surface both edges is set between the maximum temperature, the bath surface both edges respectively, when the temperature and the central difference in the first and second temperature difference between the temperature respectively satisfy the reference value or less, the classification to the normal flow pattern, and the bath-surface temperature difference is out of the standard deviation, or the first and second temperature difference When each is less than the central temperature, or the at least one of the first and second temperature difference exceeds a reference value preset, to be classified as an abnormal flow pattern.

[74]

If the detected bath surface flow patterns are classified by any one of a plurality of abnormal flow pattern type, at least one of a temperature of the both edges of the detected bath surface flow pattern it is greater than the core temperature, the first to fourth magnetic field generating in the section, the two sides of the zone of the nozzle, by adjusting a magnetic field in the portion that the temperature of the edge in response to a large area compared with the magnetic field generating core temperature to move in the direction of the nozzle, and the molten steel flow velocity deceleration.

[75]

If and when the detection bath surface flow patterns are classified by any one of a plurality of abnormal flow pattern, at least one of a temperature of the both edges of the detected bath surface flow pattern is less than the core temperature, the first to fourth magnetic field generating in the unit, to adjust the magnetic field at the corresponding magnetic field generating unit located on a small area, the temperature is compared to a center temperature of the edges to move in the outward direction from the nozzle, and accelerates the flow rate of the molten steel.

[76]

The amount by which the difference in temperature between the temperature and the central temperature of the edge of the larger first to fourth by increasing the current density to be applied to at least any one of the magnetic field generating unit, thereby increasing the acceleration or deceleration force of the molten steel.

[77]

If the detected bath surface flow patterns which are classified into one of a plurality of abnormal flow patterns, the detected flow pattern bath surface if the difference value between the both edges of each of the temperature and said center temperature is less than the lower limit value of the maximum standard deviation,

[78]

The first to fourth by the different magnetic field in the direction of movement of the magnetic field generating unit, respectively, to rotate the molten steel.

Effects of the Invention

[79]

According to the embodiments of the present invention, by installing a plurality of side warmth on the upper side of the mold to detect the widthwise position by the temperature of the bath surface, the relative expressed by it, the bath surface flow patterns by the molten steel bath surface position is converted into a relatively high It is detected. In addition, the present evaluation method or criteria for determining the bath surface into a plurality of flow state, and by using any one of them to determine the flow state of the bath surface in real time. Further, it is possible by controlling the operation of the magnetic field generating unit in accordance with the bath surface flow state is determined in real time, to control the bath surface with the floating state does not cause a low defect or defect rate. Therefore, even if the mold flux to the molten steel bath surface is applied in the slab casting, the bath surface flow control method using the invention embodiments bath surface flow control apparatus according to this, and for detecting a flow of the bath surface in real-time can be controlled. Thus, by reducing the bath surface defects caused by the flow, and improve the quality of the main room.

[80]

Further, by installing a plurality of the warm side to the upper side of the mold to detect the widthwise position by the temperature of the bath surface, the relative expressed by them, and detects a bath surface flow patterns is converted into relative position by the height of the molten steel bath surface. Further, the classification of any one of the detected bath surface flow pattern group a plurality of flow pattern types are stored, and the category of the flow by controlling the in-field molding, according to the pattern type, the flow of the molten steel is being run cast defects likely little or no normal can be controlled so that the flow pattern.

[81]

In addition, in the embodiments of the present invention to install a plurality of spaced-apart side warmth in different distances from the fixed-width region and the variation region of the slab width in the copper plate to set the width of the front mold. This can be regardless of the setting of the cast in the width direction detecting a temperature of the molten steel, and the relative represented by this is converted into position by the relative height of the molten steel bath surface visible the bath surface shape.

Brief Description of the Drawings

[82]

1 is a view showing the bath surface flow control apparatus according to a first embodiment of the present invention installed on a template in concept.

[83]

Figure 2 is a top view showing a state in which side warm bath surface constituting the flow control apparatus according to the first embodiment in the short side each of the long sides and a pair of a pair of molds provided.

[84]

Figure 3 is a double roll flow pattern of the molten steel, Figure 4 is a view showing a single roll flow type.

[85]

5 and 6 is a view showing an example of a normal bath surface flow.

[86]

7 and 8 is a view showing an example of a flow of the bath-surface abnormality.

[87]

Figure 9 is a graph showing the defect rate of cast steel according to the temperature difference between the warm side.

[88]

10 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the first evaluation method the normal, determined as abnormal, and an abnormal condition.

[89]

11 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a second assessment to the normal, determined as abnormal, and an abnormal condition.

[90]

12 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a third evaluation method the normal, determined as abnormal, and an abnormal condition.

[91]

13 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a fourth evaluation method to normal, determined as abnormal, and an abnormal condition.

[92]

Figure 14 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the method of claim 5 with a normal, determined as abnormal, and an abnormal condition.

[93]

15 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the evaluation method of claim 6 to a normal, determined as abnormal, and an abnormal condition.

[94]

16 is a view illustrating a bath-surface flow control apparatus according to a second embodiment of the present invention.

[95]

17 and 18 is a diagram showing a mold with a plurality of side warmth and magnetic field generating unit is installed.

[96]

19 is a diagram showing the configuration of the screen Bullock bath surface flow control apparatus according to an embodiment of the invention.

[97]

20 is a top view of a plurality of side warmth provided on each of a pair of long sides and a pair of short sides of the mold.

[98]

Figure 21 is a visible to screen for a pair of long sides and a pair of short-side width bath surface flow patterns of the position-temperature relatively expressed by the detection in each of the measurement by a plurality of side warmth graph graph, Figure 22 is a 3 a one-dimensional visualization image.

[99]

Figure 23 is a top view showing a state installed on the long side and short-side side warmth provided each mold.

[100]

24 is a view illustrating a plurality of flow pattern types that are pre-stored or preset flow pattern in the type storage section in the embodiment;

[101]

25 is a view showing a double-roll type flow generated in the eighth flow pattern types shown in Fig.

[102]

26 is a view showing a single roll of the flow pattern in the seventh flow pattern types shown in Fig.

[103]

27 and 28 shows a first flow pattern type and a second flow pattern type of location-specific temperature distribution that is classified as a normal flow pattern in the embodiment of the present invention.

[104]

29 is a diagram illustrating a plurality of flow pattern types and thus the plurality of flow control according to the type that is pre-stored or preset the type of flow pattern storage section in the embodiment;

[105]

30 is a diagram showing the phases of two-phase alternating current applied to the magnetic field generating unit.

[106]

Figure 31 to Figure 34 is a view for explaining the flow direction and the rotating flow of the molten steel in accordance with the two-phase alternating current applied to the magnetic field generating unit.

[107]

35 is a flow chart for explaining the bath surface flow control method according to an embodiment of the present invention.

[108]

36 is a flowchart illustrating a method of detecting bath surface flow patterns in the bath surface flow control method according to an embodiment of the present invention.

[109]

37 is a flowchart illustrating a method of classifying the bath surface flow detected at the bath surface flow control method according to an embodiment of the invention as a flow type.

[110]

Figure 38 is a perspective view of the mold bath surface is visualized according to the exemplary modification of installed.

[111]

39 and 40 is a view illustrating a fixed-width region and a variation region of the mold is formed.

[112]

Figure 41 is a front view for explaining the arrangement of the warm side shown in Figure 38.

[113]

42 to 44 are diagrams for explaining the arrangement of the warm-side according to a modified example of the present invention.

[114]

45 is a plan view for explaining the arrangement of the warm side shown in Figure 38.

Mode for the Invention

[115]

With reference to the accompanying drawings will be described embodiments of the present invention; However, the invention is not limited to the embodiments set forth herein. Rather, be embodied in many different forms, but the embodiment of the present invention are also the teachings of the present invention to complete, in the invention to those of ordinary skill It will be provided to fully inform the scope. Same numerals in the drawings refers to the same element.

[116]

Typical casting equipment includes a nozzle disposed to supply the tundish, the tundish the molten steel for temporarily storing the molten steel located in the upper mold 10, a mold 10 which when supplied with molten steel from the nozzle 20 is cooled first in the mold, to be installed on the lower mold 10 spray cooling water to the semi-solidified cast steel drawn from the mold (10) and a secondary cooling zone to cool. Here, it may be configured of a plurality of segments laid secondary cooling which extends in the casting direction.

[117]

Tundish, nozzle 20, the secondary cooling zone, etc. are the same as that of a general casting equipment, and the description thereof will be omitted.

[118]

On the other hand, occurs the flow of a molten steel in the mold 10 by molten steel to be discharged through both the discharge port of the nozzle 20, so that means that the top surface of the molten steel and the molten steel bath surface flow occurs, the flow pattern of molten steel or the bath surface Therefore, the quality is determined two weeks convenience. Thus, by detecting the flow of intra-mold molten steel bath surface 10 in real time, it is necessary to control the flow of molten steel in real time. That is, when the bath surface flow in the cast steel casting species is determined as abnormal, it is necessary to normalize to control them.

[119]

Therefore, the present invention provides a bath surface flow control apparatus for controlling the flow and detecting the flow state of the intra-mold molten steel bath surface 10 in real time, and bath surface in accordance with the flow state.

[120]

[121]

1 is a view showing the bath surface flow control apparatus according to a first embodiment of the present invention installed on a template in concept. Figure 2 is a top view showing a state in which side warm bath surface constituting the flow control apparatus according to the first embodiment in the short side each of the long sides and a pair of a pair of molds provided. Figure 3 is a double roll flow pattern of the molten steel, Figure 4 is a view showing a single roll flow type. 5 and 6 is a view showing an example of a normal bath surface flow. 7 and 8 is a view showing an example of a flow of the bath-surface abnormality. Figure 9 is a graph showing the defect rate of cast steel according to the temperature difference between the warm side.

[122]

1, a casting plant including a bath-surface flow control apparatus according to a first embodiment of the invention the mold (10 on the mold 10, the mold 10 is cooled when supplied with molten steel from the nozzle 20 ) generating a magnetic field to form a magnetic field for flowing of a molten steel in the mold (10) width is provided spaced apart such that arranged in the direction, is provided outside the plurality of side warmth 100, the mold 10 for measuring a temperature in each of the the operation of the unit 500, the mold 10 within the received molten steel bath surface flow bath surface flow detection unit 200, the bath surface flow detection unit the magnetic field generating unit 500 according to the bath-surface condition detected in 200 for detecting the control and, by adjusting the bath surface flow, it comprises a flow control unit 400 for controlling so that the molten steel bath surface is in the form of a normal flow pattern.

[123]

In addition, 2 of the casting equipment is located above the mold 10, although not shown, and cooled to be installed on the lower side a tundish, a mold (10) for temporarily storing the molten steel jet the cooling water in the semi-solidified cast steel drawn from the mold and a primary cooling zone. Here, it may be configured of a plurality of segments laid secondary cooling which extends in the casting direction.

[124]

Tundish, nozzle 20, the secondary cooling zone, etc. are the same as that of a general casting equipment, and the description thereof will be omitted.

[125]

The mold 10 is cooled first in order to receive the molten steel supplied from the nozzle 20, and solidifying the molten steel to a predetermined shape of the product. This mold 10 is spaced apart, a distance between a distance of two long sides are spaced apart facing each other provided (11a, 11b) and two long sides (11a, 11b) as shown in Figures 1 and 2 each other, provided to face 2 comprises two short sides (12a, 12b). Here, the long side (11a, 11b) and short sides (12a, 12b) can be prepared by using copper, for example, respectively. Thus, the mold 10 has a predetermined space for receiving the molten steel is provided between the two long sides (11a, 11b) and two short sides (12a, 12b). In addition, the two longer sides (11a, 11b) and two short sides (12a, 12b) are nozzles 20 in a central portion of the forming mold 10 is provided. The molten steel is supplied from the nozzle 20 is a discharge flow is formed and fed to the symmetrical outward from the center portion of the mold 10 Possession certain flow phenomena according to the operating conditions. On the other hand, the molten steel is received in the mold 10 the upper end of the mold 10 to remain in a predetermined width, may be a mold flux is applied on the upper surface molten steel. This means that the top surface of the molten steel, the surface of the molten steel bath surface is the (meniscus).

[126]

A plurality of side warmth 100 measures the temperature of the contained molten steel or molten steel bath surface in the mold 10 during the current run. As a plurality of side warmth 100. This is shown in Figures 1 and 2, there is installed spaced apart from each other to be arranged in the width direction of the mold 10, wherein a plurality of side warmth 100 is the same of ± 50mm from the bath surface It is installed in height. Further, as the mutual separation distance between the plurality of warm side 100 is equal intervals, it may be arranged mutually remote to 100mm to 150mm. A plurality of warm side 100 is installed spaced apart from each other so that the list in each of a pair of long sides and a pair of short side in the width direction. And the warm side (100) there is provided at the upper mold 10 so as to be disposed in the bath surface, a pair of long sides (11a, 11b) and a pair of short sides (12a, 12b) of higher than the bath surface within 50㎜ in each It is provided at the position. Preferably warm side 100 is a higher position within 10mm upwardly from the bath surface, it is provided on the high point of 4.5mm and more preferably from bath surface.

[127]

In one embodiment using a thermocouple as a warm side 100, it is possible that various means to measure the temperature is not limited to this application.

[128]

Nozzles between when the molten steel is discharged from both the discharge port of the nozzle 20, the mold 10 the molten steel, and there is flow to the variable of the bath surface, wherein the blockage of both the discharge port of the nozzle 20 or not, the tundish and the mold 10 flow pattern of the molten steel and the bath surface by a variety of reasons, such as whether the control failure of the inert gas (e.g. Ar) to be supplied to whether the outside air a mixture of a sliding gate for controlling the communication of the 20, nozzle 20, nozzle 20, melting It changes that.

[129]

Does usually not occur clogging in both the discharge port of the nozzle 20, there is no mixing of the sliding gate, in the case there is no problem with the melting and inert gas control of the nozzle 20, the molten steel or the bath surface is the normal flow condition see. That is, when the molten steel is discharged from both the discharge port of the nozzle 20, the molten steel discharge flow a and hit the wall of the mold (10) a short side (12a, 12b), and then the molten steel is branched and down along the short sides (12a, 12b) nozzle from the flowing strong double roll (double roll) flow is generated (see Fig. 3 a, B, Fig. 5), it is branched to the upper side (upper) mold 10 short sides (12a, 12b) in the molten steel bath surface position 20 is directed in a direction. At this time, the molten steel discharge flow amount of the height of the bath surface by collision as the amount of the short side of the mold (12a, 12b) the edge is higher than in other regions (see Fig. 3, Fig. 5 and 6). At this time, the bath surface height and the amount of other areas or height difference does not cause a defect rate of the cast defect is the difference in height of the edge which is below the reference value. In other words, the flow of this liquid steel is a very stable flow conditions, the bath surface is suitable rate and temperature can be ensured or not a fault occurs, the flow state to be greater than the reference value.

[130]

However, other example, the tundish and the mold 10 in a sliding gate for controlling the communication of the nozzle (20) between or outside air is mixed into the nozzle 20 is out of control of the Ar amount to be supplied to the nozzle 20, melting, etc. if there is a problem, while a single roll that the flow (C) of the molten steel directed to the lower side from the discharge nozzle 20 occurs, the drift of the flow pattern (see Fig. 4). By such a flow is a slag (slag) incorporated in the molten steel due to a defect which occurs is generated.

[131]

As another example, when the occurrence of a discharge port blockage of both the discharge port of the nozzle 20, is formed in drift of molten steel badly, the vortex (VORTEX) form a flow or flow and the occurrence of, in either side as shown in this Figure 7 the height of the edge of bath surface is excessively high asymmetric flow is generated in comparison to the height of the other side edge bath surface (see Fig. 7 and 8). This flow pattern will greatly increase the comfort potential state defects.

[132]

The bath surface flow detection unit 200 according to the first embodiment analyzes the temperature measurements from a plurality of side warmth 100, it is determined whether the detected the bath surface flow as described above, detects bath surface flow is normal or abnormal . That is, the bath surface flow detection unit 200 compares the temperature measured values ​​measured in each of a plurality of side warmth 100, analyzes, and detects a bath surface flow patterns or conditions. That is, the relative comparison of the temperature measured values ​​measured in each of the plurality of warm side 100, and determines whether or not the current This bath surface flow state is normal or abnormal conditions, to detect the flow pattern. In particular, in the first embodiment of the present invention provides a plurality of evaluation method for evaluating the bath surface flow in the normal or abnormal.

[133]

Magnetic field generating unit 510 to form a magnetic field to the molten steel to flow by the magnetic field is controlled by the flow control unit 400. The magnetic field generating unit 510 includes a plurality of magnetic field generation section (510a, 510b, 510c, 510d). To Figure 1, the unit magnetic field generating (510a, 510b, 510c, 510d) is provided with a plurality there is provided outside the mold 10, in the embodiment section of four magnetic field generating (510a, 510b, 510c, 510d) provided to be installed on the outer long side (11a, 11b) of the pair of mold 10. More specifically, there is the outer two magnetic field generating unit (the first magnetic field generation section (510a), the second magnetic field generating unit (510b)) of the first long side (11a) installed, a first magnetic field generation section (510a) and a second magnetic field generating unit (510b) is provided so as listed along the extending direction of the first long side (11a). In addition, the second long side (11b) outside the two magnetic field generation section (hereinafter referred to as the third magnetic field generating portion (510c), a fourth magnetic field generation section (510d)), and is installed in, the 3rd magnetic field generating portion (510c) the fourth magnetic field generation section (510d) is provided so as listed along the extending direction of the second long side (11b). That is, the mold first magnetic field generation section (510a) and the third magnetic field generating portion (510c) (10) in one direction relative to the nozzle 20 which is located in the center in the width direction is to face on the outer side of the mold 10 installed and, when the second magnetic field generating unit (510b) and the fourth magnetic field generation section (510d) in the other side direction is provided so as to face.

[134]

The above-described first to fourth magnetic field generating unit (510a, 510b, 510c, 510d) each of which I have the same configuration and shape, each of the mold 10 a long side (11a, 11b) a core member extending in a direction (511a in , the 511b, 511c, 511d), each of the core members (511a, 511b, 511c, are provided so as to wound around the outer peripheral surface of 511d), arranged spaced apart from each other along the extending direction of the core member (511a, 511b, 511c, 511d) and a plurality of coil members (512a, 512b, 512c, 512d). Here, coil members (512a, 512b, 512c, 512d) is a member of the coil which is wound in a spiral shape, one of the core members (511a, 511b, 511c, 511d) a plurality of coil members on the (512a, 512b, 512c , 512d) are provided.

[135]

Magnetic field generating unit 510 according to an embodiment of the present invention to provide a common EMS, is to control the direction of movement, rotation, acceleration and deceleration of the magnetic field is not particularly limited, the same as the driving method of the conventional EMS.

[136]

[137]

The flow control unit 400 to control the power or current applied to the magnetic field generating unit 500 in accordance with the bath surface flow patterns and adjust the molten steel in the magnetic field to be a normal flow pattern. In other words, the flow control unit 400 controls each operation a magnetic field generation section (510a, 510b, 510c, 510d) in accordance with the bath surface flow detected at the bath surface flow detection unit 200, the flow direction and flow rate of the molten steel control, when this occurs bath surface to flow pattern and temperature in the magnetic field generated in accordance with differences in bath surface portion (510a, 510b, 510c, 510d) each application of a magnetic field moving direction by controlling the current, the strength (strength) and at least one of the moving speed controls.

[138]

For example, the molten steel in the mold 10, a long side (11a, 11b) magnetic field to the mold 10, the short side of moving horizontally in a direction (12a, 12b) the direction from the nozzle 20 is located toward, that the nozzle 20 moved in the discharge direction and the opposite direction, the application method causing a molten steel flow to impart a braking force to the molten steel discharge flow from the nozzle 20. Typically these flow control "EMLS", "EMLS mode", will be labeled as the magnetic field applied by the "EMLS mode. In the case of forming a magnetic field in the magnetic field generating unit 500 in this EMLS mode, the intra-mold molten steel bath surface 10 it is possible to attenuate the molten steel flow.

[139]

As a method for imparting the accelerating force of the molten steel discharged from the other magnetic field-applied method, a nozzle 20, a short side of the mold 10, the magnetic field moving horizontally along the long side direction of the mold 10 from nozzles 20 (12a , 12b) when the direction in other words, to move in a direction, as the molten steel flow method by the movement of the magnetic field to the molten steel discharge direction and the same direction of the nozzle 20, to impart the accelerating force to the molten steel discharge flow, normal, "EMLA", "EMLA mode "," is referred to as a magnetic field applying method according to the EMLA mode when forming a magnetic field in one of these EMLA mode above the magnetic field generating unit 500, the molten steel discharge flow from the nozzle 20 are accelerated, so that the discharge current is mold 10 the short side and impinge on the wall of the (12a, 12b), and then the molten steel is short sides (12a, 12b) the according branches to the vertical, it is branched to the upper side (upper) mold 10 the short side in the molten steel bath surface ( from 12a, 12b) the position facing the nozzle 20 direction .

[140]

In a method for the other magnetic field-applied method is to horizontally rotate the molten steel mold 10 around the nozzle 20, more specifically, the magnetic field moving horizontally along the long side (11a, 11b) direction of the mold 10 It is a method that causes a molten steel flow moving in a direction contrary to each along the relative long sides and, for rotation in the horizontal direction along the solidifying surface. This is referred to as the normal "EMRS", "EMRS mode", "magnetic field-applied method according to the EMRS mode.

[141]

Description of the applied magnetic field, such as the above-described EMLS, EMLA, EMRS method will be described in greater detail when discussing the second embodiment will be described below.

[142]

[143]

Hereinafter will be described how to control the flow from the flow control unit according to the evaluation method and evaluation results of the bath surface flow of the bath surface in the flow detection unit according to the first embodiment of the present invention.

[144]

A pair of long sides of the mold 10, as shown in a plurality of side warmth 100 Fig. 1, (hereinafter, a first long side (11a), the second long side (11b)) and a pair of short sides ( claim is provided along each of the extending direction of one short side (12a) and a second short side (12b)). In the first embodiment, first, and the 7-side warmth provided along the extending direction of the first and the second long side (11a, 11b), the one side of warmth is provided in each of the first and second short sides (12a, 12b). In Figure 1 the first and the second long side (11a, 11b) Nos. 1 to 7 described along each of the extending direction is a number to refer to a plurality of the warm side 100, respectively. That is, the first and the second long side (11a, 11b) a plurality of warm side 100 is provided in each mold 10 patients in the first to seventh side warmth for example to the right to the left. Further, the first and second short sides (12a, 12b) a plurality of warm side 100 is provided in each of the mold is called the eighth side warmth. According to the arrangement of the plurality of side warmth, the first and the second long side (11a, 11b) in each, or the direction slab width, the side located at the both edges or both ends of warmth is the first and the seventh side warmth, the center position side warmth which is a fourth side warmth.

[145]

The first embodiment, as one example, the first and the second long side (11a, 11b), and the 7-side warmth provided on each of the one side of warmth provided on respective first and second short sides (12a, 12b) It has been described that. However, it not limited to this, the first and the second long side (11a, 11b) to may be a side warmth installed in number exceeding less than 7, or 7, the first and second short sides (12a, 12b) respectively, It may be a plurality of side warmth installed in each.

[146]

As described above, the plurality of side warmth 100 is installed on the first and the second long side (11a, 11b) and first and second short sides (12a, 12b) of the mold (10), each location-specific temperature a to measure, it is different, the temperature is measured according to the height of the bath surface. That is, the bath surface height differs by location due to the sloshing of a molten steel in the mold 10, the temperature measured at the relatively high position the height of the bath surface is higher than the temperature values ​​at different locations. This is because, the closer the distance between the height and side warmth 100 of the molten steel bath surface, a high temperature measured at the warm side 100, a low interval is farther temperature measured at the warm side (100). When explain this in other words, to measure the temperature in real time, and because jyeotgi close to one side of warmth when the measured temperature from 100 rises higher the bath surface height bath surface is the one side warmth 100, the one-side warmth If the measured temperature at 100, the falling lower the bath surface height of the bath surface is because the one side and away warmth 100. Accordingly, it is to detect the shape of the entire bath surface (or form) using the difference of the measured temperature at a plurality of side warmth 100. That is, to indicate the temperature value measured at a plurality of side warmth 100, a width disposed arranged in the width direction of the direction or the bath surface of the mold 10 by location, so the temperature is dependent on the height of the bath surface, the relative said temperature value expressed as compared with, it can be seen the relative height of the bath surface. Thus, as expressed by relative comparison of the measured temperature values ​​from a plurality of warm side 100, it is possible to determine the position by the height of the bath surface with a relatively, it is possible to detect the bath surface flow patterns.

[147]

Then, when the graph of the first and the temperature of the position in the two respective longer sides (11a, 11b) the direction of the mold 10, for example, the visible, as shown in Fig. 3, 4, 5, and 7 can do. That is, by using the first and second and the temperature of the position at each long side (11a, 11b) direction, the first and the temperature of the location in each of two short sides (12a, 12b) the direction of the mold 10 , for example, Fig. 3, can be visualized as shown in Fig. 4, 5 and 7, which can be displayed (display) on the display so that the operator can see.

[148]

On the other hand, if the molten steel is discharged from the nozzle 20, flows in both the lateral direction and about the nozzle 20, lateral to flowing molten steel mold 10 branches to the molten steel a vertical direction along the inner wall and collision or impingement do. By the molten steel flow by the discharge of such a molten steel, the molten steel top surface That is, the bath surface to flow, so that changes the height of the bath surface flow. That is, according to the flow pattern of molten steel, becomes the flow of the bath surface varies, whereby the position-specific bath surface height is determined by. Then, the defective generation rate is dependent on the flow of the molten steel bath surface or the flow state of the bath surface can be detected according to the location-specific temperature of the bath surface.

[149]

In the present invention, depending on the cast defect rate according to the temperature distribution in the bath surface, and determines the bath surface flow or temperature distribution in the bath surface of a normal or abnormal state. More specifically, in the exemplary embodiment of the present invention and determining the temperature distribution in the bath surface a defect rate is not more than 0.8% of the normal flow conditions of the bath surface, of the temperature distribution in the bath surface bath surface unsteady flow of the defect rate exceeded 0.8% state a judgment. Then, the temperature of the bath surface is named the defect rate is not more than 0.8%, the reference temperature range.

[150]

, It was performed multiple times slab casting experiment for determining the reference temperature range for judging the normal or abnormal state of the bath surface flow. That is, it was different from the temperature distribution in the bath surface, and calculates the defect rate of the cast molded in the condition thereof.

[151]

The defect ratio is 0.8 bath surface temperature distribution having the below there is a case a number of temperature distribution, largely measured from each of the long side (11a, 11b) a plurality of side warmth 100 is arranged to be listed in the direction of the mold 10 the temperature and the relative comparison, a plurality of side warmth 100 each relative temperature difference is more than 15 ℃, when 70 ℃ or less, a cast defect rate of 0.8% or less. If this in other words, a plurality of warm side 100 of the plurality of temperature values ​​measured from each of, the difference between the maximum temperature and the minimum temperature of 15 ℃, when 70 ℃ or less, than the cast defect rate of 0.8%. In other words, looking at 0.8% or below bath surface temperature distribution having the defect rate, according to the temperature measured from the long side (11a, 11b) a plurality of side warmth 100 is arranged to be listed in a direction, each of the mold 10, the maximum the difference in temperature and the minimum temperature is less than 15 ℃, 70 ℃.

[152]

Therefore, the relative comparison with a plurality of sides, respectively the temperature of the warm (100), by each of the temperature difference for a plurality of side warmth 100 determines whether or not satisfy the standard range of temperatures, and the normal flow state of the bath surface compared or to judge as abnormal, named as first evaluation method, wherein the reference temperature range named as a first reference temperature range. Wherein the first reference temperature range used in the first evaluation method is not less than 15 ℃, less than 70 ℃. That is, according to the first evaluation method, when a plurality of warm side 100 respectively of the relative temperature difference is more than 15 ℃, when less than 70 ℃, the bath surface is determined to normal flow state, it leaves a judgment of abnormal flow conditions. Other words, in each of the temperature at the plurality of side warmth 100, and the temperature on the side of warmth with the maximum temperature, the bath surface is the difference between the temperature at the side of warmth with a minimum temperature at which more than 15 ℃, less than 70 ℃ temperature distribution and to the first reference temperature range.

[153]

Further, in addition to the first evaluation method described above in evaluation method to judge the normal or abnormal in the bath surface flow, further suggested the five evaluation method of the second to sixth evaluation method the reference temperature range to be used for evaluation in each of the 2 to 6 it will be named as the reference temperature range.

[154]

That is, it is determined in the slab casting species, it referred to below, in which the first to sixth evaluation method any one of the evaluation methods of the bath surface to flow by using a state of the normal or abnormal.

[155]

10 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the first evaluation method the normal, determined as abnormal, and an abnormal condition. 11 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a second assessment to the normal, determined as abnormal, and an abnormal condition. 12 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a third evaluation method the normal, determined as abnormal, and an abnormal condition. 13 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by a fourth evaluation method to normal, determined as abnormal, and an abnormal condition. Figure 14 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the method of claim 5 with a normal, determined as abnormal, and an abnormal condition. 15 is a graph showing an example of a state in which control to normal when it is determined a flow state of the bath surface by the evaluation method of claim 6 to a normal, determined as abnormal, and an abnormal condition.

[156]

[157]

Will be described below, the first to sixth evaluation method of the first embodiment method for detecting the bath surface flow conditions in other ways in the Examples and the normal or abnormal determination process flow of the bath surface using the same, the flow control method using a.

[158]

For convenience of description, and are 7-side warmth (101, 102, 103, 104, 105, 106, 107) provided along the long side direction of the mold 10, to the side of warmth at the right end from the side of warmth at the left end the first to seventh side warmth (101, 102, 103, 104, 105, 106, 107) termed, and the first to seventh side warmth (101, 102, 103, 104, 105, 106, 107) respectively, the measured temperature in and named as the first to seventh temperature.

[159]

The first evaluation method, if satisfied in, the relative temperature difference between the first reference temperature range (a range from 5 ℃, 70 ℃) to each of a plurality of side warmth (101, 102, 103, 104, 105, 106, 107) the current bath surface and it determines a flow state to normal. That is, it is determined the first to seventh warm side (101, 102, 103, 104, 105, 106, 107), each of the relative temperature difference is more than 15 ℃, when less than 70 ℃, bath surface flow to normal. In other words, calculating the temperature difference between the respective temperatures of the plurality of side warmth (101, 102, 103, 104, 105, 106, 107), and that the the calculated plurality of temperature differences, each with the reference temperature range comparison whether, and by calculating the temperature difference between the other remaining side warmth for each of the plurality of side warmth (101, 102, 103, 104, 105, 106, 107), comprises the step of comparing with the reference temperature range .

[160]

More specifically, the first side warmth 101 and the second to seventh side warmth (102, 107) each of the temperature difference, the second side warmth 102 and the first side warmth 101 and the third to a seventh side warmth (102, 107) each of the temperature difference, the third side warmth 102 and the first side warmth 101, a second side warmth 102, and the fourth to seventh side warmth (102, 107) each of the temperature difference, the fourth side warmth 104 and the first side warmth 101 to the third side warmth 103 and fifth to seventh side warmth (105, 107), each temperature difference, the fifth side warmth 105 and the first side warmth 101 to the fourth side warmth 104, a sixth side warmth 106, a seventh side warmth 107, each temperature difference, and the sixth side warmth 106 and the first warm side 101 to the fifth warm side 105, a seventh side warmth 107 calculates the respective temperature differences, and comparing each of the temperature difference with the reference temperature.

[161]

At this time, the plurality of side warmth (101, 102, 103, 104, 105, 106, 107) when the relative temperature difference at each meet the first reference temperature, and determine the bath surface flow state to the normal, the first reference temperature range If it is determined out of the normal. That is, as shown in Figure 10, when compared to a plurality of side warmth 100, respectively, the temperature of the relatively, the temperature difference is determined as a steady flow state if more than 15 ℃, 70 ℃ or less, more than 70 ℃, 15 If less than ℃ judges as abnormal. Then, the bath surface flow state when it is determined as abnormal, and controls the operation of the magnetic field generating unit 500 in accordance with the bath surface flow patterns, a plurality of side warmth each (101, 102, 103, 104, 105, 106, 107) the relative temperature difference between the bath surface thereby normalizing the flow such that more than 15 ℃, less than 70 ℃. In this case, by comparing the temperature measurement from each of the plurality of side warmth (101, 102, 103, 104, 105, 106, 107) relative, looking at the bath surface position of the temperature difference is greater than the less than 15 ℃ or 70 ℃, to the position to control the operation of the magnetic field generating unit (510a, 510b, 510c, 501d) thereby normalizing the bath surface corresponding to the flow. Increase in the current applied to the magnetic field generating unit (510a, 510b, 510c, 501d), and reduction in size is adjusted according to the relative temperature difference.

[162]

For example, the cast in the continuous casting, as shown in FIG. 10, slab casting of a first section (T1) a plurality of first to seventh side warmth (101, 102, 103, 104, 105, 106 to, yeoteuna 107) below the first to seventh relative temperature difference or more, 70 ℃ 15 ℃ between the temperature measured by, the first section (less than the first to sixth relative temperature difference is 70 ℃ exceeds or 15 ℃ between the temperature after T1) It was. At this time, the bath surface flow detection unit 200 detects a bath surface flow patterns in the second period (T2), it determines the current flow in the bath-surface abnormality. And the flow control unit 400 to control the operation of the bath surface flow detection unit 200 bath surface flow abnormality judgment and, magnetic field generating unit 500 according to the bath surface flow in the form of in the first to the relative temperature between the seventh temperature the difference is such that more than 15 ℃, less than 70 ℃. Therefore, the third period (T3) in the bath surface flow state is normal.

[163]

For example, the temperature measured from a plurality of side warmth (101, 102, 103, 104, 105, 106, 107) compared to live relatively in the second section of Figure 10 (T2), and converts it to a bath surface height When imaged by may be the same as FIG. That is, in the time, the right end than the temperature of the first side warmth 100 located at the left end of the temperature between the plurality of side warmth (101, 102, 103, 104, 105, 106, 107) hayeoteul relative comparison with the 9 is a high-side temperature of the warm (100), where the temperature difference exceeds 70 ℃. When this is converted into imaged bath surface height, as shown in FIG. 7 is not symmetrical relative to the bath surface the center, for example, a high state is asymmetric bath surface height of the right end of more than a reference height than the bath surface of the left end.

[164]

Asymmetric flow in this second interval (T2), the molten steel bath surface is doedaga maintain the normal flow pattern to the first period (T1), the nozzle 20 is caused clogging of the discharge port strong on the right side about the nozzle 20 because drift is generated, and it was a weak flow generated in the left direction. If this abnormal yudongil, by bath surface flow control unit 400 may further increase the deceleration force than before the adjustment by increasing the current applied to the second and fourth magnetic field generating unit (510b, 510d) located on the right side of the nozzle 20 lowering the strong flow, lowering the current applied to the located corresponding to the left side of the relatively weak flow generating nozzle 20, the first and third magnetic field generating unit (510a, 510c), reducing the deceleration force than before the adjustment by thereby increasing the flow. In the third period (T3) in the bath surface flow state it is normal.

[165]

On the other hand, it is a strong drift occurs on the left side of the nozzle 20, when the weak flow in the right direction occurs, the bath surface flow control unit 400 on the left side of the nozzle 20, the first and third magnetic field generator ( by further increasing the deceleration force than before the adjustment by increasing the current applied to 510a, 510c) lowering the strong flow, in response to the left of the relatively weak flow generating nozzle 20, the second and fourth magnetic field generating unit ( lowering the current applied to 510b, 510d), thereby increasing the flow by reducing the deceleration force than before the adjustment. In the third period (T3) in the bath surface flow state it is normal.

[166]

[167]

The second evaluation method a plurality of side warmth (101, 102, 103, 104, 105, 106, 107) of, by comparing the temperature difference between the side warmth in the both ends as to determine the flow condition, is located on either side end of the side temperature difference between the warm over 15 ℃, when less than 70 ℃ a judgment of the normal flow state. That is, it determines the bath surface flow state to normal, 15 when the difference between the temperature and the side temperature of the warm (107) of the right end of the side warmth 101 of the left end of a range from 15 ℃, 70 ℃ days during slab casting ℃ If less than, greater than a 70 ℃ it is determined as abnormal.

[168]

For example, as shown in Figure 11, slab casting of a first section (T1) to the difference between the temperature of the first side warmth 101 temperature and the seventh side warmth 107 located at the left end over 15 ℃, yeoteuna below 70 ℃, the can be a first interval (T1) after the first warm side 101 and the seventh temperature greater than the temperature difference between the side warm 70 ℃ 107, or less than 15 ℃. A second section (T2) at a first side warmth 101 temperature and the seventh side warmth 107 temperature difference is more than 70 ℃ between the, or the case 15 ℃ less than, the height difference between the both edges of the bath surface excessively large it seems an asymmetric flow conditions. At this time, the bath surface flow detection unit 200 is a second period (T2) determines the bath surface flow as unsteady and the flow control unit 400 in the second section (T2) at the control the operation of the magnetic field generating unit 500 to the first side and the temperature difference between the warm (101) temperature and a seventh side warmth 107 such that more than 15 ℃, less than 70 ℃, this third period (T3) in the bath surface flow state is normal. That is, the first side warmth 101 temperature and the seventh side through a temperature comparison between the warmth 107, identify the location and weak flow is relatively strong drift occurs caused location, and thus a plurality of the magnetic field of the by controlling the generating unit (510a, 510b, 510c, 501d) separately, which increases or decrease the flow. In the third period (T3) the difference between the first temperature and the ninth temperature is the normal flow state that is more than 15 ℃, less than 70 ℃.

[169]

A third evaluation method the plurality of side warmth (101, 102, 103, 104, 105, 106, 107) wherein the cast in the width direction center or the mold long sides (11a, 11b) the temperature of the side warmth 104 is located in the center in and, using the difference between the respective temperatures each side warmth in the end (101, 107) determines the bath surface flow conditions. For example, when that seven side warmth (101, 102, 103, 104, 105, 106, 107) installed side warmth which is located in the center of the cast in the width direction center or the mold long sides (11a, 11b) has a fourth side when said warmth 104, a first side warmth 101 temperature and the fourth side of warmth over the temperature is 15 ℃ difference between the 104 and below 70 ℃, a seventh temperature and a fourth side warmth 107 If the difference between the temperature of the warm side 104 is more than 15 ℃, 70 ℃ or less is determined as a normal flow state. Conversely fourth side warmth 104 and the any one of the temperature difference between the first temperature difference between the side warmth 101 and the fourth side warmth 104 and the seventh side warmth 101, one not satisfy the third reference temperature range If it is determined as abnormal flow conditions.

[170]

12, the cast steel cast a first section (T1) to the left end on the side of the warmth of the first side warmth 101 and the core side warmth (the fourth side warmth 104) of the temperature difference and, on the right end side warmth in the seventh warm side 107 and the core side warmth (warm fourth side 104) is less than 15 ℃, 70 ℃ temperature difference. However, in the second period (T2) from the first side warmth 101 and the fourth side warmth than 104, the temperature difference over 15 ℃, 70 ℃ between and, the seventh side warmth 107 and the fourth side warmth (104 ) it may be between the temperature difference exceeds 70 ℃. In this case the height of the bath surface of the right edge is a high asymmetric flow conditions over criteria than the height of the left edge of the bath surface. At this time, the bath surface flow detection unit 200 is a second period (T2) determines the bath surface flow as unsteady and the flow control unit 400 in the second section (T2) at the control the operation of the magnetic field generating unit 500 to, than before the adjustment by increasing the current applied to the located on the right side relative to the nozzle 20, which is a strong drift generating the second and fourth magnetic field generating unit (510b, 510d) lowering the strong flow, by further increasing the deceleration force, by lowering the current applied to the relatively weak in the flow corresponds to the left side of the generated nozzle 20. the first and third magnetic field generating unit (510a, 510c), reducing the deceleration force than before the adjustment, thereby increasing the flow . Thus, the seventh side of the temperature difference between the warm (107) temperature and a fourth side warmth 104 is not more than, less than 70 ℃ 15 ℃, the height of the bath surface, and this symmetry, the bath surface flow is normal.

[171]

For example, the second interval (T2) at a first side warmth 101 and the fourth side warmth 104 temperature difference less than 15 ℃, 70 ℃ between and, the seventh side warmth 107 and the fourth side warmth (104 ) may be between the temperature difference is less than 15 ℃. In this case the height of the bath surface of the right edge is a low flow condition is asymmetrical low unsteady flow conditions below a reference height relative to the left edge of the bath surface. Thus, the flow control unit 400 lowers the current applied to the located corresponding to the right side of the relatively weak flow generating nozzle 20, the second and fourth magnetic field generating unit (510b, 510d), a sense than before the adjustment by decreasing the speed, to increase the flow, or by reducing the current applied to the located on the left side of the nozzle where the relatively strong drift occurs first and third magnetic field generating unit (510a, 510c), more the deceleration force than before the adjustment It lowers the strong flow by reducing.

[172]

Wherein the temperature between the first side warmth 101 temperature and the fourth side warmth or less, or 104, the temperature difference is less than 15 ℃, 70 ℃ between the seventh side warmth 107 temperature and the fourth side warmth 104 of the a car has been described, for the exceeding 70 ℃, or less than 15 ℃ example. But, on the contrary between the seventh side warmth 107 temperature and the fourth side warmth 104 Temperature difference below 5 ℃ or less, 70 ℃ or, between the first side warmth 101 temperature and the fourth side warmth 104 of the temperature difference exceeds 70 ℃, or may be less than 15 ℃. Or first side temperature difference between the warm (101) temperature and a fourth side warmth 104, and the seventh temperature difference in between the side warmth 107 temperature and the fourth side warmth 104 exceeds 70 ℃ or It may be less than 15 ℃. In both it is judged as an abnormal flow condition case, the flow control unit 400 to respectively control the operation of first to fourth magnetic field generating unit (510a, 510b, 510c, 501d) in the same manner as described, bath surface the normalization of the flow.

[173]

The fourth evaluation method using the mean temperature and, each end side of the warm temperature of the temperature difference between the warm side of the plurality (101, 102, 103, 104, 105, 106, 107) determines a flow state of the bath surface. That is, when both ends of both side warmth temperature difference between each of the temperature and the average temperature of the fourth reference temperature range of more than 15 ℃, 70 ℃ or less is determined as a steady flow state.

[174]

For example, the average of the temperature of the seven side warmth (101, 102, 103, 104, 105, 106, 107) is to that installation, seven side warmth (101, 102, 103, 104, 105, 106, 107) temperature and, located in one end a first side warmth 101 and the temperature difference between the average temperature, which is located to the other end of the seventh side warmth 107 and more than 15 ℃ both the temperature difference between the average temperature, when 70 ℃ or less, normal a judgment of state. In contrast, seven side warmth (101, 102, 103, 104, 105, 106, 107) the average temperature of the temperature and of the first side warmth 101 and the temperature difference and the average temperature between the average temperature and the seventh side warmth ( any one of the temperature difference between the 107), even if you do not satisfy the fourth reference temperature range, a judgment of an abnormal flow condition.

[175]

For example, the temperature difference between the first period (T1) to the first to seventh side warmth average temperature of the first side warmth 101 of (101, 102, 103, 104, 105, 106, 107) during the slab casting and the average temperature and the seventh side both the difference temperature between the warm (107) is at least 15 ℃, less than 70 ℃, the second interval (T2) in excess of 70 ℃ in, the nozzle 20 bath surface the bath surface height in the left-right than may be highly unsteady flow state (see Fig. 13). Therefore, bath surface flow detection unit 200 is the first and the third magnetic field generated on the left side interpret this as an abnormal flow condition, and to control the operation of the magnetic field generating unit 500, the bath surface height relatively higher nozzle 20 by reducing the current applied to the portion (510a, 510c), to lower the flow.

[176]

13 The temperature of the eoteuna only shown in one temperature on the side of warmth in the side heat of the overall average temperature and the both ends, and one of the side warmth also is shown in the same way, the temperature difference between the average temperature is detected in real time.

[177]

Wherein in the all is not limited, but in the second interval difference average temperature and the temperature between the first side warmth 101, the temperature difference and the average temperature and the seventh side warmth 107 between described as exceeding both 70 ℃, this 15 ℃ It may be less than the abnormal state. In addition, the average temperature and the temperature between the first side warmth 101 temperature difference 15 ℃ or more, 70 ℃ or less, or the average temperature and the seventh side warmth 107 between the car can not exceed less than 15 ℃ or 70 ℃, wherein a judgment of abnormality. Conversely, it is possible to average temperature and the temperature between the seventh side warmth 107 temperature difference 15 ℃ or more, 70 ℃ or less, or the average temperature of the first side warmth 101 between the difference exceeds the less than 15 ℃ or 70 ℃, wherein a judgment of abnormality.

[178]

The fifth evaluation method includes a plurality of side warmth (101, 102, 103, 104, 105, 106, 107) wherein the cast in the width direction center or mold 10 long side (11a, 11b) side warmth (104 located in the center of ) time series average temperature and the warm side in the both edges (101 and 107) of the bath surface and determines the flow state using the respective temperature difference. That is, it is determined in each end side warmth (101 and 107) when all over 15 ℃, 70 ℃ equal to or less than the difference between the time-series average temperature of the warm side (104) located in each of the temperature and the center steady flow state. On the other hand, of the difference between the time series of side warmth 104 it is located in the center average temperature and one end side of the temperature difference and the time series of side warmth 104 is located in the center average temperature-side temperature of the heat of the other end between the heat of which does not satisfy any of the fifth reference temperature range, a judgment of an abnormal flow condition.

[179]

For example, cast or mold a long side (11a, 11b) located in the center of the fourth side warmth 104 of the time-series average temperature and one side to the temperature difference between the temperature of the first side warmth 101 and the fourth side warmth (104 edge of the ) of the time-series average temperature and the temperature between the temperature of the warm side of the seventh (101) located at a side edge of the difference determines whether or not all of at least 15 ℃, less than 70 ℃, it is determined whether normal or abnormal flow of the bath surface.

[180]

More specifically, it located in the center of the fourth side warmth 104 of the time-series average temperature in the first-side temperature difference between the temperature of the warm (101) and a fourth side warmth 104 of the time-series average temperature and the seventh side warmth When the temperature difference between the temperature of 101, a first time period (T1) is up to or less than 15 ℃, 70 ℃ (see Fig. 14). However, the second period (T2), a fourth side warmth 104 of the time-series average temperature of the first side warmth 101, the temperature difference and the between the temperature of four side warmth 104 of the time-series average temperature and the seventh side warmth in 101 to a temperature between the temperature difference exceeds 70 ℃, bath surface flow detection unit 200 determines it as an abnormal flow condition. And the flow control unit a time series average temperature of at least the control of any one of the operation, the fourth side warmth 104 of the first to fourth magnetic field generating unit (510a, 510b, 510c, 501d) through (400) and the temperature difference between the warm first side 101, such that more than 15 ℃, less than 70 ℃.

[181]

Wherein in is located in the center in the second region fourth side warmth 104 of the time-series average temperature of the first side warmth 101, the temperature difference and the fourth side warmth 104 of the time-series average temperature and the seventh side between warmth 107 may be between the temperature difference has been described by exceeding all 70 ℃, abnormal conditions both not limited to less than 15 ℃.

[182]

The fourth side warmth 104 of the time-series average temperature of the first side warmth 101 or less temperature difference more than 15 ℃, 70 ℃ and between the fourth side warmth 104 of the time-series average temperature and the seventh side temperature difference between the warm 107 may exceed less than 15 ℃ or 70 ℃, wherein a judgment of abnormality. On the contrary, the fourth side warmth 104 of the time-series average temperature and the seventh side warmth 107 between the less and the temperature difference over 15 ℃, 70 ℃, the fourth side warmth 104 of the time-series average temperature of the first side temperature difference between the warm 101 may exceed less than 15 ℃ or 70 ℃, wherein a judgment of abnormality.

[183]

The sixth evaluation method, both sides of the warmth of the ends (101, 107) and a side warmth (101, 107) of the opposite ends of the plurality of side warmth (101, 102, 103, 104, 105, 106, 107) immediately to next using the temperature difference between the warm side (102, 106) determines the bath surface flow conditions. That is, the first side warmth 101 and the first side warmth 101 up close to each in the second side is a temperature difference between the warm 102 over 15 ℃ of less than 70 ℃ located on one end, located on the other end seventh warm side 107 and the seventh time to satisfy the warm side 107 and a maximum in proximity to the sixth side warmth over both the temperature difference between the (106) 15 ℃, less than 70 ℃, it is determined as normal flow pattern.

[184]

Referring to Figure 15, the cast slab of the first section to both sides of the warm end of heat and for example, the first side, the first side was next to the second side than the temperature difference is more than, 70 ℃ 15 ℃ between warmth in the warmth. However, the difference in temperature between the first side and the second side heat and warmth in the second region exceeds 70 ℃, this bath surface flow detection unit 200 determines it as an abnormal flow condition. And through the flow control unit 400, first to fourth magnetic field generating unit (510a, 510b, 510c, 501d) of at least the control of any one of the operation, the first car-side heat and a second temperature between the side warm 15 ℃ or more, and is less than or equal to 70 ℃.

[185]

In this manner, according to the first embodiment of the present invention, a mold (10) providing a plurality of side warmth 100 on the upper side and detects the widthwise position by the temperature of the bath surface, and relative comparison with this, a flow state of the bath surface of the judges in real time. And presenting the evaluation methods or criteria for determining the bath surface into a plurality of flow state, and by using any one of them to determine the flow state of the bath surface in real time. Further, it is possible by controlling the operation of the magnetic field generating unit in accordance with the bath surface flow state is determined in real time, to control the bath surface with the floating state does not cause a low defect or defect rate. Therefore, even if the mold flux to the molten steel bath surface is applied in the slab casting, the bath surface flow control method using the invention embodiments bath surface flow control apparatus according to this, and for detecting a flow of the bath surface in real-time can be controlled. Thus, by reducing the bath surface defects caused by the flow, and improve the quality of the main room.

[186]

[187]

[188]

The above-described first embodiment, by using the difference of the temperature values ​​measured at a plurality of side warmth and determines whether the bath surface flow state is normal or abnormal conditions, and relative comparison with the temperature of the plurality of side warmth detecting the bath surface flow patterns It has been described that.

[189]

Meanwhile, the bath surface flow is variable for different reasons such as clogging of the nozzle, sliding whether air incorporation into the gate, the nose roll out of control of the inert gas supplied, the nozzle melting, also the type of flow pattern patterns be divided into a plurality of is. And it is effective to vary the control of the bath surface flow way depending on the type of the bath surface flow patterns.

[190]

Therefore, in the second embodiment of the present invention, the intra-mold molten steel in accordance with the flow pattern in the form of bath surface by the flow of the bath surface to adjust the control method, the bath surface flow that can reduce the cast defects generated in accordance with the bath surface flow control apparatus and using the same. bath surface provides a flow control method.

[191]

With reference to FIGS. 16 to 37, description will now be the bath surface flow control apparatus and the bath surface flow control method according to a second embodiment of the present invention. At this time, the information is redundant information as explained in the first embodiment is omitted or will be briefly described.

[192]

16 is a view illustrating a bath-surface flow control apparatus according to a second embodiment of the present invention. 17 and 18 is a diagram showing a mold with a plurality of side warmth and magnetic field generating unit is installed. 19 is a diagram showing the configuration of the screen Bullock bath surface flow control apparatus according to an embodiment of the invention. Figure 20 is a pair of long sides and a top with a plurality of side warmth provided on the short side respectively of the pair, Figure 21 is the transverse direction of in a pair of long sides and a pair of short sides, respectively measured by the plurality of side heat of the mold It will visualized the bath surface flow patterns where the relative-temperature indicated by the detection and graphed, Figure 22 is a visualization in three dimensions. Figure 23 is a top view showing a state installed on the long side and short-side side warmth provided each mold. 24 is a view illustrating a plurality of flow pattern types that are pre-stored or preset flow pattern in the type storage section in the embodiment; 25 is a view showing a double-roll type flow generated in the eighth flow pattern types shown in Fig. 26 is a view showing a single roll of the flow pattern in the seventh flow pattern types shown in Fig. 27 and 28 shows a first flow pattern type and a second flow pattern type of location-specific temperature distribution that is classified as a normal flow pattern in the embodiment of the present invention. 29 is a diagram illustrating a plurality of flow pattern types and thus the plurality of flow control according to the type that is pre-stored or preset the type of flow pattern storage section in the embodiment; 30 is a diagram showing the phases of two-phase alternating current applied to the magnetic field generating unit. Figure 31 to Figure 34 is a view for explaining the flow direction and the rotating flow of the molten steel in accordance with the two-phase alternating current applied to the magnetic field generating unit. 35 is a flow chart for explaining the bath surface flow control method according to an embodiment of the present invention. 36 is a flowchart illustrating a method of detecting bath surface flow patterns in the bath surface flow control method according to an embodiment of the present invention. 37 is a flowchart illustrating a method of classifying the bath surface flow detected at the bath surface flow control method according to an embodiment of the invention as a flow type.

[193]

16, the casting equipment including the bath surface flow control apparatus according to a second embodiment of the present invention, when supplied with molten steel from the nozzle 20, the mold on the mold 10, the mold 10 to cool the primary are spaced apart from the installation to be arranged in the transverse direction of 10, a plurality of side warmth 100 for measuring a temperature in each, is provided outside the mold 10 for forming a magnetic field for flowing of a molten steel in the mold 10 magnetic field generating unit 500), the mold 10 bath surface flow detection unit (200 to within the received detect the flow of the molten steel bath surface), the reservoir of the detected bath surface flow patterns or groups which one flow of the plurality of flow pattern type set flow pattern classification to classify the type of pattern unit 300, by controlling the bath surface flow by controlling the operation of the magnetic field generating unit 500) according to the classification flow pattern type, a molten steel bath surface is controlled to be in the form of a normal flow pattern U It includes such control unit 400.

[194]

That is, the second embodiment is the first embodiment and the bath surface flow control apparatus according to the side warmth 100, a bath-surface detecting unit 200, the flow control unit 400 and a configuration having a display unit 600 are similar, and the flow further comprising: a pattern classification unit 300, and controls the flow of the bath surface by selecting the control method in accordance with the classification flow pattern in the form of the flow control unit 400.

[195]

The second embodiment in the bath surface flow detection unit is relatively expressed by the width-direction position-specific temperature values ​​of the temperature measurement value to the mold 10 or the molten steel bath surface measured at each of a plurality of side warmth 100 in accordance with the position of the molten steel bath surface is converted into a relatively high specific detects a bath surface flow patterns.

[196]

More specifically, using the plurality of measured temperature value received from the plurality of side warmth 100 in the bath surface flow detection unit 200 than the process and method for detecting the bath surface flow patterns are as follows. A plurality of side warmth 100 is 16, 17 and a pair of longer sides (hereinafter, a first long side (11a), the second long side (11b)) of the mold 10 as shown in Figure 20 and a pair of of the short side (a first short side (12a) and a second short side (12b)) there is provided along the respective extension direction, the first and the second long side (11a, 11b) and first and second short sides (12a, 12b) described along each of the extending direction is a number from 1 to 10 number of the first and second long side (11a, 11b) and first and second short sides (12a, 12b) a plurality of warm side 100 is installed in each. In other words, the plurality is installed on the first and the second long side (11a, 11b) each of the mold 10 side warmth 100 for example to the right from the left side may be referred to as first to ninth side warmth, the mold first and second short sides (12a, 12b) a plurality of warm side 100 is installed on each can be referred to as a first side 10 warm. Embodiment, the plurality along the extension direction of the first and second short sides (12a, 12b), but a single side warm (i.e., the 10-side warmth) installed in each, but not limited to, a short side (12a, 12b) side there is a warm (100) can be installed.

[197]

The installed to the first embodiment as described in the example, the first and second long side (11a, 11b) of the plurality of side warmth 100 mold 10 and the first and second short sides (12a, 12b), for measuring the angular position-specific temperature, depending on the height of the bath surface, the temperature is measured are different. Accordingly, it is to detect the shape of the entire bath surface (or form) using the difference of the measured temperature at a plurality of side warmth 100. Thus, to indicate the temperature value measured at a plurality of side warmth 100, a width disposed arranged in the width direction of the direction or the bath surface of the mold 10 by location, so the temperature is dependent on the height of the bath surface, the relative said temperature value expressed as compared with, it can be seen the relative height of the bath surface. Accordingly, as expressed by relative comparison of the measured temperature values ​​from a plurality of warm side 100, it is possible to determine the position by the height of the bath surface with a relatively, it is possible to detect the bath surface flow patterns.

[198]

Then, when the screen for the first and second temperature in accordance with the position in each long side (11a, 11b) the direction of the mold 10 the graph, can be visualized as shown in Figure 21, this display portion 600, so that the operator can check on can be displayed (display). Also, by using the first and second and the temperature of the position at each long side (11a, 11b) direction, the first and the temperature of the location in each of two short sides (12a, 12b) the direction of the mold 10 , 22 a can be visualized in three dimensions (3D) as shown in, which can be displayed (display) on the display so that the operator can see.

[199]

Flow pattern classification unit 300 compares the detected bath surface flow patterns as previously set or previously stored flow pattern type, and the detected bath surface flow patterns comparison whether the flow pattern of any pattern type, and classification. The flow pattern classification unit 300 classifies the defect, or determines whether the likelihood of low flow pattern (hereinafter referred to as normal flow pattern) or, defects are likely to flow pattern (hereinafter referred to as abnormal flow pattern). The normal flow pattern is the bath surface flow patterns defective rate is not more than 0.8%, the abnormal flow pattern is the bath surface flow patterns which the defect rate exceeded 0.8%. This flow pattern classification unit 300 may cause the plurality of types of flow pattern types temperature ingestion by a plurality of flow pattern types of the flow pattern type storage unit 310, a detection bath surface flow patterns and the plurality of stored are stored in that during the molding operation flow compared to the pattern type, the bath surface of the detected flow pattern includes a plurality of flow patterns classified as one of the type, defined or determined pattern classifying unit 320 (see Fig. 19).

*****

Claims

[Claim 1]

A plurality of side warmth for measuring at a plurality of locations the widthwise temperature of the mold is accommodated in the molten steel therein; by the position measurement in the plurality of side warmth detects a bath surface flow patterns of the molten steel, the relative temperature values, the plurality of side by relative comparison with the temperature value measured in the warm, bath surface flow detection unit for determining a flow state of the molten steel bath surface in a normal or abnormal; is provided on the outside of the template, by generating a magnetic field, of the molten steel by the magnetic field magnetic field generating unit for controlling the flow; if the detected bath surface flow conditions in the bath surface flow detection unit is determined as normal, the holding operation of the magnetic field generating unit to its present state and the detected bath surface flow state is determined as an abnormal when the flow control unit for adjusting the bath surface flow by controlling the operation of the magnetic field generating unit so that the normal; bath containing If the flow control apparatus.

[Claim 2]

The method according to claim 1, wherein the bath surface flow detection unit is relatively expressed by the temperature measurement values ​​measured by the plurality of side warmth to the location-specific temperature value of the molten steel bath surface, bath surface flow control device for detecting a flow pattern of the molten steel bath surface.

[Claim 3]

The method according to claim 2, wherein the bath surface flow detection unit, comparing whether the calculated temperature difference between the respective temperatures of said plurality of side warmth, and said calculated plurality of temperature differences, each with the reference temperature range, the bath surface flow control apparatus for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 4]

The method according to claim 3, wherein the bath surface flow detection unit, and for each of the plurality of side warmth calculating the temperature difference between the other remaining side warmth, and compared with the reference temperature range, determines the bath surface flow state as normal or abnormal bath surface flow control apparatus.

[Claim 5]

The method according to claim 4, wherein the bath surface flow detection unit, and determines the bath surface flow of when both of the difference values ​​of the other remaining side warmth each temperature for each of the plurality of side warmth is incorporated into the reference temperature range to the normal state, bath surface flow control apparatus for determining the flow conditions outside the bath surface, at least one difference value is based on the temperature range of the difference value and each of the other remaining side temperature warmth for each of the plurality of side warmth as abnormal.

[Claim 6]

The method according to claim 2, wherein the bath surface flow detection unit, out of the plurality of side warmth, calculating the temperature difference between the side warmth in the both ends, and the calculated amount of end-side temperature difference each of the reference temperature range between warmth in the Compare whether contained in the bath surface flow control apparatus for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 7]

The method according to claim 2, wherein the bath surface flow detection unit, the plurality of side warmth of, installed in a temperature difference and the temperature and the other end on the side of warmth in the center between the side of warmth provided to the temperature and the one end of the side warmth in the heart side calculates the temperature difference between the warm and compares the temperature difference between the side of warmth provided to the temperature and the one end of the side warmth in the center of the reference temperature range, and side installed in the temperature and the other end on the side of warmth in the center warmth by comparing the temperature difference between the reference temperature range, the bath surface flow control apparatus for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 8]

The method according to claim 7, wherein the bath surface detection unit, a temperature difference and a difference in both the reference temperature range temperature between side warmth provided on the heat and the other end located in the center between the side warmth and side warmth provided on one end located in the center when included in the temperature difference between the determination the flow state of the bath surface with the top and side installed in the temperature difference and the side heat and the other end located in the center between the side warmth and side warmth provided on one end located in the center of warmth, at least one bath surface flow control apparatus for determining a flow state of the bath surface as an abnormal time is out of the reference temperature range.

[Claim 9]

The method according to claim 2, wherein the bath surface flow detection unit, calculates the average temperature on the side of warm temperatures of the plurality, and the plurality of side warmth, differential, and other end between the temperature and the average temperature on the side of warmth in the one end the side and the temperature of the heat and calculating a difference between the average temperature is located in, by comparing the temperature difference between the one side and the temperature and the average temperature on the side of warmth in the other end with the reference temperature range, the flow state of the molten steel bath surface bath surface flow control device to determine a normal or abnormal.

[Claim 10]

The method according to claim 9, wherein the bath surface flow detection unit, bath surface flow when said average temperature and said one side warmth temperature between in the end cars and the average temperature and the temperature between side warmth located at the other end of the car all included in the standard temperature range, a flow state of the bath surface when determining the state to normal, wherein at least one of the temperature difference between the average temperature and the one end side warmth temperature between in the car and the average temperature and the side of warmth in the other end is outside the reference temperature range bath surface flow control apparatus for judging as abnormal.

[Claim 11]

The method according to claim 2, wherein the bath surface flow detection unit, while the cast casting, real time the temperature of the side of warmth in the side warmth, one side and the other end located in one of a plurality of side warmth installed so listed, along the width direction of the mold, the center measured, and calculates the time-series average temperature on the side of warmth in the center, and calculating the output of time-series average temperature and one side and the temperature on the side of warmth in the other end tea, respectively, and the calculated time-series average temperature and by comparing the temperature difference between the warm side and the other side located at one side end and the reference temperature range, the bath surface flow control apparatus for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 12]

The method according to claim 11, wherein the bath surface flow detection unit, and from the casting initially to discharge the molten steel in the mold measure the temperature on the side of warmth in the center, and calculating the thermal average temperature watch in real time, the side located in the center of warmth clock after the calculated average to a constant thermal temperature time, the bath surface flow control device using a warm side temperature of each is located on the one side and the other end to judge the condition of the molten steel bath surface flow.

[Claim 13]

The method according to claim 12, wherein the bath surface flow detection unit, a time series average temperature on the side of warmth in the temperature difference and the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end and the other end on the temperature difference and the center between the side warm temperature difference between both is determined as the normal flow conditions of the bath surface when incorporated into the reference temperature range, side time series average temperature on the side of warmth in the center and located on the one end of warmth between the in located side heat of clock bath surface flow control apparatus for determining a flow state of the bath surface of the abnormality when the temperature difference between the warm side in thermal average temperature and the other end, at least one out of the reference temperature range.

[Claim 14]

The method according to claim 2, wherein the bath surface flow detection unit, in the cast molding, the plurality of side warmth installed so listed, along the width direction of the mold, and the side warmth in the one end, the side is installed right next to the one end warmth , and the side warmth in the other end, to measure the next side temperature of warmth provided to the other end, and the temperature on the side of warmth in the one end, the temperature between the temperature at the side of warmth provided to the right side of said one end the difference value of the first, and calculates the temperature difference, the temperature of the side of warmth in the other end, to yield a first temperature difference between the temperature at the side of warmth provided to the right by the second temperature difference between the other end, the first temperature difference and the second temperature to the primary, respectively compared with the reference temperature range, the bath surface flow control apparatus for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 15]

The bath surface flow detection unit according to claim 14, of the first temperature differential and a second temperature difference when all of it is included in a reference temperature range, determining the bath surface flow state to normal, and the first temperature differential and a second temperature difference when the at least one out of the reference temperature range, the bath surface flow control apparatus for determining the bath surface flow state as abnormal.

[Claim 16]

A method according to any one of claim 3 to claim 15, wherein the flow control unit, the calculated temperature difference to determine the location of the side warmth out of the reference temperature range, side the calculated temperature difference is outside the reference temperature range warmth and the bath surface corresponding to position the flow control device to control the operation of the magnetic field generating unit, to control at least one of a moving direction, moving speed and strength of the magnetic field.

[Claim 17]

The method according to claim 16, wherein the flow control unit, wherein the detecting a difference between the calculated temperature difference and the reference temperature range, and the calculated temperature difference, and determines whether less than or greater than the reference temperature range, the calculated temperature difference and the reference temperature in accordance with the difference between the range and adjusting the amount of current applied to the magnetic field generating unit, the calculated temperature difference is based on whether less than or greater than the reference temperature range, the molten steel from the nozzle provided in the mold the discharge direction in the same or opposite direction bath surface flow control apparatus to move the magnetic field in the magnetic field generating unit.

[Claim 18]

The method according to claim 2, analyzes the detection bath surface flow patterns in said flow detection unit, group includes a plurality of flow pattern types of any of the flow pattern classification unit for classifying the flow pattern type of the saved, the flow control unit is the and a plurality of flow control type according to a plurality of flow pattern types stored in the flow pattern classification unit is stored, to select one of the flow control type according to the flow pattern type of the classification of the plurality of the flow control type, the magnetic field generated bath surface flow control device for controlling the drive of the unit.

[Claim 19]

The method according to claim 18, wherein the flow pattern classification unit, the flow pattern-type storage unit of the plurality of flow pattern types stored; a plurality of flow pattern types stored in the group and the temperature data of the detected bath surface flow patterns in the bath surface flow detection unit, to the data of the temperature contrast pattern classifying unit for classifying the flow pattern into any one type of the detected bath surface flow patterns of flow pattern types of the plurality of groups stored; bath surface flow control apparatus comprising a.

[Claim 20]

The method according to claim 19, wherein the flow pattern a plurality of flow pattern types stored in the type storing portion is classified into different types of flow pattern types, depending on the temperature distribution in the bath-surface location by the temperature and the bath surface of the plurality of the flow pattern type bath surface flow control apparatus comprising a defect that have a lower likelihood of at least one normal flow pattern, a defect caused by the potential of the bath surface flow is high plurality unsteady flow pattern by the bath surface flow.

[Claim 21]

The method according to claim 20, wherein the flow control unit, the flow pattern in accordance with a plurality of flow pattern types stored in the type storing portion changes the control condition of the magnetic field generating unit, storing a plurality of flow control type to control the bath surface flow in accordance with the classification flow pattern type, of a plurality of the flow control type, one of the flow control type selection unit for selecting the flow control type is stored in the flow-control-type storage unit;; flow control type storage unit the flow control type selection bath surface flow control apparatus comprising a; depending on the type of flow control is selected in the sub-electromagnetic field control part for controlling the power supplied to the magnetic field generating unit, and controlling the movement direction of the magnetic field.

[Claim 22]

The method according to claim 21, wherein the mold facing each other provided with a first and a second long side, a first long side and the second located between the long side and includes a first and a second short side is installed's spaced apart from each other are facing, the plurality on the side of warmth is installed in each of the first and second long sides and the first and second short sides of the mold, the first and the center position of the second long side direction of the mold a nozzle for discharging the molten steel into the mold is provided the magnetic field generating unit is installed to be arranged in the first and second magnetic field generation section is provided so as listed in the extending direction of the first long side, are installed so that the symmetry with respect to the nozzle, the extension direction of the second long side, Article comprising the third and fourth magnetic field generating section, the electromagnetic field controller is installed so that the symmetry with respect to the nozzles of the first to fourth is connected to the magnetic field generating unit, said flow control type selector Stand according to the selected flow control type bath surface flow control device for controlling the first to fourth controls the power applied to the magnetic field generating unit, respectively, the first to fourth magnetic field moving in the magnetic field generating section each direction.

[Claim 23]

The method according to claim 22, wherein the flow control unit is said detected when the bath surface flow patterns classified in the normal flow pattern, and held in the first to fourth magnetic field generating portion magnetic field movement direction, said detection bath surface flow patterns with a plurality of when classified by any one of an abnormal flow pattern, bath surface flow control device for controlling the first to fourth magnetic field generator, each magnetic field of the moving direction of the bath surface of the detected flow pattern so that the normal flow patterns.

[Claim 24]

The method according to claim 23, wherein the flow control unit includes first to fourth magnetic field generator each of the magnetic field movement direction, the first to fourth magnetic field along the magnetic field movement direction and the current density in the selected flow control type has bath surface flow control device for controlling the current density applied to the generator, respectively.

[Claim 25]

A method according to any one of claim 3 to claim 15 and claim 18 to claim 24, wherein the plurality of side warmth bath surface flow control apparatus which is installed spaced apart at equal intervals in a position higher than the molten steel bath surface is accommodated in the mold.

[Claim 26]

The method according to claim 25, wherein the warm side of the bath surface flow control apparatus which is installed at a height of less than 50mm from the bath surface.

[Claim 27]

A method according to any one of claim 3 to claim 15 and claim 18 to claim 24, the separation distance between the side warmth disposed in a fixed-width region of the template of the plurality of side warmth, which is located outside of the fixed-width region large bath surface than the spacing between the side of the warmth is arranged to fluctuation area flow control apparatus.

[Claim 28]

The method according to claim 27, wherein the plurality of side warmth bath surface flow control apparatus which is installed at a height of less than 50mm in the top and bottom from the bath surface of the molten steel.

[Claim 29]

The method according to claim 27, wherein the mold long sides and a pair of opposite spaced apart from each other, and a pair of short side is provided so as to face each other on either side of the long side, the plurality of side warmth bath surface flow that is provided on the long side controller.

[Claim 30]

The method according to claim 27, the separation distance 55 to the bath surface 300㎜ flow control device between the warm side being arranged on the fixed-width region.

[Claim 31]

The method according to claim 27, the separation distance 10 to the bath surface 50㎜ flow control device between the warm side being arranged on the variation region.

[Claim 32]

The method according to claim 28, which is toward the outer bath surface from the center of the long side of the width direction reduces the distance between the warm side of the plurality flow control apparatus.

[Claim 33]

The method according to claim 29, the bath surface flow control apparatus which is gradually reduced toward the outside of the spacing distance between the warm side being arranged on the fixed-width region.

[Claim 34]

The method according to claim 29, the bath surface flow control apparatus which is gradually reduced toward the outside of the spacing distance between the warm side being arranged on the variation region.

[Claim 35]

Using a plurality of side warmth installed so listed, along the width direction of the mold, comprising the steps of: measuring the temperature at a plurality of positions of the molten steel bath surface in the width direction; and relative analysis to the temperature according to each of the measured position of said molten steel detected by the bath surface flow patterns, and by comparing the temperature values ​​measured by the plurality of relatively warm side, the steps of: determining a flow state of the molten steel bath surface in a normal or abnormal; And the operation of the magnetic field generating unit when the maintenance operations of the magnetic field generating unit installed in the outside of the mold to its present state and the flow state of the bath surface that is determined as abnormal if the flow state of the bath surface that is determined as normal by adjusting the controls, the magnetic field, the process of the bath surface is adjusted such that the normal flow; bath surface flow control method comprising a.

[Claim 36]

The method according to claim 35, analyzes the temperature according to each of the measured relative position, relative to the process of detecting a bath surface flow patterns of the molten steel is relatively compared with a plurality of temperature measurements, for each position of the molten steel bath surface by expressing the height, bath surface flow control method comprising the step of detecting a bath surface of the molten steel flow pattern.

[Claim 37]

The method according to claim 35, the method for determining a flow state of the molten steel bath surface in a normal or abnormal, the calculated temperature difference between the temperature of the plurality of side warmth, respectively, and wherein the calculating the plurality of temperature difference each of the reference temperature range Compare whether include, bath surface flow control method for determining a flow state of the molten steel bath surface in a normal or abnormal.

[Claim 38]

The method according to claim 37, calculating the temperature difference between the temperature of the plurality of side warmth, respectively, and the process in which the plurality of calculated temperature difference each comparison whether included in the reference temperature range, each of the plurality of side warmth calculating a temperature difference between the other remaining side warmth for, bath surface flow control method comprising the step of comparing with the reference temperature range.

[Claim 39]

The method according to claim 38, both of the difference values ​​of the other remaining side warmth each temperature for each of the plurality of side warmth determines the bath surface flow when incorporated into the reference temperature range to the normal state, each of the plurality of side warmth of the difference values ​​for the other remaining side warmth each temperature, the bath surface flow control method for determining at least one difference value is outside the reference temperature range bath surface flow state as abnormal.

[Claim 40]

The method according to claim 35, the step of determining a flow state of the molten steel bath surface in a normal or abnormal, the process of one of the plurality of side warmth, by using the side warmth provided on both ends measure the temperature in real time; located on the opposite ends a; side by calculating the temperature difference between the warm and compares whether the temperature difference respectively between side warmth located on the calculated both ends contains a reference temperature range, the process of determining a flow state of the molten steel bath surface in a normal or abnormal bath surface flow control method comprising.

[Claim 41]

The method according to claim 35, the step of determining a flow state of the molten steel bath surface in a normal or abnormal is, of the plurality of side warmth, by using the side warmth provided on the warmth in the heart, the side provided on one end of warmth and the other end the step of measuring the temperature in real time; calculating a temperature difference between the side of warmth provided to the temperature difference and the temperature and the other end on the side of warmth in the center between the side of warmth provided to the temperature and the one end of the side warmth in the center ; and temperature and compares the temperature difference between the side of warmth provided on one end and a reference temperature range, and based on the temperature difference between the side of warmth provided to the temperature and the other end on the side of warmth in the center of the temperature range at the side of warmth in the center comparison, the process of determining a flow state of the molten steel bath surface in a normal or abnormal; bath surface flow control method comprising a.

[Claim 42]

The method according to claim 41, a flow state of the bath surface, when the center-side heat and the temperature difference between the side of warmth provided on one end and a temperature between side warmth provided on the heat and the other end located in the center in the car all included in the standard temperature range, it is determined as normal, bath surface when one or more of the temperature difference between the side warmth and side warmth provided to the other end located on the temperature difference and the center between the side warmth and side warmth provided on one end located in the center, at least one is outside the reference temperature range bath surface flow control method for determining a flow state as abnormal.

[Claim 43]

The method according to claim 35, the step of determining a flow state of the molten steel bath surface in a normal or abnormal is the step of using said plurality of side warmth measuring the temperature in real time; calculating an average temperature for the side warm temperatures of the plurality process; calculating a difference between the plurality of side warmth of the temperature of the side warm position to the difference and the other end between the temperature and the average temperature on the side of warmth in the one end and said average temperature; on the one side and the other end compared to the temperature difference between the in-side temperature and the average temperature of the heat and the reference temperature range, the process of determining a flow state of the molten steel bath surface in a normal or abnormal; bath surface flow control method comprising a.

[Claim 44]

The method according to claim 42, and determining the flow conditions of the bath surface to normal when said average temperature and said one side warmth temperature between in the end cars and the average temperature and the temperature between side warmth located at the other end of the car all included in the standard temperature range, bath surface flow control for determining a flow state of the bath surface when said average temperature and said one side warmth temperature between in the end car and at least one of the temperature difference between the average temperature and the side of warmth in the other end is outside the reference temperature range by abnormal Way.

[Claim 45]

The method according to claim 35, the step of determining a flow state of the molten steel bath surface in a normal or abnormal, the process of one of the plurality of side warmth, measuring the side warmth, side temperature of the warm located on one side and the other end is located in the center in real time, ; calculating a time series average temperature on the side of warmth in the center; the calculated clock calculating a temperature difference between the side warmth in the thermal average temperature and one and the other ends, respectively; the calculated time-series average temperature and compared to the temperature difference between the warm side and the other side located at one side end and the reference temperature range, the process of determining a flow state of the molten steel bath surface in a normal or abnormal; bath surface flow control method comprising a.

[Claim 46]

The method according to claim 45, according to calculate the side time series average temperature of the warm located in the center, calculated from the casting initially to discharge the molten steel in the mold measure the temperature on the side of warmth in the center in real time, the thermal average temperature clock and, after the calculation to a certain side of the warm time series average temperature in the central point, the bath surface flow control method for using the warm side temperature of each is located on the one side and the other side end of the bath surface determines the flow state of molten steel.

[Claim 47]

The method according to claim 46, the difference time series on the side of warmth in the center of the average temperature and the one end-side heat of the temperature difference and the side warmth in the central clock between in the Thermal average temperature and the temperature between side warmth in the other end all of determining a flow state of the bath surface by top, and the side in the temperature difference and the center between the time-series average temperature on the side of warmth in the center and side warmth in the one end of warmth when incorporated into the reference temperature range time-series average temperature bath surface and the flow control method of the temperature difference between the warm side, located on the other end, at least one is determined as an abnormal state of the bath surface when the flow goes out of the reference temperature range.

[Claim 48]

The method according to claim 35, the step of determining a flow state of the molten steel bath surface in a normal or abnormal, on the one of the plurality of side warmth, side warmth in the one end, side warmth is installed right next to the one end, the other end located side warmth and a process of measuring the temperature of the side is installed right next to the other end of warmth; and the temperature at the side of warmth in the one end, just the temperature difference between the side temperature of warmth provided to the next value of said one end of a first step of calculating a temperature difference; the process of calculating the temperature on the side of warmth in the other end, and the right temperature between the temperature at the side of warmth provided to the next difference value between the other end a second temperature difference; the first temperature difference and the second temperature compares each difference with a reference temperature range, the process of determining a flow state of the molten steel bath surface in a normal or abnormal; bath surface flow control method comprising a.

[Claim 49]

The method according to claim 48, wherein the first temperature differential and a second temperature difference when all of it is included in a reference temperature range, determining the bath surface flow state to normal, and the first temperature differential and the second temperature difference is at least one reference temperature range of when out of the, bath surface flow control method for determining the bath surface flow state as abnormal.

[Claim 50]

A method according to any one of claim 37 to claim 49, wherein the reference temperature is the temperature difference value, the flow control method bath surface the cast defect rate being less than 80%.

[Claim 51]

The method according to claim 50, wherein the reference temperature is more than 15 ℃, 70 ℃ or less bath surface flow control method.

[Claim 52]

A method according to any one of claim 37 to claim 49, the process in which the bath surface flow adjusted such that the normal, the process of the calculated temperature difference determine the location of the side warmth out of the reference temperature range; difference in the calculated temperature of the to control the operation of the magnetic field generating unit corresponding to the position outside the side of the reference temperature range, warm the step of adjusting at least one of a moving direction, moving speed and strength of the magnetic field; bath surface flow control method comprising a.

[Claim 53]

The method according to claim 52, wherein the calculated temperature difference between the process for controlling the operation of the magnetic field generating unit corresponding to the location and warm side is outside the reference temperature range, detecting a difference between the calculated temperature difference and the reference temperature range, the the process of the calculated temperature difference determines whether less than or greater than the reference temperature range; the process of adjusting the amount of current applied to the magnetic field generating unit according to the difference between the calculated temperature difference and the reference temperature range; the calculation method bath surface flow control including; a temperature difference between the process of, depending on whether less than or greater than the reference temperature range, to move the magnetic field in the magnetic field generating unit in the molten steel discharge direction the same or opposite direction from the nozzle provided in the mold .

[Claim 54]

The method according to claim 36, the process of classifying the one flow pattern types of the above-described stored on the detected bath surface flow patterns plurality flow pattern type; selecting any one of the classified flow pattern type plurality of flow control type previously stored in accordance with the the process of selecting a flow control type; bath surface flow control method including the; process for controlling a magnetic field formed in the magnetic field generating unit installed in the outside of the mold to the selected flow control type.

[Claim 55]

The method according to claim 54, the process of classifying the one flow pattern type of the of the of the detected bath surface flow patterns pre-stored plurality of flow pattern types, and storing classified a plurality of flow pattern types that can occur in the casting process ; process classified as of the detected bath surface flow forms a plurality of flow pattern types of the previously stored temperature data from, any of the flow pattern type; the process to prepare the bath surface flow pattern is detected and the group plurality of flow pattern types stored bath surface flow control methods, including;

[Claim 56]

The method according to claim 55, wherein the group a plurality of flow pattern type, the stored bath surface containing the defect that have a lower likelihood of at least one normal flow pattern, with a high defect potential generated by the bath surface flow plurality unsteady flow pattern by the bath surface flow how the flow control.

[Claim 57]

The method according to claim 56, in controlling the magnetic field formed in the magnetic field generating unit in the above classification flow pattern type of the plurality of the flow control type, select the flow control type respectively corresponding to each of the plurality of flow pattern types, wherein applying power to the magnetic field generating unit as selected by the flow control type, bath surface flow control method for controlling the magnetic field direction of movement of the magnetic field generating unit.

[Claim 58]

The method according to claim 57, in controlling the magnetic field formed in the magnetic field generating unit to the classification flow pattern type, according to the magnetic field movement direction and the current density in the selected flow control type having, a magnetic field moving in the magnetic field generating unit direction bath surface and the flow control method to control the current density.

[Claim 59]

The method according to claim 58, wherein the mold facing each other provided with a first and a second long side, a first long side and the second located between the long side and includes a first and a second short side is installed's spaced apart from each other are facing, the plurality on the side of warmth is installed in each of the first and second long sides and the first and second short sides of the mold, the first and the center position of the second long side direction of the mold a nozzle for discharging the molten steel into the mold is provided the magnetic field generating unit is installed to be arranged in the first and second magnetic field generation section is provided so as listed in the extending direction of the first long side, are installed so that the symmetry with respect to the nozzle, the extension direction of the second long side, and comprising a generator 3 and a fourth magnetic field are installed so that symmetrical with respect to the nozzle, to control the operation of the magnetic field generating unit, by controlling the magnetic field, wherein the bath surface flow so that the normal According to control, flow control for controlling the first to fourth controls the power applied to the magnetic field generating unit, respectively, the first to fourth magnetic field moving in the magnetic field generating section each direction according to the selected flow control type Way

[Claim 60]

The method according to claim 59, in the detected bath surface flow patterns, of a plurality of temperature measurements of the detection at a plurality of positions on one side and the other side respectively of the bath surface of the nozzle, with respect to temperature variation, bath surface center temperature between the lowest temperature and the highest temperature high and the temperature of the both edges of the bath surface low, the amount by the difference between the edge temperature and the bath-surface center temperature of the normal flow pattern, and are classified as an abnormal flow pattern, the plurality of flow pattern types, each temperature of the plurality of the flow pattern from the data, higher of the lowest temperature and the temperature of the both edges of the bath surface of the temperature range, bath surface center temperature between the highest temperature low, bath surface flow that is classified by the difference between the positive edge of the temperature and bath surface center temperature in different abnormal flow pattern type A control method.

[Claim 61]

The method according to claim 60, wherein in the detection bath surface temperature value of the flow patterns, large and equal to or greater than the minimum temperature and the bath-surface temperature difference is based the temperature of each of the center temperature of satisfying the standard deviation, and the bath-surface both edges is set difference between the maximum temperature the when bath surface both edges meet each temperature and the central difference in the first and second temperature deviations each of the reference value or less among the temperature, the classification to the normal flow pattern, and the bath-surface temperature difference is out of the standard deviation, or the first and a second temperature range, respectively when the center temperature is less than or greater than the first and second temperature range, at least one reference value which is predetermined from, bath surface flow control method of classifying an abnormal flow pattern.

[Claim 62]

The method according to claim 61, wherein when the detection bath surface flow patterns are classified by any one of a plurality of abnormal flow pattern type, at least one of a temperature of the both edges of the detected bath surface flow pattern is greater than the core temperature, the first to the fourth bath surface, which in the sub-field generation, by controlling the magnetic field in the portion of the both side area of ​​the nozzle, the temperature of the edge in response to a large area compared with the central temperature magnetic field generated so as to move to the nozzle direction, decelerating the molten steel flow velocity how the flow control.

[Claim 63]

The method according to claim 62, when if the detected bath surface flow patterns are classified by any one of a plurality of abnormal flow pattern, at least one of a temperature of the both edges of the detected bath surface flow pattern is less than the core temperature, the first to the fourth in the sub-field generation, by controlling the temperature of the edges to move in the outward direction from the magnetic field at the corresponding in part the magnetic field generated in a small area nozzle relative to a center temperature, bath surface flow control method for accelerating the flow velocity of the molten steel.

[Claim 64]

The method according to claim 61, wherein the amount of the difference in temperature between the temperature and the central temperature of the edge of the larger first to fourth by increasing the current density to be applied to at least any one of a magnetic field generating unit, bath surface flow to increase the acceleration or deceleration force of the molten steel A control method.

[Claim 65]

The method according to claim 61, wherein when the detection bath surface flow patterns are classified by any one of a plurality of abnormal flow pattern of the detected bath surface flow patterns is a difference between the both edges of each of the temperature and the central temperature value of the reference deviation Choi If less than the lower limit, the first to fourth by the different magnetic field in the direction of movement of the magnetic field generating unit, respectively, the flow control method bath surface to rotate the molten steel.