KR20040055855A - A Method for Setting the Work Condition of Annealing Furnace using Material Characteristic of Strip - Google Patents

Abstract

PURPOSE: A method for setting working conditions of the annealing furnace process is provided to improve quality of the strip by automatically setting factors for influencing the material properties of the strip using material properties of strip feedbacked from the annealing furnace process. CONSTITUTION: The method comprises a correlation calculating step (S41,S42) of setting working conditions of the annealing furnace process having an effect on material properties of strip per types and sizes of the strip, and calculating a correlation between the material properties of the strip and the working conditions of the annealing furnace process; a material property detecting step (S43,S44) of detecting material properties of an annealing operation completed strip; a material property comparing step (S45) of comparing the material property detected value of the strip with a preset material property target value of the strip; and a working condition setting step (S46,S47) of maintaining presently set working conditions if the two values correspond to each other after the comparison results, and resetting working conditions of the annealing furnace process according to the material property detected value of the strip using the calculated correlation if the two values do not correspond to each other, wherein the working conditions are line speed, skin pass mill elongation and annealing furnace heating temperature, and wherein the material properties of the strip are yield strength, tensile strength and elongation.

Description

A Method for Setting the Work Condition of Annealing Furnace using Material Characteristic of Strip}

The present invention relates to an annealing furnace process of steel sheet material, and more particularly, by using the steel sheet material properties (yield strength, printing strength and elongation) fed back from the annealing furnace process, the line speed and temper which are influence factors of the steel sheet material characteristics. The present invention relates to a method for setting an annealing furnace process working condition using material characteristics of a steel sheet which improves the steel sheet quality by automatically setting the rolling elongation and annealing furnace temperature.

When iron is subjected to external force at room temperature, it causes a change of grains and forms plastic deformation. In this process, internal stress increases and hardness increases sharply. As a result, elongation is lowered and flexibility as steel is inferior. Even in the cold rolling process of hot rolled coils, strips have a high residual stress (storage energy or internal stress) during the rolling process, so the hardness is very high and the ductility is poor. Difficulties follow Therefore, this problem is only required to heat the cold rolled STRIP to a suitable temperature, this heat treatment is referred to as "soft annealing". In other words, soft-annealing the cold-rolled strip removes the internal stress of the steel sheet, so that the material has a ductility suitable for processing.

1 is a schematic diagram of a general annealing furnace process. As illustrated in FIG. 1, the strip movement before and after the annealing furnace process will be briefly described. After the cold rolling process 11, the coiled strip 12 is welded with different steel 12 and contaminants. This is removed 13. Then, before entering the annealing furnace 15, the ELT 14 is required to secure the welding time. The strip passing through the annealing furnace 15 requires a DLT (16) to secure the winding time of the tension reel 19, and removes the CO (17), which may occur later, and cuts the weld again ( 18). Subsequently, the strip is wound on the tension reel 19 for each product.

Subsequently, although not shown in the drawings, the function and material change of the steel sheet in each section of the annealing furnace depending on the speed in the annealing furnace 15 are as follows.

In the preheating furnace (WGR: Waste Gas Pre-heating), there is no change in the material of strip and preheat the steel plate temperature to 200 ~ 280 ℃ by using the waste gas generated in the annealing furnace. It is a sex energy facility to reduce. Heating in a radiant tube section (RTS) is a method of installing a burner inside a radiant tube to heat the inside of the tube and indirectly heating the steel sheet by radiant heat. It also prevents the occurrence of oxygen and blocks the mixing of oxygen in the atmosphere gas. The indirect heating furnace plays the most important role in terms of securing the material of the plate. Of course, even in an indirect heating furnace has a function to remove the surface oxide film due to the hydrogen reducing power of the atmosphere gas, but rather the purpose is to secure the heat treatment temperature according to the steel grade. The interior of the RTS is largely divided into two compartments. Crystallization of the steel sheet is made during the heating section, and grain growth occurs during the soaking section, and most of the annealing treatment is made in the RTS. It can be said. For reference, the lower the carbon content, the higher the annealing temperature, and the higher the cracking temperature below the A3 transformation point, the higher the grain growth and the higher the workability (elongation, elongation, tensile strength (TS) and yield strength (YP) Decrease), if the cracking temperature is higher than A3 point or stays in the furnace for a long time, coarsening of grains will weaken the material.

During the heating and cracking in the indirect heating, the steel sheet material has completed the recrystallization and grain growth, but if cooled as it is, it becomes an unstable structure that may cause aging deformation in the future due to the aging change of the dissolved carbon in the component. Slow cooling treatment to reduce and reduce the amount of carbon prevents aging change. In the Rapid Cooling Section (RCS), the steel sheet heated to about 760 ° C in the indirect furnace is rapidly cooled down to about 550 ° C, miniaturizing the coarse grains and causing an increase and solid saturation of solid solution carbon. It gives the precipitation driving force of carbon.

When C, N, etc. are dissolved in the grains of the steel sheet, aging occurs when the supersaturated dissolved carbon moves to lattice defects such as dislocations over time, causing stiffness to decrease and hardness and strength to increase. It causes material defects such as mechanical deterioration and deformation. Therefore, in the slow cooling section (SCS), the impurities (mainly solid carbon) in the grains are diffused and precipitated to the nucleation site (Site) to equilibrate the amount of solid carbon in the tissue, thereby preventing aging change. There is a purpose. In terms of plating adhesion, low pressure management to prevent temperature drop, rising DEW POINT, and prevention of oxide film generation due to oxygen invasion are followed.

The material securing of the strip is almost done during the indirect furnace through the slow cooling zone, and the final cooling section (FCS) has the function of ensuring the temperature suitable for plating. In terms of plating adhesion, the most desirable alloy layer can be formed when the temperature of the steel sheet into which the plating bath (POT) is drawn and the temperature of the plating bath coincide with each other. When it becomes low and it becomes too high, peeling will arise because the Fe-Zn alloy layer becomes too thick. Therefore, the temperature of the final cooling zone is set in consideration of the temperature drop caused by the roll contact, the atmosphere gas, etc., in the process of drawing into the plating bath from the final cooling zone temperature measurement position according to the thickness of the steel sheet. In general, it is recommended to set a slightly higher material for the prevention of over-plating and mini-spangle formation and also plays an important role in maintaining the plating bath temperature.

In addition to general low carbon steel, Ti-Nb-added ultra-low carbon steel, P-added high tensile strength steel, etc., there are various kinds of steel according to the demanded use. However, unlike general low carbon steel or structural steel, in case of ultra low carbon steel and high tensile steel, which require deep workability, securing and demanding products with target material characteristics are required. Strict management of annealing temperature between coils and coils is required for quality assurance. In particular, it is necessary to manage material deviations in products by minimizing temperature deviations.

In the annealing process, the change of mechanical properties according to the annealing temperature shows different behaviors by steel type, but the yield strength is about 1.0 to 5.7 kg / mm ² and the tensile strength is about 0.5 to 3.8 kg / mm <^2> and elongation show the change of 1.6-8.9%.

Strip temperature control is based on the criteria registered in the manufacturer's design database. Since the steel sheet temperature by material and thickness are displayed on the computer screen, heat treatment is performed according to the above indication standard. Indirect heating cracking zone steel plate temperature of the hot dip plating process is specified in the work order of the host computer.

However, as shown in FIG. 2, which shows a control conceptual diagram of a conventional annealing process, the conventional control system 22 does not feed back the current state of the material, but only the process temperature conditions according to the steel grade and steel sheet size from the host computer 21. Worked. In the existing control system that performs annealing only by the temperature indication, there is a problem that material defects occur at the front and the end of the product coil because automatic feedback is not possible by measuring the material properties online.

The present invention has been proposed to solve the problem of material defects in the product by setting the process temperature without considering the online material properties in the existing system as described above. Steel plate material that improves the product's material quality by setting the line speed, temper rolling elongation and annealing furnace temperature, which are the influence factors of the material, by feeding back the material characteristics in the actual site without taking the way of working accordingly. The purpose of the present invention is to provide a method for setting working conditions in an annealing furnace process using material properties.

1 is a schematic diagram of a general annealing furnace process.

2 is a configuration diagram of a control system of a conventional annealing process.

3 is a block diagram of a control system of the annealing process according to the present invention.

4 is a flowchart showing a process of setting an annealing furnace process working conditions using steel sheet material properties in the annealing process according to the present invention.

Explanation of symbols on the main parts of the drawings

15: Annealing Furnace 31: Top Computer

32: online material measuring machine 33: working condition setting part

34: comparison unit 35: working condition adjustment unit

The present invention for achieving the above object is to set the operating conditions of the annealing furnace process affecting the material properties of the steel sheet by the type and size of the steel sheet, and the correlation between the material characteristics of the steel sheet and the operating conditions of the annealing furnace process A correlation calculation step of calculating a relationship; A material property detection step of detecting material properties of the steel sheet after the annealing operation is completed; A material property comparison step of comparing a material property detection value of the work steel sheet with a material property target value of a predetermined steel sheet; And if the two values coincide with each other as a result of the comparison, if the two values match, the operating conditions of the annealing furnace process according to the material characteristic detection value of the steel sheet are reset using the calculated correlation. The setting step is included.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail the present invention.

3 is a configuration diagram of a control system of an annealing process for performing a process working condition setting process according to the present invention. As shown in FIG. 3, the annealing process control system for setting the annealing furnace process working conditions according to the present invention passes through an upper computer 31 and an annealing furnace 15 for setting the type and size of the steel sheet to be worked. On-line material measuring device 32 which measures the material of the strip and transmits the result of material measurement online, and receives the data about the type and size of the steel sheet to be worked from the upper computer 31, and works the annealing furnace process according to the steel sheet Work condition setting unit 33 for setting a condition, a comparison unit 34 for comparing the material property measurement value transmitted from the on-line material measuring device 32 with a predetermined material property target value and transmitting the comparison result, and the two When a difference in value occurs, the work condition adjusting unit 35 calculates and outputs a new work condition using the material property measurement value fed back from the online material measuring machine 32.

Here, the online material measuring device 32 uses "IMPOC" developed by the German EMG company.

In the present invention, the line speed, the tempered rolling elongation (SPM EL), which are factors influencing the steel material (yield temperature (YP), tensile strength (TS), and elongation (EL)), in order to automatically adjust the material of the steel sheet. And how the annealing furnace heating temperature (HS) is correlated with each other by using the performance data. The following describes the regression formula for each material according to each steel grade (deep processing steel, low carbon steel, high tensile strength steel).

(1) deep processing steel

end. Yield Strength (YP)

YP = 150 + 0.213 Speed + 31.1 SPM EL-0.0580 HS ........ (Equation 1)

division Coefficient SE error T P value VIF a constant 150.06 17.63 8.51 0.000 Speed 0.21335 0.01960 10.89 0.000 1.3 SPM EL 31.078 1.665 18.66 0.000 1.6 HS -0.05803 0.01993 -2.91 0.000 1.3

S = 0.9455 R-Sq = 98.4% R-Sq (adj) = 98.1%

Where R-Sq (adj) is the coefficient of determination

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 949.99 316.36 353.89 0.000 Residual Error 17 15.20 0.89 Total 20 964.29

(Where: DF: degrees of freedom, SS: sum of squares, MS: sum of squares, F: F distribution, and P: level of significance)

I. Tensile Strength (TS)

TS = 538 + 0.281 Speed-7.61 SPM EL-0.306 HS ......... (Equation 2)

division Coefficient SE error T P value VIF a constant 537.99 77.84 6.91 0.000 Speed 0.28103 0.08652 3.25 0.005 1.3 SPM EL -7.613 17.351 -1.04 0.315 1.6 HS -0.30631 0.08800 -3.481 0.003 1.3

S = 4.174 R-Sq = 59.4% R-Sq (adj) = 52.2%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 433.07 144.36 8.29 0.001 Residual Error 17 296.17 17.42 Total 20 729.24

All. Elongation (EL)

EL = 67.6 + 0.0494 Speed-6.66 SPM EL-0.0217 HS ........ (Equation 3)

division Coefficient SE error T P value VIF a constant 67.64 34.83 1.94 0.069 Speed 0.04938 0.03871 1.28 0.219 1.3 SPM EL -6.656 3.289 -2.02 0.059 1.6 HS -0.02169 0.03937 -0.55 0.589 1.3

S = 1.867 R-Sq = 20.6% R-Sq (adj) = 6.6%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 15.382 5.127 1.47 0.258 Residual Error 17 59.284 3.487 Total 20 74.667

(2) low carbon steel

end. Yield Strength (YP)

YP = 1075 + 0.874 Speed -73.5 SPM EL-0.984 HS ........ (Equation 4)

division Coefficient SE error T P value VIF a constant 1074.7 574.0 1.87 0.202 Speed 0.8743 0.6012 1.45 0.283 1.0 SPM EL -73.52 20.13 -3.65 0.067 1.1 HS -0.9845 0.7312 -1.35 0.310 1.1

S = 24.26 R-Sq = 88.7% R-Sq (adj) = 71.8%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 9255.9 3085.3 5.24 0.164 Residual Error 2 1177.6 588.8 Total 5 10433.5

I. Tensile Strength (TS)

TS = 542 + 0.290 Speed-27.0 SPM EL-0.208 HS ...... (Equation 5)

division Coefficient SE error T P value VIF a constant 542.1 250.6 2.16 0.163 Speed 0.2904 0.2624 1.11 0.384 1.0 SPM EL -27.032 8.787 -3.08 0.091 1.1 HS -0.20821 0.3192 -0.65 0.581 1.1

S = 10.59 R-Sq = 84.7% R-Sq (adj) = 61.7%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 1238.4 412.8 3.68 0.221 Residual Error 2 224.4 112.2 Total 5 1462.8

All. Elongation (EL)

EL = -15.0 + 0.0192 Speed + 3.80 SPM EL + 0.0621 HS ..... (Equation 6)

division Coefficient SE error T P value VIF a constant -15.01 18.49 -0.81 0.502 Speed 0.01915 0.01937 0.99 0.427 1.0 SPM EL 3.7987 0.6485 5.86 0.028 1.1 HS 0.06207 0.02355 2.64 0.119 1.1

S = 0.7817 R-Sq = 94.6% R-Sq (adj) = 86.6%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 21.6113 7.2038 11.79 0.079 Residual Error 2 1.2220 0.6110 Total 5 22.8333

(3) high tensile strength steel

end. Yield Strength (YP)

YP = 190-0.163 Speed + 35.2 SPM EL + 0.012 HS ........ (Equation 7)

division Coefficient SE error T P value VIF a constant 190.0 227.4 0.84 0.450 Speed -0.1632 0.2586 -0.63 0.562 1.1 SPM EL 35.16 13.29 2.65 0.057 1.1 HS 0.0122 0.2614 0.05 0.965 1.1

S = 6.915 R-Sq = 69.2% R-Sq (adj) = 46.1%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 430.25 143.42 3.00 0.158 Residual Error 4 191.25 47.81 Total 7 621.50

I. Tensile Strength (TS)

TS = 1032-29.6 Speed-2642 SPM EL + 5.3 HS ......... (Equation 8)

division Coefficient SE error T P value VIF a constant 1032 3984 0.26 0.839 Speed -29.60 42.31 -0.70 0.611 162.6 SPM EL -2642 3168 -0.83 0.557 60.5 HS 5.31 12.25 0.431 0.740 57.5

S = 30.27 R-Sq = 79.3% R-Sq (adj) = 17.2%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression 3 3506.8 1168.9 1.28 0.559 Residual Error One 916.0 916.0 Total 4 4422.8

All. Elongation (EL)

EL = -144 + 0.224 HS ........... (Equation 9)

division Coefficient SE error T P value a constant -144.3 154.3 -0.94 0.418 HS 0.2241 0.1839 1.22 0.310

S = 3.444 R-Sq = 33.1% R-Sq (adj) = 10.8%

Performing analysis of variance using the above results is shown in the following table.

Source DF SS MS F P Regression One 17.61 17.61 1.48 0.310 Residual Error 3 35.59 11.86 Total 4 53.20

The equations of the above formulas (1) to (9) are expressed as determinants as follows.

end. For deep processing

I. In case of low carbon steel

All. In the case of high strength steel

Then, in order to obtain the optimum working conditions according to the material characteristics of each steel type, that is, the line speed, the tempered rolling elongation (SPM EL), and the annealing furnace heating temperature (HS), the inverse matrix of each steel type is used. Obtained as follows.

end. For deep processing

Solving the inverse of the core material is as follows.

Speed = 3.16 YP-1.79 TS + 16.8 EL-647

SPM EL = 0.015 YP + 0.0029 TS-0.082 EL + 1.73

HS = 2.52 YP-4.99 TS + 17.5 EL + 1124

I. In case of low carbon steel

Solving the inverse of the low carbon steel as follows.

Speed = 1.18 YP-1.1 TS + 15 EL-447

SPM EL = 0.029 YP-0.097 TS + 0.138 EL + 24

HS = -2.16 YP + 6.29 TS + 3.04 EL-1041

All. In the case of high strength steel

Solving the inverse of the high tensile strength steel is as follows.

Speed = -1.79 YP-0.024 TS + 0.662 EL + 154

SPM EL = 0.02 YP-0.00011 TS + 0.00154 EL-3.5

HS = 4.46 EL + 642.2

As described above, the material properties (YP) using the material properties measured by the on-line material measuring device 32 shown in FIG. 3, that is, yield strength (YP), tensile strength (TS), and elongation (EL) data. , TS, EL), and the steel condition, that is, annealing furnace line speed, tempered rolling elongation (SPM EL) and annealing furnace heating temperature (HS) are calculated. When receiving information on the type of steel sheet from the upper computer 31 as described above is to calculate the working conditions corresponding to each divided into deep processing, low carbon steel, high tensile strength steel. In this case, since the calculated working condition for each steel type is a calculated value without applying a compensation value according to the size of the steel sheet, a correction coefficient is applied to each steel type calculation formula according to the information on the size of the steel sheet from the upper computer 31. Apply the target value range of material properties according to the steel grade. The range of target values of the correction coefficient and the material properties according to the size of the steel sheet is as follows.

<Steel Plate Size Correction Factor (A)>

division thickness 0.4-0.8 mm <1.2 mm <1.6 mm <2.0 mm <2.4 mm width 800-1000 mm 1.60 1.30 1.00 0.80 0.60 <1200 mm 1.60 1.30 1.00 0.80 0.60 <1400 mm 1.50 1.20 0.90 0.80 0.60 <1600 mm 1.50 1.20 0.90 0.80 0.60 <1800 mm 1.40 1.10 0.80 0.80 0.60 <2000 mm 1.40 1.10 0.80 0.80 0.60

<Material Target Value>

division YP (㎏ / ㎠) TS (㎏ / ㎠) EL (%) Deep processing ≤17 ≥28 ≥44 Low carbon steel 21 to 32 32-40 ≥30 High strength steel 19 to 27 35 to 40 ≥38

When the YP, TS, and EL values measured by the online material measuring machine 32 are different from the target values of the material properties using the tables, working conditions (Speed, SPM EL and HS) is shown in the final formula as follows.

end. Deep processing ............. (Eq. 10)

Speed = 3.16 (17-YP)-1.79 (28-TS) + 16.8 (44-EL) + (100 × A)

SPM EL = 0.015 (17-YP) + 0.0029 (28-TS)-0.082 (44-EL) + 1.2

HS = 2.52 (17-YP)-4.99 (28-TS) + 17.5 (44-EL) + 850

I. Low carbon steel ...... (Eq. 11)

Speed = 1.18 (21-YP)-1.1 (32-TS) + 15 (30-EL) + 100 × A

SPM EL = 0.029 (21-YP)-0.097 (32-TS) + 0.138 (30-EL) + 1.5

HS = -2.16 (21-YP) + 6.29 (32-TS) + 3.04 (30-EL) + 760

All. High tensile strength ...... (Eq. 12)

Speed = -1.79 (19-YP)-0.024 (35-TS) + 0.662 (38-EL) + 100 × A

SPM EL = 0.02 (19-YP)-0.00011 (35-TS) + 0.00154 (38-EL) + 1.5

HS = 4.46 (38-EL) + 810

In this way, the working conditions (Speed, SPM EL, HS) according to the material characteristics (YP, TS, EL) are calculated for each steel type.

Hereinafter, a process for setting working conditions according to an embodiment of the present invention will be described.

EXAMPLE

end. Deep processing

If the size is 1.2mm × 1100mm, the current YP is 18kg / mm2, the TS is 27kg / mm2, and the EL is 43% deep processing (i.e., the steel sheet currently being measured may cause material defects), The process working condition is changed as follows by the control system of the annealing process for performing the process working condition setting process according to the present invention.

(In general, for 1.2mm × 1100mm deep steel, line speed: 120 ~ 140mm, SPM EL: ≤1.2%, annealing temperature: 840 ~ 850 ℃)

Speed = 3.16 (17-18)-1.79 (28-27) + 16.8 (44-43) + 100 × 1.0 = 112 mpm

SPM EL = 0.015 (17-18) + 0.0029 (28-27)-0.082 (44-43) + 1.2 = 1.1%

HS = 2.52 (17-18)-4.99 (28-27) + 17.5 (44-43) + 850 = 860 ° C

By changing to the above working conditions it is possible to ensure a normal material.

I. Low carbon steel

If the size is 1.2mm × 1100mm, low carbon steel with current YP of 20kg / mm2, TS of 31kg / mm2, and EL of 29% (i.e., the steel sheet currently being measured may cause material defects), The process working condition is changed as follows by the control system of the annealing process for performing the process working condition setting process according to the present invention.

(In general, for 1.2mm × 1100mm low carbon steel, line speed: 120 ~ 140mm, SPM EL: ≤1.5%, annealing temperature: ≤770 ℃)

Speed = 1.18 (21-20)-1.1 (32-31) + 15 (30-29) + 100 × 1.0 = 115 mpm

SPM EL = 0.029 (21-20)-0.097 (32-31) + 0.138 (30-29) + 1.5 = 1.57%

HS = -2.16 (21-20) + 6.29 (32-31) + 3.04 (30-29) + 760 = 767 ° C

By changing to the above working conditions it is possible to ensure a normal material.

All. High tension field

If the size is 1.2mm × 1100mm, the current YP is 18kg / mm2, the TS is 34kg / mm2, and the EL is 37% high tensile steel (i.e., the steel sheet being measured may cause material defects), The process working condition is changed as follows by the control system of the annealing process for performing the process working condition setting process according to the present invention.

(In general, for 1.2mm × 1100mm high strength steel, line speed: 120 ~ 140mm, SPM EL: ≥1.2%, annealing temperature: 830 ℃)

Speed = -1.79 (19-18)-0.024 (35-34) + 0.662 (38-37) + 100 × 1.0 = 99 mpm

SPM EL = 0.029 (19-18)-0.097 (35-34) + 0.138 (38-37) + 1.5 = 1.57%

HS = 4.46 (38-37) + 810 = 814 ° C

By changing to the above working conditions it is possible to ensure a normal material.

4 is a flowchart showing a process of setting an annealing furnace process working conditions using steel sheet material properties in the annealing process according to the present invention. 4, first, the type of steel sheet to be annealed in the host computer 31 and the size of the steel sheet are set (S41). The annealing furnace process working conditions (line speed, tempered rolling elongation and annealing furnace heating temperature) according to the information on the type and size of the set steel sheet are set, and annealing operation is executed according to the set working conditions (S42).

On the other hand, when the steel sheet is drawn into the annealing furnace 15 and the annealing operation is completed (S43), the material characteristics of the steel sheet completed the annealing operation in the on-line material measuring machine 32 installed at the rear end of the annealing furnace 15, Yield strength (YP), tensile strength (TS) and elongation (EL) are measured (S44). It is determined whether the measured material characteristic matches a predetermined material characteristic target value (S45). If the determination result in the step (S45) and the material property measurement value and the target value is the same, the annealing operation is performed while maintaining the working condition set in the step (S42) (S46).

However, if the determination result in the step (S45) does not match the measured value of the material properties and the target value is calculated by calculating the working conditions for each steel type according to the measured value as shown in the above (Equation 10) ~ (Equation 12) (S47) It is again applied to the annealing furnace process (S48).

In this way, the information (size and type) of the steel sheet to be worked is received from the upper computer 31 and the material characteristics (YP, TS, EL) of the steel sheet after the annealing operation are measured, and the measured value and If the set material property target value is different, the new annealing furnace process working conditions (Speed, SPM EL, HS) are set using the material property measurement values using Equation 10 to Equation 12. The difference can be resolved.

The detailed description and drawings of the present invention disclose a preferred embodiment to help understand the present invention, and do not limit the scope of the present invention, and the scope of the present invention is determined by the above detailed description. Rather, it should be determined in the appended claims.

According to the present invention, it is possible to set the working conditions according to the material characteristics by feeding back the current material characteristics of the steel sheet completed annealing in real time, and also because the operating conditions of the annealing furnace process can be controlled in real time according to the material changes the line Even in the event of disturbances, it is possible to output the optimum working conditions so that homogeneous materials can be secured.

The above detailed description and contents disclosed in the drawings are not intended to limit the present invention, and it is apparent to those skilled in the art that various modifications and changes can be made without departing from the spirit of the present invention. will be.

Claims (3)

A correlation calculation step of setting a working condition of an annealing furnace process influencing the material properties of the steel sheet by the type and size of the steel sheet, and calculating a correlation between the material properties of the steel sheet and the working condition of the annealing furnace process; A material property detection step of detecting material properties of the steel sheet after the annealing operation is completed; A material property comparison step of comparing a material property detection value of the work steel sheet with a material property target value of a predetermined steel sheet; And If the two values match, the current condition is maintained, and if not, the operating condition of the annealing furnace process is reset using the calculated correlation using the calculated correlation. Method for setting the annealing furnace process working conditions using the material properties of the steel sheet, characterized in that it comprises a step. The method of claim 1, wherein the working condition, Line speed (Speed), temper rolling elongation (SPM EL) and annealing furnace heating temperature (HS) characterized in that the method of setting the operating conditions of the annealing furnace process using the material characteristics of the steel sheet. The method of claim 1, wherein the material properties of the steel sheet, Method for setting the working conditions of the annealing furnace process using the material properties of the steel sheet characterized by the yield strength (YP), tensile strength (TS) and elongation (EL).