KR20160143921A - Continuous casting and rolling apparatus and method - Google Patents

Abstract

According to an embodiment of the present invention, a continuous casting and rolling apparatus comprises: a continuous casting mill producing a slab; a rolling mill having a roughing mill disposed on a discharge side of the continuous casting mill and a finishing mill disposed on a discharge side of the roughing mill, and pressing the slab; a cutter disposed on at least one of an entry side of the roughing mill or an entry side of the finishing mill; and a controller electrically connected to the cutter to control driving of the cutter, and determining whether to switch between a continuous rolling mode in which the slab is continually provided to the continuous casting mill and the rolling mill and a discontinuous rolling mode in which the slab is cut by the cutter to select the continuous rolling mode or the discontinuous rolling mode. The controller can satisfy the following formula in a case in which the controller selects the continuous rolling mode. Here, H is the thickness (mm) of a slab on the discharge side of the continuous casting mill, V is the rate (m/min) of the slab on the discharge side of the continuous casting mill, L is the length (m) from the discharge side of the continuous casting mill to the discharge side of the finishing mill, T is the average temperature (C) of the slab on the discharge side of the continuous casting mill, N_R is the number of stands of the roughing mill, N_F is the number of stands of the finishing mill, and t is the thickness (mm) of the slab on the discharge side of the finishing mill. [formula] HV > (L/((T/2295) - (1/153)N_R - (2/459)N_F - (17/4074)*(t-2) - (50/153)))

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a continuous rolling and rolling apparatus,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a performance rolling apparatus and a performance rolling method, and more particularly to an invention for selecting switching between a continuous rolling mode and a discontinuous rolling mode.

The process of rolling in a rolling mill using high temperature of cast steel solidified in a casting machine is widely used now because the equipment cost and the operating cost are inexpensive compared with the existing processes.

It is also possible to carry out a discontinuous process in which continuous casting and rolling are continuously used and rolling separately from the continuous casting, which is described in Korean Patent Publication No. 1990-7001437.

That is, the continuous casting process and the rolling process can be performed continuously in the continuous rolling mode, the continuous casting process, and the continuous rolling mode in which the rolling process is discontinuously performed.

In the continuous rolling mode, the rolling process in the rolling mill is dependent on the casting production speed and the like in the continuous casting machine, while the discontinuous rolling mode is provided in a continuous state between the continuous casting machine and the rolling mill. Therefore, the degree to which the rolling process in the rolling mill is dependent on the performance is relaxed rather than the continuous rolling mode.

As such, the continuous rolling mode and the discontinuous rolling mode may have different process states. In the past, the selection of the continuous rolling mode and the discontinuous rolling mode was arbitrary and was not selected by a clear standard.

That is, conventionally, it has been trial and error to confirm whether the continuous rolling mode or the discontinuous rolling mode is possible through actual operation. In other words, the process was carried out in the continuous rolling mode, and then the state of the rolled steel sheet discharged was checked.

However, the selection of the mode by trial and error has a waste point to produce unnecessary defective products before the mode selection, and if the continuous rolling mode or the discontinuous rolling mode is selected without considering the state of the casting, A problem that can not be secured can be caused.

Therefore, there is a need to study a performance rolling apparatus and a performance rolling method for solving the above-mentioned problems.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a performance rolling apparatus and a performance rolling method capable of producing a rolled steel plate product with quality assured by selecting switching between a continuous rolling mode and a discontinuous rolling mode.

A casting rolling apparatus according to an embodiment of the present invention includes a casting machine for producing a cast steel, a roughing mill located on the outgoing side of the casting mill and a finishing mill located on the outside of the roughing mill, A continuous rolling mode in which a cutter positioned at least one of an inlet side and an inlet side of the finishing mill and a main rolling element provided in a continuous machine in the continuous casting machine and the rolling mill are electrically connected to the cutter to adjust driving of the cutter, And a controller for determining whether to switch the discontinuous rolling mode for cutting the slab and selecting the continuous rolling mode or the discontinuous rolling mode, wherein when the controller selects the continuous rolling mode, the following equation is satisfied can do.

In this case, H is the thickness of the cast steel at the casting out side (mm), V is the casting speed at the casting out side (m / min), L is the length from the casting out side to the finishing rolling mill outgoing side (m), T is the casting average temperature (° C), N _R is the number of stands of the roughing mill, N _F is the number of stands of the finishing mill, and t is the thickness of the fin (mm) on the side of the finishing mill.

Further, the apparatus further includes a heater located at an inlet side of at least one of the rough rolling mill and the finishing rolling mill of the performance rolling apparatus according to an embodiment of the present invention, wherein when the controller selects the continuous rolling mode, .

Here, W is the casting width (mm) at the casting exit side, and E _H is the calorie consumption (MW).

The scale rolling mill according to one embodiment of the present invention further comprises a scale remover having a first scale remover located on the rough rolling mill side of the rough rolling mill and a second scale remover located on the side of the finishing mill, When the continuous rolling mode is selected, the following equation can be satisfied.

Here, P _R is a pressure applied to the first scale remover (bar), and P _F is a pressure (bar) applied to the second scale remover.

According to another aspect of the present invention, there is provided a method of casting a casting, comprising the steps of casting a cast steel in a continuous casting machine, rolling the cast steel to a rolling mill, and continuously rolling the continuous casting And a mode selecting step of selecting a transition of the discontinuous rolling mode in which the main cutting is performed before or during the rolling step, before the rolling step, wherein the mode selecting step is a step in which the temperature at the exit side of the rolling mill, Is conducted in a continuous rolling mode when the temperature is higher than a temperature that can be provided in the austenitic state and when the temperature at the exit side of the rolling mill is lower than a temperature at which the main body can be provided in the austenitic state, .

According to another embodiment of the present invention, there is provided a method of casting a cast steel, comprising the steps of casting a cast steel in a casting machine, rolling the cast steel to a roughing mill located on the outgoing side of the casting mill, And a mode selection step of selecting a transition between a continuous rolling mode in which the main strip is provided as a continuum in the casting step and a rolling step and a discontinuous rolling mode in which the main strip is cut off before or during the rolling step before the rolling step And the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode when it is unsatisfactory.

In this case, H is the thickness of the cast steel at the casting out side (mm), V is the casting speed at the casting out side (m / min), L is the length from the casting out side to the finishing rolling mill outgoing side (m), T is the casting average temperature (° C), N _R is the number of stands of the roughing mill, N _F is the number of stands of the finishing mill, and t is the thickness of the fin (mm) on the side of the finishing mill.

According to another embodiment of the present invention, there is provided a method of casting a cast steel, comprising the steps of casting a cast steel in a casting machine, rolling the cast steel to a casting mill located on the out side of the casting mill, A heating step of heating the cast steel by a heater located at an inlet side of at least one of the rough rolling mill and the finishing mill, a first scale remover located at the entrance of the rough rolling mill, and a second scale remover located at the entrance of the finishing mill A scale removing step of removing scale on the surface of the slab, a continuous rolling mode in which the main slab is provided as a continuous body in the casting step and the rolling step, and a switching of the discontinuous rolling mode in which the slab is cut during the rolling step or during the rolling step And a mode selection step of selecting before the rolling step, A casting speed at the casting out side, a casting speed at the casting out side, a length from the casting out side to a finishing mill output side, a casting heat amount, an average temperature of the casting at the casting out side, a stand number of the rough rolling mill, The continuous rolling mode and the discontinuous rolling mode are selected and performed based on the number of rolls, the pressure applied to the first scale remover, the pressure applied to the second scale remover, and the thickness of the slab at the exit side of the finishing rolling mill.

Further, the mode selection step of the performance rolling method according to another embodiment of the present invention is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode when unsatisfactory: can do.

Where H is the slab thickness (mm) at the exit side of the runner, W is the slab width (mm) at the exit side of the runner, V is the slab speed at the exit side of the runner (m / min), L is the length ), E _H is a primary side heat (MW), T is a caster cast average temperature (℃) side output receive, N _R is the stand of the roughing mill, N _F can stand the spirit mill, P _R is the first scale (Bar), P _F is the pressure applied to the second scale remover (bar), and t is the thickness of the billet on the exit side of the finishing mill (mm).

Further, in the performance rolling method according to another embodiment of the present invention, the stand number N _R of the rough rolling mill is 0 to 3, the stand number N _F of the finish rolling mill is 5 to 7, The pressure P _R applied to the scale remover is 0 to 200 bar, the pressure P _F applied to the second scale remover is 200 to 300 bar, and the thickness t of the cast steel at the exit side of the finishing mill is 1.0 to 3.0 mm, the mode selection step is performed in the continuous rolling mode when the following equation is satisfied, and in the discontinuous rolling mode if it is unsatisfactory.

Here, A is 0.3553 to 0.4247.

Further, in the performance rolling method according to another embodiment of the present invention, when the heat amount E _{H to} be subjected to the main cutting is 10 to 25 MW, the mode selection step is performed in a continuous rolling mode when the following formula is satisfied And if it is unsatisfactory, the discontinuous rolling mode is selected and performed.

Here, A is 0.3553 to 0.4247, and B is 39020 to 97550.

Further, in the performance rolling method according to another embodiment of the present invention, the average temperature (T) at the exit side of the performance machine is 1000 to 1250 DEG C, the stand number (N _R ) of the rough rolling mill is 3, The number N _F is 5, the pressure P _R applied to the first scale remover is 200 bar, the pressure P _F applied to the second scale remover is 300 bar, and the thickness of the casting at the exit side of the finishing mill (t) is 1.5 mm, the mode selection step is performed in the continuous rolling mode when the following equation is satisfied, and in the discontinuous rolling mode if it is unsatisfactory.

Here, C is 0.0315 to 0.1404.

The performance rolling apparatus and the performance rolling method of the present invention can have the effect of securing the quality of the rolled steel plate product when the switching between the continuous rolling mode and the discontinuous rolling mode is selected.

In addition, unnecessary pre-trial and error processes for selection of the continuous rolling mode and the discontinuous rolling mode are unnecessary, and it is possible to reduce the waste of the casting by the trial and error process.

1 is a side view showing a performance rolling apparatus of the present invention.
Fig. 2 is a flowchart showing a performance rolling method of the present invention.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the inventive concept. Other embodiments falling within the scope of the inventive concept may readily be suggested, but are also considered to be within the scope of the present invention.

The same reference numerals are used to designate the same components in the same reference numerals in the drawings of the embodiments.

The performance rolling apparatus and the performance rolling method of the present invention relate to an invention for selecting switching between a continuous rolling mode and a discontinuous rolling mode.

That is, the performance rolling apparatus and the performance rolling method of the present invention are inventions capable of ensuring the quality of the rolled steel plate product when the switching between the continuous rolling mode and the discontinuous rolling mode is selected.

In addition, unnecessary pre-trial and error processes for selection of the continuous rolling mode and the discontinuous rolling mode are unnecessary, and it is possible to reduce the waste of the casting by the trial and error process.

In more detail, a performance rolling apparatus according to an embodiment of the present invention includes a performance machine 10 for producing a cast steel, a rough rolling mill 21 located on the outer side of the performance machine 10, A cutting machine (30) comprising a rolling mill (22), a rolling mill (20) for rolling the slab, a cutter (30) located at an inlet of the roughing mill (21) or at an inlet of the finishing mill And a continuous rolling mode in which the main cutting edge is provided as a continuous body in the mill 10 and the rolling mill 20 by adjusting the drive of the cutter 30 and a discontinuous And a controller (60) for determining whether the rolling mode is switched or not and selecting the continuous rolling mode or the discontinuous rolling mode, wherein when the controller (60) selects the continuous rolling mode, the following equation It can be characterized as The.

[ Equation 1 ]

Where H is the slab thickness (mm) on the exit side of the continuous casting machine 10, V is the slab speed (m / min) on the exit side of the continuous casting machine 10, L is the length from the exit of the finisher 10 to the exit side of the finish rolling mill 22 m), t is a caster (10) side output cast average temperature (℃), N _R is the stand of the roughing mill (21), N _F can stand the spirit rolling mill (22), t is the spirit mill 22 (Mm) of the casting at the exit side.

Thus, satisfying the above expression (1) can be achieved when the temperature at the exit side of the finishing mill 22 is higher than the temperature at which the steel sheet or the final rolled steel sheet can be provided in the austenitic state, It is possible to secure the quality of the product. The following equations are presented for the same reason.

The casting machine 10 may serve to produce a cast steel from molten steel through a casting process. That is, the casting machine 10 supplies molten steel from the tundish to the casting mold, and the supplied molten steel is stripped of heat to form a casting. The casting is performed by a segment roll and a pinch roll Guided and moved and fed to a rolling mill 20 to be described later.

However, it is difficult to control the production rate because such a continuous casting machine 10 produces a steel strip depending on the solidification speed of the molten steel. Therefore, it is a speed limitation to produce the product by successively receiving the slabs produced in the continuous casting machine 10 and pressing the slabs with the rolling mill 20 to be described later.

However, since the cast steel discharged from the continuous casting machine 10 has a high average temperature, there is an advantage that the rolling mill 20 can secure a certain temperature required for the rolling operation.

The rolling mill 20 can take the role of producing the rolled steel sheet by receiving the cast steel produced in the continuous casting machine 10. For this purpose, the rolling mill 20 can be rolled while passing the slabs through a pair of rolling rolls, and a rolling stand provided with such rolling roll pairs can be provided.

The rolling mill 20 includes a rough rolling mill 21 for rolling a slab provided in the milling machine 10 to an intermediate thickness before being produced into a finished rolled steel strip product having a final thickness, ) To produce a rolled steel sheet having a final thickness again.

Here, the roughing mill 21 is located on the exit side of the milling machine 10, and receives the slabs produced by the milling machine 10 to perform a rolling operation. The milling mill 22 is connected to the roughing mill 21), and receives the cast steel subjected to the rolling work in the roughing mill (21) to perform rolling, thereby performing a rolling operation for producing the final rolled steel product.

In particular, the number of rolling stands provided in the rough rolling mill 21 and the finishing rolling mill 22 can be adjusted according to the characteristics of the material of the rolled steel sheet to be produced, The number of rolling stands secured by the rolling machine 22 is not the number of rolling stands provided by the roughing mill 21 or the finishing rolling mill 22, And the number of rolling stands provided by the rolling mill 21 or the finishing mill 22.

The cutter 30 may be provided for cutting the casting at an intermediate portion of a performance rolling apparatus, for carrying out in a discontinuous rolling mode.

That is, the cutter 30 may be located at the entrance of the roughing mill 21 or at the entrance of the mill 22, and more particularly, between the roughing mill 21 and the milling machine 10, At least one of the positions between the finishing mill 22 and the roughing mill 21 can be provided.

In addition, the cutter 30 may be additionally provided on the exit side of the finishing mill 22 in order to discharge the final finished rolled steel sheet product by pressing down the main cutting edge.

Particularly, the cutter 30 is electrically connected to a controller 60, which will be described later, so as to perform cutting of the cast steel. This is accomplished by selecting the continuous rolling mode or the discontinuous rolling mode in the controller 60 to be.

That is, when the controller 60 instructs the operation of the cutter 30 to cut the cast steel, it is performed in the discontinuous rolling mode, and the controller 60 instructs the operation of the cutter 30 The cast steel is provided as a continuum from the casting machine 10 to the rolling mill 20 to perform the continuous rolling mode.

Here, when the controller 60 does not drive the cutter 30 and the continuous rolling mode is selected and performed, the equation (1) must be satisfied.

That is, in the case where the above formula (1) is not satisfied, the rolled steel sheet product produced in the continuous rolling mode is produced as a defective product and is discarded without being used.

In addition, the performance rolling apparatus of the present invention may further include a heater 40, a scale remover 50, and the like to perform the performance rolling process.

That is, the apparatus further includes a heater (40) positioned at the entrance of at least one of the rough rolling mill (21) and the finishing mill (22) of the performance rolling apparatus according to an embodiment of the present invention, When the rolling mode is selected, the following equation (2) can be satisfied.

[ Equation 2 ]

Here, W is the billet width (mm) on the exit side of the player 10, and E _H is the heat quantity (MW) to which the bill is fed.

When the heater 40 is not sufficient for the rolling of the rolling mill 20 due to the heat contained in the main body fed from the continuous casting machine 10, And the temperature is raised to a temperature necessary for rolling to perform rolling.

For this, the heater 40 may be provided with a burner in a heating furnace, but is preferably provided in the form of induction heating to be heated by an induction coil to facilitate control of the heating temperature.

The heater 40 is preferably provided at the entrance of the roughing mill 21 or the finishing mill 22 and more specifically the position between the milling cutter 30 and the roughing mill 21, (21) and the finishing mill (22).

Particularly, when the performance rolling apparatus including such a heater 40 is performed in the continuous rolling mode, the above formula (2) must be satisfied. This means that the final rolled steel sheet product is produced as a defective product, .

A first scale remover 51 located at the entrance of the rough rolling mill 21 and a second scale remover 52 located at the entrance of the finishing rolling mill 22 of the casting rolling apparatus according to an embodiment of the present invention, And a scale eliminator (50) having a controller (60), wherein when the controller (60) selects the continuous rolling mode, the following equation (3) is satisfied.

[ Equation 3 ]

Here, P _R is the pressure (bar) applied to the first scale remover 51, and P _F is the pressure (bar) applied to the second scale remover 52.

Further, the scale remover 50 serves to remove foreign matters on the surface of the cast steel. For this purpose, the scale remover 50 removes foreign substances on the surface of the cast steel, ) Or the scale finishing before the slab enters the finishing mill (22).

That is, the scale remover 50 can provide the first scale remover 51 at the entrance of the roughing mill 21 and the second scale remover 52 at the entrance of the finishing mill 22.

In particular, when the performance rolling apparatus including such a heater 40 is performed in the continuous rolling mode, the above formula (3) must be satisfied. This means that the final rolled steel sheet product is not produced and used as a defective product, .

For example, H is 80 mm, W is 1000 mm, V is 6.5 m / min, L is 100 m, E _H is 10 MW, T is 1200 ° C, N _R is 3, N _F is 5, P _R is 200 bar, P _F is 300 bar and t is 1.5 mm, the above equation (3) is satisfied as "520000 > 495395 ", so that the quality of the rolled steel sheet can be secured even in the continuous rolling mode.

Hereinafter, a performance rolling method, which is another embodiment, in addition to the performance rolling apparatus, which is one embodiment of the present invention, will be described.

That is, a method of casting rolling according to another embodiment of the present invention includes a casting step of producing a cast steel in the continuous casting machine 10, a rolling step of rolling the cast steel into a rolling mill 20, And a mode selection step of selecting a transition of a discontinuous rolling mode in which the main section is cut before or during the rolling step before the rolling step, ) Is performed in a continuous rolling mode when the temperature at the exit side of the rolling mill (20) is above the temperature at which the main slab can be provided in the austenitic state, and the temperature at the exit side of the rolling mill And when the temperature is lower than the predetermined temperature, the discontinuous rolling mode is selected.

The continuous casting step is a step of producing the cast steel by the casting machine 10, and the cast steel is received by continuous casting to provide the cast steel. At this time, the slab formed at the beginning of the continuous casting step is provided to the rolling mill 20 to perform the rolling step.

The rolling step is a step of producing a product of rolled steel sheet by receiving the cast steel produced in the continuous casting step.

Here, the rolling step may be performed by the rough rolling mill 21 and the finishing mill 22 in the rough rolling step and the finishing rolling step. That is, a rough rolling step of rolling at an intermediate thickness as an intermediate stage of the final rolled steel sheet thickness in the rough rolling mill 21 provided on the output side of the machine tool 10 and a rough rolling step 22) in which rolling is performed at the thickness of the final rolled steel sheet.

The mode selection step is a step of selecting the continuous rolling mode and the discontinuous rolling mode, and the mode selection step is performed according to the temperature of the billet on the exit side of the rolling mill 20.

That is, in the case where the temperature of the slab discharged from the rolling mill 20 to the exit side of the finishing mill 22 is equal to or higher than the temperature at which it can be supplied in the austenitic state, the continuous rolling mode is performed, When the temperature of the casting is lower than the temperature that can be provided in the austenitic state, it is performed in the discontinuous rolling mode.

The mode of selecting the continuous rolling mode or the discontinuous rolling mode is defined as whether or not the rolling step is performed with the cut slab, and the execution of the mode selecting step should be performed at least before the rolling step.

More specifically, the mode selection step is preferably performed before the rough rolling step or the finishing rolling step.

Therefore, the mode selection step may be performed before the continuous casting step because it is performed before the rolling step.

The method for casting rolling according to another embodiment of the present invention includes a casting step for producing a cast steel in a continuous casting machine 10, a casting step for casting the cast steel in the casting mill 10, A continuous rolling mode in which the cast slab is cut by a finishing mill 22 and a continuous rolling mode in which the main slab is provided as a continuum in the casting step and the rolling step, and a continuous rolling mode in which the main slab is cut during the rolling step or during the rolling step Wherein the mode selection step is performed in a continuous rolling mode when the following expression (4) is satisfied, and in the case of dissatisfaction, a discontinuous rolling mode is selected Is performed.

[ Equation 4 ]

Where H is the slab thickness (mm) on the exit side of the continuous casting machine 10, V is the slab speed (m / min) on the exit side of the continuous casting machine 10, L is the length from the exit of the finisher 10 to the exit side of the finish rolling mill 22 m), t is a caster (10) side output cast average temperature (℃), N _R is the stand of the roughing mill (21), N _F can stand the spirit rolling mill (22), t is the spirit mill 22 (Mm) of the casting at the exit side.

That is, the mode selection step may be performed by selecting the continuous rolling mode and the discontinuous rolling mode based on Equation (4).

The equation (4) is satisfied only when the heating step and the descaling step are not included, and when the heating step and the descaling step are included, it should be determined by the following equation (5).

That is, a method of casting rolling according to another embodiment of the present invention includes a casting step of producing a cast steel in a continuous casting machine 10, a casting step of casting the cast steel in a casting mill 21 located on the outgoing side of the casting machine 10, A heating step of heating the cast steel with a heater (40) positioned at the side of at least one of the roughing mill (21) and the finishing mill (22), a heating step of heating the cast steel A scale removing step of removing a scale of the surface of the slab by a first scale remover 51 located at the entrance of the rolling mill 21 and a second scale remover 52 located at the entrance of the finishing rolling mill 22, And a mode selection step of selecting a transition between a continuous rolling mode in which the main yarn is provided as a continuum in the step and a rolling step and a discontinuous rolling mode in which the main yarn is cut off before or during the rolling step before the rolling step Wherein the mode selecting step includes a step of selecting a mode of the casting machine from a state in which the thickness of the casting on the exit side of the continuous casting machine, the casting body width on the exit side of the continuous casting machine, the casting speed on the exit side of the continuous casting machine, The average temperature of the cast steel at the exit side of the casting machine 10, the number of stands of the roughing mill 21, the number of stands of the finishing mill 22, the pressure applied to the first scale remover 51, The continuous rolling mode and the discontinuous rolling mode are selected based on the pressure applied to the eliminator 52 and the thickness of the billet at the exit side of the finishing mill 22.

The heating step is a step of heating the cast steel when the temperature of the cast steel does not reach the temperature for performing the rolling step.

Here, the heating step may be carried out before the rolling step or during the rolling step. In other words, it can be carried out before the roughing step during the rolling step or between the roughing step and the finishing step.

To this end, the heater 40 is provided at the entrance of the roughing mill 21 or at the entrance of the finishing mill 22 to perform heating on the casting.

The scale removing step may be performed by the scale remover 50 described above. Specifically, the first scale remover 51 on the side of the rough rolling mill 21 may remove the foreign substances on the surface of the cast steel, Or by a second scale remover 52 at the entrance of the finishing mill 22.

Here, the mode selection step of the performance rolling method according to another embodiment of the present invention is performed in a continuous rolling mode when the following expression (5) is satisfied, and in a discontinuous rolling mode when unsatisfactory .

[ Equation 5 ]

Where H is the slab thickness (mm) at the exit side of the continuous casting machine 10, W is the slab width (mm) at the exit side of the continuous casting machine 10, V is the slab speed at the exit side of the continuous casting machine 10 (m / min) 10) the length (m), E _H is a primary side heat (MW), T is a caster (10) side output cast average temperature (℃), N _R received at the outlet from the spirit rolling mill (22) outlet is roughing mill ( 21 is a stand number of the scale remover 52, N _F is the number of stands of the finishing mill 22, P _R is a pressure (bar) applied to the first scale remover 51, P _F is a pressure (bar), and t is the thickness of the billet (mm) on the exit side of the finishing mill 22.

In Equation (5), the influence of air cooling in the entire section, the influence of heating in the heater 40, the influence of the rough rolling in the rough rolling mill 21 and the finishing rolling mill 22, The influence of the scale removal process in the first scale remover 51 and the second scale remover 52 can be considered.

First, the effect of air cooling in the entire section is due to the heat transfer due to the temperature difference between the casting and the outside air, typically due to the hot staple being exposed in the air. In this case, conduction propagates the heat inside the material, and heat is transferred to the outside air by convection and radiation. V and L are representative variables.

Secondly, the influence of heating in the heater 40 is affected by heating by the amount of heat input to the casting in the heater 40, and the variable E _H is representative in consideration thereof.

Thirdly, the influence of the rolling in the rough rolling mill 21 and the finishing mill 22 takes into account the strain energy, the friction energy and the loss energy which are generated when the cast steel is pressed down. Generally, The amount of energy lost in the rolling rolls in the cast steel is larger than the temperature rising effect, resulting in a decrease in temperature. N _{R and} N _F are representative of these variables.

Fourth, the influence of the scale removal process in the first and second scale removers 51 and 52 is caused by the phenomenon of being cooled by the pressure applied by the scale remover 50, ), The capacity of removing scale is improved, but the amount of energy lost by the main body is increased, and the temperature of the cast steel is lowered. P _R and P _F represent the variables considered.

In the performance rolling method according to another embodiment of the present invention, the stand number N _R of the rough rolling mill 21 is 0 to 3, the stand number N _F of the finish rolling mill 22 is 5 to 7 The pressure P _R applied to the first scale remover 51 is 0 to 200 bar and the pressure P _F applied to the second scale remover 52 is 200 to 300 bar, When the thickness t of the casting sheet at the exit side of the casting 22 is 1.0 to 3.0 mm, the mode selecting step is performed in the continuous rolling mode when the following equation (6) is satisfied, and in the case of dissatisfaction rolling mode As shown in FIG.

[ Equation 6 ]

Here, A is 0.3553 to 0.4247.

Further, in the performance rolling method according to another embodiment of the present invention, in the case where the heat amount E _{H to} be subjected to the main cutting is 10 to 25 MW, the mode selecting step may include a continuous rolling mode , And when it is unsatisfactory, the discontinuous rolling mode is selected and carried out.

[ Equation 7 ]

Here, A is 0.3553 to 0.4247, and B is 39020 to 97550.

In the performance rolling method according to another embodiment of the present invention, the average temperature T at the exit side of the performance machine 10 is 1000 to 1250 ° C, and the stand number N _R of the roughing mill 21 is three , The number of stands N _F of the finishing mill 22 is 5, the pressure P _R applied to the first scale remover 51 is 200 bar, the pressure applied to the second scale remover 52 P _F is 300 bar and the thickness t of the cast steel at the exit side of the finishing mill 22 is 1.5 mm, the mode selection step is performed in the continuous rolling mode when the following equation (8) is satisfied , And when it is unsatisfactory, the discontinuous rolling mode is selected and performed.

[ Equation 8 ]

Here, C is 0.0315 to 0.1404.

In other words, the above Equations (6) to (8) are mathematical expressions summarized by substituting numerical values commonly used for non-critical variables among the variables of Equation (5) It is suggested to judge.

10: Player 20: Rolling machine
21: rough rolling machine 22: finishing mill
30: cutter 40: heater
50: scale remover 51: first scale remover
52: second scale remover 60: controller

Claims (10)

A casting machine for producing a cast steel;
A rolling mill having a rough rolling mill positioned on the exit side of the casting mill and a finishing mill located on the side of the rough rolling mill, the rolling mill rolling down the slab;
A cutter located at least one of an inlet side of the roughing mill or an inlet side of the finishing mill; And
A continuous rolling mode in which the main cutting edge is provided as a continuum in the continuous casting machine and the rolling mill, and a discontinuous rolling mode in which the casting is cut by the cutter, A controller for selecting the continuous rolling mode or the discontinuous rolling mode;
/ RTI >
Wherein when the controller selects the continuous rolling mode, the following expression is satisfied.

In this case, H is the thickness of the cast steel at the casting out side (mm), V is the casting speed at the casting out side (m / min), L is the length from the casting out side to the finishing rolling mill outgoing side (m), T is the casting average temperature (° C), N _R is the number of stands of the roughing mill, N _F is the number of stands of the finishing mill, and t is the thickness of the fin (mm) on the side of the finishing mill.
The method according to claim 1,
A heater positioned at an inlet side of at least one of the roughing mill and the finishing mill;
Further comprising:
Wherein when the controller selects the continuous rolling mode, the following expression is satisfied.

Here, W is the casting width (mm) at the casting exit side, and E _H is the calorie consumption (MW).
3. The method of claim 2,
A scale remover comprising a first scale remover located on the side of the roughing mill and a second scale remover located on the side of the finishing mill;
Further comprising:
Wherein when the controller selects the continuous rolling mode, the following expression is satisfied.

Here, P _R is a pressure applied to the first scale remover (bar), and P _F is a pressure (bar) applied to the second scale remover.
A casting step to produce a casting in the machine;
A rolling step of rolling the cast steel with a rolling mill; And
A mode selection step of selecting a continuous rolling mode in which the main part is provided as a continuum in the casting step and the rolling step and a discontinuous rolling mode in which the main part is cut off before or during the rolling step before the rolling step;
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Wherein the mode selection step comprises:
And the temperature at the exit side of the rolling mill is higher than a temperature at which the slab can be provided in the austenitic state,
And the discontinuous rolling mode is selected when the temperature at the exit side of the rolling mill is lower than a temperature at which the main body can be provided in the austenitic state.
A casting step to produce a casting in the machine;
A rolling step of rolling the cast steel by a roughing mill located on the exit side of the casting machine and a finishing mill located on the side of the roughing mill; And
A mode selection step of selecting a continuous rolling mode in which the main part is provided as a continuum in the casting step and the rolling step and a discontinuous rolling mode in which the main part is cut off before or during the rolling step before the rolling step;
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Wherein the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode if it is unsatisfactory.

In this case, H is the thickness of the cast steel at the casting out side (mm), V is the casting speed at the casting out side (m / min), L is the length from the casting out side to the finishing rolling mill outgoing side (m), T is the casting average temperature (° C), N _R is the number of stands of the roughing mill, N _F is the number of stands of the finishing mill, and t is the thickness of the fin (mm) on the side of the finishing mill.
A casting step to produce a casting in the machine;
A rolling step of rolling the cast steel by a roughing mill located on the exit side of the casting machine and a finishing mill located on the side of the roughing mill;
A heating step of heating the cast slab by a heater located at an inlet side of at least one of the rough rolling mill and the finishing mill;
A scale removing step of removing scale on the surface of the slab by a first scale remover located on the side of the rough rolling mill and a second scale remover located on the side of the finishing mill; And
A mode selection step of selecting a continuous rolling mode in which the main part is provided as a continuum in the casting step and the rolling step and a discontinuous rolling mode in which the main part is cut off before or during the rolling step before the rolling step;
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Wherein the mode selection step includes a step of selecting a mode of the cast iron rolling machine, wherein the mode selecting step includes the steps of: determining a casting thickness at a casting outgoing side, a casting width at a casting outgoing side, a casting speed at a casting outgoing side, The continuous rolling mode and the discontinuous rolling mode are selected and performed based on the number of stands, the number of stands of the finishing mill, the pressure applied to the first descaler, the pressure applied to the second scale remover, and the thickness of the slab on the exit side of the finishing mill .
The method according to claim 6,
Wherein the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode if it is unsatisfactory.

Where H is the slab thickness (mm) at the exit side of the runner, W is the slab width (mm) at the exit side of the runner, V is the slab speed at the exit side of the runner (m / min), L is the length ), E _H is a primary side heat (MW), T is a caster cast average temperature (℃) side output receive, N _R is the stand of the roughing mill, N _F can stand the spirit mill, P _R is the first scale (Bar), P _F is the pressure applied to the second scale remover (bar), and t is the thickness of the billet on the exit side of the finishing mill (mm).
8. The method of claim 7,
(N _R ) of the roughing mill is 0 to 3, the number of stands (N _F ) of the finishing mill is 5 to 7, and the pressure (P _R ) applied to the first descaler is 0 to 200 bar , The pressure P _F to be supplied to the second scale remover is 200 to 300 bar and the thickness t of the cast steel at the exit side of the finishing mill is 1.0 to 3.0 mm,
Wherein the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode if it is unsatisfactory.

Here, A is 0.3553 to 0.4247.
9. The method of claim 8,
In the case where the heat quantity (E _H ) to be subjected to casting is 10 to 25 MW,
Wherein the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode if it is unsatisfactory.

Here, A is 0.3553 to 0.4247, and B is 39020 to 97550.
8. The method of claim 7,
(N _R ) of the rough rolling mill is 3, the number of stands (N _F ) of the finishing mill is 5, and the average temperature (T) at the exit side of the performance machine is 1000 to 1250 ° C. pressure to be input to the (P _R) is 200bar, the second scale, and the pressure (P _F) is 300bar input into the remover, if the output state is thought mill convenience 1.5mm thickness (t) at the side,
Wherein the mode selection step is performed in a continuous rolling mode when the following expression is satisfied, and in a discontinuous rolling mode if it is unsatisfactory.

Here, C is 0.0315 to 0.1404.

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