[Technical Field]
[0001] The present disclosure relates to continuous casting and rolling equipment switching
between continuous rolling and batch rolling, capable of improving percentage yields
by reducing an amount of scrap discarded during switching casting types or in an initial
stage of casting, and to a method of the same.
[Background Art]
[0002] Continuous casting and rolling equipment of the related art has been known for having
the same structure as the embodiment of Patent Document 1, that is, a method of providing
a holding furnace between a caster and a rolling line and a method of providing a
coiler or a coiling box between a primary rolling line and a secondary rolling line
in the same manner as Patent Document 2.
[0003] In detail, methods and equipment for performing continuous rolling after continuous
casting, according to steel grades or operation conditions, in the same manner as
Patent Document 1, or performing batch rolling by cutting slabs after continuous casting
in a case in which temperatures at which rolling is possible are not secured, have
been proposed.
[0004] In the case of continuous casting and continuous rolling performed in such a manner
that slabs are connected during processes from casting to rolling, since the speed
of continuous casting is lower than that of rolling, rolling may be performed more
slowly than batch rolling in which rolling and continuous casting are separately performed.
In addition, in a case in which predetermined temperature conditions are not satisfied,
rolling may be difficult. Thus, in the case of continuous casting and continuous rolling,
it is important to set temperatures of slabs to be higher than a specific temperature
in a final rolling stand.
[0005] Thus, even in the case of equipment capable of continuous and batch rolling, when
temperatures of slabs are relatively low in an initial stage of casting, it may be
difficult to perform continuous rolling. Thus, there is a problem in which casting
should be begun with batch rolling.
Patent Document 1: JP 2009-508691 A
Patent Document 2: EP 0841995 A
[Disclosure]
[Technical Problem]
[0006] An aspect of the present disclosure may provide continuous casting and rolling equipment
switching between continuous rolling and batch rolling for improving a percentage
yield of a process by reducing a portion thereof, which is inevitably discarded as
scrap, when casting is switched or in an initial stage of casting.
[Technical Solution]
[0007] According to an aspect of the present disclosure, a method of continuous casting
and rolling, switching continuous rolling and batch rolling, in equipment including
a continuous casting unit, at least two rolling portions, and a coiling box disposed
between the at least two rolling portions comprises performing continuous casting
to produce a slab; primary rolling to reduce a thickness of the slab; cutting to cut
a specific length of the slab from a front end portion thereof in an initial stage
of casting; passing, in which the stab, continuously provided, passes through the
coiling box; and secondary rolling to reduce a thickness of the slab having passed
through the coiling box.
[0008] In this case, in the primary rolling, the thickness of the slab may be reduced using
a rolling reduction rate lower than a normal rolling reduction rate.
[0009] In addition, heating to increase a temperature of the slab passing between the cutting
and the passing may be further performed.
[0010] In an exemplary embodiment, in the heating, the temperature of the slab may be increased
to be higher than a normal raised temperature.
[0011] In an exemplary embodiment, in the heating, the temperature of the slab may be increased
to be higher than the normal raised temperature by 20°C to 50°C.
[0012] In addition, after the primary rolling, measuring a slab temperature to measure the
temperature of the slab is performed, and in the cutting, the slab may be cut based
on the temperature of the slab.
[0013] In the measuring a slab temperature, the temperature of the slab having passed through
a first rolling portion may be measured.
[0014] In an exemplary embodiment, in the cutting, a temperature when the slab passes through
a second rolling portion may be predicted, and the slab may be cut until the temperature
when the slab passes through the second rolling portion is higher than or equal to
a temperature at which rolling is possible.
[0015] In an exemplary embodiment, in the secondary rolling, the slab may be rolled using
a rolling reduction rate higher than the normal rolling reduction rate.
[0016] In an exemplary embodiment, in the primary rolling and the secondary rolling, the
rolling reduction rate may be returned to the normal rolling reduction rate after
a specific period of time, while, in the primary rolling, the rolling reduction rate
may be gradually increased.
[0017] According to an aspect of the present disclosure, equipment switching between continuous
rolling and batch rolling comprises a continuous casting unit; a first rolling portion
and a second rolling portion, disposed in a direction of movement of a slab produced
by the continuous casting unit and rolling the slab; a coiling box disposed between
the first rolling portion and the second rolling portion and configured to allow the
slab having passed through the first rolling portion to be coiled and uncoiled during
batch rolling and to merely pass through the coiling box during continuous rolling;
a cutter disposed between the first rolling portion and the coiling box; a sensor
for measuring a slab temperature disposed on a rear portion of the first rolling portion;
and a control unit connected to the first rolling portion, the second rolling portion,
the coiling box, the cutter, and the sensor for measuring a slab temperature. The
control unit enables the cutter to cut a portion of the slab cast in an initial stage
of casting based on a value measured by the sensor for measuring a slab temperature
during an initial stage of casting. In addition, the control unit enables the coiling
box to allow the slab connected to the continuous casting unit to pass through the
coiling box.
[0018] In this case, a heating portion disposed between the cutter and the coiling box and
increasing a temperature of the slab passing therethrough may be further included.
The control unit may control the heating portion to increase the temperature of the
slab to be higher than a normal raised temperature.
[0019] In an exemplary embodiment, the control unit may maintain a final thickness of the
slab in such a manner that a rolling reduction rate of the first rolling portion is
reduced to be lower than a normal rolling reduction rate, and a rolling reduction
rate of the second rolling portion is increased to be higher than the normal rolling
reduction rate.
[0020] In an exemplary embodiment, the coiling box is configured to have a carousel type
form. When the coiling box allows the slab to pass therethrough, a mandrel of the
coiling box may be disposed above the slab passing therethrough.
[0021] In an exemplary embodiment, the heating portion may include an inductive heater having
an open side surface. The inductive heater may be configured to enter and be removed
in a lateral direction of the slab.
[0022] In addition, in an exemplary embodiment, a pusher and a piler, disposed between the
heating portion and the cutter and removing a slab having been cut from a path of
the slab, may be further included.
[Advantageous Effects]
[0023] According to an aspect of the present disclosure, continuous casting and rolling
equipment switching between continuous rolling and batch rolling for improving a percentage
yield of a process by reducing a portion thereof, which is inevitably discarded as
scrap, when casting is switched or in an initial stage of casting, may be provided.
[Description of Drawings]
[0024]
FIG. 1 is a view illustrating batch rolling in an exemplary embodiment in the present
disclosure.
FIG. 2 is a view illustrating continuous rolling in an exemplary embodiment.
[Best Mode for Invention]
[0025] Hereinafter, exemplary embodiments in the present disclosure will be described in
detail with reference to the attached drawings.
[0026] FIGS. 1 and 2 illustrate an exemplary embodiment in the present disclosure. FIG.
1 illustrates continuous casting and rolling equipment switching between continuous
rolling and batch rolling of an exemplary embodiment, performing batch rolling. FIG.
2 illustrates continuous casting and rolling equipment switching between continuous
rolling and batch rolling, performing continuous rolling.
[0027] As illustrated in FIG. 1, the continuous casting and rolling equipment switching
between continuous rolling and batch rolling of an exemplary embodiment includes a
continuous casting unit 10; a first rolling portion 20 disposed in a direction of
movement of a slab produced by the continuous casting unit 10 and rolling the slab;
temperature measuring sensors 110, 111, 112, 113, and 114, measuring a temperature
of the slab having passed through the first rolling portion 20; cutters 30 and 40
cutting the slab having passed through the first rolling portion 20; a heating portion
50 heating a slab not having been cut; a coiling box 60 configured in such a manner
that the slab having passed through the first rolling portion 20 and the heating portion
50 is coiled and uncoiled during batch rolling and passes through the coiling box
60 during continuous rolling; a second rolling portion 70 disposed to be contiguous
with the coiling box 60; a run out table 80 cooling a slab having become a strip after
rolling is finished; a cutter 90 cutting the slab corresponding to an amount of a
single coil; a coiler 100; and a control unit 120 connected to the first rolling portion
20, the second rolling portion 70, the coiling box 60, the cutters 30, 40, and 90,
and the temperature measuring sensors 110, 111, 112, 113, and 114.
[0028] In an exemplary embodiment, the continuous casting portion 10 may adopt any composition
that may perform continuous casting. In the exemplary embodiment, the continuous casting
portion 10 cools the slab in such a manner that a plurality of segments, (not illustrated),
are disposed below a mold.
[0029] The first rolling portion 20 is disposed to be contiguous with the continuous casting
portion 10 and applies rolling force to the slab having passed through the continuous
casting portion 10, thereby rolling the slab to have a target thickness. An exemplary
embodiment of FIGS. 1 and 2 illustrates a rolling portion including three stands,
but the number of stands may be increased or reduced according to need. The first
rolling portion 20 is connected to the control unit 120 and may control a rolling
reduction rate depending on a signal of the control unit 120.
[0030] A temperature measuring sensor 110 is disposed on a rear end portion of the first
rolling portion 20 and measures a temperature of a slab of which first rolling is
finished. The temperature measuring sensor 110 may be configured to be either a contact
type or a non-contact type. The temperature measuring sensor 110 may be disposed in
a plurality of positions, such as on the rear end portion of the first rolling portion
20, as well as on front and rear end portions of the heating portion 50 and the second
rolling portion 70 and on a rear end portion of the continuous casting portion 10,
in order to detect a temperature of the slab passing therethrough.
[0031] The cutters 30, 40, and 90 are provided as three cutters in an exemplary embodiment.
Two cutters are disposed on the rear end portion of the first rolling portion 20,
while a cutter is disposed on a front end portion of the coiler 100. In the case of
a cutter 30 disposed on the rear end portion of the first rolling portion 20, a plurality
of cutters are disposed depending on a thickness of the slab. However, only a single
cutter may be used.
[0032] The heating portion 50 is configured using an inductive heater having an open side
surface in an exemplary embodiment. In other words, the heating portion 50 is configured
to have a '

' shape overall when taken from the front thereof, since a side surface thereof is
open. The inductive heater may be connected to a means of movement to be able to enter
and be removed in a lateral direction of the slab. The inductive heater may deviate
from a path of the slab when heating is unnecessary.
[0033] In addition, temperature measuring sensors 111 and 112 may be disposed on the front
and rear end portion of the heating portion 50. Thus, the control unit 120 may control
the heating portion 50 to increase a temperature of the slab to a desired temperature.
[0034] In the meantime, although not illustrated in FIGS. 1 and 2, a pusher and piler (not
illustrated) may be disposed in a space between the cutters 30 and 40 and the heating
portion 50. The pusher and the piler push the slab cut by the cutters 30 and 40 out
to remove the slab cut by the cutters from a path of the slab. A cut slab removal
device in addition to the pusher and the piler may also be used.
[0035] In an exemplary embodiment, the coiling box 60 may include two mandrels 61 and 62.
The two mandrels 61 and 62 may be configured to have a carousel type form having a
structure in which the two mandrels 61 and 62 rotate around a circular track, and
coiling and uncoiling are alternately performed. In addition, in a case in which continuous
rolling is performed as illustrated in FIG. 2, in order not to block the path of the
slab, the coiling box 60 may be disposed in a higher position so that a plurality
of mandrels may be disposed above the slab passing therethrough, but the present disclosure
is not limited thereto. In detail, the coiling box 60 may have a structure in which
the slab passes between the mandrels 61 and 62.
[0036] The second rolling portion 70 is disposed to be contiguous with the coiling box 60.
In the exemplary embodiment, the second rolling portion 70 includes five rolling stands.
However, the second rolling portion 70 is not limited thereto, but may include a plurality
of rolling stands. In addition, rolling stands may be disposed contiguously, and may
be disposed to be spaced apart from each other.
[0037] The second rolling portion 70 rolls the slab, a thickness of which has been reduced
by passing through the first rolling portion 20, using the plurality of rolling stands
and applies rolling force to the slab, so that a thickness thereof may be reduced
to a final target thickness. In this case, the control unit 120 may manage a temperature
of the second rolling portion 70 to be a temperature at which rolling is possible,
using temperature measuring sensors 113 and 114 disposed on the front and rear end
portion of the second rolling portion 70.
[0038] The run out table 80 has a structure in which the slab, having become a strip, is
cooled using a cooling water supplying device disposed thereabove by allowing the
slab to pass through a specific section above a roller. In the case of continuous
rolling, the cutter 90 cuts the slab having passed through the run out table 80 to
be an amount of a single coil before the strip is wound around the coiler 100.
[0039] The control unit 120 is connected to each device and may control a different device
based on information of each device. In detail, in an exemplary embodiment, the control
unit 120 is connected to at least the first rolling portion 20, the cutters 30 and
40, the heating portion 50, the coiling box 60, the second rolling portion 70, and
the temperature measuring sensor 110 and controls the first rolling portion 20, the
cutters 30 and 40, the heating portion 50, the coiling box 60, and the second rolling
portion 70 based on a temperature value of the temperature measuring sensor 110.
[0040] In the case of a structure described above, if casting is begun with continuous rolling
in an initial stage of casting, it is impossible to secure the temperature at which
rolling is possible before a portion of the slab, a temperature of which is relatively
low in the initial stage of casting, passes through the last stand of the second rolling
portion 70. In addition, in the case of the structure of the exemplary embodiment,
when batch rolling is converted into continuous rolling, mandrels 61 and 62 should
be moved in the coiling box 60, so that the time to unwind a coil having been previously
wound may be required. Thus, a slab continuously cast while the coil is being unwound
should be cut using the cutters 30 and 40 to be discarded as scrap. In a case in which
the slab cast while the coil is being unwound is discarded as scrap, the slab weighing
10 tons or more is discarded as scrap, thereby significantly affecting a percentage
yield.
[0041] Thus, the continuous casting and rolling equipment switching between continuous rolling
and batch rolling of an exemplary embodiment begins casting with continuous rolling
allowing the slab to pass through a coiling box merely in the initial stage of casting,
using the control unit 120, while a specific length of a front end portion of the
slab is cut. In this case, a cutting length may be controlled by the control unit
120 so that a temperature of the slab before passing through the last stand of the
second rolling portion 70 may be a temperature at which rolling is possible.
[0042] In addition, in order to reduce the cutting length, in an exemplary embodiment, when
the heating portion 50 is in a normal state, the slab is heated so that a temperature
thereof may be higher than a heating rate, thereby compensating for a relatively low
temperature in the initial stage. In this case, the normal state refers to a time
at which casting is stable.
[0043] In other words, when a temperature of the slab is relatively low in the initial stage
of casting, a quantity of heat greater than a heating amount provided in the middle
of casting is provided. In this case, a temperature increasing a temperature of the
slab by the heating amount is increased to a temperature higher than a normal state
by 20°C to 50°C, so that a temperature of the second rolling portion 70 may be secured
in the initial stage. In a case in which a difference in raised temperatures is less
than 20°C, an effect caused by additional heating is insignificant. In a case in which
a difference in heat rates is greater than 50°C, a quality of the slab may be affected.
In addition, peripheral equipment of the heating portion 50 may be degraded, and a
reduction in lifespan thereof may be affected.
[0044] In addition, the control unit 120 may improve plastic energy dissipation of the slab
in the second rolling portion 70 to secure the temperature of the second rolling portion
70 in such a manner that a rolling reduction rate of the first rolling portion 20
is reduced to be lower than that in a normal state in the initial stage of casting,
and a rolling reduction rate of the second rolling portion 70 is increased to be higher
than that in the normal state.
[0045] In detail, in the case of the heating portion 50, when a thickness of the slab is
relatively thick, heating efficiency may be improved. Thus, the rolling reduction
rate of the first rolling portion 20 may be reduced to be lower than that in the normal
state, thereby improving efficiency of the heating portion 50 to increase a heating
amount provided to the slab.
[0046] In case of the first rolling portion 20 and the second rolling portion 70, in the
normal state, maximum rolling force is not used, but a certain margin is retained
in case that there is a problem, such as equipment trouble, during a process. However,
in the initial stage of casting, the control unit 120 reduces the rolling reduction
rate of the first rolling portion 20 using a marginal rolling reduction rate of the
second rolling portion 70 and increases the rolling reduction rate of the second rolling
portion 70 to cover a relatively low temperature of the slab in the initial stage
using plastic energy dissipation of the second rolling portion 70.
[0047] In the meantime, in a case in which a temperature of the slab is secured after the
slab has passed through the coiler 100 in the initial stage, the control unit 120
controls an entirety of the first rolling portion 20 and the second rolling portion
70 to have a marginal rolling reduction rate in such a manner that the rolling reduction
rate of the first rolling portion 20 is increased to be that in the normal state and
the rolling reduction rate of the second rolling portion 70 is reduced to be that
in the normal state. In this case, rolling reduction rates of the first rolling portion
20 and the second rolling portion 70 may gradually be changed.
[0048] However, even though a rolling reduction rate and the heating portion 50 are controlled
as described above, in a certain section in the initial stage of casting, a temperature
at which rolling is possible may not be secured in the second rolling portion 70.
Thus, the control unit 120 measures a temperature of the slab having passed through
the first rolling portion 20 using the temperature measuring sensor 110 disposed on
an exit side of the first rolling portion 20. The control unit 120 predicts a temperature
of the slab when the slab passes through the second rolling portion 70 in consideration
of a measured temperature, a heating amount that the heating portion 50 may provide,
and a heating amount lost from the slab while the slab is passing through the heating
portion 50, the coiling box 60, and the second rolling portion 70. In a case in which
the temperature of the slab is lower than the temperature at which rolling is possible,
the section of the slab, the temperature of which is relatively low, is cut by the
cutters 30 and 40.
[0049] In the meantime, the control unit 120 may control to prevent a collision occurring
when the slab enters the first rolling portion 20 in such a manner that the first
rolling portion 20 applies rolling force thereto after a front end portion of the
slab passes through the first rolling portion 20 in the initial stage.
[0050] A method of operating the continuous casting and rolling equipment switching between
continuous rolling and batch rolling described above will be described.
[0051] In order to begin casting with continuous rolling in the initial stage of casting,
as illustrated in FIG. 2, the coiling box 60 begins casting with the mandrels 61 and
62 moved above the path of the slab.
[0052] After a continuous casting operation to continuously cast the slab in a continuous
casting portion, in order to prevent a problem related to the slab entering the first
rolling portion 20 in the initial stage of casting, a primary rolling operation in
which the first rolling portion 20 begins to apply roll force thereto after the front
end portion of the slab passes therethrough is performed. In this case, a temperature
measuring operation to measure a temperature of the slab having passed through the
first rolling portion 20 using the temperature measuring sensor 110 is performed.
Based on a measured temperature, a temperature when the slab passes through the second
rolling portion 70 is predicted. In a case in which the temperature is lower than
the temperature at which rolling is possible, a cutting operation to cut the slab
using the cutters 30 and 40 is performed. In the cutting operation, it is possible
to cut the slab uniformly at a length obtained based on experience without the temperature
measuring operation. However, based on a temperature value in the temperature measuring
operation, the cutting length may be reduced, thereby improving a percentage yield.
[0053] A slab having been cut is removed from the path of the slab. In the case of a slab
not having been cut and connected to the continuous casting portion 10, a heating
operation to raise a temperature of the slab using the heating portion 50 is performed.
In order to provide a larger quantity of heat by improving efficiency of a temperature
rise and to raise a temperature on a rear end portion of the slab by plastic energy
dissipation, in the first rolling portion 20, rolling reduction is performed using
a rolling reduction rate lower than that in the normal state in the primary rolling
operation. Insufficient rolling reduction in the first rolling portion 20 is compensated
for in such a manner that rolling reduction greater than that in the normal state
in the second rolling portion 70 is performed in a secondary rolling operation to
be subsequently described.
[0054] After the heating operation, a passing operation in which the slab merely passes
through the coiling box 60. Subsequently, the secondary rolling operation is performed
by the second rolling portion 70. In the secondary rolling operation as described
above, rolling reduction is performed to the slab using a rolling reduction rate higher
than that in the normal state, while a portion thereof in which rolling reduction
is not performed in the primary rolling operation is compensated for.
[0055] According to a method of an exemplary embodiment, a coiling box is controlled so
that continuous rolling may be performed in the initial stage of casting, and a portion
of the slab in which continuous rolling may not be performed is cut, thereby reducing
an amount of scrap generated during a switch between continuous rolling and batch
rolling or in the initial stage of casting. Thus, a percentage yield may be improved.
[0056] In addition, the heating amount is increased and plastic energy dissipation is used
to reduce a portion of the slab in which continuous rolling may not be performed,
thereby generating scrap only about 20% to 30% of scrap generated when batch rolling
is switched to continuous rolling. Thus, the switch between batch rolling and continuous
rolling is possible, thereby greatly contributing to improving a percentage yield.
Exemplary Example
[0057] Table 1 below is a contrast table contrasting a case in which rolling in the initial
stage is performed on condition of continuous casting and rolling equipment switching
between continuous rolling and batch rolling in a normal state and a case in which
rolling is performed using a method of the present disclosure.
[0058] A rolling reduction rate of a first rolling portion was reduced to be lower than
that in the normal state, and a rolling reduction rate of a second rolling portion
was increased, so that an entirety of rolling reduction rates were equal, and a degree
of temperature rise of a heating portion was increased to be higher than that in the
normal state by 45°C. As a result, there was a temperature difference of about 20°C
between a temperature on an exit side of the second rolling portion 70 in the initial
stage and a temperature in the normal state. Thus, an amount of discarded scrap was
significantly reduced, thereby improving a percentage yield.
[Table 1]
| Item |
Comparative Example (Normal State) |
Exemplary Example |
| Rolling Reduction Rate of First Rolling Portion |
60% |
55% |
| Degree of Temperature Rise of Heating Portion |
100°C |
145°C |
| Rolling Reduction Rate of Second Rolling Portion |
80% |
82% |
| Temperature on Exit Side of Second Rolling Portion in Initial Stage |
About 780°C |
About 800°C |
| Amount of Scrap |
15 tons |
5 tons |
[0059] In a case in which a certain degree of casting in the initial stage and rolling is
performed, for example, about four coils are produced, and a stable temperature on
the exit side thereof is secured, a slab is returned to the normal state so that each
component of the continuous casting and rolling equipment switching between continuous
rolling and batch rolling may have a marginal operation range.
[0060] While exemplary embodiments have been shown and described above, it will be apparent
to those skilled in the art that modifications and variations could be made without
departing from the scope of the present invention as defined by the appended claims.
1. A method of continuous casting and rolling, switching continuous rolling and batch
rolling, in equipment including a continuous casting unit, at least two rolling portions,
and a coiling box disposed between the at least two rolling portions, the method comprising:
performing continuous casting to produce a slab;
primary rolling to reduce a thickness of the slab;
cutting to cut a specific length of the slab from a front end portion of the slab
in an initial stage of casting;
passing, in which the slab, continuously provided, passes through the coiling box;
and
secondary rolling to reduce a thickness of the slab having passed through the coiling
box.
2. The method of claim 1, wherein in the primary rolling, the thickness of the slab is
reduced using a rolling reduction rate lower than a rolling reduction rate in normal
condition.
3. The method of claim 2, further comprising heating, to increase a temperature of the
slab, between the cutting and the passing.
4. The method of claim 3, wherein in the heating, the temperature of the slab is increased
to be higher than a raised temperature in normal condition.
5. The method of claim 4, wherein in the heating, the temperature of the slab is increased
to be higher than the raised temperature in normal condition by 20°C to 50°C.
6. The method of claim 2, wherein after the primary rolling, measuring a slab temperature
to measure the temperature of the slab is performed, and in the cutting, the slab
is cut based on the temperature of the slab.
7. The method of claim 6, wherein in the measuring a slab temperature, the temperature
of the slab having passed through a first rolling portion is measured.
8. The method of claim 7, wherein in the cutting, a temperature when the slab passes
through a second rolling portion is predicted, and the slab is cut until the temperature
when the slab passes through the second rolling portion is higher than or equal to
a temperature at which rolling is possible.
9. The method of claim 6, wherein in the secondary rolling, the slab is rolled using
a rolling reduction rate higher than the rolling reduction rate in normal condition.
10. The method of claim 9, wherein in the primary rolling and the secondary rolling, the
rolling reduction rate is returned to the rolling reduction rate in normal condition
after a specific period of time.
11. The method of claim 2, wherein in the primary rolling, the rolling reduction rate
is gradually increased.
12. Continuous casting and rolling equipment switching between continuous rolling and
batch rolling, comprising:
a continuous casting unit;
a first rolling portion and a second rolling portion, disposed in a direction of movement
of a slab produced by the continuous casting unit and rolling the slab;
a coiling box disposed between the first rolling portion and the second rolling portion
and configured to allow the slab having passed through the first rolling portion to
be coiled and uncoiled during batch rolling and to merely pass through the coiling
box during continuous rolling;
a cutter disposed between the first rolling portion and the coiling box;
a sensor for measuring a slab temperature disposed on a rear portion of the first
rolling portion; and
a control unit connected to the first rolling portion, the second rolling portion,
the coiling box, the cutter, and the sensor for measuring a slab temperature,
wherein the control unit enables the cutter to cut a portion of the slab cast in an
initial stage of casting based on a value measured by the sensor for measuring a slab
temperature during an initial stage of casting and enables the coiling box to allow
the slab connected to the continuous casting unit to pass through the coiling box.
13. The continuous casting and rolling equipment switching between continuous rolling
and batch rolling of claim 12, further comprising a heating portion disposed between
the cutter and the coiling box and increasing a temperature of the slab passing through
the heating portion,
wherein the control unit controls the heating portion to increase the temperature
of the slab to be higher than a raised temperature in normal condition.
14. The continuous casting and rolling equipment switching between continuous rolling
and batch rolling of claim 13, wherein the control unit maintains a final thickness
of the slab in such a manner that a rolling reduction rate of the first rolling portion
is reduced to be lower than a rolling reduction rate in normal condition, and a rolling
reduction rate of the second rolling portion is increased to be higher than the rolling
reduction rate in normal condition.
15. The continuous casting and rolling equipment switching between continuous rolling
and batch rolling of claim 12, wherein the coiling box is configured to have a carousel
type form including a plurality of mandrels, and when the coiling box allows the slab
to pass through the coiling box, a mandrel of the coiling box is disposed above the
slab passing through the coiling box.
16. The continuous casting and rolling equipment switching between continuous rolling
and batch rolling of claim 13, wherein the heating portion includes an inductive heater
having an open side surface, and the inductive heater is configured to enter and be
removed in a lateral direction of the slab.
17. The continuous casting and rolling equipment switching between continuous rolling
and batch rolling of claim 13, further comprising a pusher and a piler, disposed between
the heating portion and the cutter and removing a slab having been cut from a path
of the slab.