U.S. patent application number 16/759046 was filed with the patent office on 2020-10-22 for continuous casting and rolling apparatus and continuous casting and rolling method.
The applicant listed for this patent is POSCO. Invention is credited to Kyung-Se CHA, Yong-Seok CHO, Jea-Sook CHUNG, Jong-Pan KONG.
Application Number | 20200331045 16/759046 |
Document ID | / |
Family ID | 1000004945032 |
Filed Date | 2020-10-22 |
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United States Patent
Application |
20200331045 |
Kind Code |
A1 |
CHUNG; Jea-Sook ; et
al. |
October 22, 2020 |
CONTINUOUS CASTING AND ROLLING APPARATUS AND CONTINUOUS CASTING AND
ROLLING METHOD
Abstract
A continuous casting and rolling apparatus includes: a
continuous casting device; a cutting device that is disposed at the
output side of the continuous casting device and cuts an inner slab
produced from the continuous casting device; a rolling device
pressing down on the slab and disposed downstream of the continuous
casting device in the moving direction of the inner slab; a tunnel
furnace which is disposed between the cutting device and the
rolling device and heats the slab disposed on the main path of the
inner slab that is transferred from the continuous casting device
to the rolling device; and a loading adjustment unit which is
disposed adjacent to the tunnel furnace and unloads the slab from
the main path from the outlet side of the tunnel furnace and loads
the slab onto the main path from the inlet side of the tunnel
furnace.
Inventors: |
CHUNG; Jea-Sook;
(Gwangyang-si, KR) ; CHO; Yong-Seok;
(Gwangyang-si, KR) ; KONG; Jong-Pan;
(Gwangyang-si, KR) ; CHA; Kyung-Se; (Gwangyang-si,
KR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
POSCO |
Pohang-si |
|
KR |
|
|
Family ID: |
1000004945032 |
Appl. No.: |
16/759046 |
Filed: |
November 2, 2018 |
PCT Filed: |
November 2, 2018 |
PCT NO: |
PCT/KR2018/013277 |
371 Date: |
April 24, 2020 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21B 39/02 20130101;
B22D 11/126 20130101; B21B 15/0007 20130101; B22D 11/1213 20130101;
B21B 45/004 20130101; B21B 1/466 20130101 |
International
Class: |
B21B 1/46 20060101
B21B001/46; B22D 11/126 20060101 B22D011/126; B22D 11/12 20060101
B22D011/12; B21B 15/00 20060101 B21B015/00; B21B 39/02 20060101
B21B039/02; B21B 45/00 20060101 B21B045/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 3, 2017 |
KR |
10-2017-0145823 |
Claims
1. A continuous casting and rolling apparatus, comprising: a
continuous casting device; a cutting device disposed on an outlet
side of the continuous casting device and cutting an inner slab
produced in the continuous casting device; a rolling device
pressing a slab down and disposed downstream of the continuous
casting device in a moving direction of the inner slab; a tunnel
furnace provided between the cutting device and the rolling device
and heating a slab located on a main path of the inner slab
transferred from the continuous casting device to the rolling
device; and a loading adjustment unit provided adjacent to the
tunnel furnace, separating the slab on the main path from the
tunnel furnace and introducing the slab onto the main path from an
inlet side of the tunnel furnace.
2. The continuous casting and rolling apparatus of claim 1, wherein
the loading adjustment unit comprises: a drawing device provided
adjacent to an outlet side of the tunnel furnace and separating the
slab from the main path to be introduced onto a supplementary path;
and an introducing device provided adjacent to the inlet side of
the tunnel furnace and receiving the slab through the supplementary
path to be introduced onto the main path.
3. The continuous casting and rolling apparatus of claim 2, wherein
the loading adjustment unit is configured to introduce the inner
slab, separated from the main path of the outlet side of the tunnel
furnace by the drawing device, onto a main path of the inlet side
of the tunnel furnace by the introducing device.
4. The continuous casting and rolling apparatus of claim 2, wherein
the apparatus comprises a reheating device on the supplementary
path between the introducing device and the drawing device and
heating the slab on the supplementary path.
5. The continuous casting and rolling apparatus of claim 2, wherein
the apparatus comprises a scarfing device provided on the
supplementary path between the introducing device and the drawing
device and heating the slab on the supplementary path.
6. The continuous casting and rolling apparatus of claim 2, wherein
the introducing device is configured to receive at least one of an
inner slab produced in the continuous casting device and an outer
slab transferred from the outside and introduce the same onto the
main path.
7. A continuous casting and rolling method, comprising: a process
of supplying an inner slab, involving cutting an inner slab
produced in a continuous casting device and supplying the same to a
tunnel furnace; a rolling process involving pressing down the slab
received from a main path of the slab moving through the tunnel
furnace; and a subworking process performed between the inner slab
supply process and the rolling process and involving separating the
slab on the main path from an outlet side of the tunnel furnace
when the rolling process stops and introducing the slab onto the
main path from an inlet side of the tunnel furnace when the rolling
process resumes.
8. The continuous casting and rolling method of claim 7, wherein
the subworking comprises: a drawing process involving separating
the slab on the main path from the outlet side of the tunnel
furnace when the rolling process stops; and an introducing process
involving receiving the slab separated from the main path of the
outlet side of the tunnel furnace and introducing the same onto the
main path of the inlet side of the tunnel furnace when the rolling
process resumes.
9. The continuous casting and rolling method of claim 8, wherein
the subworking process involves the introducing process subsequent
to the drawing process so as to exclude intervention of another
step therebetween, when the slab introduced onto the main path
maintains a temperature for rolling.
10. The continuous casting and rolling method of claim 8, wherein
the subworking process further comprises reheating performed before
the introducing process and involving heating the slab introduced
onto the main path during the subworking on the supplementary path
when the slab has a temperature below the temperature for
rolling.
11. The continuous casting and rolling method of claim 8, wherein
the subworking process further comprises a scarfing process
performed before the introducing process and involving scarfing the
slab separated from the main path of the outlet side of the tunnel
furnace on the supplementary path through which the slab is
delivered to be introduced onto the main path of the inlet side of
the tunnel furnace.
12. The continuous casting and rolling method of claim 8, wherein
the subworking process further comprises a process of supplying an
outer slab, performed before the introducing process and involving
introducing the outer slab produced outside onto the supplementary
path through which the slab separated from the main path of the
outlet side of the tunnel furnace is delivered to be introduced
onto the main path of the inlet side of the tunnel furnace.
13. The continuous casting and rolling method of claim 12, wherein
the process of supplying an outer slab is performed when capacity
of the slab performing pressing down during the rolling process is
larger than a supply amount of the inner slab.
Description
TECHNICAL FIELD
[0001] The present invention relates to a continuous casting and
rolling apparatus and a continuous casting and rolling method.
BACKGROUND ART
[0002] In a mini mill process, a layout is configured to directly
roll a cut slab produced through a continuous casting process
without cooling.
[0003] A tunnel furnace is installed as a space functioning as a
buffer between a continuous casting device and a rolling
device.
[0004] This tunnel furnace serves as a space for connecting two
continuous casting devices and a single rolling device and as a
buffer space when a certain amount of time is required for rolling
mill replacement. In order to compensate for a temperature drop
while a slab remains in the space, a heater having a gas heating
method or an inducted heating method is installed to compensate for
the temperature drop.
[0005] In the mini mill process, however, the slab produced in the
continuous casting device is promptly transferred to the rolling
device to be rolled, thereby causing a problem that an actual yield
is significantly reduced because the slab in the tunnel furnace and
that newly produced in the continuous casting device are scrapped
when an abnormal operation of the rolling device occurs for a long
period of time. That is, the conventional mini mill process is
advantageous in terms of energy in that it employs the continuous
casting device and the rolling device directly connected to each
other according to a flow of a material but is disadvantageous in
that its ability to cope with abnormal operations is inferior.
[0006] Further, an exterior material of a vehicle or a product
required to meet stringent surface quality requirements is subject
to a scarfing process after produced using a cut slab, which
removes a surface defect generated during the continuous casting.
To apply the scarfing to the mini mill process, however, a scarfing
device needs to be installed online in consideration of the
characteristics of the mini mill process, that is, the slab
produced in the continuous casting device is promptly transferred
to the rolling device. In this case, it may be disadvantageous in
that the slabs, not subject to scarfing but in a region in which a
scarfing device is installed, are cooled when scarfing is performed
for selective slabs.
[0007] In addition, there may be a problem that the continuous
casting device may not operate in the mini mill process, or rolling
capacity of the rolling device may be wasted according to a slab
production speed of the continuous casting device.
[0008] Accordingly, research into a continuous casting and rolling
apparatus and a continuous casting and rolling method is required
to solve the above issues.
DISCLOSURE
Technical Problem
[0009] An object of the present disclosure is to provide a
continuous casting and rolling apparatus for preventing a problem
of a reduced actual yield of a slab while compensating for a
temperature drop of the slab during an abnormal operation, and a
continuous casting and rolling method.
[0010] Another object of the present invention is to provide a
continuous casting and rolling apparatus for scarfing a slab during
the continuous casting or preventing a problem of wasted capacity
of a rolling device, and a continuous casting and rolling
method.
Technical Solution
[0011] According to an aspect of the present disclosure, a
continuous casting and rolling apparatus may include a continuous
casting device; a cutting device disposed on an outlet side of the
continuous casting device and cutting an inner slab produced in the
continuous casting device; a rolling device pressing a slab down
and disposed downstream of the continuous casting device in a
moving direction of the inner slab; a tunnel furnace provided
between the cutting device and the rolling device and heating a
slab located on a main path of the inner slab transferred from the
continuous casting device to the rolling device; and a loading
adjustment unit provided adjacent to the tunnel furnace, separating
the slab on the main path from the tunnel furnace and introducing
the slab onto the main path from an inlet side of the tunnel
furnace.
[0012] The loading adjustment unit may include a drawing device
provided adjacent to an outlet side of the tunnel furnace and
separating the slab from the main path to be introduced onto a
supplementary path; and an introducing device provided adjacent to
the inlet side of the tunnel furnace and receiving the slab through
the supplementary path to be introduced onto the main path
[0013] Further, the loading adjustment unit may introduce the inner
slab, separated from the main path of the outlet side of the tunnel
furnace by the drawing device, onto a main path of the inlet side
of the tunnel furnace by the introducing device.
[0014] The continuous casting and rolling apparatus may further
include a reheating device on the supplementary path between the
introducing device and the drawing device and heating the slab on
the supplementary path.
[0015] The continuous casting and rolling apparatus may further
include a scarfing device provided on the supplementary path
between the introducing device and the drawing device and heating
the slab on the supplementary path.
[0016] The introducing device may receive at least one of an inner
slab produced in the continuous casting device and an outer slab
transferred from the outside and introduce the same onto the main
path.
[0017] A continuous casting and rolling method may include a
process of supplying an inner slab, involving cutting an inner slab
produced in a continuous casting device and supplying the same to a
tunnel furnace; a rolling process involving pressing down the slab
received from a main path of the slab moving through the tunnel
furnace; and a subworking process performed between the process of
supplying an inner slab and the rolling process and involving
separating the slab on the main path from an outlet side of the
tunnel furnace when the rolling process stops and introducing the
slab onto the main path from an inlet side of the tunnel furnace
when the rolling process resumes.
[0018] The subworking process may include a drawing process
involving separating the slab on the main path from the outlet side
of the tunnel furnace when the rolling process stops; and an
introducing process involving receiving the slab separated from the
main path of the outlet side of the tunnel furnace and introducing
the same onto the main path of the inlet side of the tunnel furnace
when the rolling process resumes.
[0019] The subworking process may include the introducing process
subsequent to the drawing process so as to exclude intervention of
another process therebetween, when the slab introduced onto the
main path maintains a temperature for rolling.
[0020] The subworking process may further include a reheating
process performed before the introducing process and involving
heating the slab introduced onto the main path during the
subworking process on the supplementary path when the slab has a
temperature below the temperature for rolling.
[0021] The subworking process may further include a scarfing
process performed before the introducing process and involving
scarfing the slab separated from the main path of the outlet side
of the tunnel furnace on the supplementary path through which the
slab is delivered to be introduced onto the main path of the inlet
side of the tunnel furnace.
[0022] The subworking process may further include a process of
supplying an outer slab, performed before the introducing process
and involving introducing the outer slab produced outside onto the
supplementary path through which the slab separated from the main
path of the outlet side of the tunnel furnace is delivered to be
introduced onto the main path of the inlet side of the tunnel
furnace.
[0023] The outer slab supply may be performed when capacity of the
slab performing pressing down during the rolling process is larger
than a supply amount of the inner slab.
Advantageous Effects
[0024] The continuous casting and rolling apparatus and the
continuous casting and rolling method of the present invention are
advantageous in that a problem of a reduced actual yield of a slab
can be prevented while a temperature drop of the slab can be
compensated during an abnormal operation.
[0025] In another aspect, the continuous casting and rolling
apparatus and the continuous casting and rolling method are
advantageous in that scarfing can be performed for a slab during
the continuous casting or a problem of wasted capacity of a rolling
device can be prevented.
DESCRIPTION OF DRAWINGS
[0026] FIG. 1 is a layout diagram illustrating a moving path of a
slab in the continuous casting and rolling apparatus of the present
invention during an abnormal operation.
[0027] FIG. 2 is a layout diagram illustrating a moving path of a
slab compensating for a temperature loss in the continuous casting
and rolling apparatus during an abnormal operation.
[0028] FIG. 3 is a layout diagram illustrating a moving path for
scarfing of a slab in the continuous casting and rolling
apparatus.
[0029] FIG. 4 is a layout diagram illustrating a moving path for
receiving an outer slab in the continuous casting and rolling
apparatus.
[0030] FIG. 5 is a layout diagram illustrating a moving path for
receiving an outer slab and performing scarfing in the continuous
casting and rolling apparatus.
[0031] FIG. 6 is a diagram illustrating an order of the continuous
casting and rolling method of the present invention.
[0032] FIG. 7 is a diagram illustrating a subworking process during
the continuous casting and rolling method.
BEST MODE FOR INVENTION
[0033] Hereinafter, exemplary embodiments of the present invention
will be described in detail with reference to the accompanying
drawings. Meanwhile, the spirit of the present invention is not
limited to the suggested embodiments, and those skilled in the art
to which the present invention pertains could easily suggest
another embodiment which falls within the spirit of the present
invention through the addition, modification, and deletion of
another component without departing from the spirit of the present
invention.
[0034] In the following description, components having the same
function within the same scope illustrated in the drawings of the
embodiments are illustrated by using the same reference
numerals.
[0035] The present invention relates to a continuous casting and
rolling apparatus and a continuous casting and rolling method. In
the present invention, a problem of a reduced actual yield of a
slab can be prevented, and scarfing can be performed on a slab
during the continuous casting. A problem of wasted capacity of a
rolling device 30 can be prevented.
[0036] Specifically, with reference to the accompanying drawings,
FIG. 1 is a layout diagram illustrating a moving path of a slab in
the continuous casting and rolling apparatus of the present
invention during an abnormal operation. Based on FIG. 1, a
continuous casting and rolling apparatus according to an exemplary
embodiment may include a continuous casting device 10; a cutting
device 20 disposed on an outlet side of the continuous casting
device 10 and cutting an inner slab IS produced in the continuous
casting device 10; a rolling device 30 pressing a slab down and
disposed downstream of the continuous casting device 10 in a moving
direction of the inner slab IS; a tunnel furnace 40 provided
between the cutting device 20 and the rolling device 30 and heating
a slab located on a main path MP of the inner slab IS transferred
from the continuous casting device 10 to the rolling device 30; and
a loading adjustment unit 50 provided adjacent to the tunnel
furnace 40, separating the slab on the main path MP from the tunnel
furnace 40 and introducing the slab onto the main path MP from an
inlet side of the tunnel furnace 40.
[0037] According to such configuration, the problem of a reduced
actual yield, which may be caused by a defect of the rolling device
30 or a scrapped slab during an abnormal operation in which a
rolling operation such as a replacement of a transfer roll is
impractical, may be prevented.
[0038] In other words, the slab located in the tunnel furnace 40 or
that produced by molten steel remaining in the continuous casting
device 10 is separated from a main path MP of an outlet side of the
tunnel furnace 40 by the loading adjustment unit 50 during the
abnormal operation and introduced onto a supplementary path SP. The
slab on the supplementary path SP is reintroduced onto the main
path MP of an inlet side of the tunnel furnace 40, thereby
increasing a time for which the slab is positioned on a moving
path.
[0039] By securing a bypass, on which the slab remains without
entering the rolling device 30, the slab can be prevented from
being wasted by the scrap treatment due to insecurity of the path
on which the slab remains.
[0040] Besides, the loading adjustment unit 50 introduces the slab
introduced onto the main path MP onto an inlet side of the tunnel
furnace 40, thereby compensating for a temperature of the slab
lowered during its transfer through the supplementary path SP by a
temperature at which the rolling can be performed.
[0041] The continuous casting device 10 may serve to produce an
inner slab IS from the molten steel through a casting process. That
is, the continuous casting device 10 supplies the molten steel to a
mold in a tundish, and the supplied molten steel forms a cast while
depriving heat. The inner slab IS is guided by a segment roll and a
pinch roll and may be moved and supplied to the rolling device 30
to be described later.
[0042] Such continuous casting device 10, however, produces the
internal cast steel IS depending on a solidification speed of the
molten steel, it is difficult to control a production speed.
Accordingly, production of a product by continuously receiving the
inner slabs IS produced in the continuous casting device 10 and
pressing down the same using the rolling device 30 has a limitation
of a speed.
[0043] However, the inner slab released from the continuous casting
device 10 has a high average temperature, it is advantageous in
that a temperature required during the rolling operation can be
guaranteed.
[0044] The cutting device 20 can serve to control whether a slab
(inner slab IS or outer slab OS) performing the rolling in the
rolling device 30 is provided as in a continuous form of being
connected to the continuous casting device 10 or in a discontinuous
form of being separated from the continuous casting device 10. To
this end, the cutting device 20 is provided on an outlet side of
the continuous casting device 10.
[0045] That is, when the cutting device 20 and allows the inner
slab IS to freely pass without cutting the same, the rolling device
30 receives the inner slab IS produced in the continuous casting
device 10 in the continuous form of being connected to the
continuous casting device 10 to perform the rolling. When the
cutting device 20 cuts the inner slab IS and transfers the same to
the rolling device 30, the rolling device 30 receives the inner
slab IS in the discontinuous form of being separated from the
continuous casting device 10 to perform the rolling.
[0046] When the rolling device 30 stops due to an abnormal
operation, the inner slab IS needs to be introduced onto the
supplementary path SP. In this regard, the cutting device 20 cuts
the slab.
[0047] The rolling device 30 receives a slab, such as the inner
slab IS produced in the continuous casting device 10 or an outer
slab OS provided from outside, and presses the same to produce a
natural or after product.
[0048] To this end, the rolling device 30 can allow the slab to go
through a pair of rolling rolls to roll the slab, and several
rolling stands providing such a pair of the rolling rolls may be
provided.
[0049] As described above, the rolling device 30 can roll the slab
while setting various rolling thicknesses.
[0050] The rolling device 30 may be provided as a rough rolling
device 30 and a finish rolling device 30. The rough rolling device
30 has a configuration in which a slab produced in the continuous
casting device 10 is first rolled, whereas the finish rolling
device 30 has a configuration in which the slab rolled in the rough
rolling device 30 is finish-rolled.
[0051] When the rolling thickness for the slab is satisfied by the
rough rolling device 30, the finish rolling device 30 does not
perform the rolling but may allow pairs of the rolling rolls to
freepass the slab. Alternatively, when the rolling thickness for
the slab is formed only by the operation of the finish rolling
device 30, the rough rolling device 30 does not perform the rolling
but may allow the pairs of the rolling rolls to freepass the
slab.
[0052] A heater for adjusting a rolling temperature of the slab or
a scale-remover removing a scale may be provided on the inlet side
of the rough rolling device 30 or the finish rolling device 30.
[0053] The tunnel furnace 40 serves to maintain or increase a
rolling temperature of the slab when transferring the slab to the
rolling device 30 and rolling.
[0054] To this end, the tunnel furnace 40 is provided between the
continuous casting device 10 and the rolling device 30 and heats
the slab, such as the inner slab IS produced in the continuous
casting device 10 or an outer slab OS provided from outside, to
maintain or increase the rolling temperature of the slab.
[0055] In another aspect, as a cooling speed can be adjusted as the
temperature of the slab increases or a heating amount decreases, a
material of the slab can also be adjusted.
[0056] To this end, the tunnel furnace 40 may be provided with a
heating means such as a gas heating method, an induced heating
method, or the like, and the tunnel furnaces 40 may be provided in
plural according to a length thereof.
[0057] In particular, the slab is separated to the supplementary
path SP from the main path MP of the inner slab IS delivered to the
rolling device 30 from the continuous casting device 10 the tunnel
furnace 40 on the outlet side of the tunnel furnace 40. In the
meantime, the loading adjustment unit 50 introducing the slab from
the supplementary path SP onto the main path MP may be connected to
the inlet side of the tunnel furnace 40.
[0058] The loading adjustment unit 50 serves to separate a slab
from the main path MP to be introduced onto the supplementary path
SP on the outlet side of the tunnel furnace 40 while separating the
slab from the supplementary path SP onto the main path MP on the
inlet side of the tunnel furnace 40. This is to prevent the
problems that the slab is scrapped and the actual yield thereof is
lowered in presence of a defect of the rolling device 30 or a
scrapped slab during an abnormal operation in which a rolling
operation such as a replacement of a transfer roll, by expanding
the path on which the slab remains to the supplementary path SP.
This enables the slab to remain on the main path MP and the
supplementary path SP without being abandoned until the operation
is back to normalize.
[0059] To this end, the loading adjustment device may include a
drawing device 51 and an introducing device 52. That is, the
loading adjustment unit 50 of the continuous casting device
according to an exemplary embodiment of the present invention is
provided adjacent to the outlet side of the tunnel furnace 40 and
to the inlet side of the tunnel furnace 40 and the drawing device
51 separating the slab from the main path MP to be introduced onto
the supplementary path SP. The loading adjustment unit 50 may
include the introducing device 52 receiving the slab through the
supplementary path SP to be introduced onto the main path MP.
[0060] The drawing device 51, located on the outlet side of the
tunnel furnace 40, serves to deliver the slab from the main path MP
to the supplementary path SP. Accordingly, the moving path of the
slab is expanded by changing the moving path of the slab toward the
rolling device 30 from the outlet side of the tunnel furnace 40 to
the supplementary path SP.
[0061] Such drawing device 51 may include a pusher pushing the slab
on the transfer roll, but is not limited thereto. Any drawing
device 51 can be used in the present invention as long as the slab
can be delivered from the main path MP to the supplementary path
SP.
[0062] The introducing device 52, located on the inlet side of the
tunnel furnace 40, serves to deliver the slab from the
supplementary path SP to the main path MP. Accordingly, the slab
separated from the outlet side of the tunnel furnace 40 can be
delivered toward the rolling device 30.
[0063] Further, as being provided on the inlet side of the tunnel
furnace 40, the introducing device 52 enables the slab to be
heated, thereby increasing the temperature of the slab, which has
lowered while being transferred to the supplementary path SP, to a
temperature at which the slab can be rolled.
[0064] Similarly to the drawing device, the introducing device 52
may include a pusher pushing the slab on the transfer roll, but is
not limited thereto. Any introducing device 52 can be used in the
present invention as long as the slab can be delivered from the
supplementary path SP to the main path MP.
[0065] The loading adjustment unit 50 of the continuous casting
device according to an exemplary embodiment may serve to introduce
the inner slab IS separated from the main path MP of the outlet
side of the tunnel furnace 40 by the drawing device 51 onto the
main path MP of the inlet side of the tunnel furnace 40 by the
introducing device 52.
[0066] That is, an additional configuration is not suggested for
the moving path of the slab transferred from the drawing device 51
to the introducing device 52, and the slab can be configured to
transfer while forming the supplementary path SP directly
connecting the introducing device 52 to the drawing device 51.
[0067] When the supplementary path SP is formed as the above, a
length thereof may be reduced depending on a number of the slabs to
remain.
[0068] The length of the supplementary path SP is defined in
consideration of an amount of the slab cooled on the supplementary
path SP. That is, the temperature of the slab on the inlet side of
the rolling device 30 in consideration of the amount of the cooled
slab reduced on the supplementary path SP and a degree of a
temperature increase in the tunnel furnace 40 added to the slab
needs to be higher than a temperature at which the rolling is
feasible. In such relationship, a maximum distance of the
supplementary path SP is defined.
[0069] FIG. 2 is a layout diagram illustrating a moving path of a
slab compensating for a temperature loss in the continuous casting
and rolling apparatus during an abnormal operation. Based thereon,
the continuous casting device according to an exemplary embodiment
is provided on the supplementary path SP between the drawing device
51 and the introducing device 52 and may include a reheater 60
heating the slab on the supplementary path SP.
[0070] The reheater 60 is further provided on the supplementary
path SP as described above because the range for compensating for
the temperature drop (cooling amount) of the remained slab on the
path in the tunnel furnace 40 is exceeded according to an
increasing amount of the slab, which needs to remain on the
supplementary path SP.
[0071] This is the case in which the inner slab IS produced in the
continuous casting device 10 is prevented from being disposed and
an amount of the inner slab IS remaining on the main path MP or the
supplementary path SP increases in the case of prolonged period of
the abnormal operation.
[0072] Such reheater 60 may be configured as the tunnel furnace 40.
That is, the reheater 60 may be provided with a heating means such
as a gas heating method, an induced heating method, or the like,
and may be provided in plural according to a length of a section
which is heated.
[0073] FIG. 3 is a layout diagram illustrating a moving path for
scarfing of a slab in the continuous casting and rolling apparatus.
Based thereon, the continuous casting device according to an
exemplary embodiment may include a scarfing device 70 provided
between the introducing device 52 and the drawing device 51 on the
supplementary path SP and scarfing the slab on the supplementary
path SP.
[0074] The scarfing device 70 serves to scarf the inner slab IS or
the outer slab OS according to a need of a product to be
produced.
[0075] As an example, as the scarfing device 70 is provided on the
supplementary path SP, not on the main path MP, a problem that a
slab, which does not need to be scarfed, is unnecessarily cooled
due to unnecessary waste of the main path MP is prevented. Further,
selective scarfing is feasible for the slab in need of being
scarfed.
[0076] FIG. 4 is a layout diagram illustrating a moving path for
receiving an outer slab in the continuous casting and rolling
apparatus, and FIG. 5 is a layout diagram illustrating a moving
path for receiving an outer slab and performing scarfing in the
continuous casting and rolling apparatus.
[0077] Based on FIGS. 4 and 5, the introducing device 52 of the
continuous casting device according to an exemplary embodiment is
configured to receive at least one of the inner slab IS produced in
the continuous casting device 10 or the outer slab OP delivered
from outside to introduce the same onto the main path MP.
[0078] That is, the introducing device 52 is not limited to
providing the inner slab IS produced in the continuous casting
device 10 to the rolling device 30 and rolling the same; the
introducing device 52 is configured to introduce the slabs produced
outside, thereby preventing rolling capacity of the rolling device
30 from being wasted. This may serve to increase a production yield
of a product produced by the rolling device 30.
[0079] Further, in consideration of the rolling capacity of the
rolling device 30, a plurality of the continuous casting devices 10
may be connected to a single rolling device 30 to form the main
path MP. In another aspect, a moving path of the slab connecting
the main continuous casting device 10 and the rolling device 30 is
formed as the main path MP, and the slab produced in another
continuous casting device 10 is delivered to the rolling device
through the supplementary path SP.
[0080] When the outer slab OS needs to be scarfed, a moving path
passing the scarfing device 70 may be configured. A moving path
passing the reheater 60 may be configured when additional heating
is required.
[0081] FIG. 6 is a diagram illustrating an order of the continuous
casting and rolling method of the present invention. Based thereon,
a continuous casting and rolling method according to another
exemplary embodiment involves a process of supplying an inner slab,
involving cutting an inner slab produced in a continuous casting
device 10 and supplying the same to a tunnel furnace 40; a rolling
process involving pressing down the slab received from a main path
MP of the slab moving through the tunnel furnace 40; and a
subworking process performed between the inner slab supply process
and the rolling process and involving separating the slab on the
main path MP from an outlet side of the tunnel furnace 40 when the
rolling process stops and introducing the slab onto the main path
MP from an inlet side of the tunnel furnace 40 when the rolling
process resumes.
[0082] The subworking process may serve to prevent a problem of a
reduced actual yield, which may be caused by a defect of the
rolling device 30 or a scrapped slab during an abnormal operation
in which a rolling operation such as a replacement of a transfer
roll is impractical.
[0083] That is, the slab located in the tunnel furnace 40 or that
produced by molten steel remaining in the continuous casting device
10 is separated from the main path MP of the outlet side of the
tunnel furnace 40 to be introduced onto the supplementary path SP
during the abnormal operation. Alternatively, the slab on the
supplementary path SP is introduced onto the main path MP of the
inlet side of the tunnel furnace 40, thereby increasing a time for
which the slab is positioned on a moving path.
[0084] By securing a bypass, on which the slab remains without
entering the rolling device 30, the slab can be prevented from
being wasted by the scrap treatment due to insecurity of the path
on which the slab remains.
[0085] Besides, the slab introduced onto the main path MP is
limited to be introduced onto the inlet side of the tunnel furnace
40, thereby compensating for a temperature of the slab lowered
during its transfer through the supplementary path SP by a
temperature at which the rolling can be performed.
[0086] The process of supplying an inner slab involves producing of
the inner slab IS using molten steel in the continuous casting
device 10, and the rolling process involves pressing down the slab
by the rolling device 30 to produce as a rolling product.
[0087] As previously described, the subworking process involves
producing the supplementary path SP in addition to the main path,
through which the inner slab IS is delivered to the continuous
casting device 10 and the rolling device 30 such that the problem
that the slabs are disposed during abnormal operations is
prevented.
[0088] More specifically, the subworking process of the continuous
casting and rolling method according to another exemplary
embodiment may include a drawing process involving separating the
slab on the main path from the outlet side of the tunnel furnace
when the rolling process stops; and an introducing process
involving receiving the slab separated from the main path of the
outlet side of the tunnel furnace and introducing the same onto the
main path of the inlet side of the tunnel furnace when the rolling
process resumes.
[0089] That is, the drawing process involving delivering the slab
from the main path MP to the supplementary path SP, and the
introducing process involving delivering the slab from the
supplementary path SP to the main path MP, are suggested.
[0090] The drawing and introducing processes are performed while
not allowing another process to intervene therebetween such that an
additional process is not performed on the supplementary path SP,
and this facilitates a configuration of the slab remaining on the
path.
[0091] That is, the subworking process of the continuous casting
and rolling method according to another exemplary embodiment
includes the introducing process subsequent to the drawing process
so as to exclude intervention of another step therebetween, when
the slab introduced onto the main path maintains a temperature for
rolling when the slab introduced onto the main path maintains at
least a temperature for rolling.
[0092] The subworking process is performed for a case in which a
period of time for the abnormal operation is short enough that a
cooling amount can be compensated in the tunnel furnace 40 while
the slab remains on the supplementary path SP.
[0093] However, in the case of a prolonged period of the abnormal
operation, the cooling amount of the slab remaining on the
supplementary path SP increases, thereby disabling to secure the
rolling temperature. In this case, the slab is reheated between the
introducing and drawing processes.
[0094] That is, the subworking process of the continuous casting
and rolling method according to another exemplary embodiment may
include a reheating process performed before the introducing
process and involving heating the slab introduced onto the main
path MP during the subworking process on the supplementary path SP
when the slab has a temperature below the rolling temperature.
[0095] The reheating process may be performed in the reheater 60
provided on the supplementary path SP.
[0096] In addition, the subworking process of the continuous
casting and rolling method according to another exemplary
embodiment may include a scarfing process performed before the
introducing process and involving scarfing the slab separated from
the main path MP of the outlet side of the tunnel furnace 40 on the
supplementary path SP through which the slab piece is delivered to
be introduced onto the main path MP of the inlet side of the tunnel
furnace 40.
[0097] The scarfing process may be performed in the case of
producing an exterior material of a vehicle or a product required
to meet stringent surface quality requirements.
[0098] To this end, the scarfing process is performed in a scarfing
device 70 provided on the supplementary path SP. This may prevent a
problem of the main path MP elongated by the scarfing device 70 as
well as a problem of the slab on the main path MP being cooled.
[0099] Further, the subworking process of the continuous casting
and rolling method according to another exemplary embodiment may
include a process of supplying an outer slab, performed before the
introducing process and involving introducing the outer slab OS
produced outside onto the supplementary path SP through which the
slab separated from the main path MP of the outlet side of the
tunnel furnace 40 is delivered to be introduced onto the main path
MP of the inlet side of the tunnel furnace 40.
[0100] That is, the subworking process is not limited to providing
the inner slab IS during the inner slab supply process, and further
includes supplying an outer slab OS introduced from outside.
[0101] The process of supplying an outer slab supply is further
performed such that the problem of capacity of the rolling device
30 being wasted is prevented.
[0102] That is, the outer slab supply process of the continuous
casting and rolling method according to another exemplary
embodiment is performed when capacity of the slab pressed during
the rolling process is larger than an amount of the inner slab IS
being supplied.
[0103] While embodiments have been shown and described in detail
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 disclosure as defined by the appended
claims.
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