Note: Descriptions are shown in the official language in which they were submitted.
The present invention relates to a continuous casting
installation for metals, especially steel.
A considerable difficulty in obtaining a high degree
of utilization of a continuou~ casting installation is to
provide efficient coordination between the tapping cycles of
the steel production assembly and the casting cycle~ of the
continuous casting installation. The casting cycles consist
of the casting time and the tran3ition time between two pours.
During the transition time it is particularly nece~sary that
the hot ~trand end be withdrawn, the dummy bar introduced into -
- the roller apron or strand guide arrangement and ~ealed in the
mold. ~hi~ tran~ition time disadvantageously influence~ the
utili~ation factor or available casting time of the installation.
~he available ca~ting time is, however, also negatively affected
by predictable interruptions, ~uch a~ changes in the section or
6hape of the strand and/ox quality changes and so forth, aq
well as also by non-predictable interruptions, such as metal
break-out and the like~ ~`
It is known to increa~e the utili~ation factor of
a oo~tinuous casting installation by means of sequential pours,
becau~e in this way the transition time from one pvur to the
next only comes into play when casting metal into the first
ladle. Sequential pour3 or sequence ca~ting is, howe~er, only
; pos~ible with an exact coordination of the tapping times of the
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~teel production assembly and the casting time~ at the
continuou~ casting installation. It i8 never po~sible to
completely a~oid disturbances which affect such coordination.
Also, sequence ca~ting is only usual with melts of the same
stecl quality as well a~ unaltered strand ~ection or shape.
Interruption of sequence casting or sequential pours occurs
upon dama~e to refractory parts of the installation, metal
break-out or other disturbances. In the case of steel plants
,;
where the production conslderably varies narrow limits are thus
placed upon sequence casting and therefore the utilization
of the continuous casting in~tallation.
There is known to the art a continuous Gasting
installation, whose at least partially curved roller apron
is subdivided, and at two displacement carriages there is
arranged at least one respective unit or assembly con~isting of
a mold a~d a first roller apron portion merging therewith. ;
;~ The displacement carriages can be alternately brought into a
casting position and a preparatory position. ~he unit which is
momentarily located in the casting position cooperates with the
stationary second part of the roller apron. Connected with the ~ -
displacement caxriages are casting platform covers which cover
the di~placement path of such di3placement carriages betwsen the
castlng position and the preparatory positions. With this
continuous casting installation the dummy bar is introduced by
means of an infeed device in one of both preparatory positions
into the unit~ The roller apron part of the unit is provided
for thia purpose with a holding - and tra~port mechanism for
the dummy bar. Each of both displacement carriages i9 therefore
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equipped with an electrical or hydraulic drive and with infeed
llnes leading to appropriate supply netwQrks. ~he existence
of such flexible infeed lines complicates the continuous casting
installation and, furthermore, renders such also expensive due
to the need to equip each uni+, with such drives. Furthermore,
the transport mechanism between the uncouplin~ location and ~`~
the infeed locations for the dummy bar located in the preparatory
po~itions is expenaive. A further drawback of this construction
resides in the fact that repairs in the pxeparatory position, ; ?
laating longer than the casting time of the pour which i9
taking place, result in an i~crease in the transition time
because the dummy bar cannot be introduced during the repair
:~q~
time. In these instances, it i9 thus not possible to obtain
optimum tran~ition times. Due to the co~nection of the casting
platform covers with the displacement carriages, the casting
platform cover is shifted away for a certain period of time
during each transition time7 producing open pits or the like.
Such temporarily formed pit~ increa~e the danger of accidents
occurring at the casting platform, and therefore~ it is necessary
to erect pit barriers or the like. These barriers, in turn,
however reduce the useful area of the casting or teeming platform
and disturb the casting operation.
It is therefore a general object of the present
invention to provide a new and improved construc~ion of a
- continuou~ casting i~stallation which is not as~ociated with
the aforementioned drawba¢ks and limitations o~ the prior art
constructions.
Another and more specific object of the present
invention aims at eliminating the a~orementioned drawbacks and
providing a continuous casting installation having increased
utilization factor with frequent change in the strand ~ection
- 20 or shape and in the presence of disturbances, a~d ~urthermore,
improving the configuration of the casting or teeming platform
and reducing the danger of accidents.
Still a further significant object of the pre~ent
invention aims at simplifying the return o~ the dummy bar to the ~ ;
roller apron or strand guide arrangement and into the mold as
well as simplifying the total construction of the continuous
casting installation and its operation.
Now in order to implernent these and still further
object~ of the invention, which will becorne more readily apparent 30 as the description proceeds, the invention provides a continuous
casting installation ~or metals, especlally steel, which i9
generally of the type comprising a movable tundish, a subdivided,
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at least partially curved roller apron, a withdrawal and
~traightening machine, and a runout roller table. '~here are
pro~ided two displacement carriages which c~n be selectively
brought into a casting position and a preparatory position.
At each displacement carriage there is arranged at least one
unit or assembly con~isting of a mold and a first part of the
roller apron following such mold. The unit momentarily located
in tis casting poqition cooperate~ with a stationary second
part of the roller apron. Further, there are provided casting
platform covers or cover members arranged above the displacement -~
path of such displacement carriages between the casting
position and the preparatory positions. According to the -
; invention, the casting platform covers are arranged independent
of the displacement carriages and there are provided devices or ~-
means for infeeding a dummy bar which cooperate with the unit
located in the ca3ting position~
With such continuous ca~ting installation, it is possi~
ble to obtain transition times in the order of twenty minutes and
less when changing the strand section or shape between successive - -
pours. But also in the case of di~turbances, such as in parti~
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cular metal brea~ outs, there ca~ be realized short tran~ition
times by ex~hanging the units by means of the displacement
carriage~. In addition to these advantages, the displacement
carriages and the units or as~emblies located thereat are
extremely ~imple in construction and they neither po~ses~ drive
elements nor energy infeed line~ as~ociated therewith. In the
case of multi-strand installations the units associated with
0ach strand can be constructed at both of the displacement carriage~
~o as to have minimum strand 3pacing. There thus result3 a
compact construction possessing ~hort flow paths for the liquid
steel between the ladle and the mold and also small tundi~he~.
Moreover, there can be carried out in one of the preparatory
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positions comprehensive repairs during repair times amounting
to a number of succe~qsive pouring or ca~ting cycles, such a~
cleaning of the roller apron after a break-out, without
increasing ~he transition time, because there is no disturbance
of the infeed of the dummy bar to the unit located in the casting
position. Due to the inventive construction of the casting
platform covers, there does not exist during the travel time any
relative movement between the di~placement carriages and the
casting or teeming platform. ~here is avoided the temporary
formation of pits at the casting platform between the casting
and preparatory positions as well as barriers or the like
around ~uch pits. Dhe u~eful surface of the casting platform is
therefore increased and detrime~tal hindering of the castin~
operation i9 also precluded. A further advantage i~ additionally
realized by virtue of the fact that shifting of the displacement
carriages is only neces~ary when changing the shape or section
of the cast strand and in the preaence of disturbances. ;~
It is especially advantageoua if the casting platform
cover is constructed as a tunnel which, in contrast to the casting
platform, form~ a casting platform floor arranged at a greater
elevation. With thi~ ~olution the casting platform co~er
remains stationary even during travel of the displacement ~;
carriages. It i~ also readily possible to utilize the
casting platform floor arranged at the greater elevation for
handling or worki~g on the tundish or a~ a deposit sur~ace.
I~ for certain reasona a ca~ting platform floor ~- ;
arranged at a greater elevation ~hould be di3advantageous,
then it i3 poa~ible according to a further a~pect o~ the
invention, to arrange the casting platform cover to be
pivotable in order to provide the neces~ary travel clearance
for the displacement carriage. It is readily pos~ible to
conatruct the pivotable ca~ting platform covers such that
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they do not form at any location of the ca~ting or teeming
pla~form openlngs which could con~titute the source of an
accident.
In order to reduce the tranqition time between -
~equential pours, it i~ advantageous, according to a further
facet of the invention, if the first roller pair, viewed in the
direction of travel of the strand, of the stationary roller
apron part pos~e~eq at lea~t one driving roller and directly
thereafter there is provided an infeed location for a short
dum~y bar, and if there are arranged after the withdrawal and
straightening machine or unit an uncoupling location for the
dummy bar and between the uncoupling location and the infeed
location devices or mean~ ~or the infeed of the dummy bar. ~he
transition time, with ~uch type co~tinuous casting in~tallation~ ~
- can b~ reduced by at lea~t an additional five minutes. The ~-
device~ or ~eans for the infeed of the dummy bar advantageously
comprise a crane cooperating with a curved roller guide and
an infeed table arranged upon an intermediate platform.
It is po~sible to obtain a particularly favorable
geometry of the equipment between the mold and the first roller
apron part~ if the displacement carriages are con~tructed a~
semi-gantry or ~emi-portal carriage~ a~d es~entially con~ist
; of a vertical support or carrier at which there are secured the
o~cillating mold and the roller apron part.
In order to en~ure for a faultle~s alignment between ~ ;
the roller apron part located at the associated di~placement
j ~, ,
carria~e and the stationary ~econd part o~ the roller apron,
it i~ adva~tageou~ if the di3placement carriages, when in
their ca~ting position, are shifted by power devices against
adjustment stop~ provided at the frame of the continuous ca~ting
installation.
In order to ensure that the introduction of the dummy
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bar into the unit occurs before -the cast ~trand has departed
from the driving arrangement, it i5 possible according to a
further feature of the invention, to driv~ the driving roller~
a~sociated with the infeed location for the dummy bar and the
rollers of the withdrawal and ~traightening machine both
synchronou31y a~ well a3 also independently of one another.
me invention will be better understood and objects
other than those set forth above, will become apparent when
consideration is given to the following detailed description
thereof. Such description makes reference to the annexed
drawinga wherein~
Figure 1 is a ~chem~tic vertical ~ection~l view
through a continuou~ ca~ting in~tallation constructed according
to the teachings of the present invention;
~ igure 2 i~ a top plan view of the continuous casting
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in~tallation shown in Figure l; and
~igure 3 is a fragmsntary ~ertical sectional view
through another embodiment of the invention. ;
` Describing now the drawing~, it is to be understood
that only enough of the co~tinuous casting installation has
bee~ shown in order to enable those qkilled in the art to
~; readil~ under~tand the underlying principles and concepts of
the present invention. Further, it is to be appreciated that
~i there ha~ been illu3trated by way of example a twin-~trand
casting machine or installation, although the principles of
ths invention are equally applicable to other ca3ting installations,
~uch a~ a ~ingle strand casting machine. It will be seen in
particular by referring to Figure~ 1 and 2 that a movable tundi3h
, 2 i8 arranged above the two mo~d~ 1, 1'. Since the construction
of the casting installation i~ ba~ically the same for each
strand9 it will suf~ice to generally consider the component~
- a~ociated with one of the ~trand~. ~hus, it will be recognized
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that following the mold 1 there i~ a roller apron or strand . .
guide arrangement 3, a withdrawal and ~traightening machine
or unit 4, and a runout roller table 5. ~he roller apron 3
is provided with the usual secondary cooling devices, such as
the schematically illustrated spray nozzles 40. Between the
mold 1 and the withdrawal and ~traightening ~achi~e 4, there are
arran~ed additional paix~ of driving rollers 8 and 9 which are
driven by the ~chematically illu~trated drive motor~ 8a, 9a
respectively. ~he driving roller pair 8 located closest to the
mold 1 has directly following thereat an infeed location 10 for
a ~hort dummy bar 11. After the withdrawl and straightening
machine 4 there is arranged an uncoupling location, generally
indicated by the arrow 12 for the dummy bar 11. Between
the uncoupling location 12 and the infeed location 10 there
are provided the hereinafter discussed transport devices or ?
tran~port means for infeeding the dummy bar 11 into the unit
... 20 located in the casting position, which unit 20 compri~es the
:
:; roller section 21 a~d the associated mold 1. ~he transport
device3 may comprise, by way of example, a crane 14 or equivalent
3tructure arranged above the runout roller table 5, which lifts
the dummy bar 11 from the runout roller table 5 and thereby
~imultaneou~ly uncoupleq the dummy bar 11 from the ca~ strand 15.
; .
By means of a curved roller guide 16, also constituting part of
the transport means, pivotable about the shaft 13 it is possible
for the dummy bar 11 to be deposited upon an infeed table 17,
equally constituting part of the transport means, and arranged
above the withdrawal and straightening machine 4, as such
ha~ been shown in phantom lines in Figure 1. This infeed
table 17 can be displaced upon an intermediate platform 7
towards the infeed location 10 and by means of a drive 19 the
dummy bar 11 can be shifted from the infeed table 17 into the
. operable region of the driving roller~ or rolls 8. ~-
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Above the driving rollers 8 which are secured at the
machine frame and associated with th~ infeed location 10 there
are movable, tran~versely with respect to the direction of
travel of the strand 15, two di~placement carriages 22, 22'
or equivalent s-tructure. The displacement carriage 22 is
shown in the casting position 23 in Figure 1, and the displacement
carriage 22' is shown in the preparatory position 24 in
Figure 2. As mentioned previously, the exemplary embodiment of
continuous casting installation depicted in Figures 1 and 2 serves
to ca~t two strands. ~herefore, at each of the two displacement
carriages 22S 22' there are mounted a respective unit 20
consi~ting of a respective mold, 3uch as the mold 1, and its
following first roller apron part or portion, such as the roller
apron part 21. ~he displacement carriages, 22, 22' can be
alternately brought into the casting position 23 and into one of
the preparatory positions 24, 24'. The unit or assembly 20
located in the casting position 23 cooperates with the stationary
second part o~ the roller apron or strand guide arrangement 3.
This stationary second part of the roller apron 3 starts at the
pair of driving roller~ 8 and ends at -the uncoupling location 12.
Between the casting position 2~ and the preparatory
positions 24 and 24' respectively, the casting or teeming
platform 6 is provided with casting platform covers or cover
members 18 which are arranged independently of the displacement
carriages 22, 22'. Each such casting platform 18 is constructed
a~ a tu~nel and provide~, in relation to the casting platform 6,
a castin~ platform floor arranged at a greater elevation. ~ach
such casting platform cover 18 is fixedly connected in any
convenient manner, such as by botts or other fa~tening mean~,
with the ca~ting platform 6.
The displacement carriage 3 22, 22' are constructed as
semi-gantry carriages and each essentially comprise a vertical
_g_
support or carrier 25. ~he di~placeme~t carriage~ 22, 22' are
e~sentially linearly displaceable along the railB 26, 26', 26 ",
and the displace~ent carriage 22' can be ~hifted in each
in~tance between the preparatory position 24 and the casting
po~ition 23, whereas the d.isplacement carriage 22 can be
shifted bet~Jeen the casting position 23 and the preparatory
: position 24', ~t the vertical support 25 there are attached
the associated oscillating molds 1, 1' as well as also the ~:
roller apron parts 21, 21'. A schematically illustrated ~: :
oscillation drive 27, which i~ connected at the casting position
23 with the foundation, can be coupled and uncoupled with an :
oacillation lever 29 by means of a piston and cylinder unit 28.
In order to fixedly clamp and simultaneouæly adjust
the displacement carriage 22 located in the casting position 23,
this di~placement carriage 22 is shifted by mean~ of a power ~-~
; device 30 against adjustment stops 31 provided at the machine ~:
frame, generally indicated b~ reference character 50. ~he ,~
roller apron part 21 is thus aligned with the driving rolls 8 ~`
located therebelow, ,~ :
~he roller~ 32 of the withdrawal and straightening ~ .
t `:'~
machine 4 are provided with the schematically illustrated
roller drives 32a. ~he driving roller~ 8 as~ocaited with the `.
infeed location 10 for the dwnmy bar 11 and the rollers 32
of the withdrawal and ~traightening machine 4 are driven ,.
synchron.ou~ly and independently of one another with the aid of a
suitable drive control, as schematically indicated by reference
character 550 This enables outfeeding a cast strand 15 located
below the driving roller~ 8 and at the 6ame time introducing the
dummy bar 11 into the unit 20 by means of the aforementioned ;
30 driving rollers 8, If after the start of casting the dummy bar 11 .~ ~:
leaves the driving rollers 8, then the contact force o~ the ;~
driving rollers 8 and 9 is appreciably reduced to ~uch an extent
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~ @
that the cast ~trand 15 will not become damaged by such rollers.
In Figure 2 there is 3hown in phantom lines the
tundi~h 2 in casting po~itlon and the tundi3h 2' which ha3
been rocked about a vertical shaft 35 i~ shown located at a
preheating ~tation. When using such pivotable or displaceable
tundishe~, it is possible to maintain small the spacing between
the preparatory po~itions 24, 24'.
Now in Figure 3 there is illustrated a varian-t
arrangement wherein a castlng platform cover or cover member 37
is pivotable about a hinge or pivot shaft 38 for the purpose
of providing the requisite travel clearance for the displacement
carriages 22, 22~. A support wall 39 ensures that during ~he
entire time that the carriages 22, 22' are displaced, there is
not present any pit-like opening in the casting platform between
the casting position 23 and the preparatory positions 24, 24',
thereby eliminating the danger of acciclents.
Having nwo had the benefit of the foregoing -~
description, the operation of the continuous casting machine or
installation shown in Figures 1 and 2 will be considered and
i9 as follows:
By way of example, there will be de~cribed two
succe3sive pours for di~ferent ~trand ~ections or shapes. During
the time that one of the pours is still being completed, the
mold~ 1, 1' of the di~placement carriage 22', which is in the
preparatory po~ition 24, i~ adjusted to the new ~trand section
: . .
which is required for the next pour or casting. After the
departure of the ca~t strand 15 of the exi~ting pour from the
mold~ 1, 1' which are in the casting position 23, it i9 ~ .
po~sible to di~connect by means of the piston and cylinder
unit 28 the oscillation dri~e 27 ~rom the 03cillation lever 29
secured to the di~placement carriage 22. Once the strand 15
has departed from the roller apron part or section 21, then
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a not particularly illustrated bll-t conventional water coupling
plate, which i~ connec-ted with ths carriage 22 and contains
all of the connection~ for the mold cooling water and the
~econdary cooling water, i8 disconnected from the coupling
plate fixedly arranged at the machine frame. By means of
the power de~ice 30 there is released the adjust~ent of the ~ ;
carriage 22. After t.his preparatory work, the carriage 22 i8
shifted by its drive, such as the drive 60 illustrated in
figure 2 for the carriage 22', along the rails 26 into the
preparatory position 24'. Pr.actically at the same time the
~: carriage 22' i9 brought into the casting position 23, adjusted,
the water connection plate coupled and the oscilla-tion drive :
27 connected with the lever 29. ~he infeed table 17 which can .
~ be shifted towards the driving rollers 8, displaces by means . :'~
of the drive 19 the dummy bar 11 which was brought a~ter the
:~ start of ca~ting onto the infeed table, between the driving ~ :~
rollers 8. These driving rollers 8 then convey the dummy bar 11 :~;
into the unit 20. The dummy bar head is sealed in conventional
manner at the mold and there can now be started the next pour or
casting operation ~or the new strand shape or section. The .
- ;.:::
above-enumerated operations are carried out during such time as
the existing pour or teemed metal is being discharged from the .
. tundish. The required tran~ition time, even in the ca~e of
multi-strand casting in~tallations, is in the order of about 15 ~ :
.: minutes between the closure of the tundish for the old pour and ...
opening of the tundish for the new pour. ~:~
A~ter a break-out the exchange of the displacement.
; carriage~ 22, 22' is carried out in the same manner, and a~
a general rule the ~-trand 15 i~ severed between the driving
roller~ 8 ~nd the roller apron part 21.
- ~he continuou~ casting in~tallation of the invention ~ ~
is not li~ited to curvilinear or arc-type roller apron~ a~ -
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shown in Figures 1 and 2. The principles of the invention al~o
can be applied to continuous casting installation~ working with
straight moldæ and partially straight roller apron~. With such
an installation the dummy bar can be, for instanoe, introduced
from the underside of the roller apron advantageously at the
tran~ition between the straigllt roller apron portion and
the curved roller apron portion.
In the ca~e of slab casting installations, the infeed
location 10 can be provided with displaceable rollers for
opening and cloqing ~uch infeed loeation. Moreover, the return
of the du~my bar i9 not limited to the po~ibilities shown by
way of example in Figures 1 and 2. It can be advantageous
to use a long dummy bar which is introduced for instance through
the withdrawal and ~traightening machine, or to in-troduce the
dummy bar through the mold according to conventional solutions.
While there are shown and described present prefer~ed
embodiments of the invention, it is to be di~tinctly understood -
that the invention is not limited thereto, but may be otherwise
variou~ly embodied and practiced withi~ the ~cope of the
~o lowing claims.
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