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EP 1 337 361 B1 |
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EUROPEAN PATENT SPECIFICATION |
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Mention of the grant of the patent: |
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02.06.2004 Bulletin 2004/23 |
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Date of filing: 06.10.2001 |
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International application number: |
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PCT/EP2001/011535 |
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International publication number: |
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WO 2002/036290 (10.05.2002 Gazette 2002/19) |
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CONTINUOUS CASTING MOULD WITH OSCILLATION DEVICE
STRANGGIESSKOKILLE MIT OSZILLATIONSVORRICHTUNG
MOULE DE COULEE CONTINUE A DISPOSITIF D'OSCILLATION
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Designated Contracting States: |
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AT CH DE GB IT LI NL |
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Priority: |
31.10.2000 LU 90666
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Date of publication of application: |
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27.08.2003 Bulletin 2003/35 |
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Proprietor: PAUL WURTH S.A. |
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1122 Luxembourg (LU) |
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Inventors: |
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- HOUBART, Michel
B-4540 Amay (BE)
- ASSA, Charles
7423 Dondelange (LU)
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Representative: Schmitt, Armand et al |
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Office Ernest T. Freylinger S.A.,
B.P. 48 8001 Strassen 8001 Strassen (LU) |
(56) |
References cited: :
WO-A-98/53935 US-A- 4 669 525 US-A- 5 715 888
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US-A- 4 483 385 US-A- 5 676 194
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Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
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[0001] The present invention relates to a continuous casting mould with oscillation device,
in particular for a continuous steel casting machine with a curved casting axis in
a vertical casting plane.
Background of the invention
[0002] A conventional casting mould for a continuous steel casting machine with a curved
casting axis typically includes a copper mould tube, which forms a curved casting
channel along said curved casting axis, a mould housing surrounding the mould tube
and a water cooling system within the mould housing for vigorously cooling the mould
tube.
[0003] It is known to axially oscillate such a continuous casting mould in order to avoid
sticking of the solidified shell to the mould tube, which would indeed result in surface
defects in the cast strand and can even produce a liquid steel breakout. Experience
has shown that best casting results are obtained if the continuous casting mould is
subjected to axial oscillations with a frequency between 100 and 600 cycles per minute
and an amplitude of 5 to 10 mm. Furthermore, the path of these axial oscillations
should follow as closely as possible the curved casting axis. Oscillation components
in a direction transverse to the casting axis not only result in a poor surface quality
of the cast strand, but also in an excessive wear of the mould tube.
[0004] In most prior art continuous steel casting machines, the continuous casting mould
is supported on a so-called oscillating table located below the mould. Striving to
produce oscillations along a curved casting axis, designers of such oscillating tables
have devised very complex and cumbersome lever mechanisms for oscillating the support
table of the mould. However, most of these oscillating tables do not completely succeed
in avoiding the generation of transverse oscillations of the mould tube. Furthermore,
due to the high masses to be oscillated and to high frictional loss in the lever mechanism,
these oscillation tables are generally inadequate for producing oscillations with
frequencies higher than 200 cycles per minute.
[0005] US patent 5,715,888 describes a solution for replacing oscillation tables with a
more compact and more efficient oscillation device. This oscillation device comprises
an external support casing in which the continuous casting mould is axially supported
by means of an annular, double acting pneumatic or hydraulic cylinder. The latter
consists of two co-axial sleeves, which surround the continuous casting mould. These
sleeves are axially movable relative to each other and are guided in this movement
by a guiding device arranged between them. The housing of the continuous casting mould
defines a shoulder with which it rests on the inner sleeve, whereas the outer sleeve
is supported in the external support casing. It has to be appreciated that this compact
oscillation device allows to impose on the continuous casting mould oscillations with
an amplitude of up to 10 mm and frequencies higher than 200 cycles per minute. A drawback
of this oscillation device is that the manufacturing of a big diameter annular pneumatic
or hydraulic cylinder is rather expensive, in particular if the annular cylinder has
to produce oscillations along a curved oscillation path.
[0006] US patent 5,676,194 describes a solution for making oscillation tables superfluous
by integrating the oscillation device in the continuous casting mould. A double-armed
oscillating lever, which is pivotably supported by the mould housing, supports with
one arm the mould tube within the mould housing and is connected with the other arm
to a linear cylinder located outside the mould housing. Sealing elements, as e.g.
metal diaphragms, are connected between the stationary housing and the mould tube,
so as to allow an axial oscillation of the mould tube by means of the oscillating
lever, while ensuring the sealing of a sealed cooling chamber around the mould tube.
It follows that the mass to be oscillated is substantially reduced, that higher oscillation
frequencies can be achieved and that the power consumption for oscillating the mould
tube is reduced.
[0007] US patent 4,483,385 describes another solution for making oscillation tables superfluous
by integrating the oscillation device in the continuous casting mould. The curved
mould tube is surrounded by a housing including a spray cooling system for the mould
tube. The lower end of the mould tube freely traverses a bottom opening of the housing.
The upper end of the mould tube is secured to a substantially horizontal top plate.
The latter is guided in four vertical guide pins protruding from a top frame of the
housing. Two vertical cylinders are arranged in the mould housing on opposite sides
of the mould tube. When activated, these two vertical cylinders lift the guided top
plate from the top frame. Gravity causes the top plate to fall back onto the top frame,
when the cylinders are deactivated. By activating and deactivating the two cylinders
it is thus possible to subject the freely suspended mould tube to an oscillating up
and down movement within the housing containing the spray cooling system. A serious
disadvantage of the continuous casting mould described in US patent 4,483,385 is that
the vertically oscillated curved mould tube exerts important lateral forces on the
curved strand. These lateral forces result in excessive wear of the mould tube and
surface deformations of the strand. They may even produce a break through of liquid
metal.
Object of the invention
[0008] A technical problem underlying the present invention is to provide a compact continuous
casting mould that is capable of producing oscillations along a curved casting axis
without exerting significant lateral forces on a strand leaving the curved mould.
This problem is solved by a continuous casting mould as claimed in claim 1, which
preamble is based on the closest prior art US-A-4 483 385.
Summary of the invention
[0009] The casting mould of the present invention comprises, in a manner known per se, a
mould tube, which forms a curved casting channel along a curved casting axis of a
casting machine, and a mould housing, which surrounds the mould tube and houses a
cooling system for vigorously cooling the mould tube. The mould tube has a support
flange at is upper end. A pneumatic or hydraulic actuator means is connected between
the support flange of the mould tube and the housing for axially supporting and oscillating
the mould tube in its stationary housing. In accordance with an important aspect of
the present invention, the continuous casting mould further comprises a guiding device
that is connected directly between the lower end of the mould tube and the bottom
end of the mould housing. This guiding device imposes a curved oscillation path on
the lower end of the mould tube (i.e. it fixes, at least in the casting plane, all
translational and rotational degrees of freedom of the lower end of the mould tube),
wherein the imposed oscillation path follows exactly the curved casting axis. In other
words, the guiding device warrants that the oscillations of the mould tube, which
are imposed on the upper end of the mould tube, result in oscillations of the lower
end of the mould tube that strictly follow the curved casting axis. Consequently,
the mould tube exerts no or at least no significant lateral forces on the curved strand
leaving the mould. Within this context it remains to be noted that the oscillations
imposed on the upper end of the mould tube must not necessarily follow exactly the
path imposed on the lower end of the mould tube. Indeed, as the mould tube, which
is normally made of copper, is not a very rigid body, it can easily compensate differences
in the imposed oscillation paths of its lower and upper ends by small deformations
transversal to the casting axis. It will be appreciated that these small transversal
deformations do not deteriorate casting quality and do not result in an increased
wear of the mould tube, because they mainly affect the upper mould tube where the
steel is still entirely liquid.
[0010] The guiding device is preferably forcedly cooled and comprises, in a preferred embodiment,
at least one guiding element, which is fixed to the housing and includes a curved
guiding channel, and a guided element, which is rigidly secured to the mould tube
and guided in the curved guiding channel of the at least one guiding element. The
guiding channel fixes all translational and rotational degrees of freedom of the guided
element, so that the oscillations of the lower end of the mould tube strictly follow
the curved casting axis.
[0011] The pneumatic or hydraulic actuator means is advantageously an annular, i.e. ring-shaped,
pneumatic or hydraulic actuator cylinder, which is preferably forcedly cooled, so
that it can directly surround the hot support flange of the mould tube. It will therefore
be appreciated that the annular cylinder can have a much smaller diameter than the
annular cylinder disclosed in US patent 5,715,888, which is integrated in a support
casing surrounding the whole housing of the mould. It will further be appreciated
that the annular cylinder must not be able to produce oscillations along a curved
path in the mould of the present invention. In other words, it can simply produce
small strokes in a direction parallel to a rectilinear central axis. If this rectilinear
central axis is substantially tangential to the curved oscillation path, the annular
cylinder can-along its relatively small oscillation path-transmit substantially axial
oscillation forces to the mould tube.
[0012] The upper end of the mould tube can be secured with functional play to the annular
cylinder, so that oscillatory deformations of the tube are reduced or even completely
avoided. It is however generally preferred to rigidly secure the mould tube to the
annular cylinder in order to avoid any uncontrolled axial movement of the mould tube.
[0013] In order to reduce deformations of the mould tube at its upper end, the annular cylinder
is advantageously supported on the top end of the housing so as to be capable of oscillating
about an axis of rotation that is substantially perpendicular to the vertical casting
plane and intersects the curved oscillation path. In a preferred embodiment, the annular
cylinder e.g. has two journals and the top end of the housing has two bearings for
receiving the journals. To reduce oscillatory deformations of the upper end of the
mould tube, the annular cylinder may also be fixed to the top end of the housing,
so as to allow small linear displacements parallel to the vertical casting plane and
transversal to the casting axis.
[0014] The cooling system of the mould is advantageously a spray cooling system. In a preferred
embodiment of such a spray cooled continuous casting mould, a ring element is fixed
to the lower end of the mould tube and arranged in a central cut-out of a bottom plate
of the housing, so that a radial gap subsists between the ring and the bottom plate.
As the lower end of the tube is guided by the guiding device, this radial gap remains
substantially constant and may therefore be sealed with an adequate sealing element.
Brief description of the drawings
[0015] The present invention will now be described, by way of example, with reference to
the accompanying drawings, in which:
- Fig. 1:
- is a first schematic longitudinal section of a continuous casting mould with a curved
casting axis, wherein the vertical section plane includes the curved casting axis
and is identified by section line A-A in Fig. 3;
- Fig. 2:
- is a second schematic longitudinal section of the continuous casting mould of Fig.
1, wherein the vertical section plane is perpendicular to the section plane of Fig.
1 and is identified by section line B-B in Fig. 3; and
- Fig. 3:
- is a schematic cross section of the continuous casting mould of Fig. 1 & 2, wherein
the section line is identified with letters C-C in Fig. 1 & 2.
Detailed description of a preferred embodiment
[0016] The Figures show a continuous casting mould 10 for casting steel billets in a continuous
casting machine. This continuous casting machine defines a curved casting axis 11
in a vertical plane. It will be noted that the curved casting axis 11 physically corresponds
to a substantially circular curve defined by the neutral axis of a bent strand in
the casting machine.
[0017] Reference number 12 globally identifies a curved mould tube for receiving molten
steel from a tundish (not shown), i.e. a refractory-lined liquid steel distributor,
which is placed over the mould 10. This mould tube 12 comprises a copper tube 14 fixed
with its upper end to a support flange 16, which forms a kind of inlet funnel 18.
As shown on Fig. 1, which is a section along the vertical casting plane containing
the casting axis 11, the copper tube 14 forms a casting channel 20 along the curved
casting axis 11. In most continuous casting machines, the curved casting axis can
be equated in this region to a circular segment with a radius between 4 m and 12 m.
[0018] Reference number 24 globally identifies a cylindrical mould housing surrounding the
curved copper tube 14. This mould housing 24 houses a known spray cooling system 26
for vigorously cooling the copper tube 14. This spray cooling system 26 comprises
a set of vertical cooling water pipes 28 extending from an annular collector at the
bottom end of the housing 24 to its top end. Each of these pipes includes a series
of spray nozzles 29, which serve to spray the copper tube 14 with cooling water.
[0019] Reference number 30 globally identifies an annular, i.e. ring-shaped, hydraulic cylinder
capable of producing linear strokes. This annular cylinder comprises an outer ring
32 and an inner ring 34. By means of its outer ring 32, the cylinder 30 is supported
on the top end of the housing 24. The mould tube 12 is supported by means of its support
flange 16 on a flange 36 of the inner ring 34. The rings 32, 34 are capable of a rectilinear
movement relative to each other in a direction parallel to a central rectilinear cylinder
axis 35. They cooperate to form an annular piston 38 axially separating two annular
pressure chambers 40, 42, thus forming a double-acting hydraulic cylinder capable
of producing axial forces in two opposite directions (see arrows 44) along the central
cylinder axis 35. It will further be noted that the central cylinder axis 35 of the
annular cylinder 30 is substantially tangential to the curved casting axis 11 at the
point "P" where a plane of symmetry 45 of the two annular piston chambers 40, 42 intersects
the curved casting axis 11. It follows that the annular cylinder 30 can-along its
relatively small oscillation path-transmit substantially axial oscillation forces
to the mould tube 12.
[0020] As best seen on Fig. 2, the outer ring 32 of the cylinder 30 is supported on the
top end of the housing 24 by means of two journals 46, 48. Each of these journals
is received in a bearing 50, 52, which is fixed to the housing 24. The journals 46,
48 and the bearings 50, 52 are arranged so as to define an axis of rotation 54 for
the annular cylinder 30, which is substantially perpendicular to the vertical casting
plane and intersects the casting axis at the point "P" defined above. The outer ring
32 defines an annular gap with a ring-shaped flange 56 of the housing 24, which is
closed by an elastically deformable seal ring 58. It follows that the annular cylinder
30 is capable changing its position by rotating a small angle about its axis of rotation
54, while the elastically deformable seal ring 58 continuously seals the gap between
the outer ring 32 of the cylinder 30 and the ring-shaped flange 56 of the housing
24.
[0021] The inner ring 34 surrounds the support flange 16 of the mould tube 12, wherein there
remains an annular gap between the support flange 16 and the inner ring 34. This annular
gap is at least partially filled with a refractory lining 60, which protects the annular
cylinder 30 against radiant heat from the support flange 16. Heat protection of the
annular cylinder 30 is further improved by equipping both rings 32, 34 with an internal
cooling circuit (not shown) and/or by providing a series of spray nozzles 62 in the
housing 24 for spraying a cooling fluid onto the underside of the annular cylinder
30.
[0022] In Fig. 2 and Fig. 3, reference number 63 globally identifies a guiding device that
is connected directly between the lower end of the copper tube 14 and the bottom end
of the mould housing 24. The object of this guiding device 63 is to impose a curved
oscillation path on the lower end of the copper tube 14, wherein this imposed oscillation
path follows exactly the curved casting axis 11 in this region. In order to achieve
this, the guiding device 63 e.g. comprises two U-shaped guiding elements 64, 66, which
are fixed to a bottom plate 67 of the mould housing 24, symmetrically with regard
to the vertical casting plane. Each of these U-shaped guiding elements 64, 66 includes
a curved guiding channel; i.e. a channel delimited by two cylindrical guiding surfaces
64', 64", respectively 66', 66", and a plane base surface 64"', 66"'. It will be noted
that the two cylindrical guiding surfaces 64', 64", respectively 66', 66", have their
axis of revolution perpendicular to the casting plane (plane A-A) and passing through
the centre of the circular segment that represents the casting axis 11 in this region.
In each of the two guiding channels is received a guided element 68, 70 that is rigidly
secured to the mould tube 12 and guided in the curved guiding channel of the respective
guiding element 64, 66 by the cylindrical guiding surfaces 64', 64", respectively
66', 66" (i.e. the cylindrical guiding surfaces 64', 64", 66', 66" fix all translational
and rotational degrees of freedom of the lower end of the mould tube). In other words,
the curved lateral guiding surfaces 64', 64", respectively 66', 66", are designed
so as to impose, via the guided elements 68, 70, an oscillation path with a curvature
corresponding essentially to the curvature of the curved casting axis 11 on the lower
end of the copper tube 14. This means that the oscillation path of the lower end of
the copper tube 14 exactly follows the curved casting axis 11.
[0023] As best shown in Fig. 3, the guided elements 68, 70 are supported by a ring element
72 that surrounds the lower end of the copper tube 12. As best shown in Fig. 1 and
Fig. 2, this ring element 72 is fixed to the copper tube 12 by means of gibs 74 engaging
grooves in the wall of the copper tube 14. It will be noted that the guiding elements
64, 66 and the guided elements 68, 70 are designed so that a continuous flow of cooling
water streaming out of the bottom end of the mould housing 24 cools these elements
64, 66, 68, 70. Schematic spray nozzles 76 indicate that the guiding device 63 is
also subjected to a forced cooling from the underside.
[0024] Referring now to Fig. 1 and Fig. 3, it will further be noted that the ring element
72 is arranged in a central cut-out of the bottom plate 67, wherein a radial gap,
which subsists between the ring 72 and the bottom plate 67, is sealed by a sealing
element, preferably a graphite seal 78.
[0025] When the two annular pressure chambers 40, 42 are alternately pressurised and depressurised,
the annular cylinder 30 imposes an oscillating movement on the mould tube 12. At the
height of the lower end of the copper tube 14, the guiding device 63 warrants that
the oscillations, which are imposed on the upper end of the mould tube 12, result
in oscillations of the lower end of the copper tube 14 that strictly follow the curved
casting axis 11. In other words, the guiding device 63 warrants that the copper tube
14 does not exert significant lateral forces on the curved strand leaving the mould
tube 12. At the upper end of the mould tube 12, the oscillation path is, at least
in the device described above, not completely identical to the casting axis 11. This
difference in the oscillation paths of the lower and upper end of the mould tube 12
becomes possible because the copper tube 14 is not a very rigid body and can therefore
be easily subjected to small oscillatory deformations, which compensate differences
in the oscillation paths. These oscillatory deformations, which mainly take place
in the upper mould tube 12, do not significantly affect the quality of the cast product,
because the liquid steel level, indicated by arrow 79 in Fig. 1 & 2, is located roughly
150 mm below the axis of rotation 54. Therefore, it is sufficient to warrant that
the stability of the copper tube 14 is not affected by these oscillatory deformations.
This is the reason why the annular cylinder 30 should advantageously have an axis
of rotation 54 as described above. It can indeed be shown that a possibility of rotation
about the axis 54 helps to reduce the deformations of the copper tube 14 by about
50 %. If a further reduction of the deformations of the copper tube 14 is required,
then it is e.g. possible to fix the annular cylinder 30 to the top end of the housing
24, respectively the support flange 16 of the mould 12 to the flange 36 of the inner
ring 34, so as to allow small linear displacements (size range generally less than
1 mm) parallel to the vertical casting plane and transversal to the casting axis 11
(see Fig. 1, arrow 80).
[0026] A continuous casting mould 10 of the type described above has meanwhile been successfully
tested. It is capable of producing oscillations with an amplitude from 1-20 mm and
frequencies up to 600 cycles per minute. It distinguishes itself not only by a very
high movement accuracy, but also by a low lubricant consumption, a very compact and
simple layout, a quick copper tube exchange, a quick exchange of the oscillation device
in case of a breakdown of the latter, and low maintenance costs, because each component
may be very easily exchanged.
1. A continuous casting mould for a continuous steel casting machine with a curved casting
axis (11) in a vertical casting plane, comprising:
a mould tube (12) forming a curved casting channel (20) along said curved casting
axis (11), said mould tube (12) having an upper end and a lower end and a support
flange (16) at is upper end;
a mould housing (24) surrounding said mould tube (12), said mould housing (24) having
a top end and a bottom end;
a cooling system (26) within said mould housing (24) for cooling said mould tube (12);
and
a pneumatic or hydraulic actuator means (30) connected between said support flange
(16) of said mould tube (12) and said housing (24) for axially supporting and oscillating
said mould tube (12);
characterised
by a guiding device (63) that is connected directly between said lower end of said mould
tube (12) and said bottom end of said mould housing (24), said guiding device (63)
imposing a curved oscillation path on said lower end of said mould tube (12), wherein
said imposed oscillation path exactly follows said curved casting axis (11).
2. The continuous casting mould as claimed in claim 1, characterised in that said guiding device (63) comprises at least one guiding element, which is fixed to
said housing (24) and includes a curved guiding channel, and a guided element, which
is fixed to said mould tube (12) and guided in said curved guiding channel of said
at least one guiding element.
3. The continuous casting mould as claimed in claim 1 or 2, characterised in that said guiding device (63) is forcedly cooled.
4. The continuous casting mould as claimed in any one of claims 1 to 3, characterised in that said pneumatic or hydraulic actuator means, is an annular cylinder (30), which directly
surrounds said support flange (16) of said mould tube (12) and has a central cylinder
(30) axis that is substantially tangential to said curved oscillation path.
5. The continuous casting mould as claimed in claim 4, characterised in that said annular cylinder (30) is forcedly cooled.
6. The continuous casting mould as claimed in claim 4 or 5, characterised in that said upper end of said mould tube (12) is secured with functional play to said annular
cylinder (30).
7. The continuous casting mould as claimed in claim 4 or 5, characterised in that said upper end of said mould tube (12) is rigidly secured to said annular cylinder
(30).
8. The continuous casting mould as claimed in any one of claims 4 to 7, characterised in that said annular cylinder (30) is supported on said top end of said housing (24) so as
to be capable of oscillating about an axis of rotation (54) that is substantially
perpendicular to said vertical casting plane and intersects said curved oscillation
path.
9. The continuous casting mould as claimed in claim 8, characterised in that said annular cylinder (30) has two journals (46, 48), which are arranged so as to
define said axis of oscillation (54), and said top end of said housing (24) has two
bearings (50, 52), which receive said journals (46, 48).
10. The continuous casting mould as claimed in claim 8 or 9, characterised by a flexible annular sealing element arranged between said annular cylinder (30) and
said top end of said housing (24).
11. The continuous casting mould as claimed in any one of claims 4 to 10, said annular
cylinder (30) is fixed to said top end of said housing (24), so as to allow small
linear displacements parallel to said vertical casting plane and transversal to said
casting axis (11).
12. The continuous casting mould as claimed in any one of claims 4 to 11, characterised by
an annular gap between said support flange (16) and said annular cylinder (30), and
a refractory lining (60) in said annular gap.
13. The continuous casting mould as claimed in any one of claims 4 to 11, characterised by spray nozzles (62) spraying a cooling fluid on the underside of said annular cylinder
(30).
14. The continuous casting mould as claimed in any one of claims 1 to 13, characterised in that said cooling system is a spray cooling system (26).
15. The continuous casting mould as claimed in any one of claims 1 to 14, characterised by
a bottom plate (67) at said bottom end of said mould housing (24), said bottom plate
(67) having a central cut-out;
a ring element (72) fixed to said lower end of said mould tube (12), said ring element
(72) being arranged in said central cut-out of said bottom plate (67), wherein a radial
gap subsists between said ring element (72) and said bottom plate (67); and
a sealing element (68) sealing said radial gap.
1. Stranggießkokille für eine Stahl-Stranggießmaschine mit einer in einer vertikalen
Gießebene gekrümmten Gießachse (11), umfassend:
ein Kokillenrohr (12), das einen gekrümmten Gießkanal (20) entlang der gekrümmten
Gießachse (11) bildet, wobei das Kokillenrohr (12) ein oberes Ende, ein unteres Ende
und einen Stützflansch (16) an seinem oberen Ende aufweist;
ein Kokillengehäuse (24), das das Kokillenrohr (12) umschließt, wobei das Kokillengehäuse
(24) ein oberes Ende und ein unteres Ende aufweist; ein Kühlsystem (26) innerhalb
des Kokillengehäuses (24), um das Kokillenrohr (12) zu kühlen; und
ein pneumatisches oder hydraulisches Betätigungsmittel (30), das zwischen dem Stützflansch
(16) des Kokillenrohrs (12) und dem Gehäuse (24) angeschlossen ist, um das Kokillenrohr
(12) axial zu stützen und in Oszillation zu versetzen;
gekennzeichnet durch
eine Führungsvorrichtung (63), die direkt zwischen dem unteren Ende des Kokillenrohrs
(12) und dem unteren Ende des Kokillengehäuses (24) angeschlossen ist, wobei die Führungsvorrichtung
(63) einen gekrümmten Oszillationsweg am unteren Ende des Kokillenrohrs (12) erzwingt,
wobei der erzwungene Oszillationsweg exakt der gekrümmten Gießachse (11) folgt.
2. Stranggießkokille nach Anspruch 1, dadurch gekennzeichnet, dass die Führungsvorrichtung (63) zumindest ein Führungselement, das am Gehäuse (24) befestigt
ist und einen gekrümmten Führungskanal einschließt, und ein geführtes Element, das
am Kokillenrohr (12) befestigt ist und im gekrümmten Führungskanal des zumindest einen
Führungselements geführt wird, umfasst.
3. Stranggießkokille nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass die Führungsvorrichtung (63) zwangsgekühlt wird.
4. Stranggießkokille nach irgendeinem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass das pneumatische oder hydraulische Betätigungsmittel ein Ringzylinder (30) ist, der
den Stützflansch (16) des Kokillenrohrs (12) direkt umschließt und eine Zylindermittelachse
aufweist, die im Wesentlichen tangential zum gekrümmten Oszillationsweg ist.
5. Stranggießkokille nach Anspruch 4, dadurch gekennzeichnet, dass der Ringzylinder (30) zwangsgekühlt wird.
6. Stranggießkokille nach Anspruch 4 oder 5, dadurch gekennzeichnet, dass das obere Ende des Kokillenrohrs (12) mit funktionsgerechtem Spielraum am Ringzylinder
(30) befestigt ist.
7. Stranggießkokille nach Anspruch 4 oder 5, dadurch gekennzeichnet, dass das obere Ende des Kokillenrohrs (12) starr am Ringzylinder (30) befestigt ist.
8. Stranggießkokille nach irgendeinem der Ansprüche 4 bis 7, dadurch gekennzeichnet, dass der Ringzylinder (30) am oberen Ende des Gehäuses (24) gestützt wird, um so um eine
Rotationsachse (54) oszillieren zu können, die im Wesentlichen senkrecht zur vertikalen
Gießebene steht und den gekrümmten Oszillationsweg schneidet.
9. Stranggießkokille nach Anspruch 8, dadurch gekennzeichnet, dass der Ringzylinder (30) zwei Zapfen (46, 48) aufweist, die so angeordnet sind, dass
sie eine Oszillationsachse (54) definieren; und dass das obere Ende des Gehäuses (24)
zwei Lager (50, 52) aufweist, die die Zapfen (46, 48) aufnehmen.
10. Stranggießkokille nach Anspruch 8 oder 9, gekennzeichnet durch ein flexibles ringförmiges Dichtelement, das zwischen dem Ringzylinder (30) und dem
oberen Ende des Gehäuses (24) angeordnet ist.
11. Stranggießkokille nach irgendeinem der Ansprüche 4 bis 10, wobei der Ringzylinder
(30) am oberen Ende des Gehäuses (24) befestigt ist, um so kleine lineare Verschiebungen
parallel zur vertikalen Gießebene und transversal zur Gießachse (11) zu erlauben.
12. Stranggießkokille nach irgendeinem der Ansprüche 4 bis 11, gekennzeichnet durch
einen Ringspalt zwischen dem Stützflansch (16) und dem Ringzylinder (30); und
eine feuerfeste Auskleidung (60) im Ringspalt.
13. Stranggießkokille nach irgendeinem der Ansprüche 4 bis 11, gekennzeichnet durch Sprühdüsen (62), die die Unterseite des Ringzylinders (30) mit einer Kühlflüssigkeit
besprühen.
14. Stranggießkokille nach irgendeinem der Ansprüche 1 bis 13, dadurch gekennzeichnet, dass das Kühlsystem ein Sprühkühlsystem (26) ist.
15. Stranggießkokille nach irgendeinem der Ansprüche 1 bis 14, gekennzeichnet durch
eine Bodenplatte (67) am unteren Ende des Kokillengehäuses (24), wobei die Bodenplatte
(67) einen mittigen Ausschnitt aufweist;
ein Ringelement (72), das am unteren Ende des Kokillenrohrs (12) befestigt ist, wobei
das Ringelement (72) im mittigen Ausschnitt der Bodenplatte (67) angeordnet ist, wobei
zwischen dem Ringelement (72) und der Bodenplatte (67) ein Radialspalt besteht; und
ein Dichtelement (68), das den Radialspalt abdichtet.
1. Moule de coulée continue pour une machine de coulée continue d'acier avec un axe de
coulée incurvé (11) dans un plan de coulée vertical, comprenant :
un tube de moule (12) formant un canal de coulée incurvé (20) le long dudit axe de
coulée incurvé (11), ledit tube de moule (12) possédant une extrémité supérieure et
une extrémité inférieure et une bride de support (16) à son extrémité supérieure;
un corps de moule (24) entourant ledit tube de moule (12), ledit corps de moule (24)
possédant une extrémité haute et une extrémité basse;
un système de refroidissement (26) à l'intérieur dudit corps de moule (24) pour refroidir
ledit tube de moule (12); et
un moyen d'actionnement pneumatique ou hydraulique (30) raccordé entre ladite bride
de support (16) dudit tube de moule (12) et ledit corps (24) pour supporter et osciller
axialement ledit tube de moule (12);
caractérisé
par un dispositif de guidage (63) qui est raccordé directement entre ladite extrémité
inférieure dudit tube de moule (12) et ladite extrémité basse dudit corps de moule
(24), ledit dispositif de guidage (63) imposant une trajectoire d'oscillation incurvée
sur ladite extrémité inférieure dudit tube de moule (12), dans lequel ladite trajectoire
d'oscillation imposée suit exactement ledit axe de coulée incurvé (11).
2. Moule de coulée continue selon la revendication 1, caractérisé en ce que ledit dispositif de guidage (63) comprend au moins un élément de guidage, qui est
fixé audit corps (24) et inclut un canal de guidage incurvé, et un élément guidé,
qui est fixé audit tube de moule (12) et est guidé dans ledit canal de guidage incurvé
dudit au moins un élément de guidage.
3. Moule de coulée continue selon la revendication 1 ou 2, caractérisé en ce que ledit dispositif de guidage (63) est refroidi de manière forcée.
4. Moule de coulée continue selon l'une quelconque des revendications 1 à 3, caractérisé en ce que ledit moyen d'actionnement pneumatique ou hydraulique est un vérin annulaire (30),
qui entoure directement ladite bride de support (16) dudit tube de moule (12) et possède
un axe central de vérin (30) qui est substantiellement tangentiel à ladite trajectoire
d'oscillation incurvée.
5. Moule de coulée continue selon la revendication 4, caractérisé en ce que ledit vérin annulaire (30) est refroidi de façon forcée.
6. Moule de coulée continue selon la revendication 4 ou 5, caractérisé en ce que ladite extrémité supérieure dudit tube de moule (12) est fixée avec un jeu fonctionnel
audit vérin annulaire (30).
7. Moule de coulée continue selon la revendication 4 ou 5, caractérisé en ce que ladite extrémité supérieure dudit tube de moule (12) est fixée rigidement audit vérin
annulaire (30).
8. Moule de coulée continue selon l'une quelconque des revendications 4 à 7, caractérisé en ce que ledit vérin annulaire (30) est supporté sur ladite extrémité haute dudit corps (24)
de façon à être capable d'osciller autour d'un axe de rotation (54) qui est substantiellement
perpendiculaire audit plan de coulée vertical et coupe ladite trajectoire d'oscillation
incurvée.
9. Moule de coulée continue selon la revendication 8, caractérisé en ce que ledit vérin annulaire (30) possède deux tourillons (46, 48) qui sont agencés de façon
à définir ledit axe d'oscillation (54), et ladite extrémité haute dudit corps (24)
possède deux paliers (50, 52) qui reçoivent lesdits tourillons (46, 48).
10. Moule de coulée continue selon la revendication 8 ou 9, caractérisé par un élément d'étanchéité annulaire souple agencé entre ledit vérin annulaire (30)
et ladite extrémité haute dudit corps (24).
11. Moule de coulée continue selon l'une quelconque des revendications 4 à 10, dans lequel
ledit vérin annulaire (30) est fixé à ladite extrémité haute dudit corps (24) de façon
à permettre de petits déplacements linéaires parallèles audit plan de coulée vertical
et transversaux audit axe de coulée (11).
12. Moule de coulée continue selon l'une quelconque des revendications 4 à 11, caractérisé par
un espace annulaire entre ladite bride (16) et ledit vérin annulaire (30), et
une chemise réfractaire (60) dans ledit espace annulaire.
13. Moule de coulée continue selon l'une quelconque des revendications 4 à 11, caractérisé par des buses de pulvérisation (62) pulvérisant un fluide de refroidissement sur la face
inférieure dudit vérin annulaire (30).
14. Moule de coulée continue selon l'une quelconque des revendications 1 à 13, caractérisé en ce que ledit système de refroidissement est un système de refroidissement par pulvérisation
(26).
15. Moule de coulée continue selon l'une quelconque des revendications 1 à 14, caractérisé par
une plaque de fond (67) à ladite extrémité basse dudit corps de moule (24), ladite
plaque de fond (67) possédant une découpe centrale;
un élément annulaire (72) fixé à ladite extrémité inférieure dudit tube de moule
(12), ledit élément annulaire (72) étant agencé dans ladite découpe centrale de ladite
plaque de fond (67), dans lequel un espace radial subsiste entre ledit élément annulaire
(72) et ladite plaque de fond (67); et
un élément d'étanchéité (68) obturant ledit espace radial.