Title of Invention

CHILL-CASTING TUBE

Abstract A chill-casting tube having a double T-shaped inner and outer cross section in the beam-blank format, which is encased by a water jacket (12) matched to its outer contour, forming a water gap (14), characterized in that the wall thickness (D) of the chill casting tube (1) in the rounded transition regions (2, 2a, 2b, 2c, 2d) from the mutually frontally opposite central lands (4), drawn in towards the longitudinal axis (3), to the adjacent oblique flanges (5) is dimensioned at least partially to be smaller than in the remaining wall sections (6, 7).
Full Text The invention generally relates to a chill-casting tube having a double T-
shaped inner and outer cross section in the beam-blank format.
The invention particularly relates to a chill-casting tube having a double T-
shaped inner and outer cross section in the beam-blank format, which is encased
by a water jacket matched to its outer contour, forming a water gap.
During the continuous casting of metals with a chill-
casting tube, the material temperatures in the chill-
casting wall result from the thermal loadings occurring
during continuous casting and the cooling conditions
arising from the respective cooling medium, which as a
rule flows from bottom to top in the form of water in a
water gap between a water jacket matched to the outer
contour of the chill-casting tube and the outer surface
of the chill-casting tube, in the process picks up the
heat which arises and transports it away. The
dissipation of the heat by means of cooling water is
largely determined by the water velocity in the water
gap.
During the continuous casting of metals with a chill-
casting tube of the generic type under discussion, it
has been observed that, because of the specific
geometry of the bean-blank format, extreme local heat
stresses occur in the transition regions of the
mutually frontally opposite central lands, drawn in
towards the longitudinal axis, to the adjacent: oblique
flanges. In the event of unfavourable geometric
conditions of the transition regions,these local heat
stresses lead to overheating of the chill-casting tube
and consequently to a drastic reduction in its service
life.
On the basis of the prior art, the invention is based
on the object of providing a chill-casting tube having
a double T-shaped inner and outer cross section in the
beam-blank format for the continuous casting of metals in which local
overheating of the transition regions is avoided and, as a result, a longer
service life is achieved.
Accordingly, the present invention provides a chill-casting tube having a
double T-shaped inner and outer cross section in the beam-blank format,
which is encased by a water jacket matched to its outer contour, forming a
water gap, characterized in that the wall thickness of the chill casting tube in
the rounded transition regions from the mutually frontally opposite central
lands, drawn in towards the longitudinal axis, to the adjacent oblique flanges
is dimensioned at least partially to be smaller than in the remaining wall
sections.
Preferably, the wall thickness in the transition regions is reduced only in the
vertical range of the bath level.
Preferably, longitudinally directed trough-like cutouts are provided on the
outside of the transition regions.
Preferably, a plurality of longitudinally directed grooves running beside one
another are provided on the outside of the transition regions.
Preferably, a plurality of longitudinally directed holes running beside one
another are provided in the wall sections of the transition regions.
Preferably, the water jacket has a substantially rectangular cross section and
filling pieces matched to the cross sectional area formed by the outer contour
of the chill-casting tube and the inner contour of the water jacket are
introduced between the water jacket and the lands or the flanges.
As a result of the at least partial reduction in the
wall thickness of the chill-casting tube in the rounded
transition regions, considerably improved heat
dissipation is achieved here, therefore local
overheating of the transition regions is avoided and,
consequently, the service life of the chill-casting
tube is increased considerably.
In view of the fact that, during the continuous casting
of metals, the highest thermal stress in the chill-
casting tube generally occurs in the vertical range of
the bath level,
the wall thickness is----reduced in the transition
regions only in the vertical range of the bath level.
The reduction of the wall thickness of the chill-
casting tube in the rounded transition regions can be
carried out in various ways.
On---------------------------------------------the
outside of the transition regions, longitudinally
directed trough-like cutouts are provided. The
curvature of the cutouts can in this case be matched to
a great extent to the curvature of the inner surface of
the transition regions. In addition, the wall-thickness
reduction in the form of trough-like cutouts has the
advantage that the outer surface of the chill-casting
tube is increased, so that a still better cooling
effect can be achieved.,
A further possible way of reducing the wall thickness
is seen in the features of the present invention
wherein a plurality of longitudinally directed
grooves running beside one another are provided on the
outside of the transition regions. The cross section
and/or the depth of the grooves can be dimensioned to
be the same in each transition region or different. The
cross section of the grooves can be rounded or angular,
for example triangular.
Furthermore, corresponding to the features of the
invention, it is conceivable that, in order to reduce the
wall thickness in the wall sections of the transition
regions, a plurality of longitudinally directed holes
running beside one another are provided. The size of
the holes, their number, their spacing from one another
and also their position in relation to the outer and
inner contour of the chill-casting tube can vary.
However, it is advantageous if the holes are in closer
proximity to the outer surface than to the inner
surface of the chill-casting tube.
Since the dissipation of the heat by means of cooling
water - as is known - is determined by the water
velocity in the water gap between the chill-casting
tube and the water jacket, this water gap should be
maintained even in the area of the wall-thickness
reduction, in order to guarantee a uniform water
velocity in the entire water gap. To this extent, the
embodiment according to the features of the invention
provides for the water jacket to have a rectangular
cross section and for filling pieces matched to the
cross-sectional area formed by the outer contour of the
chill-casting tube and the inner contour of the water
jacket to be inserted between the water jacket and the
lands or the flanges.
The invention is explained in more detail below using exemplary
embodiments which are illustrated in the accompanying drawings and in which :
The invention is explained in more detail below using
exemplary embodiments which are illustrated in the
drawings and in which:
Figure 1 shows, in a schematic perspective, a chill-
casting tube in the beam-blank format without
a water jacket but with lateral filling
pieces;
Figure 2 shows, likewise in a schematic perspective,
the chill-casting tube of Figure 1 with a
filling piece illustrated separately;
Figure 3 shows a plan view of a chill-casting tube
without a sealing cover in the area of the
lateral channels, but without a water jacket,
and
Figure 4 shows a plan view of a chill-casting tube
according to further embodiments, without a
sealing cover and water jacket.
In Figures 1 to 4, 1 designates a chill-casting tube
having a double T-shaped inner and outer cross section
in the beam-blank format. The chill-casting tube 1 is
used for the continuous casting of metals. In Figures 3
and 4, the curvature of the chill-casting tube 1 in the
longitudinal direction is not illustrated.
As can be seen in more detail from Figure 3, the wall
thickness D of the chill-casting tube 1 in the rounded
transition regions 2 from the mutually frontally
opposite central lands 4 drawn in towards the
longitudinal axis 3 to the adjacent oblique flanges 5
is dimensioned to be smaller than the wall thickness Dl
in the remaining wall sections 6 and 7.
In the embodiment of Figures 1 to 3, the reduction in
the wall thickness is carried out by longitudinally
directed trough-like cutouts 8 being provided on the
outside of the transition regions 2. As can be seen
from Figure 2, these cutouts 8 extend only in the
vertical range of the bath level, not specifically
illustrated. The curvature 9 'of the cutouts 8 is
largely matched to the curvature 10 of the inner
surface 11 of the chill-casting tube 1 in the
transition regions 2.
On the circumference of the chill-casting tube 1 there
is a water jacket 12, which can be seen only from
Figure 3, having a substantially rectangular cross
section. Formed between the water jacket 12 and the
outer surface 13 of the chill-casting tube 1 is a water
gap 14, through which cooling water is led from bottom
to top at a predetermined water velocity.
In order that a uniform water velocity is also achieved
in the water gap 14 in the lateral channels 15 of the
chill-casting tube 1 which, according to Figures 1 and
2, are closed at the upper end by sealing covers 16,
these channels 15 are provided with filling pieces 17
which, in the upper regxon, are also matched to the
trough-like cutouts 8.
Figure 4 illustrates four different embodiments
relating to how the wall-thickness reduction of the
chill-casting tube 1 can also further be implemented.
In the transition regions 2a, 2b, 2c, a plurality of
longitudinally directed grooves 18, 18a, 18b running
beside one another are provided on the outside. While
in the transition region 2a the grooves 18 have a
triangular cross section, the grooves 18a, 18b in the
transition regions 2b, 2c have rounded bases. In this
case, the grooves 18b in the transition region 2c have
a greater depth than the grooves 18a in the transition
region 2b.
In the transition region 2d, the wall-thickness
reduction is implemented by means of holes 19. These
holes 19 lie closer to the outer surface 13 of the
chill-casting tube 1 than to the inner surface 11.
Both the grooves 18, 13a, 18b and the holes 19, like
the cutouts 8, extend only in the vertical range of the
bath level.
List of reference symbols
1 - Chill-casting tubs
2 - Transition regions
2a - Transition region
2b - Transition region
2c - Transition region
2d - Transition region
3 - Longitudinal axis of 1
4 - Lands
5 - Flanges
6 - Wall sections of 1
7 - Wall sections of 1
8 - Cutouts in 2
9 - Curvature of 3
10 - Curvature of 2
11 - Inner surface of 1
12 - Water jacket
13 - Outer surface of 1
14 - Water gap
15 - Channels
16 - Sealing cover
17 - Filling pieces
18 - Grooves in 2a
18a - Grooves in 2b
18b - Grooves in 2c
19 - Holes in 2d
D - Wall thickness of 1 in 2
Dl - Wall thickness of 1 in 6, 7
WE CLAIM :
1. A chill-casting tube having a double T-shaped inner and outer cross
section in the beam-blank format, which is encased by a water jacket (12)
matched to its outer contour, forming a water gap (14), characterized in that
the wall thickness (D) of the chill casting tube (1) in the rounded transition
regions (2, 2a, 2b, 2c, 2d) from the mutually frontally opposite central lands
(4), drawn in towards the longitudinal axis (3), to the adjacent oblique flanges
(5) is dimensioned at least partially to be smaller than in the remaining wall
sections (6, 7).
2. Chill-casting tube as claimed in claim 1, wherein the wall thickness (D)
in the transition regions (2, 2a, 2b, 2c, 2d) is reduced only in the vertical range
of the bath level.
3. Chill-casting tube as claimed in claim 1 or 2, wherein longitudinally
directed trough-like cutouts (8) are provided on the outside of the transition
regions (2).
4. Chill-casting tube as claimed in claim 1 or 2, wherein a plurality of
longitudinally directed grooves (18, 18a, 18b) running beside one another are
provided on the outside of the transition regions (2a, 2b, 2c).
5. Chill-casting tube as claimed in claim 1 or 2, wherein a plurality of
longitudinally directed holes (19) running beside one another are provided in
the wall sections of the transition regions (2d).
6. Chill-casting tube as claimed in claim 1 to 5, wherein the water jacket
(12) has a substantially rectangular cross section and filling pieces (17)
matched to the cross sectional area formed by the outer contour of the chill-
casting tube (1) and the inner contour of the water jacket (12) are introduced
between the water jacket (12) and the lands (4) or the flanges (5).
7. Chill-casting tube, substantially as herein described, particularly with
reference to and as illustrated in the accompanying drawings.

A chill-casting tube having a double T-shaped inner and outer cross section in the beam-blank format, which is encased by a water jacket (12) matched to its outer contour, forming a water gap (14), characterized in that the wall thickness (D) of the chill casting tube (1) in the rounded transition regions (2, 2a, 2b, 2c, 2d) from the mutually frontally opposite central lands (4), drawn in towards the longitudinal axis (3), to the adjacent oblique flanges (5) is dimensioned at least partially to be smaller than in the remaining wall sections (6, 7).

Documents:

702-cal-2002-abstract.pdf

702-cal-2002-claims.pdf

702-cal-2002-correspondence.pdf

702-cal-2002-description (complete).pdf

702-cal-2002-examination report.pdf

702-cal-2002-form 1.pdf

702-cal-2002-form 18.pdf

702-cal-2002-form 2.pdf

702-cal-2002-form 3.pdf

702-cal-2002-form 5.pdf

702-cal-2002-gpa.pdf

702-cal-2002-granted-abstract.pdf

702-cal-2002-granted-claims.pdf

702-cal-2002-granted-correspondence.pdf

702-cal-2002-granted-description (complete).pdf

702-cal-2002-granted-drawings.pdf

702-cal-2002-granted-examination report.pdf

702-cal-2002-granted-form 1.pdf

702-cal-2002-granted-form 18.pdf

702-cal-2002-granted-form 2.pdf

702-cal-2002-granted-form 3.pdf

702-cal-2002-granted-form 5.pdf

702-cal-2002-granted-gpa.pdf

702-cal-2002-granted-priority document.pdf

702-cal-2002-granted-reply to examination report.pdf

702-cal-2002-granted-specification.pdf

702-cal-2002-granted-translated copy of priority document.pdf

702-cal-2002-priority document.pdf

702-cal-2002-reply to examination report.pdf

702-cal-2002-specification.pdf

702-cal-2002-translated copy of priority document.pdf


Patent Number 235989
Indian Patent Application Number 702/CAL/2002
PG Journal Number 37/2009
Publication Date 11-Sep-2009
Grant Date 10-Sep-2009
Date of Filing 16-Dec-2002
Name of Patentee KM EUROPA METAL AKTIENGESELLSCHAFT
Applicant Address KLOSTERSTRASSE 29, D-49074 OSNABRUCK
Inventors:
# Inventor's Name Inventor's Address
1 EICHHOLZ-BOLDT RAIMUND FRIESENHOF 26, D-49078 OSNABRUCK
2 HAURI ROLAND NIEDER WEG 57, CH-8907, WETTSWIL
3 KOLBECK DIETMAR KATHARINENSTRASSE 12, D-49439 STEINFELD
4 HUGENSCHUTT GERHARD ENGTER STRASSE 118, D-49191 BELM
PCT International Classification Number B22D 11/055
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102 03 967.4 2002-01-31 Germany