Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
COI~TIN~oUS CAS~ING WITHDRA~7A~ APPA~ATUS
The present invention relate~ to metal cà~ting plants
and more particularly to apparatu~ for withdrawing a cas-
ting from a mould.
The invention may be used in,metallurgy industry in
continuous metal casting plants wherein a continuously
fo~med casting i9 withdrawn from the mould horizontally
or at a certain inclination to the horizontal plane.
Enown to the prior art are apparatu~ for continuou~
metal casting (cf. the boo~ "Horizontal Continuous Casting
of Nonferrous Metals and Alloys" b~ Shatagin O.A., Sladko-
shteev V.P., et al, Moscow, Publishing House "Metallurgia'1,
1974~ p..p. 27-28~ 31 - 33~ in Russian). In cont$nuous me-
tal casting plants castings are withdrawn from the mould
with the aid of roller racks or with the aid of shoes
pre~sed against the caeting to be withdrawn.
Construction of such apparatus fail~ to provide a pre-
cise control over the process of withdrawing the casting
from the mould, i.e., fail~ to provide a rapid and reliable
withdrawal of the casting ~rom the mould.
Known to the prlor art is an apparatus (cf. Great
Britain Patent No.1,522,110, Int. Cl. B 22 d 11/28, 1978)
for withdrawing a caBting from the mould, comprising a mo-
vable housing with movable shoes, each of which is a880cia-
ted with the housing through an intermediate rod. The rod
is preloaded by springs and ~ith respect to the hous$ng
may move parallel to the axis of the ca~ting. For adju~ting
f;
the force of the springs, provision is made for a
ring. When the apparatus housing is moved in the
direction of movement of the casting the housing
causes wedges secured in the housing to jam rollers,
As a result, the rollers press the shoes against the
casting and the latter is gripped thereby. When the
housing is moved in the reverse direction the rollers
are released under the action of the springs and the
shoes are free to return to the initial position.
Thereafter the apparatus is ready to repeat the cycle
of step by step withdrawal of the casting.
Construction of the apparatus provides only
a small contacting area between the shoes and the cast-
ing, has a complicated kinematics of the shoes, fails
to ensure a precise control over the casing withdrawal
process and also to combine the performance of two
functions: withdrawal and intensive cooling of the
casting.
It is an object of the present invention to
provide an apparatus for withdrawing a casting from a
mould, ensuring a rapid and reliable withdrawal of the
casting from the mould.
It is another object of the invention to
provide an intensive cooling of the casting in the zone
of secondary cooling.
In accordance with a particular embodiment
of the invention there is provided an apparatus for
withdrawing a casting from a mould of a continuous
metal casting plant. The apparatus includes a movable
housing and cooled shoes disposed along the perimeter
-- 3 --
of the casting, Two pairs of wedges are disposed
between each shoe and the housing, one wedge of
each pair of wedges being rigidly secured on the
shoe, the other wedge of the pair being disposed
in a recess in the housing for movement relative to
the housing and the one wedge. A member adjustable
in length connects the other wedges of each of the
two pairs of wedges with each other. Means are
included for withdrawing the casting from the mould,
the withdrawing means including hydraulic cylinders
with rods for withdrawing the casting from the mould,
Means are also provided for pressing the shoes
against the casting, the pressing means including
hydraulic cylinders with rods for pressing the shoes
against the casting, A crossbar is connected with the
rods of the means for withdrawing the casting from
the mould and the means for pressing the shoes against
the casting, and a member of a constant length con-
nects the other wedges with the crossbar.
The apparatus may suitably be provided with
mechanism for moving the cooled shoes in the direction
perpendicular to the direction of movement of the
casting the number of which corresponds to the number
of pairs of the wedges and each of which comprises a
rod having a spring and installed on the wedge rigidly
secured on the shoe, and a bushing accommodating the
rod adapted to be moved in the direction perpendi-
cular to the direction of movement of the casting.
The invention will now be described in
detail with reference to the accompanying drawing
illustrating a general view of an apparatus
for withdrawing a casting from
' f 7
--4--
the mould o~ a continous metal ca~ting plant, according
to the invention. - -
An apparatus for withdrawing a casting from a mouldduring thc continuous casting of metals comprises a mova-
ble housing 1, cooled ~hoes 2 encompassing almost the en-
tire ~urface (appro~imately 95~) of a casting 3 along the
perimeter thereof. The length of the shoe 2 corresponds
to or may e~ceed the length of the withdrawal step of the
casting 3. The cooled shoes 2 are internally disposed in
the hou~ing 1 made in the ~orm of a tube and provided
with rece~ses 4 and openings 5. Each shoe 2 is provided
with two pairs of wedges 6, 7 contacting each other. Each
of the wedges 6 of each pair is stationary and i~ rigidly
secured on the shoe 2, whlle the other, movable wedges 7,
are disposed in the recesses 4 of the housing 1 and may
be moved in the recesses 4 relative to the housing 1 and
the stationar~ wedges 6.
The mo~able wedges 7 are connected with each other
through a member 8 ad~ustable in length and one of them
also with a movable crossbar 9 through a member 10 of a
¢onstant length.
The member 8 is ad~usted in length through the openings
5 of the hou~ng 1, with the aid of a sleeve 11 operating
on the ~crew-and-nut principle. Each opening 5 in the hou-
sing 1 i9 made oppo~ite the sleeve 11.
.
1~7~'~ `7~7
The cro~sbar 9 i9 connected to rods 12 of Fower hyd-
raulic cylinders of a drive for withdrawing the casting 3
f~om the mould (the hydraulic cylinders and the mould are
not shown-in the drawing) and to rods 13 of a hydraulic
drive 14 for pressing the shoes 2 against the casting 3.
Relative to the end face of the housing 1, the cro~s-
bar 9 is installed at a distance being not less than the ma-
ximum possible travel of the movable wedges 7 in relation
to the stationary wedges 6. The travel of the wedges 7 cor-
responds to the travel of the roas 13 of the hydraulic
drive 14. ~he hydraulic drives 14 are secured on the hou-
sing 1 of the apparatus.
The shoes 2 are kept constantly pressed against the
housing 1 through the pairs of the wedges 6 and 7 by means
of a mechanism 15 for moving the cooled shoes 2 in the
direction perpendicular to the direction of movement Or
the casting 3.
~ he mechani~m 15 for moving the cooled shoe~ 2 is made
in the form of a rod 16 having a sprin~ 17 and installed
on the stationary YJedge 6 and in a guide bush1ng lB in
which the rod 16 is moved in the direction perpendicular
to the direction of movement of the casting 3. For adjusting
the force of the springs 17, provision is made for a nut 19.
The ~ushing~ 18 are arranged in the housing 1 in circu-
lar openings on the side of the cros~bar 9, while at the
opposite end of the housing 1 they are arranged in recesses
20 80 as not di~turb the alignment of the housing 1 and the
1.~'7~t~f7~7
-6-
shoes 2 with the casting 3 at the moment when heating or
cooling of the shoeq 2 takes place, as at this moment the
linear dimensions of the shoes 2 are changing.
The nu~ber of the mechanisms 15 equals the number of
pairs of the wedges 6 and 7.
~ ounted on the end of the housing 1, opposite to the
crossbar 9, is a two-chamber manifold 21 provided with a
system of pipelines 22 fof delivering the coolant to and
discharging it from each shoe 2.
The housing 1 of the apparatus i~ installed on rollers
23 and vrhen the casting 3 is being withdra~n, the housing
is moved along guides 24.
The apparat U8 for withdrawing the casting 3 from the
mould during the continuous casting of metal operates in the
following way.
The shoes 2 are kept constantly pressed against the
housing 1 through the pairs of the wedges 6 and 7 by means
of the mechanisms 15 for movlng the cooled shoes 2 in the
direction perpendicular to the direction of movement of the
casting 3. The pressure exerted on the shoes 2 is accom-
plished by the rods 16 preloaded by the springs 17.
~ irst to be cut into operation is the cooling system
of the shoe~ 2 together ~ith the manifold 21 and the system
of the pipelines 22. Then follows the preliminary clamping
of the casting 3.
~ en the drives 14 are act~ ted, their rod~ 13 connec-
ted with the cross~ar 9 put the crossbar 9 in motion. Over-
1~ J'~'7f~7
~7-
coming the force of the ~prings 17 of the mechanism 15 for
moving the cooled shoes 2, the crossba-r 9 acting through
the members 8 and 10 moves the wedges 7 relative to the
v~edges 6 for a preset step sufficient for pressing the
shoes 2 to the ca~ting 3; as a result, the ~hoes 2 tightly
clamp the casting 3 with a unifoim pressure exerted along
the entire length due to the uniform movement of the wed-
ges 7 over the wedges 6.
Then the hydraulic cylinders of the drive for withdra-
wing the casting 3 from the mould are cut into operation
and acting throug~ the rods 12, 13 thereof and the movable
cros~bar 9 withdraw the casting 3 from the mould for the
preset length while the cooled shoes 2 provide an additio-
nal cooling of the casting.
The ~ithdrawal apparatu~ is returned to the inital
position by reversing the hydraulic cylinders of the drive
for v~ithdrav~ing the casting 3, the shoes 2 being prelimina-
rily unclamped by the hydraulic drives 14 acting through
the crossbar 9, the members 8 and 10, and the wedges 6 and 7.
~ hen the cycle is repeated.
Duration of the pause between the cycles of ~ithdra-
wing ths ¢asting 3 depends on the time o~ forming the
casting 3 in the mould.
I~ it i8 required to provide an intensivs cooling of
the casting 3, the shoes 2 are brought in contact w~th the
casting 3 immediately after the spparatus has been returned
to the init i81 position.
-8-
Due to the changed kinematics of the shoes 2, the
proposed invention makes it possible to eliminate any da-
mage to the surface o~ the casting 3 when the latter is
withdra~n from the mould and during the idle movement of
the appsratua to the initial position.
Due to a clearly defined division of the functions re-
lating to clamping and withdrawing between the two drives,
the invention guarantee~ the withdrawal of the casting 3
for a preset withdrawal step without any slip o~ the shoes 2
relative to the casting 3. Besides, in pauses between the
cycles of withdrawing the casting 3 from the mould, the
drive for withdrawing the casting 3 is used ror perfor-
ming additional operations, for example, for pressing the
face portion of the skin of the casting 3 being iormed in
the mould to a member for providing ~n additional remo~al
o~ heat from this face surface which further will contribu-
te to a decrease in the fo~ce exerted for dividing the
casting 3 into cut-to-length section~.
The reliable regulation of pressing the shoes 2 against
the casting 3 effected with the aid of the mechanisms 15
for moving the shoes 2 in the direction perpendicular to
the direction of movement of the casting 3 and owing to the
pairs of the wedges ~ and 7 provides the uniform removal of
heat and uni~orm growth of the ~kin along the entire peri-
meter of the casting 3 which eliminates distortion o~ the
geometry of the.casti~g 3 and improves the ~uality thereo~.
~ l r~ ~ ~7 ~
The proposed in~ention allows the method of a horizontal
continuous casting of the castings 3, for e~ample, from alu-
minium alloys, to be effected, thereby making it possible
to improve the quality Or the castings 3, increase the me-
tal yield by 3-5% and also to step up the rate of cssting
by 3 to 6 times (depending upon the cross-section area of
a casting).
