Title of Invention

"PLATE CHANGE DRAWER FOR A METALLURGICAL VESSEL AND SET OF PLATES FOR THIS DRAWER"

Abstract Plate change drawer for a metallurgical vessel such as a contin¬uous caiting distributor (2). The drawer has a chassis (12) mounted under the metallurgical vessel, at least one fixed upper plate (18) and at least one replaceable lower plate34 (22), means(24)of applying pres¬sure to force the lower plat (22) against the fixed plate, the chas- eifi (12) having guide means for receiving a lower replacement plate -  " » (22) alongside the lower plate (22) during pouring, and actuation means .for bringing the lower replacement plate (22) in place of the plate daring pouring.  The upper fixed plate (18) and the lower re- placeable plate (22) have identical polygonal peripheries and are offset angularly so that they do not overlap completely. The poly¬gonal periphery of the plates is a square or a square with rounded comers.
Full Text The invention concerns & plate change drawer for a metallurgical vessel such as & continuous oastiag distributor -, the drawer has a chassis mounted under the metallurgical vessel, at least one fixed upper plate and at least one replacable lower plate, pressure means for applying the lower plate against the fixed plate, the chassis having means of guidance for receiving a lower replacement plats
alongside the lower plate during casting and actuation means for cringing the lower replacement plate in the place of the plate during casting.
In the continuous casting of steel the metal is transfered into successive veaaelii such as ladles and distributors. One or nor a pouring holes are provided in the bottom of each container for cast* ing the metal.
The flow can he regulated by different means such as plate clos¬ures, stopper rods or simply a calibrated noaale,
Some applications call for protection of the molten metal from the surrounding air. A refractory jet protection tube is then fasten¬ed under the vessel to surround the jet as it emerges from the pouring hole.
Whatever the to of pouring refraotory used, these refractories wear out and have to be changed so that the casting can be continued with the same vessel.

Various solutions are already known for exchanging refractories without Interruptiag the pouring.for example., Belgian Fatant No. 214,385 describee a tube changing device. In a device of this type the taphole is terminated by a fixed plate. A lower plate combined with a Jet protection tube is laid against the fixed plate to assure a tight joint. When this plate and the Jet protection tube associated
r with it have to be replaced, the plate of a new plate/tube assembly .is placed alongside the plate to be changed and puahed by-adequate means. The new plate expels the worn.plate and takes its place.
To aaaure a perfect alignment of the upper face of the lower plate with the lowor face of the upper plate, the fixed upper plate is gen¬erally longer than the lower plate at least on the aide of introduct¬ion of the replacement plate so that the new plate can be introduced against the end of the upper plate when the plate to be replaced is still in the pouring position.
These plates are frequently surrounded With a metal envelope. The use of a metal envelope makes it possible to obtain a plate ready for use, the outside dimensions of which are well-defined and which has resistant integrated sliding and support surfaces. The metal envelope also permits maintaining the cohesion of the refractory mat¬erial when cracks appear under the effect of thermal and mechanically elevated atresaes induced by the casting conditions'.
Exposition of the techinogical Problem
Because the upper plate is longer, it is also more costly to produce.
On the other hand, the fact that the dimensions of the plates are different necessitates the management of different components,

particularly when -she refractory plates are surrounded by a metal envelope, the production of Which requires a costly investment in tooling equipment. The purpose of the present invention is a plate changing drawer that resolves these disadvantages.
According to the invention, the upper plate and the lower plate have identical polygonal peripheries and are angularly offset so that they ovarlap completely.
Thus, the surface of the fixed plate directed toward the replace¬ment plate that in not covered by the plate during pouring can serve as a guide surfaco for the replacement plate. Thus, although the
,
surfaces of the plates are equal we have a guide surface that permits a perfect alignment of the upper fact of the lower platt with the lower surface of the. upper plate.
furthermore, the same metal envelope can be used for the two types of plate, also in. the case where their internal constitution is dif¬ferent. The coat of the tooling equipment necessary for producing the metal envelopes is out in two.
Preferably, the polygonal periphery of the plates is a square and the taphole is placed in the center of the square.

Also .preferably, the fixed plate and the replaceable plate are offset angularly by 4-5".
Preferably, the two surfaces lateral to the direction of intro¬duction of the plates of the fixed plate which are never covered by the lower plate, either when the plates are in the casting position or during the changing of plates, are used to fix it on the drawer chassis, for example, by means of screws with a conical end, each acting on one edge of the fixed plate situated in the lateral zone

not covered by the lower plate, these edges being situated at the front of this fixed plate with respect to the direction of introduc¬tion of the replacement plates in order to move the fixed plate simultaneously toward the back and against the drawer chassis.
One is then sure that during the successive plate changes the fixed plate would not be displaced to recover a possible assembling play, which would then run the risk of damaging the Joint of the fixed plate with the casting spout inside of the distributor.

Therefore, the present invention relates to a plate change drawer for a metallurgical vessel such as a continuous casting distributor, the drawer comprising a chassis mounted under the metallurgical vessel, at least one fixed upper plate and at least one replaceable lower plate, means (24) for applying pressure to force the lower plate against "he fixed plate, the chassis having guide means (34) for receiving a lower replacement plate alongside the lower plate during pouring, and actuation means (38) for bringing the lower replacement plate in the place of the plate during pouring, characterized in that the upper fixed plate and the lower replaceable plate have identical polygonal peripheries and are offset angularly so that they do not overlap completely.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Other characteristics and advantages of the present invention will become evident in reading the following description with refer¬once to the attached Figures.
Figure 1 is a longitudinal cross sectional view of a plate changing drawer in accordance with the invention.
Figure 2 is a bottom view of the plate changing drawer shown in figure 1.
On Figure 1 a distributor 2 has a bottom wall of steel 4 covered with a protective layer of refractory material 6. A pouring orifice. or taphole 8 is effected in the bottom of the distributor 2- A plate changing drawee designated as a whole by the general reference 10 is mounted under the distributor 2. A ring 14 is welded inside of the distributor ON the bottom wall. Screws 16 fasten the chassis 12 of the drawer on this ring 14. A fixed refractory plate 13 is placed in a seat 2O of the chassis 12. A lower plate 22 is located under the fixed plate 13. The plate 22 is applied against the fixed plate 18 by means of pressure application constituted in the example shown by four rocker arms 24. As can be seen on Figure 2, each rocker arm has around and applied, on the lower face of the lower plate 22, and one

and 24b pressed dowaward by a helicoidal spring 26. Essentially at its central part the rocker arm 24 is articulated on & bolt with a spherical bead 28. The action exerted on the lower plate by these means of pressure application make a it possible to effect a, tight junction of tat fixed plate -18 and the lower plate 22.
As can be seen on figure 2, the fixed plate 18 and the lower Plata 22 have identical peripheries, i.e., of the same shape and the
same surface.
The fact that the plates 18 and 22 have identical peripheries is advantageous because this permits use of the same metal envelopes

for these two plates. In this menner a single tooling outfit is sufficient. The inveatment required is thus cut in two.
The- platea are preferably square. For practical reasons, notably of manufacture, the angles of the squares are rounded. The fixed plate 18 and the lower plate 22 have a tapbola 21. This taphole is placed in the center of the square periphery.
It is also noted that the fixed plate 18 and the lower plate 22 are angularly off let. In this manner, their surfaces are not covered completely. More particularly, the aurfaoa of the fixed plate 18 is not covered completely by the lower plate 22.
At the front of the fixed plate 16 with respect to the direction of Introduction and exchange of the platea there is a triangular zone (the vertex of which is rounded) 18a. Apart from a plate exchange, this zone is not covered by thelower plate 22. It can thus be used is a guide surface for the replacement plate. Thus, although the aurfaoes of the platea are equal, there is a guide surface that per¬mitd a perfect alignment of the upper face of the lower plate with the lower face of the upper plate.

On either side or the plate 18, laterally with respeot to the direction of plate change, there are two zone a 18b, triangular in shape with a rounded end. These two zones are never oovered by the lover plate 22, even during a plate exchange. These zones 18b can thus be used to maintain the fixed plate 18 toward the bottom of the seat 20 and toward the back of the frame 22. For this, the fixed plate 18 is held in its seat 20 by two screws 30 that have a conical head 3Oa. The conical end 3Oa of each of the two screws 30 acts on an edge of the fixed plate 18 located in zone 18b, at the front of this zone with respect to the direction of introduction of the plates. The oonioal ends exert an action that applies the plate 18 toward the bottom of the seat 20, i.e., upward, and simultaneously an action that applies the fixed plate 18 toward the back of the frame 12 with respect to the direction of introduction of the plates.
It is advantageous to apply the fixed plate 18 toward the back of the frame to avoid a backlash between the plate 18 and the back corner of the sent 20 when the plates are exchanged. In effect, this backlash, even minimal, would have the effect of impairing the quality of the joint between the fixed plate 18 and the mass to be rammed 32 located in the thickness of the refractory lining 6 of the distributor 2. The screws 30 make it possible to eliminate this play.
According to an actualization variant, the periphery of the fixed plate 18 has elastic means placed on two sides adjacent to an angle of the square piriphery. These elastic means, comprised for example of elastic fibers or cardboard, are located at the time of assembly of the plate 18 in its seat 20 toward the front of the frame so as to automatically position the two opposite sides of the square against

rigid supporte effected in the chassis 12 for receiving them.
The chassis 12 has guide means that permit receiving a lower replacement plate 22 alongside the lower plate 22 during casting. In the exemplary embodiment shown the guide means are comprised of a slide rail 34(see figure 2) located toward the front of the mach¬ine with respect to the direction of introduction of the replacement plate 22a. The plate 22a is mounted on a support 36. Actuation means comprised, for example, of a hydraulic or pneumatic jack 33 are connected to the support 36•
First, the lower replacement plate 22a is introduced into the slide rails 34 until the orosspieoe 40 that is part of the means of support is retained behind two arms 42 articulated on the chassis 12. The two arms 42 are connected by an elastic means 44. When the sup¬port 36 carrying the replacement plate 22a is introduced, the articu¬lated arms pivot around their axis sc that their ends are separated. When the support 36 is introduced sufficiently into the guide means 34, the ends of the articulated arms 42 will look on the crosspieoe 40. At this time the replacement plate 22a is essentially in contact with the lower plate 22 in the pouring position.The actuation means 38 are then set in motion to expel the plate during pouring to re¬place it with the new plate 22a. The position shown in Figure 1 is then occupied. The worn lower plate falls by itself out of the guide means.
The operator then acts on a lever arm 46 that deflects the two articulated arms 42 to free the aupport 36 and the orosspieoe 40 and equip it with a new replacement plate.


WE CLAIM:
1. Plate change drawer for a metallurgical vessel such as a continuous
casting distributor [2], the drawer comprising a chassis (12) mounted
under the metallurgical vessel, at least one fixed upper plate [18] and
at least one replaceable lower plate (22), means (24) for applying
pressure to force the lower plate (22) against the fixed plate, the
chassis (12) having guide means (34) for receiving a lower replacement
plate (22) alongside the lower plate (22) during pouring, and actuation
means (38) for bringing the lower replacement plate (22) in the place
of the plate during pouring, characterized in that the upper fixed plate
(18) and the lower replaceable plate (22) have identical polygonal
peripheries and are offset angularly so that they do not overlap
completely.
2. A drawer as claimed in claim 1, wherein the polygonal peripheries of
the plates is a square or a square with the rounded corners.
3. The drawer as claimed in claim 1 wherein the tap hole is placed in the
center of the square for each plate.
4. A drawer as claimed in claim 1 wherein the fixed plate and the
replaceable plate are offset angularly by 45°.
5. A drawer as claimed in claim 1 wherein the two surfaces [18b] lateral
to the direction of introduction of the plates of the fixed plate that are
never covered by the lower plate [22] are used to fastened it on the
chasses [12] of the drawer.
6. The drawer as claimed in claim 1 having two screws (30) with a
conical end (30a), each of which acts on a edge of the fixed plate
located in the lateral zone [18b] not covered by the lower plate (22),
these edges being located in front of this fixed plate with respect to

the direction of introduction of the replacement plates in order to push the fixed towards the back and against the chassis (12) of the drawer.
7. A set of plates for a drawer as claimed in claim 1, comprising a. fixed
plate and a replaceable plate characterized in that these plates have
identical polygonal peripheries and a tap hole situated in the center of
the square peripheries and to be offset angularly from each other.
8. A set of plates as claimed in claim 7, wherein the periphery of the
fixed plate has elastic means (44) placed on two sides adjacent to a
corner of the square periphery for automatic positioning of two
opposite sides of the square against rigid support effected in the
chassis [12] for receiving them during the mounting of the fixed plate.
9. A set of plates as claimed in claim 7, wherein they are provided with
identical metal envelopes.
10. Plate change drawer for a metallurgical vessel substantially as
hereinbefore described with reference to and as illustrated in the
accompanying drawings.
11. Set of plates for a drawer substantially as hereinbefore described with
reference to and as illustrated in the accompanying drawings.



Documents:

2770-del-1996-abstract.pdf

2770-del-1996-claims.pdf

2770-del-1996-correspondence-others.pdf

2770-del-1996-correspondence-po.pdf

2770-del-1996-description (complete).pdf

2770-del-1996-drawings.pdf

2770-del-1996-form-1.pdf

2770-del-1996-form-13.pdf

2770-del-1996-form-19.pdf

2770-del-1996-form-2.pdf

2770-del-1996-form-4.pdf

2770-del-1996-form-6.pdf

2770-del-1996-gpa.pdf

2770-del-1996-petition-138.pdf

abstract.jpg


Patent Number 214914
Indian Patent Application Number 2770/DEL/1996
PG Journal Number 10/2008
Publication Date 07-Mar-2008
Grant Date 18-Feb-2008
Date of Filing 11-Dec-1996
Name of Patentee VESUVIUS FRANCE S.A.
Applicant Address 68, RUE PAUL DEUDON, BP 19, 59750 FEIGNIES, FRANCE.
Inventors:
# Inventor's Name Inventor's Address
1 FRANCOIS-NOEL RICHARD 78 AVENUE ANATOLE FRANCE, 54000 NANCY, FRANCE.
PCT International Classification Number B65d 75/38
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 95 15885 1995-12-26 France