Patent Publication Number: US-9884366-B2

Title: Closure plate, and a slide closure on the spout of a container containing molten metal

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 13/976,506 filed Jun. 27, 2013, now U.S. Pat. No. 9,266,169, which is a National Stage application of PCT/EP2012/000306 filed Jan. 24, 2012. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to a closure plate for a slide closure on the spout of a container containing molten metal in which two outer longitudinal sides, a flow-through opening disposed on a central longitudinal axis of the closure plate and a closing surface passing from the latter are provided; and a slide closure for the latter. 
     BACKGROUND OF THE INVENTION 
     Generic closure plates in a slide closure are used for opening and closing the passage of molten metal. The closure plates respectively provided with a flow-through opening are therefore pressed against one another such as to form a seal, and by means of a drive the one closure plate can be moved over a defined distance from the open into a closed position and vice versa. Thus, both on the upper fixed and on the moveable closure plate closing surfaces are formed, the length of which corresponds to the adjustment distance. The closure plates are either clamped into the mechanism of the slide closure, as provided in a slide closure according to publication DE-A-35 22 134, or else are inserted in the mechanism with practically no play, as displayed by the plates disclosed in publication EP-A-1 064 155. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     The object underlying the present invention is to provide a closure plate of the type mentioned at the start which, in particular with clamping on the outside, is provided with minimum dimensions and optimal clamping so that the closure plate offers a high level of reliability during operation when the closure is closed, and the outer plate dimensions are thereby, however, kept to a minimum in relation to the diameter of the flow-through opening. 
     According to the invention, the object is achieved by a closure plate for a slide closure on the spout of a container containing molten metal in which two outer longitudinal sides, a flow-through opening arranged on a central longitudinal axis of the closure plate and a closing surface passing from the closure plate are provided. On each of these two outer longitudinal sides, at least two shoulder surfaces are formed, serving as clamping surfaces or as centering surfaces of the closure plate which are at an angle to the longitudinal axis forming tapering of the plate. At least on the shoulder surfaces on the side of the closing surface, adjoining outer sides are provided which are respectively at a smaller angle to the longitudinal axis than those of the shoulder surfaces, or are arranged approximately parallel to the longitudinal axis. 
     In its embodiment according to the invention, this closure plate can have minimal dimensions because by means of these at least two shoulder surfaces in the form of clamping surfaces on each of the two outer longitudinal sides, optimal clamping of the closure plate can be achieved. Since these shoulder surfaces form tapering of the plate, the closure plate can have minimal dimensions. That these outer sides adjoining the side of the closing surface at the clamping surfaces and forming the plate end respectively have a smaller angle than that of the shoulder surfaces, sufficient reliability is guaranteed, even with repeated use of the closure plates. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Exemplary embodiments and further advantages of the invention are described in more detail using the drawings. These show as follows: 
         FIG. 1  is a longitudinal section of a diagrammatically illustrated slide closure and the closure plates fastened in the latter, 
         FIG. 2  is a top view of a closure plate according to the invention, 
         FIG. 3  is a top view of a variant of a closure plate, 
         FIG. 4  is a top view of a further variant of a closure plate, and 
         FIG. 5  is a top view of a fourth variant of a closure plate. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows a section of a slide closure  10  mounted on a container, only the outer steel jacket  11  with a centring ring  14 , a fire-proof inlet sleeve  13  forming the container outlet and a fire-proof lining  12  of the container being indicated. A pan of a continuous casting plant that can be filled with molten steel is normally provided as the container. Needless to say, however, this can be a container holding any molten metal. 
     Adjoining this inlet sleeve  13 , forming a seal, is an upper fire-proof closure plate  20  fastened in the housing  18  of the slide closure  10  and which is in sliding contact with a moveable fire-proof closure plate  22  in a slider unit (not detailed), the slider unit being moveable to and fro by a drive, and moreover being fastenable on the housing  18  by clamping components (not shown). Furthermore, there is adjoining the moveable closure plate  22  another fire-proof spout sleeve  16 . 
       FIG. 2  shows the closure plate  20  which consists of a sheet metal jacket  23  and a fire-proof plate  20 ′ mortared in the latter. It has two outer longitudinal sides, a flow-through opening  21  disposed on a central longitudinal axis A and a closing surface S passing from the latter. This closing surface S is defined by the diameter of the flow-through opening of the opposite closure plate and by the adjustment distance of the slider unit. In  FIG. 1 , the slide closure  10  is in the closed position in which the end of the closing surface of the lower moveable closure plate  22  covers, i.e., aligns with, the flow-through opening  21  of the upper closure plate  20 . 
     According to the invention there are formed on each of these two outer longitudinal sides of the closure plate  20  two shoulder surfaces  20   a ,  20   b  serving as clamping surfaces or as centring surfaces which are at an angle α, β to the longitudinal axis A and thereby form tapering of the plate. By virtue of the metal jacket  23  being around the fire-proof plate  20 ′, some of the shoulder surfaces  20   a ,  20   b  are defined on the metal jacket  23 . Moreover, the outer sides  20   c , which adjoin the shoulder surfaces  20   a  located on the side of the closing surface S, are respectively at a smaller angle γ to the longitudinal axis than those of the shoulder surfaces  20   a.    
     In the present exemplary embodiment, these angles α, β on the longitudinal sides of the closure plate  20  have the same dimensions, namely approx. 20°. However, the angle γ of the respective outer side  20   c  is preferably between 0 and 20°, in this case approx. 5°. In relation to the longitudinal axis A the closure plate  20  is, furthermore, symmetrical in form, whereby there are the same angles and the same dimensions on both longitudinal sides. 
     These shoulder surfaces  20   a ,  20   b  of the closure plate  20  provided at an angle α,  13  to the longitudinal axis A are positioned a distance  27   a ,  27   b  away from the transverse axis of the flow-through opening  21 . The clamping elements  17   a ,  17   b  acting on the shoulder surfaces  20   a ,  20   b  in the operating state, and which form part of the slide closure  10 , and so are indicated by dots and dashes, generate a resulting clamping force line  25   a ,  25   b  extending perpendicular to the respective shoulder surface  20   a ,  20   b  towards the centre of the plate and which intersects the longitudinal axis A at the intersection point  26   a ,  26   b.    
     Advantageously, within the framework of the invention the intersection point  26   a ,  26   b  formed by this respective clamping force line  25   a ,  25   b  and longitudinal axis A lies a specific distance  27   a ,  27   b  away from the outer diameter of the flow-through opening  21 , i.e., a distance from a line transverse to the longitudinal axis A and passing through the center of the flow-through opening  21  as shown in  FIG. 2 . This distance generally corresponds to maximum twice the diameter of the flow-through opening  21  and is larger on the side of the closing surface S than on the opposite side. In  FIG. 2  this distance is illustrated as smaller than this diameter of the flow-through opening. 
     This distance  27   a ,  27   b  between the shoulder surfaces  20   a ,  20   b  and the transverse axis of the flow-through opening  21  gives a considerable advantage in that the clamping forces acting in the region around the flow-through opening and the cracks occurring in the fire-proof material around the flow-through opening due to the thermal load do not lead to breakage of the fire-proof material. This crack formation in the fire-proof plate  20 ′ can, however, be specifically influenced by this clamping according to the invention so that the durability of the plate is critically improved. 
     Furthermore, the ends of the closure plate  20  are respectively formed in the conventional manner by two radii which respectively pass from the outer side  20   c  or from the shoulder surface  20   b . Moreover, the outer longitudinal sides in the region  28  between the shoulder surfaces are arranged parallel to the longitudinal axis. In principle the latter could also be oval or similar in shape. 
       FIG. 3  shows a closure plate  30  consisting of a plate and a sheet metal jacket which is similar in form to that of  FIG. 2 , and so in the following only the differences will be described. Two shoulder surfaces  30   a ,  30   b  are in turn respectively assigned to both outer longitudinal sides, symmetrically to the longitudinal axis A. Adjoining the two shoulder surfaces  30   b  on the side facing away from the closing surface S, outer sides  30   d  are provided which are respectively at a smaller angle to the longitudinal axis A than those of the shoulder surfaces  30   b . These outer sides  30   d  extend, like the opposite outer sides  30   c  adjoining the shoulder surfaces  30   a , approximately parallel to the longitudinal axis A. These outer sides  30   c ,  30   d  to both sides of the shoulder surfaces form a level plate width. The two ends on the closure plate are respectively semi-circular in shape. 
     The closure plate  40  according to  FIG. 4  is in turn similar in form to that according to  FIG. 2 , and the differences are displayed below. The shoulder surfaces  40   a  are not formed as straight surfaces, but as round surfaces. The radius  40   r  (from a center of the flow-through opening  21 ) is chosen here such that it practically forms the radius of the plate end  40   e  (from the center of the flow-through opening  21 ). The closure plate  40  could thus be inserted into a circular recess in the mechanism of the slide closure without clamping taking place. Also, as in the embodiment of  FIG. 2 , the shoulder surfaces  40   b  extend from a part parallel to the longitudinal axis to the plate end  40   e.    
       FIG. 5  shows a closure plate  50  in which, as a special feature, the shoulder surfaces  50   a ,  50   b  are arranged on the outer longitudinal sides at right angles to the longitudinal axis A so that these angles α, β are 90°. These shoulder surfaces  50   a ,  50   b  are preferably dimensioned with a short length of just a few millimeters, whereas in the above variants the shoulder surfaces respectively have a length of preferably 30 to 100 mm. This closure plate  50  is especially suitable for being inserted, with practically no play and without clamping, into the mechanism of the slide closure. In the mechanism corresponding recesses would have to be provided in which these centring shoulders  51  with the shoulder surfaces  50   a ,  50   b  formed on the latter would be accommodated with practically no play. The centring shoulders  51  with their shoulder surfaces  50   a ,  50   b  are formed by the sheet metal jacket  52  surrounding the fire-proof plate  50 ′. 
     These shoulder surfaces  50   a ,  50   b , preferably dimensioned with a short length of just a few millimeters, could, however, also be formed at less than 90° to the longitudinal axis A. 
     The invention is sufficiently demonstrated by the above exemplary embodiments. Further variants could also be provided, however. Thus, for example, instead of a sheet metal jacket, just a sheet metal collar surrounding the plate could be inserted, or the plate could also be inserted directly into the mechanism of the slide closure and, if appropriate, be clamped within the latter. 
     Theoretically, at least one of the shoulder surfaces on the one longitudinal side could be of a different length to the corresponding one on the other longitudinal side or could be provided at a different angle. This could offer the advantage that when the closure plates are turned after the container has been emptied a specific number of times, and so the rear side becomes the sliding side, the latter can first of all be used as the slider plate, and after turning only as the base plate. 
     In view of the foregoing, a slide closure  10  in accordance with the invention includes a closure plate  20  defining a flow-through opening  21  on a longitudinal axis A through which molten metal operatively flows and having a closing surface S on one side of the flow-through opening  21 . The closure plate  20  includes a first outer longitudinal side  20   c  on one side of the flow-through opening  21  and a second outer longitudinal side  20   c  on an opposite side of the flow-through opening  21  from the first longitudinal side. The closure plate  20  also includes a first shoulder surface  20   a  on the first longitudinal side, a second shoulder surface  20   b  on the first longitudinal side spaced apart from the first shoulder surface  20   a , the first and second shoulder surfaces each being entirely distanced from a transverse axis passing through a center of the flow-through opening  21 , a third shoulder surface  20   a  on the second longitudinal side, and a fourth shoulder surface  20   b  on the second longitudinal side spaced apart from the third shoulder surface  20   a , the third and fourth shoulder surfaces each being entirely distanced from the transverse axis passing through the center of the flow-through opening  21 . The first, second, third and fourth shoulder surfaces  20   a ,  20   b  are each preferably at a respective angle to the longitudinal axis which is greater than 0° and inwardly oriented such that each shoulder surface  20   a ,  20   b  has an inward taper toward the longitudinal axis. A housing  18  accommodate the closure plate  20 , and clamping elements  17   a ,  17   b  clamp the closure plate  20  in the housing  18  by pressing the first, second, third and fourth shoulder surfaces  20   a ,  20   b , see  FIG. 2 . The clamping elements  17   a ,  17   b  generate inward oriented clamping force lines  25   a ,  25   b  which intersect the longitudinal axis A, see  FIG. 2 .