Abstract:
The invention relates to a continuous casting device comprising a support structure ( 16, 116 ), a swing lever ( 24, 124 ) which is pivotally mounted in the support structure ( 16, 166 ) around a first pivotal axis a drive mechanism ( 34, 134 ) which is connected to said swing lever ( 24, 124 ) and a continuous casting shell ( 14, 114 ) which can be impinged upon a cooling medium. A bearing ( 38, 138 ) to support the continuous cast shell ( 14, 114 ) is pivotally mounted on the swing lever ( 24, 124 ) around a second pivotal axis, whereby at least one connection for the cooling medium is integrated into the pivoting bearing ( 38, 138 ).

Description:
This application is a continuation of PCT/EP98/03134 having an International filing date of May 28, 1998 and which is incorporated herein by reference in its entirety. 
    
    
     FIELD OF THE INVENTION 
     The invention relates to continuous casting equipment, in particular continuous casting equipment with an integrated vibrating device. 
     BACKGROUND OF THE INVENTION 
     It is known how to vibrate the mould in the casting direction to prevent adherence of the billet to the cooled inner walls of the casting pipe in the continuous casting of metals, in particular in the continuous casting of steel. 
     A conventional vibrating device of continuous casting equipment comprises a lifting table, on which the continuous casting mould is arranged as a unit. These lifting tables are relatively heavy and in addition require quite a large amount of space under the mould, where this space is not always available. 
     The international patent application WO 95/03904 describes a mould which has a fixed casing, to which a casting pipe is connected via two flexibly deformable annular sealing diaphragms in such a way that it can vibrate in the casing along the casting axis. The annular sealing diaphragms seal an annular pressure chamber for a cooling liquid around the casting pipe. The casting pipe comprises at its top end lateral bearing journals, with which it is suspended in an oscillating lever. The latter is pivoted about a horizontal axis in the casing. A lever arm is led through a seal from the pressure chamber and connected to a lifting cylinder, which generates the vibrations. With this mould the weight of the parts to be vibrated and thus the power input are greatly reduced. A disadvantage of this mould is that changing of the casting pipe is relatively time-consuming, because the annular sealing diaphragms must first be dismantled. 
     International patent application WO 95/05910 describes a compact vibrating device, which has an annular lifting cylinder, into which a mould consisting of a casting pipe and a cooling box can be suspended axially. The cooling box of the mould is connected via flexible pipe connections to fixed connection pieces for the purpose of connection to a cooling water circuit. 
     SUMMARY OF THE INVENTION 
     The present application is based on the task of producing continuous casting equipment with an integrated compact vibrating device, whereby it should be possible to connect the continuous casting mould to be vibrated particularly easily to a cooling circuit when changing it. This problem is solved by continuous casting equipment according to the present invention. 
     Continuous casting equipment according to the invention comprises a supporting structure, an oscillating lever, which is pivoted about a first swivelling axis in this supporting structure, a drive connected to the oscillating lever and a continuous casting mould, which can be supplied with a cooling medium. A bearing for supporting the mould is pivoted about a second axis in the oscillating lever. At least one connection for a cooling medium is integrated in the bearing. The mould is supported by the bearing and is detachably connected to the at least one connection for the cooling medium, so that it can easily be installed and dismantled as a unit, whereby the pivoted bearing remains mounted on the oscillating lever during dismantling of the mould and the cooling medium connection integrated in the bearing can consequently remain connected to an external cooling circuit. Consequently no flexible pipe connection need be broken and re-established between an external cooling circuit and the pivoted mould when changing the mould. It should also be noted that the oscillating lever with a vibrating bearing with an integrated connection for the cooling medium is an extremely compact vibrating device. 
     In a preferred embodiment of the continuous casting equipment, first connection means are integrated in the swivelling bearing and second connection means in the mould, these first and second connection means being complementary to each other in such a way that they interact when the mould is placed on the swivelling bearing to form a sealed transition for the cooling medium. The mould can accordingly be connected to an external cooling circuit without separately assembled pipes by simply mounting the mould on the swivelling bearing. 
     The bearing can be formed by a collector ring, which is pivoted in the oscillating lever. The mould is placed in this collector ring and sealed by top and bottom sealing means in relation to the collector ring, so that the collector ring and sealing means form an annular collector around the mould. In an advantageous embodiment these sealing means comprise a top and bottom sealing flange on the mould, the top sealing flange resting by means of a first seal on a top sealing face of the collector ring and the bottom sealing flange by means of a second seal on a bottom sealing face of the collector ring, the top sealing flange being larger than the bottom sealing flange. Consequently the mould can easily be placed from above in the collector ring. The mould advantageously has an annular sealing rib between the upper and lower sealing flanges, which rests with a seal on an inner surface of the collector ring in order to separate a feed chamber and a return chamber in the connection collector. 
     In an alternative embodiment the bearing comprises a first connection plate, in which at least one cooling medium connection forms a first opening, which is enclosed by a first sealing face. A second connection plate with at least one second opening for introduction or removal of a cooling medium is arranged on the mould. When the mould rests on the bearing in the operating position, the two openings are in alignment with each other, and a second sealing face, which encloses the second opening and is complementary to the first opening, is pressed against the first sealing face to form a seal. At least one of the two sealing faces opposite each other is advantageously formed by a ring which can be displaced axially against a spring element. In this embodiment satisfactory sealing is also ensured if more than one opening has to be sealed. For example, the first connection plate on the bearing and the second connection plate on the mould can each have at least one opening for a cooling medium feed and cooling medium return flow. 
     A mould for the continuous casting equipment described above advantageously has a projection, in which the second connection plate is integrated. A suitable bearing can then have two parallel supporting arms for the mould, the first connection plate connecting the two supporting arms in such a way that a forked bearing is formed for the mould. 
     The first and second sealing faces resting on each other are preferably essentially horizontal, so that the weight of the mould and the tensile force on the billet contribute to the generation of a contact force between the sealing faces. 
     The continuous casting mould advantageously rests with its top end on the swivelling bearing, guide means being arranged on the bottom end of the continuous casting mould to guide it in the supporting structure. These guide means may, for example, comprise a guide ring or a guide rod. 
     To achieve a particularly compact construction the second swivelling axis can be formed by swivel joints arranged between the first swivelling axis and the point of application of the drive on the oscillating lever. However, these swivel joints can also be arranged at one end of the oscillating lever. 
     Cooling medium connections integrated in the swivelling bearing can be connected by compensators to fixed connections of an external cooling circuit. A particularly long life of these compensators is achieved if they are installed in such a way that their central axis is essentially parallel with the stroke direction, which can be accomplished particularly easily in equipment according to the invention. 
     However, cooling medium connections integrated in the swivelling bearing can also be connected via ducts in the oscillating lever to an external cooling circuit. These ducts can each be connected to a fixed connection piece on the supporting structure via a first swivel joint connection arranged coaxially with the first swivelling axis and to the connections in the bearing via a second swivel joint connection arranged coaxially with the second swivelling axis. 
     If an electromagnetic agitator is provided, this is preferably supported directly by the supporting structure. The drive of the oscillating lever advantageously comprises a hydraulic cylinder, which rests with one end on the supporting structure and with its other end on the oscillating lever. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Exemplified embodiments of the invention are explained with the aid of the enclosed schematic drawings. 
     FIG. 1 shows a longitudinal section through a first embodiment of continuous casting equipment according to the invention; 
     FIG. 2 a longitudinal section through the equipment in FIG. 1, the most important components of the equipment being shown separately; 
     FIG. 3 a plan view of the continuous casting equipment in FIG. 1; 
     FIG. 4 a longitudinal section through a second embodiment of continuous casting equipment according to the invention; 
     FIG. 5 a longitudinal section through the equipment in FIG. 4, the most important components of the equipment being drawn separately; 
     FIG. 6 a side view of the continuous casting equipment according to FIG. 4, the connection box of the mould being drawn as a section; 
     FIG. 7 a plan view of the vibrating device of the continuous casting equipment according to FIG. 4; 
     FIG. 8 an enlarged section from FIG.  4 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     All the figures relate to continuous casting equipment according to the invention, as can be used, for example, for continuous casting of steel billets. 
     A first embodiment of such equipment is shown schematically in FIGS. 1 to  3  and designated  10 . It consists essentially of a compact vibrating device  12 , in which a continuous casting mould  14  (shaded portion in the drawing) is suspended. This continuous casting equipment is shown ready for operation in FIGS. 1 and 3, i.e. the continuous casting mould  14  is inserted or suspended in the vibrating device  12 . By contrast, the main components of the equipment  10  are shown individually before assembly in FIG.  2 . 
     The vibrating device comprises a supporting structure  16  with a base  18  and a superstructure  19 , the latter forming two symmetrically arranged supporting arms  20 ,  22  at its top end (see in particular FIG.  3 ). A two-armed rocking lever  24  is pivoted about a horizontal axis  25  in the supporting arms  20 ,  22 . The two lever arms  26 ,  28 , each of which is connected mechanically at one end via a pivot bearing  30 ,  32  to one of the two supporting arms  20 ,  22 , are shown in FIG.  3 . At the opposite end the oscillating lever  24  is connected to a drive  34 , which produces a swivelling movement of the oscillating lever  24  about the swivelling axis  25 . The drive  34  is advantageously designed as a hydraulic cylinder, which is mounted between the base  18  and a transverse connection  36  of the two lever arms  26 ,  28 . 
     In the two-armed rocking lever  24  a bearing  38  for the mould  14  is pivoted about a horizontal axis  39  (see FIG.  3 ). This swivelling axis  39 , which is essentially parallel with the swivelling axis  25 , is formed by two pivot bearings  40 ,  42 , which are arranged in the two lever arms  26 ,  28 . As shown in FIG. 2, the swivelling bearing  38  comprises a collector ring  41 , into which the mould  14  is inserted with a seal. A connection box on the collector ring  41 , which has a connection piece  44  for a cooling medium feed pipe  46  and a connection piece  48  (see FIG. 3) for a cooling medium return pipe  50 , is designated  43 . Axial compensators  52  connect the connection pieces  44  or  48 , which can be swivelled with the bearing  38 , to the fixed cooling medium feed pipe  46  or the cooling medium return pipe  50 . It can be seen that the central axis of the compensators  52  is essentially parallel with the swivelling movement of the mould  14 , so that they have to absorb essentially axial movements. A guide ring on the supporting structure  16 , into which the bottom end of the mould  14  is inserted (see FIG.  1 ), is designated  54 . This guide ring  54  determines the alignment of the mould  14  supported by the swivelling bearing  38  during vibration and likewise absorbs the horizontal forces which act on the continuous casting mould  14  during continuous casting. An electromagnetic agitator  56 , which is supported by the supporting structure  16  and encloses the mould, is designated  56  in FIGS. 1 and 2. 
     The construction of the mould  14  is described in more detail with the aid of FIG. 2, in which it is shown dismantled. It consists essentially of a casting pipe  58 , which forms the actual casting duct  60 , and a cooling box  62 , which encloses the casting pipe  58  over its full length when the mould  14  is assembled. The cooling box  62  comprises essentially an outer shell  64  and an inner guide shell  66 , which is arranged between the outer shell  64  and the casting pipe  58  in the assembled mould  14 . At its bottom end the outer shell  64  has a base plate  68  with an opening  70  for sealed fitting of the bottom end of the casting pipe  58  (see also FIG.  1 ). At its top end the outer shell  64  has a sealing flange  72 , which can be mounted with a seal on a bottom sealing ring  74  of the collector ring  41  (see FIG.  1 ). The guide shell  66  is secured by means of straps on the outer shell  64 . Above the sealing flange  72  the guide shell  66  has an annular sealing rib  78 , which can be fitted with a seal into an opening  80  in an intermediate plate  82  of the annular collector  40  (see FIG.  1 ). A sealing flange  84  is secured at the top end of the casting pipe  58 . This flange can be placed on a top sealing face  86  of the connection box  43  (see FIG.  1 ). 
     The cooling circuit of the mould  14  will now be described in more detail with the aid of FIG.  1 . The cooling medium, usually cooling water, flows from the feed pipe  46  via the feed connection piece  44  into a bottom feed chamber  88  in the connection box  43  of the annular collector  40 . This feed chamber  88  encloses a lateral annular gap  90 , which is formed between the bottom sealing flange  74  and the sealing rib  78  of the mould  14 . The cooling medium flows via this annular gap  90  from the feed chamber  88  of the bearing  38  into the mould  14 , where it is guided through an annular duct  92  between the outer shell  64  and the guide shell  66  to the bottom end of the mould  14 , where it flows via a gap between the guide shell  66  and the base plate  68  into an annular duct  94  between the guide shell  66  and the casting pipe  58 . The cooling medium flows back through the annular duct  94  to the top end of the mould  14  and cools the casting pipe  58 . At the top end of the mould the cooling medium flows through a lateral annular gap  96  between the sealing rib  78  and the top sealing flange  84  of the mould  14  and then from the latter into a return chamber  98 , which encloses the annular gap  96  and extends into the connection box  43 . The cooling medium finally flows back into the return pipe  50  via the return connection piece  50 , which discharges into the top return chamber  98 . 
     An alternative embodiment of the invention is described with the aid of FIGS. 4 to  8 . The continuous casting equipment  110  likewise consists of a compact vibrating device  112  and a continuous casting mould  114  (see FIG. 5, in which the main components of the vibrating device are shown separately), which is inserted into the vibrating device  112  (see FIG. 4, in which the vibrating device is shown in the operating condition). The vibrating device  112  comprises a supporting structure  116  with a base  118 . A pair of supporting arms  120 ,  122  arranged symmetrically with the mould  114  extends upwards from the base  118  (see in particular FIGS.  6  and  7 ). A two-armed rocking lever  124  is pivoted in the supporting arms  120 ,  122  about a horizontal axis  125 . The two lever arms  126 ,  128 , which are each connected mechanically in the centre via a pivot bearing  130 ,  132  to one of the two supporting arms  120 ,  122 , can be seen in FIG.  7 . At one end, the oscillating lever  124  is connected to a drive  134 , which produces a swivelling movement of the oscillating lever  124  about the swivelling axis  125 . The drive  134  is advantageously designed as a hydraulic cylinder, which is mounted between the base  118  and a transverse connection  136  of the two lever arms  126 ,  128 . 
     A bearing  138  for the mould  114  is pivoted about a horizontal axis  139  at the other end of the two-armed rocking lever  124  (see FIG.  7 ). The bearing comprises a connection plate  141  and two lateral supporting arms  143 ,  145 , a forked bearing for the mould  114  being formed, as shown in FIG.  7 . The swivelling axis  139 , which is essentially parallel with the swivelling axis  125 , is formed by two pivot bearings  140 ,  142 , each of which connects one of the two supporting arms  143 ,  145  to one of the two lever arms  126 ,  128 . Two openings  145 ,  147  for a cooling medium are arranged in the connection plate  141  (see FIG.  7 ). The first opening  145  terminates via a sealing device  149  described further below in a connection piece  144  for a cooling medium feed pipe  146 . The second opening  147  terminates via a similar sealing device  149  in a connection piece  148  (see FIG. 6) for a cooling medium return pipe  150 . A guide ring  154  on the supporting structure  116  corresponds to the guide ring  54  described above. The reference number  156  indicates an electromagnetic agitator. 
     Like mould  14 , mould  114  also consists essentially of a casting pipe  158  and a cooling box  162 . The cooling box  162  with its outer shell  164  and guide shell  166  differs from the cooling box  62  described above essentially by a connection box  167  at its top end. The remainder of the cooling box  162  is otherwise identical with the cooling box  62 . The casting pipe  158  inserted in the cooling box  162  is likewise identical with the casting pipe  58  of the equipment  10 . A sealing flange  184  mounted at the top end of the casting pipe  158  is placed with a seal on a top sealing face  186  on the connection box  167  of the cooling box  162  (see FIG.  4 ). 
     The connection box  167  has a lateral projection  187 , which is closed at the bottom by a connection plate  189  with two openings  191 ,  193  for a cooling medium. When the mould  114  rests on the bearing  138  in the operating position (see FIG.  4 ), these openings  191 ,  193  in the connection plate  189  are aligned above the openings  145 ,  147  in the connection plate  141  of the bearing  138 , complementary sealing faces, which enclose the individual openings  145 ,  147 ,  191 ,  193 , being pressed against each other with a seal. 
     The sealing faces which enclose the openings  145 ,  147  in the connection plate  141  of the bearing  138  are advantageously formed by the already mentioned sealing devices  149 . The latter are described in more detail with the aid of FIG.  8 . They each comprise a ring  200 , which is axially movable in a bush  202 , a sealing ring  204  sealing the ring  200  in relation to the bush  202 . The bush  202  is mounted on the connection plate  141 , and the connection piece  144  (or  148 ) is connected with a seal to the bush  202 . A spring  206 , which forces the ring  200  in the direction of the connection plate  141 , is arranged in the bush  202 , a shoulder area  208  on the ring  200  fixing an end position of the ring, in which the front end of the ring  200  projects with a sealing face  210  from the connection plate  141 . Hence when the mould  114  is inserted in the bearing  138 , the connection plate  189  of the mould  114  first comes into contact with the sealing faces  210  of the two sealing devices  149 . The rings  200  are pressed against the springs  206  in their bushes  202 , until the connection plate  189  rests on its seat on the connection plate  141 . The springs  206  pretensioned in this way thus ensure an initial contact pressure of the sealing faces  210  on the opposite sealing faces on the connection plate  189 . When the cooling system is operated, the cooling medium under pressure flows through the bush  202 . It generates an additional hydrostatic contact pressure by applying pressure to the rear end face  212  of the ring  200 . 
     The cooling circuit of the mould  114  is indicated by arrows in FIG. 4, as in FIG.  1 . It is pointed out that the cooling circuit of the mould  114  suspended in the vibrating device  112  is essentially identical with the cooling circuit of the mould  14  suspended in the vibrating device  12  in FIG.  1 . 
     It should finally be noted that in the device  110  the mould  114  can be introduced laterally into the vibrating device  112 . Centering means, e.g. centering pins  220  and centering holes  222 , permit simple centering of the mould on the bearing  138 . The oscillating lever  124  could, of course, also be designed like the oscillating lever  24 , i.e. with an end swivelling axis, which would permit more compact design of the equipment  110 . However, with this alternative embodiment the end drive would make the lateral introduction of the mould  114  into the vibrating device more difficult. 
     In the present specification the invention has been described, for example, with a mould  144 ,  114  with a casting pipe. However, it is clear to the expert that the invention can also be constructed with plate moulds.