LU81716A1 - SLIDING DOOR VALVE - Google Patents

Abstract

A sliding gate valve of the type in which refractory gates (17, 17') are sequentially disposed in operative position beneath the pour opening from a teeming vessel, such as a tundish, is effective to throttle the metal flow stream from the vessel. Means (84) for positioning the gates in order to control the degree of throttling of the flow stream are independent from the means (74) for disposing the gates in their working position within the valve mechanism whereby the flow stream can be terminated without adjusting the throttling configuration of the valve. Means are provided, when the valve employs a pour tube (19) attachment, for selectively changing gates and pour tubes in unison, or independently from one another. The valve mechanism and its replaceable refractory components are designed for the supply of fluids for cooling these members and for the injection of inert gas to stir molten metal in the flow passage during holding periods. <IMAGE>

Description

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The present invention relates to a sliding stop valve,

The request from RFA, O.S. No. 2746265 describes a sliding shut-off valve device for use on ladles of molten metal 5, presenting the possibility of throttling the flow of molten metal which passes through the valve. This valve is of the type described in the reissue in the United States of Patent No. 27,237, in which refractory sliding valve doors, doors which are either solid, non-perforated or perforated are arranged in relation to the opening of pouring the OJ ladle so as to be able to start or stop the flow of molten metal. The flow passing through the valve can only be regulated by replacing the sliding door in service with another whose opening has a different diameter, which therefore prohibits the possibility of varying the flow rates according to a continuously variable range. In the aforementioned throttle valve, the regulation of the flow rate can be done by adjusting the position of the opening of the sliding door relative to the pouring opening of the ladle. This characteristic of this throttle valve device makes it possible to modify the metal flow rates without the need to change the sliding doors, which results in a significant reduction in the number of sliding doors 20 and the corresponding costs, necessary for valve operation.

Although this sliding door valve device according to German publication n ° 2746265 represents a significant improvement compared to sliding door valves according to the prior art, it nevertheless has certain disadvantages, Mainly the configuration of the> 25 valve devices imposes certain restrictions on the stroke concerning the movement of the sliding door for throttling and thereby prevents the metal flow from being able to vary continuously between its fully open position and its fully closed position without increasing the size and cost of the valve mechanism at the beyond the limits corresponding to a commercial possibility. This deficiency in the valve makes it necessary to change the sliding doors to allow the flow to be controlled over the extremely low flow ranges and to cut off this flow.

In addition, to be able to avoid solidification of the metal in the ladle opening, it is necessary to place a sliding door 35 having a permeable plug next to the opening to allow the injection of an inert gas. , which requires the expense of additional sliding doors for this purpose, In addition, the valve allows the change of pouring tubes only in conjunction with the replacement of the sliding door which has an orifice with a full sliding door "2 in the purpose of stopping the flow of molten metal before being able to make a change of pouring tube. Another disadvantage of this valve is its inability to positively ensure the alignment of a sliding door which comes after that which is in useful position in the valve to allow a rapid and efficient change of the sliding door,

Consequently, the object of the invention is, in one of the aspects, an improved organization of a sliding door valve of the type in which successive sliding doors can be placed one after the other with respect to the The opening of a ladle and in which the sliding door can throttle the flow of metal from the ladle over a continuously variable range between the fully open condition of the valve and the fully closed condition.

In addition, the invention provides an improvement over the valves corresponding to the previous technique, of the type described, in that means are described which allow the throttling to occur over the entire range of flow rate of the metal without requiring changing sliding doors, The organization of the sliding door valve is therefore characterized by its ability to quickly introduce a solid door therein when it is desired to stop a flow of metal for safety or other reasons and by its ability to change the pouring tubes either in conjunction with or independently of changing the sliding door.

Another characteristic of the invention is the use of a sliding door of a particular configuration which allows its rapid introduction into a useful, sealed position, between the upper valve plate and the support plate of the pouring tube, without risk. to damage one or the other of these refractory elements.

Another characteristic of the invention consists of an upper plate of a particular configuration which allows the efficient distribution of an injection of inert gas into the pouring opening of the bag when the valve is in its closed condition, the shape of this upper plate allowing its manufacture by conventional refractory forming methods without requiring costly machining.

Yet another feature of the invention is to provide means for efficiently supplying cooling air to the parts of the valve which are most sensitive to a high temperature atmosphere, including the sealing springs and the refractory parts. forming the valve opening, which reduces the thermal deterioration of these parts, 40 Other characteristics and advantages of the invention will be better understood on reading the description which follows of an example and with reference to the accompanying drawings, in which;

Figure 1 is a vertical section of the sliding door valve of the invention, Figure 2 is a vertical section taken along line 2-2 of Figure 1,

Figure 3 is a plan view taken along line 3-3 of Figure 1,

FIG. 4 is a partially cut perspective representation of the mounting plate embodied in the invention, showing the paths of the cooling air and the inert gas through this plate,

Figure 5 is a partially cut perspective representation of the upper plate embodied in the invention,

Figure 6 is a plan view of the sliding door constructed according to the invention, Figure 7 is a perspective view of the sliding door of Figure 6,

FIG. 8 is a perspective view taken from above of the structure of the valve frame of the invention, before mounting and,

Figure 9 is a perspective view taken from below of the structure of the valve frame of Figure 8, 2o Figures 1 and 2 show a sliding door valve device 10 suitable for installation in useful connection with the pouring opening 12 of the lining 14 of a pouring container 16, p, e, a ladle or the like, for pouring molten metal into the mold of a continuous casting (not shown), The casting is controlled by 25 the operation of refractory sliding doors or plates, which can be with orifice as shown in 17 in Figures 2, 6 and 7, or solid as shown in 17 'in Figure 1, relative to an upper refractory plate 18, The device 10 also includes a replaceable pouring tube 19 forming an extension of the valve to conduct the jet of molten metal 30 from the casting into the casting mold. The valve device 10 is suitable for mounting on the pocket 16 by means of threaded connectors 20 which extend through the holes 21 of the frame 22 to fix it to the mounting plate 23 which, in turn, is fixed to the pocket by means of bolts (not 3 shown) connected to a grooved plate 24 located under the pocket lining 35 14. A mattress 26, thermally insulating, made of asbestos or the like, can be interposed between the mounting plate 23 and pocket 16

As best shown in Figure 4, the mounting plate 23 is a generally flat metal plate having a central opening 28 for receiving the lower end 30 of the refractory material 40 which forms the pouring opening of the ladle 12, La upper surface of the mounting plate 23 comprises, along its lateral edges, housings 31 which communicate with the bolt holes 32 to receive the connectors 218 and their associated nuts 34,

The mounting plate 23 has a number of internal fluid passages 5 for supplying the cooling air and the inert gas during the valve operating periods. A first passage 36, concentric with the central opening 28, is defined by a recess formed in the wall of the opening and covered with a ring 38 fixed by welding to the plate to close the passage sealingly. In addition, the plate has a pair 10 of elongated passages 40 and 42 extending from one edge to the other on three sides of the plate and terminating in downwardly directed discharge orifices 44 to provide the cooling air to the valve springs as described more fully below. An air inlet port 46 is provided on one side of the plate for supplying cooling air to the fluid passages 36 and 40, 42, which, as indicated by arrows 48, are connected in series, which means that the cooling air is first brought into the annular passage 36, then, in opposite directions, through the passages 40, 42, before being evacuated by the orifices 44,

There is also provided in the mounting plate 23 an elongated passage 50 which communicates at one of these ends with an inlet opening 54 on one face of the plate to allow it to be connected to a source of inert gas and , at its other end, communicates with a discharge opening 52 directed downwards and adapted to communicate with gas supply means in the upper valve plate 18 as described below,

The valve frame 22, essentially formed from a molded and machined metal part, stiffened by ribs 56, is best seen by referring in particular to Figures 8 and 9, This frame 22 contains the operating parts of the valve device and is adapted to be fixed 30 to the mounting plate 23 or to be removed therefrom, in the form of a mounted assembly, by means of the connectors 218. The chassis 22 comprises three main sections, generally identified in FIG. 3 as plate loading section 58, useful section 60 and plate discharge section 62. Next to section 58 plate support, is fixed to the frame 35 22, by means of connectors (not shown) which can be '' engage in threaded holes 64 (Figure 8), a gusset 66 allowing the mounting of the supply motor 68, This supply motor 68 comprises a cylinder 70 maneuvered by a fluid and which comprises a reciprocating piston fixed to a piston rod 72 and at a pusher 74, A second set of motors, 40 called "throttle motors" are fixed to the chassis 22 at the side of the useful section i 5 ’60 of this chassis. These motors 76 act alternately and are operated independently of the supply motor 68. They each comprise an operating cylinder 78 mounted on the chassis by means of a gusset 80 fixed to the side wall of the chassis by means of connectors which can be s 'Engage 5 in the holes 82, The cylinders 78 each include a reciprocating piston whose piston rod 83 is fixed I a connecting spacer 86, which extends laterally, and connects the sliding pins 88 that openings 90 in the side wall of the chassis houses and guides and to which are fixed the throttle rails 84 and 84 'which operate to move a sliding plate placed in the useful section 60 of the chassis.

The rail 84 'is shorter than that of the rail 84 to adapt to the passage of the plate through the support section 58 of the chassis.

The interior of the chassis 22 is designed to define communication paths for the sliding plates 17 or 17 'and the neck tubes 15 between the respective chassis sections 58, 60 and 62, The support section 58 of the chassis 22 , described here, is defined by guide paths 92 and 94 which extend laterally and are adapted to the passage of the sliding plates 17 and 17 'and of the pouring tube 19 respectively. The guideway 92 is vertically spaced from the guideway 94 by the slide rails 96 which extend on either side and serve as support for the sliding plates housed in the valve, The lower part of the guideway 94 is defined by a similar set of sliding rails 98 which support the pouring tubes 19 to allow them to be put in place. Stop rails 99 along the upper part of the chassis in this section serve to vertically position a sliding plate 17 when it moves from the loading section 58 of the valve to the useful section 60 of this valve. .

It will be assumed that the chassis 22, as described in FIGS. 8 and 9, is suitable for being able to introduce therein a sliding plate or a pouring tube 30 either by the right side or by the left side, because it is provided identical guide tracks 92 'and 94' on the opposite side of the chassis. If the guide paths 92 and 94 are chosen to be used, the other guide paths marked as being 92 ′ and 94 ′, on the opposite side of the frame, are closed by means of a filling piece 100 which includes 35 a support plate 102 which can be connected by thread to the chassis 22 by the holes 104 (Figure 8) and stop plates 106 and 108, vertically spaced from each other, which fill the guide tracks 92 ′ and 94 ′, effectively prohibiting the displacement of a pouring tube beyond its desired position next to the pusher 74, Of course it is easy to load the chassis from the opposite side by simply moving the part from "6 < • filling 100 by leaving it from the guide paths 92 ′ and 94 * and by bringing it to the opposite side of the chassis where it will fill the guide paths 92 and 94.

The useful section 60 of the chassis 22 has a tangential rec-5 opening 110 in its upper surface to receive a fixed refractory upper plate 18 whose central orifice 112 aligns with the pouring opening 12 of the ladle and defines the arrival on valve 10,

The chassis 22 comprises, located below the opening 110 and at a certain vertical distance from this opening, lower fabrics 10 114, placed opposite one another and which collaborate with the upper wall of the chassis to define a cavity 115, These fabrics 114 have threaded holes 116, spaced laterally from one another, and receiving connectors 118 to allow the mounting of a series of rocker arms 120 stressed by springs and which function to maintain the pouring tube 15 19, the sliding plate 17 or 17 ′ and the upper plate 18 in tight surface-to-surface relationship. The rocker arms 120 pivot on grains 122 held by connectors 118 and are biased by springs by means of head pins 124 mounted, with the possibility of displacement, in the holes 126 of the chassis. The holes 126 are cut at their upper end at 127 to give seats for the spindle heads 128 and for the springs 130 which are compressed between the spindle heads and the surface of the mounting plate 23 which faces.

As indicated in FIG. 2, the holes 126 of the chassis 22 are provided to communicate with the orifices 44 of the mounting plate 23, this 25 'which means that the cooling air is supplied to prevent overheating of the springs 130, It is desirable that the orifices 44 include evacuation orifices 132 making it possible to efficiently distribute the cooling air over the respective springs,

The opposite walls of the frame of the valve 122, near the useful section 60, have pairs of aligned holes, spaced vertically from one another and marked respectively as 196 and 198. Each pair of aligned holes is provided for receive a stop pin 200 which can be selectively placed and which passes through the respective paths of the sliding plate or of the pouring tube and which is in service during the plate changing procedure to prevent movement of either the plate sliding 17 either from the pouring tube 19 when it is desired to replace the other of these two parts, Similar holes 196 ′ are provided in the rails 84 and 84 ′ to allow the passage of the stop pin 200 through these rooms. If one wishes to carry out the simultaneous replacement at the 40 times of the sliding plate 17 and the pouring tube, one removes the pin 7 4 4 'stop 200 of the chassis completely, which leaves the two free paths of, all obstacle, Under normal operating conditions, the stop pin 200 is housed in the lower hole pair 198 to leave the path of the sliding plate free of any obstacle so as to allow the flow of molten metal to be stopped quickly. as we will describe below,

The discharge section 62 of the chassis 22 is formed by guide paths 134 and 136, spaced vertically from one another and which open at the end of the chassis, The guide paths 134 and 136 are defined by stepped shoulders 138 and 139 formed in the longitudinal extensions of the lower fabrics 114 and are designed to guide in their sliding the sliding plates 17 and 17 'and the pouring tube 19 respectively from their positions in the useful section 60 of the valve to the evacuation point as indicated below.

As best seen in Figure 3, the strut rails-15 84 and 84 'are arranged in the frame 22 substantially at the same level as the guide path 92 supporting the sliding plate. The rail 84 is longer than that of the rail 84 ', and extends substantially over the entire length of the interior of the chassis. The rail 84 'on its side is shorter than the rail 84 by a certain value to allow the passage of the sliding plate 17 from the guide path 92 in a position which corresponds to the pusher 74 when these parts are loaded. In addition, the rail 84 comprises, along the part of its length which faces the guide path 92, a number of magnets 142, longitudinally spaced from one another and represented here in the form of six magnets permanent with four blades, the function of which is to prevent the sliding plate 17 or 17 'once in its "ready to operate" position, described below, from leaving the rail 84 when it is moved during the execution of the valve throttling function.

The sliding plates 17, 17 ', the upper plate 18 and 30 the pouring tube 19 of the valve device 10 essentially each comprise a refractory material housed in a metal frame, The pouring tube 19 envisaged for use in the device described is essentially conventional construction and consists of an elongated cylindrical tube 144 with axial opening 145, The tube 144 has a length which allows its lower end to extend into a casting mold or the like (not shown). The upper end of the tube 144 is designed to be received in a housing 144 of a lower surface of a rectangular refractory plate, generally flat, called the tube support plate 148, This plate 148 has a through opening 149 coaxial with the opening of the 40 tube 145 and is housed, on the portion seen from its underside and on its “8 peripheral faces, in a metal casing 150, as shown in, the FIGURE, a mortar cement is used to seal the joint between 1 'upper end of the tube 144 and the support plate 148 and to fix the support plate inside its metal casing, The metal casing may be provided with a suitable skirt 152 which serves to protect the mortar joint and to stiffen the lower surface of the envelope, a heat-resistant material such as an asbestos cable (not shown) can be used to fill the space 153 which is between the skirt and the tube. A second fixing can be obtained between the tube 144 and the support plate 10 by providing a collar 154 which defines a shoulder 156 next to the upper end of the tube to engage a retaining ring 158 fixed therein, removably to the 'metal casing 150 by threaded flanges or the like, (not shown). Preferably the openings 145 of the pouring tube 144 and the openings 149 of the plate 148 have a diameter slightly greater than the orifices of the sliding plate to allow the flow of metal through this passage when the valve is throttled for the put in a fully closed situation.

Figures 1, 2 and 5 show the entire upper plate 18 of the device provided. This assembly 18 comprises a rectangular rectangular plate 160 fixed by mortar in a metal casing 162. of generally enclosed section of L and which extends on the peripheral sides of the plate. The upper surface 164 of this plate 160 extends above the upper edge of the envelope and has a polished finish to ensure smooth surface-to-surface contact with the lower surface of the mounting plate 23 and the trim. refractory 14 of the ladle when the assembly is in the useful position in the valve device. The plate 160 has a through opening 166, stepped and arranged in the axis, to receive a permeable refractory lining 168 which has an axial opening which defines the passage 112 of the flow of molten metal 30 through the plate. The lining 168 has an outer surface 172 stepped in a manner complementary to that of the opening of the plate 166, the outermost stages being adapted to be fixed, using cement, with the corresponding stages of the opening. , but the intermediate stage having a diameter significantly smaller than that of the intermediate stage 35 of the opening. This way an annular passage 174 is defined all around the circumference of the lining 168 making it possible to supply inert gas, through the lining, the passage of the metal flow 112. The metal plate comprises an oblique channel 176 which s opens at the head of the plate at 178 and is placed to communicate with the opening 54 of the lower surface 40 of the mounting plate 23 when the valve is mounted. There is “9 thus a convenient means of supplying inert gas to the passage of metal barrel 112 during the periods when the valve is closed, thereby allowing the metal which is in the passage to be agitated and preventing it does not solidify.

By forming the annular passage in this way, the refractory upper plates 5 thus formed can be manufactured by conventional methods of refractory forming, without requiring costly machining with tools having to fall back or comprise numerous parts.

The sliding plates used in the valve device can be solid or non-perforated like the type shown in 17 'in Figure 1 or can contain a through opening 180 like the type shown in 17 in Figures 2, 6 and 7, On uses solid plates 17 ′ as shown in FIG. 1, to prevent the passage of metal through the valve, while plates 17 with orifice are used when it is desired to pass, by controlling it, the metal in fusion through the valve as described below. The two types of sliding plates 17 and 17 'are produced identically, comprising a refractory plate 182 generally rectangular and slightly longer in the direction of feeding, indicated at F in Figures 6 and 7 than in the direction of l The throttle indicated in T. The plate 182 is fixed by cement in a metal envelope 184 which surrounds the peripheral sides of the plate. The casing 184 has a shoulder 186 in an intermediate position at its upper and lower edges to allow tight contact of the throttle rails 84 and 84 'and a sliding contact of the sliding rails 96 of the loading section 58 of the valve and the shoulders 138 of the discharge section 62 of this valve. The refractory plate 182 has the shape, in 188, of a shoulder which corresponds to that of the envelope.

The lower part of the envelope, identified in 190, has the shape of a curve of larger radius, which provides a surface forming a guide cam to allow pushing, guiding them, above and beyond. from the upper edge of the pouring tube support, the respective sliding plate when it is moved by means of the pusher 64 to bring it into the useful section 60 of the valve, without causing damage to either The lower part of the plate 182, next to the enlarged radius part 190, of this envelope, is conical, as can be seen, so as to provide a larger housing 192 for the mortar between the plate and the metal casing. The role of the mortar bed thus enlarged in this zone of the assembly has the role of damping the movement of the plate when it moves through the support assembly of the tube 19 and when the plate is manipulated by the movable rails 84, 84 'during throttling periods, 40 The sliding plate 17 differs from the sliding plate 10 17' in that the latter is not perforated while the previous one contains an opening 180 for the flow of molten metal, La position of the opening 180 in the refractory plate is located, critically, on the longitudinal axis of the plate but offset from the center of this plate to the left in Figure 2 by a value equal to half of the length of the stroke of the throttle pins 88, which allows the opening 180 to be vertically aligned with the opening of the upper plate 112 thus allowing the total flow of metal through the casting passage when the plate is fully pushed towards the on the right as shown in OJ Figure 2, the rail 84 abuts with the wall 194 of the cavity 115, When the plate 17 is fully pushed to the left and that the rail 84 abuts against the wall 196, the opening 180 is entirely out of alignment with opening 112, which stops the flow of molten metal through the valve. The operation of the throttle motors 76 makes it possible to adjust the position of the opening 180 in the plate 17 at any desired location with respect to the opening of the upper plate 112, intermediate between these positions of total travel from hand to other, which makes it possible to modify the effective dimension of the passage of the flow of molten metal through the valve in order to regulate the flow of molten metal through this valve.

A typical commercial embodiment of the sliding plate 17 is approximately 277 mm in the feed direction F and 328 mm in the throttle direction T, the center of the opening 180, with a diameter of 76.2 mm , being offset from the center of the plate by approximately 44.4 mm, which provides approximately a thickness of 12.7 mm of refractory material between the holes 112 and 180 when the plate 17 is in the closed position.

The operation of the valve device that has just been described 10 is as follows:

The valve frame 22 is fixed to the mounting plate 23 at the bottom of the ladle 16 as shown in Figure 1, the top plate 18, a full sliding plate 17 'and a pouring tube 19 being pre-assembled in the useful section 60 of the valve frame, the flow passage 112 through the upper plate 18 is thus aligned vertically with the casting passage 12 through the lining of the ladle 35 14, when molten metal is deposited in the bag, its passage through the valve is prohibited due to the obstacle to its passage presented by the full sliding plate 17 'which does not allow the flow of metal to pass, During these periods when it is necessary to retain the metal, a inert gas, such as argon or nitrogen, is admitted towards the casting passage 112 40 of the upper plate through the passages 52 of the mounting plate 23 11 "and 176 of the upper plate to reach the annular space 74 near the lining 168 from where it crosses the porous wall of the lining to enter the passage 112. The entry of the inert gas in this way serves to stir the molten metal in the passage where the metal flow is prohibited, and at 5 s' thereby oppose that the metal solidifies, Likewise cooling air is admitted towards the valve by the inlet 46 of the mounting plate 23 from where it flows successively through the annular passage 36 alongside from the lower region of the lining of the ladle 14 to cool the refractory material which is in this region and from there through the passages 40, 42, to escape through the orifices 44 to cool the springs 130,

When the throttling mechanism is arranged so as to place the rails 84 and 84 ′ in the position shown in FIG. 2, the rail 84 abutting the wall of the cavity 196, a sliding plate 17 is manually inserted with orifice in the loading section 58 of the valve, the sliding plate 17 is introduced into the guide path 92, the shoulders 186 of the plate coming into sliding contact on the sliding rails 96. The sliding plate 17 is moved to that the surface of its edge which is in front abuts against the rail 84, 20 then being retained against this rail by the magnets 142, which places the sliding plate 17 in its "ready to operate" position near the pusher 74 of the supply motor 68. Then the supply motor 68 is operated to cause the pusher 74 to move the sliding plate 17 from its "ready" position to bring it into the useful section 60 of the valve frame 25 between the p upper lacquer 18 and the pouring tube 19, while moving the solid plate 17 which slides along the shoulders 138 in the direction of the discharge section 162 from which it leaves the chassis. An effective surface-to-surface seal is provided between the respective plates thanks to the rockers 120 biased by springs, which push the tube-holder plate 148 upwards against the sliding plate 17 and the latter, in turn, towards the high against the upper plate 18, Due to the existence of an enlarged radius 190 on the casing 184 of the sliding plate 17, the plate is guided in its movement beyond the edge which faces it, of the support plate 148 of the pouring tube biased by a spring, without damaging this plate, the supply motor 68 then operates in the opposite direction to bring the pusher 74 back to the position shown in FIG. 1, after which, for safety, a full sliding plate 17 ′ is introduced, as shown in FIG. 3, in the “ready” position in the valve frame 22 in the same manner as described above 40 in connection with the introduction of the plate sliding 17.

* 12

When it is desired to start the passage of the flow of molten metal through the valve, the flow of inert gas is stopped in the direction of passage 112 and the throttle motors 76, which operate in coincidence, are operated to move the rails 84, 84 ', and the sliding plate 17 which they hold, on the side of the cavity 115, Normally the motors 76 are maneuvered to move the rails 84, 84', so as to place the rail 84 ' in abutment of the wall 194 of the cavity 115, which places the orifice 180 of the sliding plate 17 in axial alignment with the opening 112 of the upper plate 18, This defines the position 10 "fully open" of the valve. As a variant, however, it will be admitted that if it is desired to have a flow rate of molten metal less than the total flow rate, the throttle motors can be controlled so as to place the sliding plate 17 in any intermediate position between its "fully open" positions. "and" fully closed "so as to obtain the desired intermediate flow rate. In addition, during casting, the position of the sliding plate can be modified, either by increasing or decreasing the flow of molten metal through the valve, as desired, by controlling the operation of the throttle motors 76 which cause the throttling movement of the sliding plate 17 and its orifice 180 relative to the opening of 2o casting 112 of the upper plate.

The invention allows rapid replacement of both the sliding plate 17 and the pouring tube 19 either separately or together. If it is desired to replace a worn sliding plate 17, the stop pin 200 is introduced into the holes 198 of the valve frame 23 to prevent movement of the pouring tube. The solid plate 17 'is removed from its "ready" position near the pusher 74 and a replacement sliding plate 17 is inserted in its place. Then the supply motor 70 is operated to move the replacement plate into the useful section 60 of the valve while evacuating the used plate through the evacuation opening 62, 30 This procedure can be carried out with the rails d 'throttle 84 and 84' arranged in any lateral position on the useful section 60 since the replacement plate 17 is held on the rail 84 by the magnets 142. Therefore, once placed in the useful section 60, the plate Replacement 17 will take the same throttling position as the used plate 35 that it replaces.

If it is desired to replace a pouring tube 19, the throttle rails 84, 84 ′ are maneuvered, using throttle motors 76 to move the sliding plate 17 to its fully closed position shown in the Figure 2 and remove the solid safety plate 17 'from the ΔΠ valve frame. The stop pin 200 is then taken out of the holes 198 and * 13 * is introduced into the holes 196, 196 ′ to prevent movement of the sliding plate in service 17, The replacement pouring tube 19 is introduced manually by the guide path 94 of the loading section 58 of the frame of the valve 23 to bring it to a position close to the pusher 5 74, after which the supply motor 70 is maneuvered to move the pouring tube from replacement 19 to bring it into its service position next to the sliding plate 17 in section 60, while expelling the used pouring tube through the guide path 136 of the discharge section 62.

10 If, as a variant, it is desired to change both a smoothing plate 17 and a pouring tube 19, it is necessary to operate the throttling motors 76 to move the rails 84, 84 * and to bring the sliding plate in service 17 to its fully closed position then remove the stop pin 200 from the valve frame. The replacement sliding plate 17 and the pouring tube 19 are introduced by the guide tracks 92 and 94 respectively in the loading section 58 near their "ready" positions next to the pusher 74, by operating the feed motor 68 , the replacement sliding plate and the replacement pouring tube are moved simultaneously to bring them into position in the useful section 60 while expelling the corresponding worn parts by the guide tracks 134 and 136 from the discharge section 62.

An important characteristic of the valve device described here is its ability to rapidly stop the flow of molten metal which passes through the valve and this independently of its throttling function. This characteristic is obtained by the fact that the operation of the motor supply 68 which performs the replacement of the valve plate is completely independent of that of the throttle motors 76 and of the fact that the sliding plate 17 can be changed independently of the throttling position of the sliding plate service located in section 60 of the valve, 30 Consequently, during a normal operation of operation of the valve, a full sliding plate 17 ′ is preferably kept in the "ready" position next to the pusher 74, This plate , like all the plates which are in the "ready" position is held against the rails 84 by the magnets 142 and is thus forced to move laterally back and forth 35 with the plate sliding in service 17, thus ensuring that the latter is always aligned longitudinally with the latter, If, for any reason, it becomes necessary to quickly stop the flow of molten metal, for example due to a malfunction of the molding process, it suffices to maneuver the feed motor 68 to replace the sliding door 17, with orifice, which is in service, by the solid door 17 ′, On * 14 "will appreciate the advantage of this characteristic if it is considered that a change of plate can be carried out by the supply motor in less than 0.2 seconds, whereas on the contrary it takes a period of time of approximately 2 seconds to move the sliding plate in service from its fully open position 5 to its fully closed position, by means of the throttle motors 76,

Of course various modifications can be made by those skilled in the art to the devices which have just been described solely by way of non-limiting example, without departing from the scope of the invention,

Claims (20)

1, Door for controlling in a valve the flow of liquid metal from the pouring opening of a ladle, comprising a generally rectangular refractory body with a longitudinal axis and a lateral axis which is transverse to it and an opening , through the said 5 body, which defines a metal flow orifice, characterized in that the said orifice is disposed on the lateral axis of the said door and offset with respect to the said longitudinal axis, 2, door according to claim 1, characterized in that the value of said offset is greater than the radius of said orifice. ] 0 3. Door according to any one of claims 1 or 2, charac- * terized by a metallic envelope which surrounds the cStés of said refractory body and by shoulders formed in said metallic envelope on all sides of said body and which define surfaces for the guided movement of said door in directions parallel both to its longitudinal axis and to its lateral axis, 4, door according to claim 3, characterized in that the said envelope comprises a part which forms a cam surface in a convex arc, below the said shoulders, at least along the lateral sides of the said body, 5, door according to claim 4, characterized in that the arc forming surface of said casing is located at a certain distance from said refractory body and in that a mortar mattress fills' the space between the two . 6, valve allowing the control of the flow of liquid metal coming from the pouring opening of a ladle, comprising a frame for connection to said ladle and a hollow interior, an upper plate fixedly mounted on said frame and having a through opening allowing the fluid to communicate with the pouring opening of the ladle, rails which carry the opposite door 30 mounted in said frame to carry, with the possibility of sliding, refractory doors to ensure a successive movement through said chassis along a path comprising a door loading section, a useful section and a door discharge section, at least one refractory door mounted, so as to ensure its sliding , on said rails, said door having a refractory body of generally rectangular shape whose longitudinal axis is aligned with said rails and whose lateral axis is transverse to it rsal, and ^ through the said body, an opening which defines a metal flow orifice to align with the said "* 16 When the upper plate opens, the first displacement means fixed * to the said chassis and capable of maneuver to move the refractory doors successively along the said rails and second displacement means, capable of operating independently of the said first displacement means and. 5 functionally connected to said rails for moving said door along a second path transverse to said frame and making it possible to vary the degree of alignment of the orifice of the door with respect to said opening of the upper plate between a position where they are aligned coaxially with each other and a position where they are out of alignment, characterized in that said orifice is disposed on the lateral axis of said door, offset by in relation to said longitudinal axis, 7, valve according to claim 6, wherein the frame has a lateral opening communicating with the door loading section to allow lateral introduction of the doors, the adjacent rail 15. said lateral opening being interrupted by said opening and the rail opposite to said lateral opening extending substantially over all of these three said sections of the chassis, characterized in that said opposite rail has means for holding a door on the rails in the loading section of said chassis. 2o 8 · valve according to claim 7, characterized in that said holding means comprise at least one magnet, 9. Valve according to any one of claims 6 to 8, characterized by rails supporting the pouring tube arranged in said frame. , below and extending substantially like the said door support rails 25 and a pouring tube assembly comprising a tube support plate which can engage in the rails to allow sliding movement along these rails, 10. Valve according to claim 9, characterized in that the said first displacement means comprise operational means for displacing the said set of pouring tube along its rails,. 11, valve according to claim 10, characterized by means for selectively prohibiting the movement of the doors and the pouring tube to allow said door moving means to move said doors and said pouring tubes individually or together. 35 12, valve according to claim 11, characterized in that the said prohibition means comprise a stop pin, which can be selectively positioned either in a position where it crosses the path of the doors or in a position where it crosses the path of the pouring tube. 13, valve according to any one of claims 9 to 12, / ιΛ oaa an λα au a 1 ac ► iik Δ A Δ ΛΑ111 O 3 AAmnAvl · αΚοαιιΛ 1IHÛ 601 * 1 A%; 17 "of fixed rocker arms, with the possibility of tumbling, to said chassis, and one of the ends of which can engage in said support plate for the pouring tube and springs housed in said chassis and providing an upward bias at the said end of each of the said rockers, 5 14, A valve according to claim 13, comprising a valve mounting plate for interposition between said frame and said ladle to form a connection between its two parts, characterized in that the mounting plate comprises means for providing coolant to the orifices of said chassis which are in relation to said springs, 10 15, valve according to any one of claims 6a 14, characterized in that said upper plate comprises an annular passage disposed concentrically with respect to the through opening and means * for supplying an inert gas in said passage, 16, valve according to claim 15, characterized in that the through opening in said top plate has axially spaced stages and of progressively increasing diameter going from one end to the other of said opening and receives a porous plug having an opening and the external surface of which has the form of axially spaced stages and whose diameter decreases progressively from one end to the other of said plug, the stages on the end side of said plug being cemented with the corresponding stages of the axial opening of said body, and the stage of said plug which is intermediate between said stages on the end side having a diameter smaller than that of the corresponding stage of axial opening, thus defining the says annular passage, 2 ”5 17. Valve according to claim 16, characterized in that a metal casing is cemented all around the periphery of said upper plate, 18. Refractory plate for use in a valve for controlling the flow of a liquid metal coming from a ladle, comprising a refractory body with through opening, characterized in that said opening comprises axially spaced stages. one of the other and of progressively increasing diameter going from one of the ends to the other of said opening, and receives a porous plug whose outer surface has the form of axially spaced stages one of the other and gradually decreasing in diameter from one end to the other of said plug, the stages on the end side of said plug being cemented to the corresponding stages of the axial opening of said body and the stage of said plug which is intermediate between the said end side stages having a diameter smaller than that of the corresponding stage of the axial opening so as to define an annular passage. * 18 " 19, valve for controlling the flow of a liquid metal from the pouring opening of a ladle, comprising a connection frame with said ladle and having a hollow interior, also comprising rails for supporting the opposite door mounted in said frame to carry,, 5 with the possibility of sliding, refractory doors thus allowing them to be successively moved through said frame along a path which has a door loading section, a useful section and a door unloading section, first displacement means fixed to said frame and serving to move the refractory doors successively along said rails and second displacement means which can be operated independently of said first means and functionally connected to said rails to move the said door along a second path transverse to the said chassis, thus making it possible to vary the degree of alignment of the orifice of the door with the opening of the said upper plate between a position of alignment coaxial with one another and a position out of alignment with each other, the chassis comprising an opening side communicating with the door loading section thus allowing the lateral introduction of the doors, the rail adjacent to said lateral opening being interrupted by said opening and the rail opposite to said lateral opening extending substantially over the three said chassis sections, characterized by means making it possible to retain a door on said opposite rail in the loading section of said chassis, 20. Valve for controlling the flow of a liquid metal coming from the pouring opening of a ladle, comprising a connection frame 25 with said ladle and having a hollow interior, also comprising support rails for the opposite door mounted in said frame to carry, with the possibility of sliding, refractory doors thus allowing them to be successively moved through said frame along a path which has a door loading section, a useful section and a 30 door unloading section, first displacement means fixed to said frame and serving to move the refractory doors successively along said rails and second displacement means which can be maneuvered independently of said first means and functionally connected to said rails for moving said door along a second path transverse to said chassis, thus making it possible to vary the degree of alignment of the orifice of the door with the opening of said upper plate between a position of coaxial alignment of one with the other and a position out of alignment of one and the other, the valve comprising rails for supporting the pouring tube arranged in the said chassis under and extending 4: i9 »4 substantially in the same way as the said door support rails, and a set of pouring tubes comprising a tube support plate which can come in contact with the rails to allow sliding movement along the rails during the operation of said first displacement means, „5 characterized by means making it possible to selectively prohibit the movement of the doors and of the entire pouring tube to allow said first means for moving the doors to move said doors and the pouring tube assemblies, individually or together. r r