DE2342876A1 - LOCKING VALVE DEVICE FOR CONTINUOUS CASTING KILLS - Google Patents

Description

Gate valve device for continuous casting molds.

The invention relates to improvements in the casting of metals including, for example, steel, aluminum and fiessing, and in this context refers in particular to a gate valve device for continuous casting molds,

In a process for the continuous casting of steel, for example, the steel melt when it emerges from a provided with a bottom pouring ladle or a tundish controlled by a gate valve device in which a gate body is so arranged is that it slides against a stationary orifice plate. Examples of such

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Patent attorneys Dipl.-Ing. Martin Licht, Dipl.-Wirtsch.-Ing. Axel Hansmann, Dipl.-Phys. Sebastian Herrmann Oppenauer BOrOi PATENT ADVOCATE DR. REINHOLD SCHMIDT

- 2 - 234287a

Gate valve devices are disclosed in GB patents 1,093,478 and 1,274,013 and in GB patent application 25 545/72. Reference is made to these examples here. The above publications deal with arrangements in which the slide body can be reciprocated in a straight line is. In an alternative arrangement, the slide can be rotated. This type of slide movement is for example, described in U.S. Patent 3,440,644.

It has been found to be advantageous to press the slide body against the stationary orifice plate with the aid of springs to press to thereby create a resilient seal between the slide body and the orifice plate to accomplish. Furthermore, both the valve body and the orifice plate have proven to be heat-resistant Form body which is enclosed by a thin-walled metal housing, thereby the required mechanical and structural properties in connection with the necessary heat resistance to ensure.

In the operating state, the springs are subject to considerable stresses and, at times, also strong thermal loads. Therefore, there is a risk that the spring weakens in its resilience and fails, whereby the Valve body away from the stationary orifice plate is moved downwards, with the result that molten steel escapes.

The object of the invention is therefore to provide an improved elastic device that for a gate valve device when casting metals

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lets use. This to be created locking slide device should therefore with such an elastic or be equipped with a resilient device. In this context, a metal casting plant is also to be created which has such a gate valve device.

To solve this problem, according to the invention, a Created spring device, which is used in the casting of metals for a gate valve device leaves, and which has two buffer bodies which are resiliently pressed against one another to a locking slide body of the device in sealing contact with a device seat once the device is in operation is. The arrangement is made so that in the event that the spring action between the buffer bodies fails, the relative movement of the body is greatly restricted, thereby resulting in a corresponding restriction of movement of the slider body when it is detached from the seat body to be reached as soon as the device is in operation.

For example, the movement of the slide body directed away from the seat body can be compared to known ones Values to an amount between 0.13 mm and 0.7B millimeters, so limit, for example, about 0.51 mm.

According to the invention, an independent elastic device is also created, which is suitable for a gate valve device can be used in the casting of metals and a) a core body, b) opposite buffer body, the are mounted on the core body in such a way that they can perform a relative movement in the longitudinal direction of the core body, and c) a spring device which acts between the buffer bodies, around them in relation to each other under pressure

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to set and which has a plate spring which is arranged around the core body.

According to the invention, moreover, an elastic one Establishment created for a gate valve device when casting metals can vswenden and two buffer bodies and one between them having spring device located, wherein the buffer body can be resiliently pushed apart by the spring device are to a slide body of the device with a seat body of the device in sealing contact to bring as soon as the device is in operating condition. The spring device has its part a first spring arrangement which, in the operating state of the device, the buffer body normally resiliently pressed apart, as well as a second spring arrangement, which is relaxed as soon as the first spring arrangement Developed spring force, and which also exerts a spring action to the buffer body apart press as soon as the first spring arrangement does not work.

The gate valve device according to the invention thus has a gate valve body, a seat for this gate valve body and an independent, elastic device on, with which the slide body can be pressed against the sealing body in order to make sealing contact with it occur, wherein a spring device is provided, which consists of a plate spring.

In the elastic device used, which consists of two buffer bodies, which relative to each other with elastic Compressive force beaufechlagbai / are to the slide body to bring it into sealing contact with the seat body, one of the buffer bodies is located next to the slide body, while the other is away from him. The one

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Buffer body, which is located next to the valve body, is on the core body on which the two slide bodies are movable relative to one another in the longitudinal direction of the core body are stored, fixed, while the spring device surrounding the core body works between the buffer bodies, to push them apart. The core body extends into a leading away from the slide body Direction against a stop, so that its movement in the event of failure of the spring device is restricted quite considerably, whereby the movement of the slider body in the direction away from the seat body is restricted in a corresponding manner.

The thin-walled metal housing that surrounds a heat-resistant body from which the valve body or the stationary one Orifice plate can exist, has a wall thickness between 2.5 and 3.5 mm, so for example about 3, ο mm. It should be pointed out here that, of course, both parts mentioned, that is to say both the slide body as well as the stationary orifice plate from a heat-resistant Body can exist, which is enclosed by the thin-walled metal housing.

The invention is shown below with reference to the drawing illustrated embodiments explained in more detail. In the Drawing show:

Figure 1 is a sectional side view of the one described here Gate valve or gate valve assembly,

Figure 2 is an enlarged, sectional side view of an elastic device of the arrangement,

Figure 3 shows a first embodiment of the elastic device,

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Figure 4 shows a second embodiment of the elastic device,

Figure 5 shows a third embodiment of the elastic Contraption,

Figure 6 is a sectional view of a conical disc spring,

FIG. 7 a fourth embodiment of the elastic device,

Figure 8 is a sectional view along the line VIII-VIII in Figure 1,

FIG. 9 shows a sectional view along the line IX-IX in FIG. 1, and

FIG. 1o is an exploded perspective view of certain parts of the arrangement from FIG Figure 1 with a toggle mechanism, which is in the released state, and with a locking slide carrier, which is in a hinged, released, vertical position.

The gate valve arrangement shown in FIGS. 1, B, 9 and 1o is shown, can be poured into a continuous casting mold (not shown) or a tundish when casting steel use a continuous caster, the molten steel from one with a bottom pouring opening provided ladle 1o is cast, which has an outer metal housing 11 and a heat-resistant lining 13 having. A nozzle assembly 12 is mounted in the ladle 1o and has a heat-resistant nozzle tube 14 which is carried in refractory blocks 16, 18 and a refractory outer nozzle body 19, which is arranged in a metal bearing plate 2o,

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on the outer metal housing 11 of the ladle 1o is secured by screws 326 (Figure B). A stationary, heat-resistant orifice plate 22 is below attached to the bearing plate 2o and has an opening 24 which is aligned with the nozzle tube 14.

The gate valve assembly is also equipped with a frame 26 which is attached to the bearing plate 2o by a Toggle mechanism 334 is removably attached, as detailed in British Patent Application 2556/72 is shown. A slide carrier 28 is mounted horizontally displaceably in the frame. The horizontal sliding movement of the carrier 2B is effected by a hydraulic cylinder and piston arrangement 29, which is in a console 3o of the frame 26 is mounted. A heat-resistant slider 32 is supported in the carrier 2B and has a Nozzle tube 34 extending downwardly from the stationary plate 22. The nozzle tube 34 is in upper and lower refractory rings 36, 3B. A lower surface 4o of the stationary plate 22 bä. det an upstream seat for the slide 32.

It can be seen that the slide 32 between a closed position, as shown in Figure 1, in which the The nozzle tube 34 is not aligned with the opening 24 and is in an open position, not shown, in which the nozzle tube 34 is aligned with the opening 24 and molten steel flow freely from the ladle 2o and through the nozzle tube 14, the opening 24 and the nozzle tube 34 in the continuous casting mold or the intermediate casting vessel can enter, is movable.

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The slide 32 is supported by several spring devices 42, which are arranged distributed around the nozzle pipe 34 at a distance, pressed against the stationary plate 22, so that it comes into sealing contact with this. There are, for example, between B and 18 spring devices 42 present, wherein 12 are shown in Figure 9, each device 42 acts between the Carrier 28 and the slide 32 and sits in a bore 62 (Figure 2) in the carrier 28t The spring devices 42 are arranged in a certain pattern around the nozzle pipe 34, as can be seen from FIG.

The piston and cylinder assembly 29 includes a hydraulic cylinder 316, which is supplied with hydraulic medium via hydraulic lines 362. Inside the cylinder 316 a piston 363 is journalled and attached to a hollow bumper 365. The bumper 365 extends through a bumper guard 364 and is attached to the slide bracket 28, which in turn is in the Console 3o is attached. An air hose 361 is used to continuously draw air through the hollow bumper 365 to blow through, thereby not only the cylinder 316 but also the carrier 28 and the spring devices 42 to cool. The carrier 28 has for this purpose in its interior has several connected air chambers 375, and the air hose 361, the one with the hollow bumper 317 is connected, there is a constant flow of air to these air chambers 375, whereby the wearer and the spring devices 42 are cooled. The air can be dry or humid, with carbon dioxide as an option Can be used.

The stationary plate 22 sits in a recess present in the bearing plate 2o (FIGS. 1 and 1o) and contains also a central ring groove which is sized so that they

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an annular body 3o8 of the outer nozzle body 19 receives.

The plate 22 has two straight, parallel sides which are connected to one another by semicircular end parts are, and forms a heat-resistant body 3o9 which is surrounded by a thin-walled steel housing 31o. The heat-resistant body 3o9 is fixed in the case 31o by a thermosetting adhesive. One circular opening 31oa (Figure 1) is provided in the metal housing 1o next to the annular body 3o8, to produce a ceramic joint, it being seen that the housing 31o is the lower surface 4o left uncovered. A putty-like heat-resistant filling compound, such as that in the above British Patent application 34 63o / 72 is described, is filled between the metal housing 31o and the plate 22 and compensates for irregularities. Thus, the heat-resistant body of the stationary plate 22 is enclosed so as to that it is kept in its position in the event of breakage or cracking.

The slider 32 similarly has a heat-resistant body which is supported by the nozzle tube 34 and the Annular bodies 36, 38 is formed. This heat-resistant body has an upper part with straight, parallel lines Sides and semicircular end portions that correspond to the stationary plate 22, as well as a lower, circular, cylindrical section. Here, too, the heat-resistant body is surrounded by a thin-walled steel housing 37o, while the top of the body 36 as well as the bottom of the body 38 and the nozzle tube 34 remain uncovered. The heat-resistant body is in turn fixed in the housing 37o by a thermosetting adhesive, and a putty-like, heat-resistant filler material can be used.

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The nozzle pipe 24 dss slide 32 is made of highly erosion-resistant, heat-resistant material, while the lower ring body 38, which surrounds the nozzle tube 34, is made of heat-resistant material of low conductivity. The upper ring body 36 is in comparison to the material from which the stationary plate 22 is made of an abrasion-resistant, heat-resistant Material.

The highly erosion-resistant, heat-resistant material for example, has a high alumina content, normally in the range between 85 and 95 weight percent. This material has a high density and is fired at a high temperature, the surfaces of such Materials often need to be sanded to give them the exact shape you want. On the other hand, it can refractory material such as that used for blocks 16, 18 and ring body 38, e.g. have a porous structure with a low aluminum oxide content and be castable. Alternatively, IaBt use a fired material. Another alternative for such a material is a castable one Mierial made of sintered silicon oxide.

The surfaces of the body 36 and the stationary orifice plate in sliding contact with one another 22 are ground and polished so that the required sealing properties are obtained.

It can be seen from FIG. 10 that the orifice plate 22

on

in plan view with respect to each of the two mutually perpendicular axes is formed symmetrically. In the same way, the slide 32 is also symmetrical. This ensures that the orifice plate 22 and let the slide 32 turn to make the effects of erosion more even.

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Each spring device 42 (Figure 2) forms an independent unit and consists of opposite upper and lower buffer bodies 44, 46. The upper buffer body 44 is connected to the metal housing 37o of the Slider body 38 in contact, while the lower buffer body 36, which is annular, of located away from the valve body 3B and with a horizontal, machined ring shoulder is in contact, which is formed in the bore 62 of the slide carrier 28. The buffer body 44 is on a vertical core body 5o böfösoigt by a screw 52, which is in a threaded hole 54 in the core body 5o is screwed in. Alternatively, the buffer body 44 can be inseparable from the core body 5o Form unity. The annular buffer body 46 is freely movable on the core body 5o, which extends through the annular buffer body 46 down into a recess 56 below, below the shoulder 48 lies. In an annular groove 6o in the core body 5o sits a snap ring 58, which serves to to retain the annular buffer body 46 prior to installing the spring device 42 in the carrier 28. Man recognizes that the buffer body 44, 46 are attached to the core body 5o so that they extend in the longitudinal direction of the core body 5o can move relative to each other.

An elastic Q-ring 64 is seated in an annular groove 66 in the buffer body 46 and serves to fix the spring device 42 in the bore 62.

A sleeve 68 is on the core body 5o between the Buffer bodies 44, 46 slidably mounted. An upper end part of the sleeve 68 is provided with an annular shoulder 7o, and the lower end portion of the sleeve 68 has an annular shoulder 72 on. The upper end portion of the sleeve 68 is seated in a

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in the buffer body 44 existing recess 68a. One The first spring arrangement, consisting of six conical disc springs 74, surrounds the sleeve 68 and sits on the annular shoulder 7o and is in engagement with the buffer body 44. Similarly, a second spring arrangement is provided, consisting of two conical disc springs 76, which surround the sleeve 68, but sit on the shoulder 72 and are in contact with the buffer body 46. The disc springs 74 are connected in series, while the disc springs 76 are connected in parallel.

An example of a conical disc spring, often also known as a Belleville spring, is shown in FIG. The plate spring of Figure 6 consists of a metal disc with a central bore Bo on which towards a frustoconical side wall 82 converges. The outer circumference 84 of the disk is circular and cylindrical and arranged coaxially to the bore 8o. If several such Belleville washers are stored coaxially in series, i.e. when the adjacent discs are opposite to each other, so the spring characteristics of the springs connected in series are the same as for a single leaf spring. if on the other hand, several leaf springs / are connected in parallel coaxially to one another, i.e. if all discs are in the same Converge direction, the load required for a given deflection is multiplied by the number of leaf springs connected in parallel. Consequently is the parallel arrangement of the leaf springs 76 opposite the series-connected arrangement of the springs 74 is preferred.

During normal operation of the spring device 42, the springs are 76 in parallel, which experience a greater deflection or deflection than the springs connected in series 74, substantially relaxed, and the sleeve 6Θ extends in the longitudinal direction of the core body 5o against the buffer body 46, so that between a lower end face of the

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Sleeve Ββ and the buffer body 46 a small gap Boa is left. Thus, the leaf springs 74 work by resiliently yielding and between the sleeve ΒΘ and the Buffer body 44 act to press this buffer body up against the gate valve body 3B. Here too a small gap 82a is again left between an upper end face of the sleeve 66 and the buffer body 44. The actual width of the gap B2a varies depending on the accuracy of manufacturing the slider and associated parts, but the tolerance is no greater than about 0.254 millimeters. '

Taller feathers fail under the influence of heat and others Loads usually not as light as coil springs, but if the series-connected one fails it will move Disk springs 74 of the buffer body 44 downwards to close the gap B2a, which results in its downward movement is severely restricted and limited by the width of the gap 82a and the movement of the locking slide 32 away from the stationary orifice plate 22 is therefore correspondingly severely restricted.

In the event that too large manufacturing tolerances for Close the gap 82a against the force emanating from the serially connected plate springs 74, without these springs failing, the springs 44 are put out of operation, and the springs 76 take up their suspension work to with the opposite to those connected in series To work springs 74 double load deflection and thereby press the slide resiliently against the stationary plates 22.

Ea is very likely that the springs 76 fail, however, in this case the resulting downward movement of the sleeve 68 is determined by the width of the gap 8oa, which, for example, is not greater than

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8 thousandths of a centimeter. So it will just in case failure of the series springs 74 and springs 76 reduced the total downward movement to about 12 thousandths Limited centimeters. When the slide 32 moves away from the stationary orifice plate 22, which is only 0.254 or at most 0.76 millimeters

the risk of a large amount of molten metal leaking out is minimal.

It goes without saying that a failure of the leaf springs 74 connected in series is not necessarily in any case always means a failure of the entire spring arrangement 74 * it is rather possible that one of these Springs fail while the others stay in tact, a fact that is also true of leaf springs 76.

In another embodiment, the leaf springs 76 are omitted, since in this case the sleeve 68 is permanent is in contact with the buffer body 46. Failure of the leaf springs 74 connected in series will result in this Trap still caught, but manufacturing tolerances that are too large are no longer covered so well.

In another embodiment, between the buffer body 46 and the leaf springs 76 placed thin washers to prevent further possible downward movement of the sleeve 68 in the event of failure of the springs 76 to limit.

The first modified spring device shown in Figure 3 is that shown in Figure 2 in many ways Similar in respect and is therefore only described here insofar as it differs from this one. The spring device of Figure 3 has an upper and lower buffer body 144, 146 and a core body 15o. One Sleeve 168 is mounted on core body 15o. A single one

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Disk spring 19o acts between the sleeve 166 and the buffer body146 by interacting with these two bodies is in contact, and performs the same function as the springs 76 in Figure 2. A screw spring 192 surrounds diB sleeve 16Θ and acts between the disc spring 19Q and the buffer body 144, with which it is also in contact, where it fulfills the same function like the serially connected disc springs 74 from FIG.

The second modified spring device, which is shown in FIG. 4, again resembles that of FIG in many ways and is therefore also only described insofar as it differs from this. The spring device shown in Figure 4 has buffer bodies 244 and 246 and a core body 25o. A coil spring 294 acts between the buffer bodies 244, 246 and is in contact with them. This coil spring has closely spaced turns 296, and for the In the event of failure of the spring, the downward movement of the buffer body 244 is due to the small distance between them Windings severely restricted.

The third modified spring device shown in Figure 5 is similar in some respects to the device shown in Figure 4 and is therefore only with regard to the existing differences. This third spring device has an upper and a lower buffer body 444, 446, a core body 45o and a coil spring 494, as shown in FIG is, however, the coil spring 494 has a normal winding pitch. The coil spring 494 is of surrounded by a relatively strong band spring 5oo, which consists of a spiral band between the buffer bodies 444, 446 is arranged so that it is only in the event of an abnormal downward movement of the upper buffer

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body is put into operation. There is normally a gap between the ribbon spring and the buffer body 444 462a present. In the case of a gate valve arrangement, in If such band springs are installed, it may be necessary to use the spring devices with band springs, which are only located at certain points around the nozzle tube of the slide, while known spring devices to be used at the abring places. For example, contain from a total number of 8-16 spring devices only 4 band springs of the type described.

A fourth modified spring device is shown in FIG. Again, it resembles the device of Figure 4 in some respects and is therefore only referred to in relation to the differences present with this device described. The fourth modified spring device has an upper and a lower buffer body 544, 546, a core body 55o and a helical spring 594, the latter again having a normal winding spacing owns. However, the core body 55o extends in a direction away from the slider body 32, in the existing in the carrier 28 recess 56 into it, against a stop device which is of a Bottom wall 56a of the recess 56 is formed so that a is arranged under the end face of the core body 55o at a small distance from the bottom wall 56a of the recess 56. The downward movement of the core body 55o and thus of the buffer body 544 is due to the small width of the gap between the lower end face of the core body 55o and the Bottom wall 56a severely restricted. The width of this gap is, for example, no greater than q.64 or o.76 Millimeter.

The body used for the dehitrile housing Steel is very tough, for example a hot Eawaltter,

: tOä «) 3/081 p

Pickled and oiled stainless steel, which is suitable for drawing. In certain cases, a deep-drawing property or special deep-drawing properties can be specified.

Suitable spring materials for disc springs or ribbon springs that are used at high temperatures can be found in the following information, which is arranged according to the maximum operating temperature is:

18/8 stainless steel * nickel / chrome alloys and Titanium / vanadium alloys.

For example, 1B / B stainless steel can be used up to to about 45o C, while nickel / chromium alloys can be used up to about 600oC.

The disc springs used here are commercially available and range in size between 2.54 and 61 centimeters in diameter, and their thickness varies from 26 SWG to more than 15.9 mm.

Disc springs are manufactured with different spring characteristics that are not necessarily linear, but are, for example, progressive, degressive or vice versa. In the case of the disc springs 76 of be of particular importance.

It is understood that the spring devices described here and those surrounded by the metal housing, heat-resistant Parts of the type described above in slide valve assemblies for tundish vessels or other molten metal receiving containers or ovens can be used, as well as for pouring ladles during continuous pouring of steel.

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Although the invention has been described on a pouring vessel provided with a bottom pouring opening, it is illuminating one that designed according to the invention slide gate assemblies can also be used for other watering vessels

According to a further advantageous embodiment can effect the sliding movement of the carrier 28 by means of a piston and cylinder device mounted on a side wall is attached to the ladle 1o, as shown in US Patent Application 3oo,957.

According to another advantageous embodiment, the heat-resistant ring body 36 corresponds to the orifice plate 22 its shape and its dimensions according to the heat-resistant body 3o9 of the slide 32. In this Trap, an upper end portion of the nozzle tube 34 ends immediately below the ring body 36 and does not extend through the ring body 36.

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Claims (11)

Claims 1. Gate valve device for casting metals, with at least one elastic device, which has two buffer bodies, which are resiliently movable relative to one another, around a slide body bring the device with a seat body of the device in sealing contact, which of a stationary orifice plate, characterized in that in the event of failure the elastic device between the buffer bodies [44, 46) a relative movement of these buffer bodies strongly Luai.! .. üii; sLor is to be in the operating state of the device a corresponding restriction on the movement of the slider body (32) in the direction away from the seat body . 2. Device according to claim 1, characterized by a core body (5o, 51) on which the buffer body (44, 46, 144, 146) in the longitudinal direction of the core body are mounted relatively movably, a spring device (74, 76, 19a, 192) surrounding the dBn core body and the Buffer body pushes apart, and through a sleeve body (68, 168) which slides on the core body (5o, 15o) is mounted and extends in the longitudinal direction of the core body against the buffer body (44, 46, 144, 146), so that the sleeve body (68, 168) the relative movement of the buffer body in the direction of each other for greatly restricts the event of failure of the spring device. 3. Apparatus according to claim 1 or 2, characterized in that the spring device consists of several disc springs (74), which are connected in series, and a plurality of disc springs (76), which are connected in parallel. 4. Apparatus according to claim 1 or 2, characterized in that the spring device consists of a plate spring (19o), which acts between the sleeve body C168) and one of the buffer bodies (146) and with these two Parts is in contact, and a helical spring (192) exists between the plate spring (19o) and acts on the other buffer body (144) and is also in contact with these two parts. 5. Apparatus according to claim 1 or 2, characterized in that the spring device is a helical spring (294) which is in contact with both buffer bodies (244, 246), and that adjacent turns (296) this helical spring have a very small distance from each other, so that the helical spring (294) the relative movement the buffer body (244, 246) towards each other strongly in the event of failure of the spring device limited. 6. Apparatus according to claim 1 or 2, characterized in that the spring device is a helical spring (494), which acts between the buffer bodies (444, 446) and is in contact with these bodies, as well as sine ribbon spring (5oo), which is arranged between the puff bodies and the relative movement of the buffer bodies (444, 446) towards one another in the event of failure the coil spring (494) is severely restricted. 7. Device according to one of claims 1-6, characterized in that the elastic device is an independent Unit is, and that the spring device has at least one plate spring (74, 76, 19o) which the Surrounds core body (5o, 15o). : 3/0816 8. Device according to one of claims 1-7, characterized characterized in that the spring device comprises a first spring arrangement (74, 192, 494) which normally one exerts spring force to the effect that it presses the buffer body apart, and a second spring arrangement (76, 19o, 5oo), which is relaxed as soon as the first spring arrangement develops its spring force, and which, in the event that the first spring arrangement is put out of operation, develops a spring force, to push the buffer bodies apart. 9. The device according to claim 1, characterized in that the elastic device has a core body (55o), on which the buffer body (544, 546) are mounted relatively movably in the longitudinal direction of the core body that the er buffer body (554), which is located next to the locking slide (32) is attached to the core body (55o), and that the core body (55o) is in one direction from the slider body extends away against a stop device (56a) in order in the event of failure of the spring device (594) greatly restricting the movement of the core body, and thus restricting the movement of the seat body accordingly to achieve away-facing movement of the slide body (32), 10. Device according to one of claims 1-9, characterized in that that each slide body (32) and / or the stationary opening plate (22) is a heat-resistant body (34, 36, 38, 3o9), which consists of a thin-walled metal housing C37o, 31o), the wall thickness of which is between 2.5 and 3.5 mm. 11. Device according to one of claims 1 - 1o, characterized in that that each orifice plate (22) and the slide body C32) two straight, parallel sides in plan view which are connected by semicircular end parts, as well as having a central, circular opening, and symmetrical 409813/0815 is formed for each of two axes intersecting at right angles. 4098 13/0816 ι ** Blank page