EP0171487B1 - Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle - Google Patents

Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle Download PDF

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Publication number
EP0171487B1
EP0171487B1 EP19840870120 EP84870120A EP0171487B1 EP 0171487 B1 EP0171487 B1 EP 0171487B1 EP 19840870120 EP19840870120 EP 19840870120 EP 84870120 A EP84870120 A EP 84870120A EP 0171487 B1 EP0171487 B1 EP 0171487B1
Authority
EP
European Patent Office
Prior art keywords
opening
movable plate
section
collecting nozzle
cross
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19840870120
Other languages
English (en)
French (fr)
Other versions
EP0171487A1 (de
Inventor
Jean Bette
Clément Bienvenu
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ROTARY NOZZLE INTERNATIONAL SA
Hepworth Refractories (Belgium) SA
Original Assignee
"rotary Nozzle International Sa"
"societe Belge Des Produits Refractaires En Abrege "belref"
"rotary Nozzle International Sa"
Hepworth Refractories (Belgium) SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
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Publication date
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=8193145&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0171487(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by "rotary Nozzle International Sa", "societe Belge Des Produits Refractaires En Abrege "belref", "rotary Nozzle International Sa", Hepworth Refractories (Belgium) SA filed Critical "rotary Nozzle International Sa"
Priority to EP19840870120 priority Critical patent/EP0171487B1/de
Priority to DE8484870120T priority patent/DE3466861D1/de
Publication of EP0171487A1 publication Critical patent/EP0171487A1/de
Application granted granted Critical
Publication of EP0171487B1 publication Critical patent/EP0171487B1/de
Expired legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D41/00Casting melt-holding vessels, e.g. ladles, tundishes, cups or the like
    • B22D41/14Closures
    • B22D41/22Closures sliding-gate type, i.e. having a fixed plate and a movable plate in sliding contact with each other for selective registry of their openings
    • B22D41/24Closures sliding-gate type, i.e. having a fixed plate and a movable plate in sliding contact with each other for selective registry of their openings characterised by a rectilinearly movable plate

Definitions

  • the subject of the present invention is an external closure device for a container containing molten metal, in particular a ladle for casting steel from a converter or an electric furnace in a continuous casting installation, comprising a fixed plate having at least one opening and made integral with the bottom of the container, a mobile plate provided with at least one opening, means arranged to firmly apply the mobile plate to the face of the fixed plate facing outwards from the container and to slide the face of the movable plate relative to the face of the fixed plate with which it is in contact to bring the opening of the movable plate opposite that of the fixed plate, an internal or upper nozzle fixed to the face of the fixed plate facing the inside of the container and surrounding the opening made in this plate to channel the molten metal towards this opening and a collecting nozzle fixed on the face of the movable plate opposite the fixed plate and surrounding the opening of this movable plate to collect the molten metal escaping through the openings of the fixed and movable plates placed partially or completely opposite one another.
  • the collecting nozzle In known external closure devices, the collecting nozzle, the role of which is to channel the metal jet flowing through the openings of the plates, has an internal conduit which has a practically constant section over its entire length, this section corresponding substantially to that of the opening of the movable plate. It is found in these devices that the throttling of the jet of molten metal, during the gradual matching of the openings of the fixed and mobile plates and especially at the start of casting where this throttling is the most significant, deviates the jet obliquely with respect to vertically and projects it forcefully onto a very localized part of the internal wall of the collecting nozzle which is generally not very thick, which not only has the drawback of causing accelerated wear of this part of the wall of the nozzle and therefore premature wear of the latter, but also the serious disadvantage of running the risk of an accidental breakthrough of the wall of the nozzle at the place where it undergoes the impact of the deflected jet of metal. In addition, these devices also have the disadvantage that the throttling of the metal jet,
  • the object of the invention is to remedy these drawbacks and to provide a closure device whose collector nozzle and especially the fixed and movable plates have a markedly increased longevity compared to that of known devices and which makes it possible to significantly reduce the risk of accidental breakthrough of the wall of the collecting nozzle under the action of the jet of molten metal.
  • the internal duct of the collecting nozzle has two adjacent parts, the first part, which extends from the end of the duct closest to the movable plate, having a section less than that of the opening presented by the movable plate, the second part of said internal conduit having a section greater than the section of the first part of this conduit.
  • the length of the first part of the internal conduit of the collecting nozzle is at most equal to one third of the length of said conduit.
  • the collecting nozzle has, at its end intended to cooperate with the movable plate, an additional thickness forming an external collar, the length of the first part of the internal duct of the collecting nozzle being at least equal to the corresponding dimension of this necklace.
  • the openings presented by the plates are substantially cylindrical, the internal conduit of the internal or upper nozzle being coaxial with the opening of the fixed plate, its section being substantially constant over its whole length and substantially equal to that of said opening, the internal conduit of the collecting nozzle being coaxial with the opening of the movable plate, the first and second parts of the latter conduit being substantially cylindrical.
  • the known closure device shown in Figures 1 to 3, and the closure device according to the invention, shown in Figures 4 to 7, are intended to ensure the external closure of a container 1 containing molten metal and in particular a ladle for casting molten steel from a converter or an electric furnace in a continuous casting installation.
  • These devices each comprise a fixed plate 2, provided with at least one aperture 3, integral with the bottom of the container, a movable plate 4 having at least one opening 5, means, not shown, arranged, on the one 'hand to firmly apply one on the other the faces 6 and 7 of the fixed and movable plate and, on the other hand, to slide the face 7 of the movable plate 4, relative to the face 6 of the fixed plate 2 with which it is in contact, to bring the opening 5 of the movable plate 4 partially or completely opposite the opening 3 of the fixed plate, an internal or upper nozzle 8, fixed to the face 9 of the fixed plate 2, which surrounds the opening 3 of the latter to channel the molten metal towards this opening 3 and a collecting nozzle 10, fixed to the face 11 of the movable plate 4, which surrounds the opening 5 formed in this plate 4, for collecting and channel the molten metal escaping through the openings 3 and 5 placed partially or totally opposite each other.
  • edges 14 of the openings 3 and 5 for throttling the jet wear out very quickly, which leads to the premature replacement of the plates 2 and 4 which are the most more expensive of the closing device.
  • the collecting nozzle 10 is arranged to straighten the jet of molten metal so that it does not strike a very localized area of the thin part of its wall.
  • this nozzle 10 no longer requires a throttling of the jet, at the start of casting, as pushed as in the known closure device, which has the effect of increasing the longevity of the fixed 2 and mobile 4 plates.
  • the internal conduit 15 of the collecting nozzle 10 of the device according to the invention has a first part 16 which extends from its end. mite closest to the movable plate 4 and whose cross section is less than that of the opening 5 of the movable plate, the cross section of the second part 17 of the conduit 15 being greater than that of the first part 16.
  • the cross section of this part 17 of the duct is either less than the section of the opening 5 of the movable plate 4, or equal to this section.
  • the first part 16 of the internal conduit 15 of the collecting nozzle causes the throttling and braking of the jet of molten liquid and therefore contributes to the throttling provided by the partial matching of the openings 3 and 5. Therefore, at the start of casting, for a total pressure drop equivalent to that of the known device, the surfaces of the reconciled openings can be larger and the edges 14 above said more spaced from each other, hence less wear of the fixed plates and mobile, which has a very important advantage in that in addition to their high cost, their replacement is a relatively long and complicated operation.
  • This part 16 of the internal conduit straightens, as shown in FIG. 4, the jet of molten metal shown diagrammatically by the arrow 12, so that this jet either has no more impact on a localized part of the thin wall of the lower part of the nozzle 10, that this impact is greatly reduced.
  • Part 16 is subjected, under the aforementioned service conditions at the start of casting, to relatively high wear, so that the internal section of the duct 15, in this part 16, gradually increases.
  • This characteristic is beneficial as the flow resistance of the molten metal decreases at the same time that the ladle empties and the ferrostatic pressure decreases.
  • the ratios section of part 16 / section of part 17 and section of opening 5 and height h of part 16 / total height H of nozzle 10 will be determined according to the duration of the pouring and the aggressiveness molten metal on the products constituting the plates and nozzle 10 (temperature and composition of the metal).
  • the collecting nozzle 10 has, at its end cooperating with the plate 4, an additional thickness forming an external collar 18.
  • the nozzle 10 which is rarely heated prior to casting the molten metal, is subjected at the start of casting to an extremely brutal thermal shock and the sensitive section of the nozzle to this shock is located at the connection point. of the nozzle and its aforementioned extra thickness. It is therefore beneficial to strengthen the nozzle at this location.
  • the execution according to the invention achieves this reinforcement when the height h. Of the aforementioned part 16 is greater than the height of the collar.
  • the openings 3 and 5 of the plates 2 and 4 are substantially cylindrical
  • the internal conduit of the upper nozzle 8 is coaxial with the opening 3 of the fixed plate and section is substantially constant over its entire length and substantially equal to that of the opening 3
  • the internal conduit 15 of the collecting nozzle 10 is coaxial with the opening 5 of the movable plate 4, the parts 16 and 17 of this conduit 15 being substantially cylindrical.
  • the movable plate 4 has, on its face 11 and on the periphery of the opening 5, an annular projection 19 coaxial with the latter.
  • This projection 19 is intended to cooperate with a corresponding recess 20 produced at the end of the nozzle 10 to be associated with the movable plate 4 and coaxial with the internal conduit 15 of said nozzle.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)

Claims (7)

1. Vorrichtung zum Außenabschluß eines Gefäßes (1), das schmelzflüssiges Metall enthält, insbesondere einer Pfanne für den von einem Konverter oder einem Elektroofen kommenden Stahlguß in einer Stranggießanlage, die eine feste Platte (2) aufweist, die wenigstens eine Öffnung (3) hat und fest mit dem Gefäß verbunden ist, ferner eine bewegliche Platte (4) aufweist, die mit wenigstens einer Öffnung (5) versehen ist, sowie Antriebseinrichtungen zum Schließen der beweglichen Platte (4) auf der Fläche der festen Platte (2) unter Ausführung einer Drehbewegung von dem Gefäß nach außen, welche die Fläche der beweglichen Platte (4) bezüglich einer Fläche der festen Platte (2) gleitbar lagert, mit der sie zur Ausrichtung der Öffnung (5) der beweglichen Platte (4) bezüglich jener der festen Platte in Kontakt ist, einen inneren oder oberen Ausguß (8), der an der Fläche der festen Platte zum Inneren des Gefäßes zugewandt befestigt ist und der die Öffnung (3) umgibt, die in dieser Platte ausgebildet ist, um das schmelzflüssige Metall zur Öffnung zu loiton und einen Sammelausguß (10) aufweist, der an der Fläche der beweglichen Platte (4) befestigt ist, die der festen Platte gegenüberliegt und die die Öffnung (5) dieser beweglichen Platte umgibt, um das durch die Öffnungen (3, 5) der festen und beweglichen Platte, die teilweize oder vollständig zueinander ausgerichtet sind, ausströmende schmelzflüssige Metall zu sammeln, dadurch gekennzeichnet, daß der innere Durchgang (15) des Sammelausgußes (10) zwei benachbarte Abschnitte (16, 17) aufweist, wobei der erste Abschnitt (16), der sich ausgehend von der beweglichen Platte (4) am nächsten liegenden Ende des Durchgangs (15) erstreckt, einen kleineren Querschnitt als die in der beweglichen Platte (4) vorgesehene Öffnung (5) hat, und wobei der zweite Abschnitt (17) des inneren Durchganges (15) einen größeren Querschnitt als der Querschnitt des ersten Abschnittes (16) dieses Durchganges hat.
2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der Querschnitt des zweiten Abschnittes (17) des inneren Durchganges (15) des Sammelausgußes (10) entweder kleiner als der Querschnitt der Öffnung (5) der beweglichen Platte (4) oder gleich dem letztgenannten ist.
3. Vorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Länge des ersten Abschnittes (16) des inneren Durchganges (15) des Sammelausgußes (10) höchstens gleich einem Drittel der Gesamtlänge des Durchganges (15) ist.
4. Vorrichtung nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, daß der Sammelausguß (10) an seinem mit der beweglichen Platte (4) zusammenarbeitenderi Ende ein überdickes Teil aufweist, das einen äußeren Bund (18) bildet, und daß die Länge des ersten Abschnittes (16) des inneren Durchganges (15) des Sammelausgußes größer als die entsprechenden Abmessungen des Bundes (18) ist.
5. Vorrichtung nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Querschnitt der von der beweglichen Platte (4) gebildeten Öffnung (5) kleiner oder gleich dem Querschnitt der von der festen Platte (2) gebildeten Öffnung (3) ist.
6. Vorrichtung nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, daß die von den Platten (2, 4) gebildeten Öffnungen (3, 5) im wesentlichen zylindrisch sind, daß der innere Durchgang des inneren oder oberen Ausgußes (8), der koaxial zur Öffnung (3) der festen Platte (2) ist, einen Querschnitt hat, der im wesentlichen über die gesamte Länge konstant und im wesentlichen gleich jener der Öffnung (3) ist, daß der innere Durchgang (15) des Sammelausgußes (10) koaxial zur Öffnung (5) der beweglichen Platte (4) ist, und daß der erste und der zweite Abschnitt (16, 17) des zuletztgenannten Durchganges etwa zylindrisch sind.
7. Vorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß die bewegliche Platte (4) an ihrer dem Sammelausguß (10) zugewandten Fläche (11) und auf dem Rand um die Öffnung (5) einen Ringvorsprung (19) aufweist, der zur Öffnung koaxial ist, daß der Ringvorsprung mit einer entsprechenden Aussparung (20) zusammenarbeitet, die an einem Ende des Sammelausgußes vorgesehen ist, das zum Zusammenwirken mit der beweglichen Platte bestimmt ist, und daß die Aussparung (20) koaxial zum inneren Durchgang (15) des Sammelausgußes ist.
EP19840870120 1984-08-14 1984-08-14 Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle Expired EP0171487B1 (de)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP19840870120 EP0171487B1 (de) 1984-08-14 1984-08-14 Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle
DE8484870120T DE3466861D1 (en) 1984-08-14 1984-08-14 Device for the external closing of a vessel for molten metal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP19840870120 EP0171487B1 (de) 1984-08-14 1984-08-14 Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle

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EP0171487A1 EP0171487A1 (de) 1986-02-19
EP0171487B1 true EP0171487B1 (de) 1987-10-21

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EP19840870120 Expired EP0171487B1 (de) 1984-08-14 1984-08-14 Vorrichtung zum Aussenabschluss eines Gefässes für schmelzflüssige Metalle

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DE (1) DE3466861D1 (de)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5198126A (en) * 1987-02-28 1993-03-30 Thor Ceramics Limited Tubular refractory product
US5866022A (en) * 1997-03-24 1999-02-02 North American Refractories Company Refractory pour tube with cast plate

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4260081A (en) * 1978-08-07 1981-04-07 Pol Detalle Slide-valve output regulating throttle
DE3029529A1 (de) * 1980-08-04 1982-03-04 Didier-Werke Ag, 6200 Wiesbaden Gleitschieberverschluss mit austauschbaren feuerfesten verschleissteilen

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DE3466861D1 (en) 1987-11-26
EP0171487A1 (de) 1986-02-19

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