EP0293412A1 - Casting funnel for molten metals. - Google Patents

Casting funnel for molten metals.

Info

Publication number
EP0293412A1
EP0293412A1 EP87907410A EP87907410A EP0293412A1 EP 0293412 A1 EP0293412 A1 EP 0293412A1 EP 87907410 A EP87907410 A EP 87907410A EP 87907410 A EP87907410 A EP 87907410A EP 0293412 A1 EP0293412 A1 EP 0293412A1
Authority
EP
European Patent Office
Prior art keywords
pouring
molten metal
funnel
net
pouring funnel
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.)
Granted
Application number
EP87907410A
Other languages
German (de)
French (fr)
Other versions
EP0293412B1 (en
Inventor
Jerry W Brockmeyer
Leonard S Aubrey
James E Dore
Clifford N Soble
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.)
3A Composites International AG
Original Assignee
Alusuisse Holdings AG
Schweizerische Aluminium AG
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.)
Filing date
Publication date
Application filed by Alusuisse Holdings AG, Schweizerische Aluminium AG filed Critical Alusuisse Holdings AG
Priority to AT87907410T priority Critical patent/ATE59989T1/en
Publication of EP0293412A1 publication Critical patent/EP0293412A1/en
Application granted granted Critical
Publication of EP0293412B1 publication Critical patent/EP0293412B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D35/00—Equipment for conveying molten metal into beds or moulds
    • B22D35/04—Equipment for conveying molten metal into beds or moulds into moulds, e.g. base plates, runners
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22C—FOUNDRY MOULDING
    • B22C9/00—Moulds or cores; Moulding processes
    • B22C9/08—Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates
    • B22C9/086—Filters

Definitions

  • the invention relates to a device for casting molten metal, comprising a pouring funnel for molten metal and transfer devices connected to this pouring funnel in order to bring the molten metal from this pouring funnel to a casting station.
  • the device comprises a pouring funnel for molten metal, transfer devices connected to the pouring funnel in order to bring the molten metal from the pouring funnel to the casting station and is characterized in that the pouring funnel has ventilation devices on the connecting parts between the pouring funnel and the transfer device. in order to allow the gas trapped in the system below the pouring funnel to escape.
  • the pouring funnel has a top part open to fill the molten metal and a bottom part open to the transfer device, the bottom part having a smaller cross section than the top part, and the cross section from the top part to the bottom part narrowed.
  • a filter insert for molten metal preferably a ceramic foam filter, as described above, can be arranged in the pouring funnel.
  • the filter insert is preferably used in the region of the base part in such a way that the entire stream of molten metal has to pass the filter and this results in a substantial removal of the solids.
  • a reshaping peripheral seal surrounding the filter can be provided. The filter insert is thus fitted into the pouring funnel in a sealing manner in order to prevent the molten metal from passing through the filter.
  • a plurality of ventilation devices can of course be provided which improve the escape of trapped air.
  • Figure 1 shows a schematic side view of a typical metal casting process.
  • Figure 2 is a graphical representation of the mold fill rate as a function of time.
  • FIGS. 3a, 3b and 3c are side views of pouring funnels according to the present invention.
  • FIGS. 4a and 4b are side views of alternative embodiments of the pouring funnel according to the present invention.
  • FIG. 5 is a top view of a typical pouring funnel according to the present invention with a plurality of ventilation devices.
  • a typical casting operation with molten metal is shown schematically in Figure 1.
  • a supply 10 of molten metal 11 can, for example, be poured in from above, as shown.
  • a floor pouring or a pouring directly from the melting furnace can also be provided.
  • the pouring funnel 12 is filled from the supply 10 of molten metal and serves as a reservoir with molten metal for the transfer device 13, which in turn is connected to the pouring funnel.
  • the transfer device 13 for the molten metal can consist of a sprue or channels 14, which leads to one or more channels 15 and ultimately serves the pouring opening or a plurality of pouring openings (not shown). It goes without saying that the arrangement, size and number of each of these elements will vary from casting to casting.
  • the mold filling rate as a function of time is shown schematically in FIG. 2, which shows the initial time delay (A) due to the metallostatic supernatant, followed by an increase in the mold filling rate until the strong pressure increase in the mold to decrease the mold filling rate ( B) leads.
  • the mold fill rate can then either level (C), continue to fall, stop completely, or increase further if the pressure can escape. As indicated above, this can happen Exacerbate problem of insufficient mold filling rate if there is a constriction in the system or a ceramic foam filter.
  • FIG. 3A shows the pouring funnel 12 with an upper part 12a open at the top, which receives the molten metal and a lower open bottom part 12b with a smaller cross section than the upper part.
  • the pouring funnel 12 narrows from the upper part 12a to the bottom part 12b.
  • a ceramic foam filter 20 is arranged in the region of the base part 12b in the pouring funnel. The filter lies in the flow of the molten metal, so that the entire amount of the molten metal has to pass through the ceramic foam filter for particle removal.
  • the type of ceramic foam filter according to FIG. 3A is described in the aforementioned US Pat. No. 3,962,081.
  • the constriction which the filter embodies can also be another restriction of the melt flow, for example another filter, a sieve or a constriction in the flow cross section.
  • a reshaping edge seal 21 is provided, surrounding the filter 20. The purpose of the seal is to seal the filter against the pouring funnel in order to prevent metal from passing through the outside of the filter and to ensure that all molten metal flows through the filter and to ensure a sealed filter installation to back up.
  • a reshaping seal is particularly advantageous because it causes filter installation problems due to size and size changes thermal expansion between filter and funnel, which results in high mechanical stress on the filter or funnel components or both, is eliminated.
  • a pure oxide fiber such as zirconium oxide or aluminum oxide fiber is best suited, while for example aluminosilicate fibers are particularly suitable for lower temperatures.
  • a beveled filter in the edge area, matching the pouring funnel contour, is preferred for easy installation.
  • the vent 30 according to the invention is provided on the pouring funnel 12.
  • the vent is arranged in the interior of the wall of the pouring funnel and extends through the pouring funnel base 12b in order to establish the connection to the sprue.
  • a vent 30 is provided in the form of one or more continuous pipe sections, attached to or integrated in the surface on the inside of the pouring funnel 12.
  • 3C shows a vent 30, formed by one or more continuous pipe sections, attached to or integrated into the surface, on the outside of the pouring funnel 12, in order to be connected to the sprue.
  • the embodiment according to Figure 3B uses a ceramic filter 20a made of an extruded ceramic material, while according to Figure 3C a ceramic foam filter 20 is used, as also in Figure 3A. In both cases, a sealing material 21 is applied laterally on the edge of the filter body.
  • FIGS. 4A and 4B show improved pouring funnels 16, comprising an open top part 16a and an open bottom part 16b, in which the bottom part has a smaller diameter than the top part.
  • the open bottom part 16b holds an inward seam 17, which is provided as a supporting or supporting surface for the filter 20a of the type made of extruded ceramic material.
  • FIG. 4A comprises a pouring funnel with an essentially perpendicular bottom part 18 for the simple arrangement of an essentially rectangular filter, while FIG. 4B shows a pouring funnel with an obliquely continuous wall, as shown in FIG. 3.
  • Figure 5 is a top view of a pouring funnel 12 with 4 outer notches 30 as ventilation devices.
  • the exact number of venting devices will vary according to the demands on the pouring funnel.
  • the notches can be filled with wax, which later melts away after the mold has been formed. Without notches, a precision casting vent can be formed by attaching wax to the funnel surface before the mold is formed. In some cases it may be desirable to control the flow in a ventilation system. In this case, a limiting opening or comparable control devices can be inserted into the system.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Molds, Cores, And Manufacturing Methods Thereof (AREA)
  • Laminated Bodies (AREA)
  • Treatment Of Steel In Its Molten State (AREA)

Abstract

A molten metal pouring cup is provided communicating with a transfer means for transferring molten metal from the pouring cup to a casting station. Vent means is provided on the pouring cup at the interface between the pouring cup and the transfer means to permit release of entrapped gas downstream of the pouring cup.

Description

Giesstrichter für geschmolzene Metalle Casting funnel for molten metals
Die Erfindung betrifft eine Vorrichtung zum Gi.essen von ge¬ schmolzenem Metall, umfassend einen Giesstrichter für ge¬ schmolzenes Metall und Transfervorrichtungen, verbunden mit diesem Giesstrichter, um das geschmolzene Metall von diesem Giesstrichter zu einer Giessstation zu bringen.The invention relates to a device for casting molten metal, comprising a pouring funnel for molten metal and transfer devices connected to this pouring funnel in order to bring the molten metal from this pouring funnel to a casting station.
Bei der Anwendung eines Giesstrichters, um geschmolzenes Metall für einen Präzisionsguss, Sandguss oder auch bei anderen Giessverfahren, speziell durch die Gegenwart von Luft in nicht entlüfteten Giessanwendungen, können sich Probleme durch den Druckaufbau in der Giessform ergeben, insbesondere dann, wenn die Luft in der Giessform durch das einfliessende Metall eingeschlossen wird. Der Giessform- hohlraum hat eine beschränkte Kapazität und der Luft in der Giessform ist es nicht möglich, während des Giessens völlig zu entweichen.When using a pouring funnel to melt molten metal for precision casting, sand casting or other casting processes, especially due to the presence of air in non-vented casting applications, problems can arise due to the pressure build-up in the mold, especially if the air in the Mold is enclosed by the incoming metal. The mold cavity has a limited capacity and it is not possible for the air in the mold to escape completely during the casting.
Wenn es das System verunmöglicht, die in der Giessform ein¬ geschlossene Luft während des Giessens entweichen zu las¬ sen, führt der Druckaufbau im System zu einer Verkleinerung der Füllrate beim Füllen des Giessformhohlraumes. In den ungünstigsten Fällen wird beim Guss die Hohlform nicht vollständig gefüllt und es resultiert eine Fehlfüllung und Ausschussmaterial. In leichteren Fällen wird die Füllzeit verzögert, was auch zu Giessdefekten führen kann, wie Fal- ten, schlechte Füllung in Zonen mit feinen Details oder zu dünnen Abschnitten. Dies stellt ein Problem dar, das eine teure Nacharbeitung verursachen oder sogar zu einer totalen Unbrauchbarkeit des Stückes führen kann. Die schon redu¬ zierte Fliessrate bei einem derartigen Druckaufbau ver- schlechtert sich noch mehr, wenn eine Einengung oder ein begrenztes Fliessgebiet, wie ein Filter, im System vorhan¬ den ist, die beide die Bildung eines metallostatischen Ueberstandes und einen sich nicht entlüftenden Giesszustand verursachen. Filter oben genannter Art für geschmolzene Me¬ talle, wie beispielsweise der bekannte keramische Schaum¬ filter, beschrieben in der US-PS 3 962 081, bieten markante Fortschritte im Entfernen von Festkörpern aus geschmolzenem Metall, so dass eine Eliminierung des Filters aus dem Sy¬ stem keine befriedigende Lösung des anstehenden Problems darstellen kann.If the system makes it impossible for the air enclosed in the casting mold to escape during casting, the pressure build-up in the system leads to a reduction in the filling rate when filling the casting mold cavity. In the worst cases, the hollow mold is not completely filled during casting, resulting in incorrect filling and rejects. In lighter cases, the filling time is delayed, which can also lead to casting defects, such as folds, poor filling in zones with fine details or too thin sections. This is a problem that can cause expensive rework or even total uselessness of the piece. The already reduced flow rate with such a pressure build-up deteriorates even more if there is a constriction or a limited flow area, such as a filter, in the system, both of which form a metallostatic supernatant and a non-venting pouring state cause. Filters of the above type for molten metals, such as the well-known ceramic foam filter described in US Pat. No. 3,962,081, offer marked advances in the removal of solids from molten metal, so that the filter is eliminated from the system stem cannot provide a satisfactory solution to the problem at hand.
Es ist deshalb ein Hauptgegenstand vorliegender Erfindung, eine Vorrichtung zur Verfügung zu stellen, die es er δg- licht, geschmolzenes Metall zu filtrieren und das Problem des Druckaufbaues in der Giessform durch Luft, die vom ein- fliessenden Metall eingeschlossen wird, eliminert. Es ist ein weiterer Gegenstand vorliegender Erfindung, eine Vor¬ richtung zur Verfügung zu stellen, die wirkungsvoll arbei- tet, wenn eine Verengung des Fliessweges im System vorhan¬ den ist. Ein weiterer Gegenstand vorliegender Erfindung ist es, eine Vorrichtung wie zuvor zur Verfügung zu stellen, die einfach, praktisch und rationell im kommerziellen Rah¬ men angewendet werden kann.It is therefore a main object of the present invention to provide a device which enables the molten metal to be filtered and the problem of pressure build-up in the mold to be eliminated by air enclosed by the inflowing metal. It is a further object of the present invention to provide a device which works effectively when the flow path in the system is narrowed. Another object of the present invention is to provide a device as before, which can be used simply, practically and efficiently in a commercial context.
Die Vorrichtung umfasst einen Giesstrichter für geschmol¬ zenes Metall, Transfervorrichtungen verbunden mit dem Giesstrichter, um das geschmolzene Metall vom Giesstrichter zur Giessstation zu bringen und ist gekennzeichnet, dass der Giesstrichter Entlüftungsvorrichtungen an der Verbin- dungssteile zwischen dem Giesstrichter und der Transfervor¬ richtung aufweist, um dem im System unterhalb des Giess- trichters eingeschlossenen Gas das Entweichen zu ermögli¬ chen.The device comprises a pouring funnel for molten metal, transfer devices connected to the pouring funnel in order to bring the molten metal from the pouring funnel to the casting station and is characterized in that the pouring funnel has ventilation devices on the connecting parts between the pouring funnel and the transfer device. in order to allow the gas trapped in the system below the pouring funnel to escape.
Es wurde gefunden, dass dadurch das Problem des Druckauf- baues, verursacht durch die im System eingeschlossenen Ga¬ se, in der Regel Luft, eliminiert wird. Durch die erfin- dungsgemässe einfache Ausführungsform der Ξntlüftungsvor- richtung am Giesstrichter ist deren Anwendung besonders einfach und dient auch dazu, die mit einer Verengung im Sy- stem auftretenden Probleme zu eliminieren.It was found that this eliminates the problem of pressure build-up, caused by the gases enclosed in the system, usually air. Due to the simple embodiment of the ventilation device on the pouring funnel according to the invention, its use is particularly simple and also serves to reduce the to eliminate problems that arise.
Vorzugsweise hat der Giesstrichter einen nach oben offenen Oberteil, um das geschmolzene Metall einzufüllen und einen nach unten offenen Bodenteil, der mit der Transfervorrich- tung verbunden ist, wobei der Bodenteil einen kleineren Querschnitt hat als der Oberteil, und sich der Querschnitt vom Oberteil zum Bodenteil verengt. Ein Filtriereinsatz für geschmolzenes Metall, bevorzugt ein keramischer Schaumfil¬ ter, wie oben beschrieben, kann im Giesstrichter angeordnet werden. Bevorzugt wird der Filtriereinsatz derart im Be¬ reich des Bodenteils eingesetzt, dass der ganze Strom an geschmolzenem Metall den Filter passieren muss und daraus eine weitgehende Entfernung der Feststoffe resultiert. Es kann eine rückformende periphere Dichtung, die den Filter randständig umgibt, vorgesehen werden. Der Filtriereinsatz ist somit dichtend gegenüber dem Giesstrichter in diesen eingepasst, um so einen Durchtritt des geschmolzenen Me¬ talles am Filter vorbei zu vermeiden. Im Rahmen vorliegen¬ der Erfindung können selbstverständlich eine Mehrzahl von Entlüftungsvorrichtungen vorgesehen werden, die das Entwei¬ chen von eingeschlossener Luft verbessern.Preferably, the pouring funnel has a top part open to fill the molten metal and a bottom part open to the transfer device, the bottom part having a smaller cross section than the top part, and the cross section from the top part to the bottom part narrowed. A filter insert for molten metal, preferably a ceramic foam filter, as described above, can be arranged in the pouring funnel. The filter insert is preferably used in the region of the base part in such a way that the entire stream of molten metal has to pass the filter and this results in a substantial removal of the solids. A reshaping peripheral seal surrounding the filter can be provided. The filter insert is thus fitted into the pouring funnel in a sealing manner in order to prevent the molten metal from passing through the filter. Within the scope of the present invention, a plurality of ventilation devices can of course be provided which improve the escape of trapped air.
Anhand vorliegender Abbildungen ist die Erfindung näher er¬ läutert.The invention is explained in more detail with the aid of the present figures.
Abbildung 1 stellt eine schematische Seitenansicht eines typischen Metallgussverfahrens dar.Figure 1 shows a schematic side view of a typical metal casting process.
Abbildung 2 ist die graphische Darstellung der Giessform- einfüllrate in Funktion- der Zeit.Figure 2 is a graphical representation of the mold fill rate as a function of time.
Figuren 3a, 3b und 3c sind Seitenansichten von Giesstrich- tern nach vorliegender Erfindung. Figuren 4a und 4b sind Seitenansichten von alternativen Ausführungsformen der Giesstrichter nach vorliegender Er¬ findung.Figures 3a, 3b and 3c are side views of pouring funnels according to the present invention. FIGS. 4a and 4b are side views of alternative embodiments of the pouring funnel according to the present invention.
Figur 5 ist die Draufsicht auf einen typischen Giesstrich- ter nach vorliegender Erfindung mit einer Mehrzahl von Ent¬ lüftungsvorrichtungen.FIG. 5 is a top view of a typical pouring funnel according to the present invention with a plurality of ventilation devices.
Eine typische Giessoperation mit geschmolzenem Metall wird schematisch in Figur 1 gezeigt. Ein Vorrat 10 an geschmol¬ zenem Metall 11 kann beispielsweise, wie gezeigt, von oben eingegossen werden. Es kann auch ein Bodeneinguss oder ein Einguss direkt vom Schmelzofen vorgesehen werden. Aus dem Vorrat 10 an geschmolzenem Metall wird der Giesstrichter 12 befüllt und dient als Reservoir mit geschmolzenem Metall für die Transfervorrichtung 13, die ihrerseits mit dem Giesstrichter verbunden ist. Die Transfervorrichtung 13 für das geschmolzene Metall kann aus einem Eingusskanal oder - Kanälen 14 bestehen, der zu einer oder mehreren Rinnen 15 führt und letztendlich die Giessöffnung oder eine Mehrzahl von Giessδffnungen (nicht gezeigt) bedient. Selbstverständ- lieh wird die Anordnung, Grosse und Zahl jedes dieser Ele¬ mente von Guss zu Guss unterschiedlich sein.A typical casting operation with molten metal is shown schematically in Figure 1. A supply 10 of molten metal 11 can, for example, be poured in from above, as shown. A floor pouring or a pouring directly from the melting furnace can also be provided. The pouring funnel 12 is filled from the supply 10 of molten metal and serves as a reservoir with molten metal for the transfer device 13, which in turn is connected to the pouring funnel. The transfer device 13 for the molten metal can consist of a sprue or channels 14, which leads to one or more channels 15 and ultimately serves the pouring opening or a plurality of pouring openings (not shown). It goes without saying that the arrangement, size and number of each of these elements will vary from casting to casting.
Es ist .leicht erkennbar, dass das beschriebene System beim Entweichen der in der Giessform eingeschlossenen Luft ver¬ sagen kann, wobei ein Druckanstieg im System erfolgt und die eingangs beschriebenen Probleme verursacht werden. Die Giessformfüllrate als eine Funktion der Zeit ist schema¬ tisch in Figur 2 gezeigt, welche die anfängliche Zeitver¬ zögerung (A) durch den metallostatischen Ueberstand zeigt, gefolgt von einem Anstieg in der Giessformfüllrate bis der starke Druckanstieg in der Giessform zum Absinken der Giessformfüllrate (B) führt. Die Giessformf llrate kann dann entweder nivellieren (C), weiter fallen, vollständig aufhören, oder aber kann weiter ansteigen, wenn der Druck entweichen kann. Wie weiter oben angedeutet, kann sich das Problem der ungenügenden Giessformfüllrate verschärfen, wenn eine Verengung im System oder ein keramischer Schaum¬ filter vorhanden ist.It is easy to see that the system described can fail to escape the air enclosed in the casting mold, causing an increase in pressure in the system and causing the problems described at the beginning. The mold filling rate as a function of time is shown schematically in FIG. 2, which shows the initial time delay (A) due to the metallostatic supernatant, followed by an increase in the mold filling rate until the strong pressure increase in the mold to decrease the mold filling rate ( B) leads. The mold fill rate can then either level (C), continue to fall, stop completely, or increase further if the pressure can escape. As indicated above, this can happen Exacerbate problem of insufficient mold filling rate if there is a constriction in the system or a ceramic foam filter.
Wie obenstehend angegeben, wurde gefunden, dass dieses Problem durch die erfindungsgemässen Vorkehrungen von Ent¬ lüftungsvorrichtungen am Giesstrichter im Berührungspunkt zwischen dem Giesstrichter und der Transfervorrichtung für das geschmolzene Metall, die das Entweichen von einge¬ schlossenem Gas stromabwärts vom Giesstrichter erlauben, eliminiert werden kann. Figuren 3 bis 5 zeigen typische Ausführungsformen vorliegender Erfindung.As stated above, it was found that this problem can be eliminated by the inventive arrangements of ventilation devices on the pouring funnel at the point of contact between the pouring funnel and the transfer device for the molten metal, which allow the enclosed gas to escape downstream of the pouring funnel. Figures 3 to 5 show typical embodiments of the present invention.
Fig. 3A zeigt den Giesstrichter 12 mit einem oben offenen Oberteil 12a, der das geschmolzene Metall aufnimmt und ein¬ en unteren offenen Bodenteil 12b mit einem kleineren Quer- schnitt als ihn der Oberteil aufweist. Wie in Figur 3a ge¬ sehen werden kann, verengt sich der Giesstrichter 12 vom Oberteil 12a zum Bodenteil 12b. Ein keramischer Schaumfil¬ ter 20 ist im Bereich des Bodenteils 12b im Giesstrichter angeordnet. Der Filter liegt im Fluss des geschmolzenen Me- talles, so dass die ganze Menge des geschmolzenen Metalles den keramischen Schaumfilter zur Partikelentfernung pas¬ sieren muss. Der keramische Schaumfilter nach Fig. 3A wird in seiner Art in der schon erwähnten US-PS 3.962 081 be¬ schrieben. Die Verengung, welche der Filter verkörpert, kann auch eine andere Einschränkung des Schmelzflusses sein, z.B. ein anderer Filter, ein Sieb oder eine Verengung im Fliessquerschnitt. Eine rückformende randständige Dich¬ tung 21 ist, den Filter 20 umgebend, vorgesehen. Die Dich¬ tung hat den Zweck, den Filter gegen den Giesstrichter hin abzudichten, um ein Durchtreten von Metall, aussen am Fil¬ ter vorbei, zu vermeiden und um sicher zu stellen, dass alles geschmolzene Metall den Filter durchströmt und um einen dichtenden Filtereinbau zu sichern. Eine rückformende Dichtung ist besonders vorteilhaft, da sie Filtereinbau- probleme aufgrund von Grosse- und Massveränderungen durch thermische Expansion zwischen Filter und Trichter, die in hoher mechanischer Beanspruchung auf die Filter- oder Trichterbauteile oder beides resultiert, eliminiert. Selbstverständlich hängt die Wahl der speziellen Dichtung von der Anwendung ab, z.B. für Hochtemperaturanwendungen, wie die Stahlfiltration, ist eine reine Oxidfaser wie Zir- konoxid- oder Aluminiumoxidfaser am besten geeignet, wäh¬ rend beispielsweise Aluminosilikatfasern für tiefere Tem¬ peraturen besonders geeignet sind. Ebenso, wie gezeigt in Fig. 3A,- wird ein im Randbereich abgeschrägter Filter, passend zur Giesstrichterkontur, für einen leichten Einbau bevorzugt.3A shows the pouring funnel 12 with an upper part 12a open at the top, which receives the molten metal and a lower open bottom part 12b with a smaller cross section than the upper part. As can be seen in FIG. 3a, the pouring funnel 12 narrows from the upper part 12a to the bottom part 12b. A ceramic foam filter 20 is arranged in the region of the base part 12b in the pouring funnel. The filter lies in the flow of the molten metal, so that the entire amount of the molten metal has to pass through the ceramic foam filter for particle removal. The type of ceramic foam filter according to FIG. 3A is described in the aforementioned US Pat. No. 3,962,081. The constriction which the filter embodies can also be another restriction of the melt flow, for example another filter, a sieve or a constriction in the flow cross section. A reshaping edge seal 21 is provided, surrounding the filter 20. The purpose of the seal is to seal the filter against the pouring funnel in order to prevent metal from passing through the outside of the filter and to ensure that all molten metal flows through the filter and to ensure a sealed filter installation to back up. A reshaping seal is particularly advantageous because it causes filter installation problems due to size and size changes thermal expansion between filter and funnel, which results in high mechanical stress on the filter or funnel components or both, is eliminated. Of course, the choice of the special seal depends on the application, for example for high temperature applications such as steel filtration, a pure oxide fiber such as zirconium oxide or aluminum oxide fiber is best suited, while for example aluminosilicate fibers are particularly suitable for lower temperatures. Likewise, as shown in Fig. 3A, - a beveled filter in the edge area, matching the pouring funnel contour, is preferred for easy installation.
Die erfindungsgemässe Entlüftung 30 ist am Giesstrichter 12 vorgesehen. In der Ausführungsform nach Abbildung 3A ist die Entlüftung im Innern der Wand des Giesstrichters ange¬ ordnet und erstreckt sich durch den Giesstrichterboden 12b, um die Verbindung mit dem Eingusskanal herzustellen. In der Ausführungsform von Abbildung 3B ist eine Entlüftung 30 in Form einer oder mehrerer durchgängiger Rohrabschnitte, befestigt an, oder integriert in der Oberfläche innen am Giesstrichter 12, vorgesehen. Abbildung 3C zeigt eine Ent¬ lüftung 30, gebildet durch eine oder mehrere durchgängiger Rohrabschnitte, befestigt an oder integriert in die Ober¬ fläche, aussen am Giesstrichter 12, um mit dem Eingusskanal in Verbindung zu stehen. Die Ausfuhrungsform nach Abbildung 3B verwendet einen keramischen Filter 20a aus einem extru- dierten keramischen Material, während nach Abbildung 3C ein keramischer Schaumfilter 20 verwendet wird, wie auch in Ab¬ bildung 3A. In beiden Fällen wird seitlich am Rande des Filterkörpers ein Dichtungsmaterial 21 angewendet.The vent 30 according to the invention is provided on the pouring funnel 12. In the embodiment according to FIG. 3A, the vent is arranged in the interior of the wall of the pouring funnel and extends through the pouring funnel base 12b in order to establish the connection to the sprue. In the embodiment of Figure 3B, a vent 30 is provided in the form of one or more continuous pipe sections, attached to or integrated in the surface on the inside of the pouring funnel 12. 3C shows a vent 30, formed by one or more continuous pipe sections, attached to or integrated into the surface, on the outside of the pouring funnel 12, in order to be connected to the sprue. The embodiment according to Figure 3B uses a ceramic filter 20a made of an extruded ceramic material, while according to Figure 3C a ceramic foam filter 20 is used, as also in Figure 3A. In both cases, a sealing material 21 is applied laterally on the edge of the filter body.
Abbildungen 4A und 4B zeigen verbesserte Giesstrichter 16, umfassend einen offenen Oberteil 16a und einen offenen Bo¬ denteil 16b, worin der Bodenteil einen kleineren Durchmes¬ ser aufweist als der Oberteil. Der offene Bodenteil 16b um- fasst einen einwärts gerichteten Saum 17, der als abstüt¬ zende oder tragende Fläche für den Filter 20a des Types aus extrudiertem keramischen Material vorgesehen ist. Abbildung 4A umfasst einen Giesstrichter mit einem im wesentlichen senkrecht ausgebildeten Bodenteil 18 für die einfache An¬ ordnung eines im wesentlichen rechteckigen Filters, während Abbildung 4B einen Giesstrichter mit schräg fortlaufender Wandung, wie die Abbildungen 3 zeigen.FIGS. 4A and 4B show improved pouring funnels 16, comprising an open top part 16a and an open bottom part 16b, in which the bottom part has a smaller diameter than the top part. The open bottom part 16b holds an inward seam 17, which is provided as a supporting or supporting surface for the filter 20a of the type made of extruded ceramic material. FIG. 4A comprises a pouring funnel with an essentially perpendicular bottom part 18 for the simple arrangement of an essentially rectangular filter, while FIG. 4B shows a pouring funnel with an obliquely continuous wall, as shown in FIG. 3.
Abbildung 5 ist die Draufsicht auf einen Giesstrichter 12 mit 4 äusseren Einkerbungen 30 als Entlüftungsvorrich- tungen. Selbstverständlich wird die exakte Zahl von Entlüf¬ tungsvorrichtungen entsprechend den Ansprüchen an den Giesstrichter variieren. Für Präzisionsguss können die Ein¬ kerbungen mit Wachs gefüllt sein, der .später nach der Aus- bildung der Form wegschmilzt. Ohne Einkerbungen kann eine Entlüftungsvorrichtung für Präzisionsguss durch Befestigen von Wachs an der Trichteroberfläche, bevor die Form geformt wird, gebildet werden. In einigen Fällen kann es wünschens¬ wert sein, die Strömung in einem Entlüftungssystem zu kon- trollieren. In diesem Fall kann eine begrenzende Oeffnung oder vergleichbare Kontrollvorrichtungen in das System ein¬ gefügt werden. Figure 5 is a top view of a pouring funnel 12 with 4 outer notches 30 as ventilation devices. Of course, the exact number of venting devices will vary according to the demands on the pouring funnel. For precision casting, the notches can be filled with wax, which later melts away after the mold has been formed. Without notches, a precision casting vent can be formed by attaching wax to the funnel surface before the mold is formed. In some cases it may be desirable to control the flow in a ventilation system. In this case, a limiting opening or comparable control devices can be inserted into the system.

Claims

Ansprüche Expectations
1. Vorrichtung zum Giessen von geschmolzenem Metall, um¬ fassend einen Giesstrichter für geschmolzenes Metall und Transfervorrichtungen, verbunden mit diesem Giess- trichter, um das geschmolzene Metall von diesem Giess¬ trichter zu einer Giessstation zu bringen,1. Device for casting molten metal, comprising a pouring hopper for molten metal and transfer devices connected to this pouring hopper to bring the molten metal from this pouring hopper to a casting station.
dadurch gekennzeichnet, dasscharacterized in that
der Giesstrichter wenigstens eine Entlüftungsvorrich¬ tung an der Verbindungsstelle zwischen dem Giesstrich- ter und der Transfervorrichtung aufweist, die ein Ent¬ weichen der unterhalb des Giesstrichters im System ein¬ geschlossenen Luft erlaubt.the pouring funnel has at least one venting device at the connection point between the pouring funnel and the transfer device, which allows the air enclosed in the system below the pouring funnel to escape.
2. Vorrichtung nach Anspruch 1, dadurch gekennzeichnet, dass die Transfervorrichtungen wenigstens einen Ein- gusskanal und wenigstens eine Abstichrinne umfassen.2. Device according to claim 1, characterized in that the transfer devices comprise at least one sprue and at least one tapping channel.
3. Vorrichtung nach Anspruch 1 und 2, dadurch gekennzeich¬ net, dass der Giesstrichter einen nach oben offenen Oberteil, um das geschmolzene Metall aufzunehmen und einen unten offenen Bodenteil, verbunden mit den Trans- fervorrichtungen, aufweist,- wobei der nach unten offene Bodenteil einen kleineren Querschnitt hat als der of¬ fene Oberteil.3. Apparatus according to claim 1 and 2, characterized gekennzeich¬ net that the pouring funnel has an upper part open to receive the molten metal and a lower part open bottom, connected to the transfer devices, - the bottom part open to the bottom has a smaller cross section than the open top part.
4. Vorrichtung nach Anspruch 1 bis 3, dadurch gekennzeich¬ net, dass der Giesstrichter vom nach oben offenen Ober- teil sich gegen den unten offenen Bodenteil verjüngt.4. Apparatus according to claim 1 to 3, characterized gekennzeich¬ net that the pouring funnel tapers from the top part open towards the bottom part open bottom.
5. Vorrichtung nach Anspruch 1 bis 4, dadurch gekennzeich¬ net, dass der Giesstrichter eine Filtriervorrichtung enthält, die im Bereich des offenen Bodenteiles derart angeordnet ist, dass das gesamte geschmolzene Metall diese Filtervorrichtung passieren muss. 5. The device according to claim 1 to 4, characterized gekennzeich¬ net that the pouring funnel contains a filtering device which is arranged in the region of the open bottom part such that the entire molten metal must pass through this filter device.
6. Vorrichtung nach Anspruch 1 bis 5, dadurch gekennzeich¬ net, dass die Filtriervorrichtung gegen den Giesstrich¬ ter mittels einer peripheren rückformenden Dichtung ausgestattet ist, welche die Filtriervorrichtung gegen den Giesstrichter abdichtet, um einen Metalldurchtritt am Filter vorbei zu vermeiden.6. The device according to claim 1 to 5, characterized gekennzeich¬ net that the filtering device against the Giesstrich¬ ter is equipped by means of a peripheral reforming seal, which seals the filtering device against the pouring funnel in order to avoid metal passage past the filter.
7. Vorrichtung nach Anspruch 1 bis 6, dadurch gekennzeich¬ net, dass die Entlüftungsvorrichtung in der Giesstrich- terwand angeordnet ist.7. The device according to claim 1 to 6, characterized gekennzeich¬ net that the venting device is arranged in the pouring spout wall.
8. Vorrichtung nach Anspruch 1 bis 6, dadurch gekennzeich¬ net, dass die Entlüftungsvorrichtung innen am Giess¬ trichter angeordnet ist.8. The device according to claim 1 to 6, characterized gekennzeich¬ net that the venting device is arranged inside the Giess¬ funnel.
9. Vorrichtung nach Anspruch 1 bis 6, dadurch gekennzeich¬ net, dass die Entlüftungsvorrichtung aussen am Giess- trichter angeordnet ist.9. The device according to claim 1 to 6, characterized gekennzeich¬ net that the ventilation device is arranged on the outside of the pouring funnel.
10. Vorrichtung nach Anspruch 1 bis 9, dadurch gekennzeich¬ net, dass sie eine Mehrzahl von diesen Entlüftungsvor¬ richtungen umfasst.10. The device according to claim 1 to 9, characterized gekennzeich¬ net that it comprises a plurality of these venting devices.
11. Vorrichtung nach Anspruch 1 bis 10, dadurch gekenn- zeichnet, dass der Offene Bodenteil einen einwärts ra¬ genden Saum, der den Filter für geschmolzenes Metall aufnimmt, umfasst.11. The device according to claim 1 to 10, characterized in that the open bottom part comprises an inwardly projecting hem which receives the filter for molten metal.
12. Vorrichtung nach Anspruch 1 bis 11, dadurch gekenn¬ zeichnet, dass der offene Bodenteil einen im wesentli- chen rechteckigen Teilquerschnitt zur Filteraufnahme umfasst.12. The device according to claim 1 to 11, characterized gekenn¬ characterized in that the open bottom part comprises a substantially rectangular partial cross-section for filter holder.
13. Vorrichtung nach Anspruch 1 bis 12, dadurch gekenn¬ zeichnet, dass die Entlüf ungsvorrichtung innere Giess- trichterröhren umfasst. 13. The apparatus of claim 1 to 12, characterized gekenn¬ characterized in that the venting device comprises inner pouring funnel tubes.
EP87907410A 1986-12-15 1987-11-26 Casting funnel for molten metals Expired - Lifetime EP0293412B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT87907410T ATE59989T1 (en) 1986-12-15 1987-11-26 PUNCH FOR MOLTEN METALS.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US06/941,809 US4708326A (en) 1986-12-15 1986-12-15 Vented pouring cup for molten metal casting
US941809 1986-12-15

Publications (2)

Publication Number Publication Date
EP0293412A1 true EP0293412A1 (en) 1988-12-07
EP0293412B1 EP0293412B1 (en) 1991-01-16

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Family Applications (1)

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EP87907410A Expired - Lifetime EP0293412B1 (en) 1986-12-15 1987-11-26 Casting funnel for molten metals

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US (1) US4708326A (en)
EP (1) EP0293412B1 (en)
JP (1) JPH01501457A (en)
CN (1) CN87107434A (en)
AT (1) ATE59989T1 (en)
AU (1) AU600053B2 (en)
DE (1) DE3767485D1 (en)
DK (1) DK448488D0 (en)
ES (1) ES2005728A6 (en)
NO (1) NO883628L (en)
WO (1) WO1988004587A1 (en)

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Also Published As

Publication number Publication date
JPH0356145B2 (en) 1991-08-27
ES2005728A6 (en) 1989-03-16
AU8233287A (en) 1988-07-15
EP0293412B1 (en) 1991-01-16
WO1988004587A1 (en) 1988-06-30
JPH01501457A (en) 1989-05-25
CN87107434A (en) 1988-06-29
AU600053B2 (en) 1990-08-02
US4708326A (en) 1987-11-24
NO883628D0 (en) 1988-08-15
DK448488A (en) 1988-08-10
ATE59989T1 (en) 1991-02-15
NO883628L (en) 1988-08-15
DE3767485D1 (en) 1991-02-21
DK448488D0 (en) 1988-08-10

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