EP1213070B1 - Process and device for metalcasting - Google Patents

Process and device for metalcasting Download PDF

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Publication number
EP1213070B1
EP1213070B1 EP01126259A EP01126259A EP1213070B1 EP 1213070 B1 EP1213070 B1 EP 1213070B1 EP 01126259 A EP01126259 A EP 01126259A EP 01126259 A EP01126259 A EP 01126259A EP 1213070 B1 EP1213070 B1 EP 1213070B1
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EP
European Patent Office
Prior art keywords
filling
level
metal
melting furnace
mould
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EP01126259A
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German (de)
French (fr)
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EP1213070A3 (en
EP1213070A2 (en
Inventor
Johann Wolf
Franz-Josef Bachhuber
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Bayerische Motoren Werke AG
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Bayerische Motoren Werke AG
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D18/00Pressure casting; Vacuum casting
    • B22D18/08Controlling, supervising, e.g. for safety reasons
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D18/00Pressure casting; Vacuum casting
    • B22D18/04Low pressure casting, i.e. making use of pressures up to a few bars to fill the mould

Definitions

  • the invention relates to a metal casting method and a metal casting device, especially according to the low pressure casting principle for series production of aluminum castings, according to the preamble of claim 1 or 6.
  • the melting furnace must be in front of everyone Mold filling process, but also depressurized for refilling the weld pool and the actual casting process is interrupted during this time, which increased downtime and a corresponding decrease in average Production rate.
  • the main problem is that due to the refilling process, there is an increased gas absorption and formation of oxide skin in the melt and highly undesirable corundum deposits in the oven and thereby a loss of quality to the Castings that come in terms of strict quality requirements, such as they are placed on aluminum castings in the automotive industry, cannot be accepted.
  • the object of the invention is the method and the device of the beginning the type mentioned so that the mentioned, refill-related impurities of the weld pool can be significantly reduced.
  • this object is characterized by that in claim 1 Method or the casting device characterized in claim 6 solved.
  • the metal level in the filling tube is for the duration of the refilling process regardless of the degree of filling of the furnace at or above the level the end of the riser pipe, i.e. clearly above the metal level in the Melting furnace, and thus the free fall height of the melt at Refilling significantly reduced, with the result that oxide skin formation and gas absorption of the molten metal due to the largely swirl-free Melt entry as well as by spraying metal particles caused corundum formation are effectively suppressed and thereby ensured is that the weld pool in the furnace and consequently also the Metal filling of the mold of disruptive contaminants, such as gas, oxide skin or corundum inclusions, kept free and the casting quality significant is improved.
  • the metal mirror in Filling tube according to claim 2 with regard to a simple level control during the refill phase through a gas pressure control that is dependent on the fill level signal of the filling tube furnace system to the specified level.
  • the metal melt during the mold filling process under low pressure from the melting furnace into one with the riser selectively coupled mold so the filling tube is particularly preferably kept constantly under ambient pressure and the gas pressure in the melting furnace between the mold filling phases continuously on one Metal mirror in the filler pipe at the level of the riser outlet area on the mold side maintaining overpressure value adjusted.
  • the level measurement in the filling tube according to claim 4 preferably also Monitoring and control of the melt rise in the mold up to Reaching the upper mold filling limit and thus the otherwise to this Purpose required, separate level measurement directly on the casting mold made unnecessary.
  • the gas pressure above the metal level in the fill pipe is dependent on a fill level signal operated, on the one hand with the ambient pressure and on the other hand controlled with the furnace pressure 3-way valve so that the filling level in the filling pipe is only for the duration of the refilling phase Height of the riser outlet area brought, but otherwise to the metal bath level the furnace is lowered.
  • This variant also has the thermal advantage that by lowering the molten metal in the filling pipe between the refill phases is easily prevented that the liquid metal in the The filling pipe cools down too much and then precipitates on the inside of the filling pipe.
  • the casting plant shown in Fig. 1 is used for the production of aluminum castings according to the low pressure process and contains a melting furnace 2 with an immersion in the melt pool 4, which protrudes beyond the furnace top Riser pipe 6 for filling one selectively with the upper, funnel-shaped extended riser pipe end coupling mold 8 as well as with a likewise in the metal bath 4 immersed filling tube 10, which at the top, on the Filling upper limit A of the mold 8 protruding end through a cover 12 is closed with a refill and vent opening 14.
  • the gas pressure inside the furnace is identified with the help of a total of 16 Regulated gas pressure control, which from a pressure gas container 18, a reversible between this and a vent and a closed position Multi-way valve 20, a control unit 22 for valve actuation and a measuring the height level of the liquid metal column in the filling tube 10, Level sensor 24 connected on the output side to control unit 22 there, the level in the riser 6 and in the mold 8 after the principle of communicating tubes at the same height as in the filling tube 10 lies and is therefore also detected by the sensor signal.
  • Regulated gas pressure control which from a pressure gas container 18, a reversible between this and a vent and a closed position Multi-way valve 20, a control unit 22 for valve actuation and a measuring the height level of the liquid metal column in the filling tube 10, Level sensor 24 connected on the output side to control unit 22 there, the level in the riser 6 and in the mold 8 after the principle of communicating tubes at the same height as in the filling tube 10 lies and is therefore also detected by the sensor
  • the casting plant shown in Fig. 1 operates as follows: Outside the actual one Form filling phases, i.e. when changing the mold 8, the gas pressure in the melting furnace 2, controlled by sensor signals, set so high that the Metal mirror in the filling pipe 10 and thus also in the riser pipe 6 at the level B of the mold-side riser outlet area is held. This State is shown in Fig. 1.
  • the gas pressure in the furnace 2 is increased so that the Casting mold 8 is increasingly filled, the rate of increase of Melt from the control unit 22 with the aid of the level signal from the sensor 24 is monitored until the sensor 24 indicates that the upper mold filling limit A is reached, whereupon the furnace pressure after a predetermined cooling time the mold 8 again to the level B corresponding to the level Pressure value is lowered and the casting can be removed from the mold.
  • a refill of melt is e.g. out a transport pan 28 which can be moved next to the furnace 2 and from which the melt with the help of a gas cartridge 30 via an insertable into the refill opening 14
  • Connection pipe 32 is conveyed into the filling pipe 10 at any time without interruption of the mold-side workflow possible, the free head the melt very much because of the raised filling level in the filling tube 10 is kept low.
  • the compressed gas control 16 ensures in the refill phase for a level signal-dependent readjustment of the furnace pressure, such that only the degree of filling of the melting furnace 2 increases program-guided height level control in the filling pipe 10 and in the riser pipe 6 or the mold 8 is retained unchanged
  • the main difference is a modified gas pressure control 116, through which the liquid metal columns in the filling pipe 110 on the one hand and in the riser pipe 106 and the mold 108, on the other hand, are regulated separately from one another become.
  • the gas space at the upper end of the filling pipe is through the Lid 112 is closed in a pressure-tight manner and is connected to the interior of the oven via a the control unit 122 operated control valve 34, through which the Gas pressure in the filling pipe 110 is continuously between the full furnace internal pressure and the ambient pressure is adjustable.
  • the gas pressure regulator 116 also contains an additional level sensor 36, the liquid metal level immediately on the riser 106 and on the mold 108.
  • the casting process according to the level signal of the sensor system 36, but otherwise analog controlled to the first embodiment, i.e. the liquid metal column in the Riser pipe 106 is constantly at least up to height level B of the riser pipe region raised and is program-guided in the mold filling phase in the mold 108 pressed until the sensor 36 reaches reaching the top Indicates mold fill limit; on the part of the filling pipe 110, however, the gas pressure outside the refill phases via the control valve 34 to the pressure level set inside the furnace so that the metal mirror in the filling pipe 110 the fill level of the molten pool 104 is lowered (FIG.
  • the filling tube furnace system can also be used within the scope of the invention be operated with an inert gas.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Casting Support Devices, Ladles, And Melt Control Thereby (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)

Description

Die Erfindung bezieht sich auf ein Metallgießverfahren und eine Metallgießvorrichtung, insbesondere nach dem Niederdruck-Gießprinzip zur Serienfertigung von Aluminium-Gussteilen, nach dem Oberbegriff des Patentanspruchs 1 bzw. 6.The invention relates to a metal casting method and a metal casting device, especially according to the low pressure casting principle for series production of aluminum castings, according to the preamble of claim 1 or 6.

Bei einer bekannten Gießvorrichtung dieser Art (EP 0 970 767 A1), bei der das Steigrohr selektiv an die Gießform angekoppelt und diese anschließend in der Weise befüllt wird, dass die Metallschmelze aus dem Schmelzeofen unter Niederdruckwirkung in das Steigrohr und von dort in die Gießform gedrückt wird, wird der Metallspiegel im Steigrohr vor jedem Formfüllvorgang mit Hilfe einer Druckgassteuerung einschließlich eines in einem mit dem Steigrohr kommunizierenden Messrohr angeordneten Füllstandsensors auf eine vorgegebene Füllstandshöhe im Bereich des oberen, gießformseitigen Auslassendes des Steigrohrs angehoben, um so das Startniveau des Metallspiegels im Steigrohr für sämtliche Formfüllvorgänge unabhängig vom Füllungsgrad des Schmelzeofens auf gleicher Höhe zu halten. Dabei muss der Schmelzeofen vor jedem Formfüllvorgang, aber auch zum Nachfüllen des Schmelzbads drucklos geschaltet und der eigentliche Gießprozess in dieser Zeit unterbrochen werden, was erhöhte Stillstandzeiten und eine entsprechende Verringerung der durchschnittlichen Produktionsrate zur Folge hat. Problematisch ist jedoch vor allem, dass es, bedingt durch den Nachfüllvorgang, zu einer verstärkten Gasaufnahme und Oxidhautbildung der Schmelze sowie zu höchst unerwünschten Korundablagerungen im Ofen und dadurch zu einer Qualitätseinbuße an den Gussteilen kommt, die im Hinblick auf die strikten Qualitätsanforderungen, wie sie etwa in der Automobilindustrie an Aluminium-Gussteile gestellt werden, nicht hingenommen werden kann.In a known casting device of this type (EP 0 970 767 A1), in which the The riser pipe is selectively coupled to the casting mold and then in the mold Is filled in such a way that the molten metal from the melting furnace under low pressure is pressed into the riser pipe and from there into the mold, the metal level in the riser pipe is checked using a Compressed gas control including one in communication with the riser Measuring tube arranged level sensor to a predetermined Level in the area of the upper, mold-side outlet end of the Riser pipe raised, so the starting level of the metal mirror in the riser pipe for all mold filling processes regardless of the filling level of the melting furnace to keep at the same level. The melting furnace must be in front of everyone Mold filling process, but also depressurized for refilling the weld pool and the actual casting process is interrupted during this time, which increased downtime and a corresponding decrease in average Production rate. However, the main problem is that due to the refilling process, there is an increased gas absorption and formation of oxide skin in the melt and highly undesirable corundum deposits in the oven and thereby a loss of quality to the Castings that come in terms of strict quality requirements, such as they are placed on aluminum castings in the automotive industry, cannot be accepted.

Aufgabe der Erfindung ist es, das Verfahren und die Vorrichtung der eingangs genannten Art so auszubilden, dass die erwähnten, nachfüllbedingten Verunreinigungen des Schmelzbads merklich verringert werden.The object of the invention is the method and the device of the beginning the type mentioned so that the mentioned, refill-related impurities of the weld pool can be significantly reduced.

Diese Aufgabe wird erfindungsgemäß durch das im Patentanspruch 1 gekennzeichnete Verfahren bzw. die im Patentanspruch 6 gekennzeichnete Gießvorrichtung gelöst.According to the invention, this object is characterized by that in claim 1 Method or the casting device characterized in claim 6 solved.

Erfindungsgemäß wird der Metallspiegel im Füllrohr für die Dauer des Nachfüllvorgangs unabhängig vom Füllungsgrad des Ofens auf oder über dem Höhenniveau des Steigrohr-Endbereichs, also deutlich über dem Metallspiegel im Schmelzeofen, gehalten und somit die freie Fallhöhe der Schmelze beim Nachfüllen wesentlich reduziert, mit dem Ergebnis, dass die Oxidhautbildung und Gasaufnahme der Metallschmelze aufgrund des weitgehend verwirbelungsfreien Schmelzeeintrags ebenso wie eine durch aufspritzende Metallpartikel verursachte Korundbildung wirksam unterdrückt werden und dadurch sichergestellt wird, dass das Schmelzbad im Ofen und demzufolge auch die Metallfüllung der Gießform von störenden Verunreinigungen, wie Gas-, Oxidhaut- oder Korundeinschlüssen, freigehalten und die Gussqualität signifikant verbessert wird.According to the invention, the metal level in the filling tube is for the duration of the refilling process regardless of the degree of filling of the furnace at or above the level the end of the riser pipe, i.e. clearly above the metal level in the Melting furnace, and thus the free fall height of the melt at Refilling significantly reduced, with the result that oxide skin formation and gas absorption of the molten metal due to the largely swirl-free Melt entry as well as by spraying metal particles caused corundum formation are effectively suppressed and thereby ensured is that the weld pool in the furnace and consequently also the Metal filling of the mold of disruptive contaminants, such as gas, oxide skin or corundum inclusions, kept free and the casting quality significant is improved.

In weiterer vorteilhafter Ausgestaltung der Erfindung wird der Metallspiegel im Füllrohr nach Anspruch 2 im Hinblick auf eine einfache Niveauregelung während der Nachfüllphase durch eine füllstandssignalabhängige Gasdrucksteuerung des Füllrohr-Ofensystems auf die angegebene Füllstandshöhe gebracht. In a further advantageous embodiment of the invention, the metal mirror in Filling tube according to claim 2 with regard to a simple level control during the refill phase through a gas pressure control that is dependent on the fill level signal of the filling tube furnace system to the specified level.

Wird, wie nach Anspruch 3 bevorzugt, die Metallschmelze beim Formfüllvorgang unter Niederdruckwirkung aus dem Schmelzeofen in eine mit dem Steigrohr selektiv koppelbare Gießform gedrückt, so wird das Füllrohr in besonders bevorzugter Weise ständig unter Umgebungsdruck gehalten und der Gasdruck im Schmelzeofen zwischen den Formfüllphasen kontinuierlich auf einen den Metallspiegel im Füllrohr auf dem Höhenniveau des gießformseitigen Steigrohr-Auslassbereichs haltenden Überdruckwert eingeregelt. Dies bewirkt, dass der Metallspiegel im Füllrohr beim Befüllen der Gießform im gleichen Maß wie in dieser ansteigt, zwischen den Formfüllphasen aber weder im Füll- noch im Steigrohr unter das Höhenniveau des Steigrohr-Auslassbereichs absinkt, so dass der Schmelzeofen jederzeit ohne Unterbrechung der Gießtaktfolge nachgefüllt werden kann, ohne dass das Füllstandsniveau im Steigrohr bei oder nach einem Gießformwechsel auf das Badspiegelniveau des Ofens abfällt und dann durch Erhöhung des Gasdrucks im Ofen erneut angehoben werden muss, wodurch eine äußerst rationelle Druckgassteuerung erzielt wird und die durchschnittlichen Gusstaktzeiten wesentlich verkürzt werden. In diesem Fall wird die Füllstandsmessung im Füllrohr nach Anspruch 4 vorzugsweise auch zur Überwachung und Steuerung des Schmelzeanstiegs in der Gießform bis zum Erreichen der oberen Formfüllgrenze eingesetzt und somit die sonst zu diesem Zweck erforderliche, gesonderte Füllstandsmessung unmittelbar an der Gießform entbehrlich gemacht.As is preferred according to claim 3, the metal melt during the mold filling process under low pressure from the melting furnace into one with the riser selectively coupled mold, so the filling tube is particularly preferably kept constantly under ambient pressure and the gas pressure in the melting furnace between the mold filling phases continuously on one Metal mirror in the filler pipe at the level of the riser outlet area on the mold side maintaining overpressure value adjusted. This causes the Metal mirror in the filling tube when filling the mold to the same extent as in this increases, but between the mold filling phases neither in the filling nor in the Ascending pipe drops below the level of the riser pipe outlet area, see above that the melting furnace is refilled at any time without interrupting the casting cycle can, without the level in the riser at or after changing the mold to the bath level of the furnace and then has to be raised again by increasing the gas pressure in the furnace, whereby an extremely efficient compressed gas control is achieved and the average Cast cycle times can be significantly reduced. In this case the level measurement in the filling tube according to claim 4 preferably also Monitoring and control of the melt rise in the mold up to Reaching the upper mold filling limit and thus the otherwise to this Purpose required, separate level measurement directly on the casting mold made unnecessary.

Nach einer weiteren, ebenfalls besonders zweckmäßigen Verfahrensvariante gemäß Anspruch 5, wonach die Metallschmelze wiederum unter Niederdruckwirkung in eine mit dem Steigrohr selektiv koppelbare Gießform gedrückt wird, wird der Gasdruck oberhalb des Metallspiegels im Füllrohr mit Hilfe eines füllstandssignalabhängig betätigten, einerseits mit dem Umgebungsdruck und andererseits mit dem Ofendruck beaufschlagten 3-Wege-Ventils derart gesteuert, dass das Einfüllniveau im Füllrohr nur für die Dauer der Nachfüllphase auf die Höhe des Steigrohr-Auslassbereichs gebracht, ansonsten aber auf das Metallbadniveau des Ofens abgesenkt wird. Auch hier ist es jederzeit ohne Unterbrechung des Arbeitsprozesses möglich, das Schmelzbad im Ofen auf dem Wege über die dann im Füllrohr angehobene Flüssigmetallsäule nachzufüllen, während der Metallspiegel im Steigrohr unabhängig von dem Nachfüllvorgang beim Befüllen der Gießform bis zur oberen Formfüllgrenze angehoben und bei oder nach einem Gießformwechsel auf der Höhe des Steigrohr-Auslasses gehalten wird. Zusätzlich ergibt sich bei dieser Variante der thermische Vorteil, dass durch das Absenken der Metallschmelze im Füllrohr zwischen den Nachfüllphasen auf einfache Weise verhindert wird, dass sich das Flüssigmetall im Füllrohr zu stark abkühlt und dann an der Füllrohr-Innenwand niederschlägt.According to a further, also particularly expedient process variant according to claim 5, after which the molten metal in turn under low pressure is pressed into a mold which can be selectively coupled to the riser pipe, the gas pressure above the metal level in the fill pipe is dependent on a fill level signal operated, on the one hand with the ambient pressure and on the other hand controlled with the furnace pressure 3-way valve so that the filling level in the filling pipe is only for the duration of the refilling phase Height of the riser outlet area brought, but otherwise to the metal bath level the furnace is lowered. Again, there is no interruption at any time of the work process possible, the melt pool in the furnace on the way over the liquid metal column then raised in the filling tube, while the metal mirror in the riser pipe regardless of the refill process when Filling the mold up to the upper mold filling limit and at or held at the level of the riser outlet after changing the mold becomes. This variant also has the thermal advantage that by lowering the molten metal in the filling pipe between the refill phases is easily prevented that the liquid metal in the The filling pipe cools down too much and then precipitates on the inside of the filling pipe.

Weitere Einzelheiten der Erfindung ergeben sich aus der nachfolgenden, beispielsweisen Beschreibung in Verbindung mit den Zeichnungen. Diese zeigen in stark schematisierter Darstellung:

Fig. 1
ein Ausführungsbeispiel einer erfindungsgemäßen Gießanlage im Schnitt; und
Fig.2
eine der Fig. 1 entsprechende Darstellung eines zweiten Ausführungsbeispiels der Erfindung.
Further details of the invention emerge from the following exemplary description in conjunction with the drawings. These show in a highly schematic representation:
Fig. 1
an embodiment of a casting plant according to the invention in section; and
Fig.2
1 corresponding representation of a second embodiment of the invention.

Die in Fig. 1 gezeigte Gießanlage dient zur Herstellung von Aluminium-Gussteilen nach dem Niederdruckverfahren und enthält einen Schmelzeofen 2 mit einem in das Schmelzbad 4 eintauchenden, über die Ofenoberseite hinausragenden Steigrohr 6 zum Befüllen einer selektiv mit dem oberen, trichterförmig erweiterten Steigrohrende koppelbaren Gießform 8 sowie mit einem ebenfalls in das Metallbad 4 eintauchenden Füllrohr 10, welches am oberen, über die Füllobergrenze A der Gießform 8 hinausragenden Ende durch einen Deckel 12 mit einer Nachfüll- und Entlüftungsöffnung 14 verschlossen ist.The casting plant shown in Fig. 1 is used for the production of aluminum castings according to the low pressure process and contains a melting furnace 2 with an immersion in the melt pool 4, which protrudes beyond the furnace top Riser pipe 6 for filling one selectively with the upper, funnel-shaped extended riser pipe end coupling mold 8 as well as with a likewise in the metal bath 4 immersed filling tube 10, which at the top, on the Filling upper limit A of the mold 8 protruding end through a cover 12 is closed with a refill and vent opening 14.

Der Gasdruck im Ofeninneren wird mit Hilfe einer insgesamt mit 16 bezeichneten Gasdruckregelung einreguliert, welche aus einem Druckgasbehälter 18, einem zwischen diesem und einer Entlüftungs- und einer Schließlage umsteuerbaren Mehrwegeventil 20, einer Steuereinheit 22 zur Ventilbetatigung sowie einem das Höhenniveau der Flüssigmetallsäule im Füllrohr 10 messenden, ausgangsseitig an die Steuereinheit 22 angeschlossenen Füllstandsensor 24 besteht, wobei das Füllstandsniveau im Steigrohr 6 und in der Gießform 8 nach dem Prinzip kommunizierender Röhren auf gleicher Höhe wie im Füllrohr 10 liegt und daher vom Sensorsignal miterfasst wird.The gas pressure inside the furnace is identified with the help of a total of 16 Regulated gas pressure control, which from a pressure gas container 18, a reversible between this and a vent and a closed position Multi-way valve 20, a control unit 22 for valve actuation and a measuring the height level of the liquid metal column in the filling tube 10, Level sensor 24 connected on the output side to control unit 22 there, the level in the riser 6 and in the mold 8 after the principle of communicating tubes at the same height as in the filling tube 10 lies and is therefore also detected by the sensor signal.

Die in Fig. 1 gezeigte Gießanlage arbeitet wie folgt: Außerhalb der eigentlichen Formfüllphasen, also etwa bei einem Wechsel der Gießform 8, wird der Gasdruck im Schmelzeofen 2 sensorsignalgesteuert so hoch eingestellt, dass der Metallspiegel im Füllrohr 10 und somit auch im Steigrohr 6 auf dem Höhenniveau B des gießformseitigen Steigrohr-Auslassbereichs gehalten wird. Dieser Zustand ist in Fig. 1 dargestellt.The casting plant shown in Fig. 1 operates as follows: Outside the actual one Form filling phases, i.e. when changing the mold 8, the gas pressure in the melting furnace 2, controlled by sensor signals, set so high that the Metal mirror in the filling pipe 10 and thus also in the riser pipe 6 at the level B of the mold-side riser outlet area is held. This State is shown in Fig. 1.

Zum Befüllen der Gießform 8 wird der Gasdruck im Ofen 2 erhöht, so dass die Gießform 8 zunehmend befüllt wird, wobei die Anstiegsgeschwindigkeit der Schmelze von der Steuereinheit 22 mit Hilfe des Füllstandssignals des Sensors 24 überwacht wird, bis der Sensor 24 anzeigt, dass die obere Formfüllgrenze A erreicht ist, woraufhin der Ofendruck nach Ablauf einer vorgegebenen Abkühlzeit der Gießform 8 erneut auf den dem Füllstandsniveau B entsprechenden Druckwert abgesenkt wird und das Gussteil entformt werden kann.To fill the mold 8, the gas pressure in the furnace 2 is increased so that the Casting mold 8 is increasingly filled, the rate of increase of Melt from the control unit 22 with the aid of the level signal from the sensor 24 is monitored until the sensor 24 indicates that the upper mold filling limit A is reached, whereupon the furnace pressure after a predetermined cooling time the mold 8 again to the level B corresponding to the level Pressure value is lowered and the casting can be removed from the mold.

Um eine zu starke Abkühlung der über das Schmelzbad 4 angehobenen Flüssigmetallsäule zu verhindern, kann das Steigrohr 6 und eventuell auch das Füllrohr 10 mit einer individuell regelbaren Zusatzheizung 26 versehen sein.To over-cool the liquid metal column raised above the melt pool 4 to prevent the riser pipe 6 and possibly that Filling tube 10 may be provided with an individually controllable additional heater 26.

Mit der beschriebenen Gießanlage ist ein Nachfüllen von Schmelze z.B. aus einer neben den Ofen 2 verfahrbaren Transportpfanne 28, aus der die Schmelze mit Hilfe einer Gaspatrone 30 über ein in die Nachfüllöffnung 14 einführbares Verbindungsrohr 32 in das Füllrohr 10 befördert wird, jederzeit ohne Unterbrechung des gießformseitigen Arbeitsablaufs möglich, wobei die freie Fallhöhe der Schmelze wegen des angehobenen Einfüllniveaus im Füllrohr 10 sehr gering gehalten wird. Dabei sorgt die Druckgasregelung 16 in der Nachfüllphase für eine füllstandssignalabhängige Nachregelung des Ofendrucks, derart, dass sich lediglich der Füllungsgrad des Schmelzeofens 2 erhöht, die programmgeführte Höhenniveauregelung im Füllrohr 10 sowie im Steigrohr 6 bzw. der Gießform 8 jedoch unverändert beibehalten wirdWith the casting system described, a refill of melt is e.g. out a transport pan 28 which can be moved next to the furnace 2 and from which the melt with the help of a gas cartridge 30 via an insertable into the refill opening 14 Connection pipe 32 is conveyed into the filling pipe 10 at any time without interruption of the mold-side workflow possible, the free head the melt very much because of the raised filling level in the filling tube 10 is kept low. The compressed gas control 16 ensures in the refill phase for a level signal-dependent readjustment of the furnace pressure, such that only the degree of filling of the melting furnace 2 increases program-guided height level control in the filling pipe 10 and in the riser pipe 6 or the mold 8 is retained unchanged

Die Gießanlage nach Fig. 2, wo die dem ersten Ausführungsbeispiel entsprechenden Komponenten durch ein um 100 erhöhtes Bezugszeichen gekennzeichnet sind, besitzt als Hauptunterschied eine modifizierte Gasdruckregelung 116, durch die die Flüssigmetallsäulen im Füllrohr 110 einerseits und im Steigrohr 106 bzw. der Gießform 108 andererseits getrennt voneinander eingeregelt werden. Zu diesem Zweck ist der Gasraum am oberen Füllrohrende durch den Deckel 112 druckdicht verschlossen und mit dem Ofeninnenraum über ein von der Steuereinheit 122 betätigtes Steuerventil 34 verbunden, durch welches der Gasdruck im Füllrohr 110 stufenlos zwischen dem vollen Ofen-Innendruck und dem Umgebungsdruck einstellbar ist. Ferner enthält die Gasdruckregelung 116 eine zusätzliche Füllstandsensorik 36, die den Flüssigmetallstand unmittelbar am Steigrohr 106 und an der Gießform 108 misst.2, where the corresponding to the first embodiment Components identified by a reference numeral increased by 100 The main difference is a modified gas pressure control 116, through which the liquid metal columns in the filling pipe 110 on the one hand and in the riser pipe 106 and the mold 108, on the other hand, are regulated separately from one another become. For this purpose the gas space at the upper end of the filling pipe is through the Lid 112 is closed in a pressure-tight manner and is connected to the interior of the oven via a the control unit 122 operated control valve 34, through which the Gas pressure in the filling pipe 110 is continuously between the full furnace internal pressure and the ambient pressure is adjustable. The gas pressure regulator 116 also contains an additional level sensor 36, the liquid metal level immediately on the riser 106 and on the mold 108.

Auf Seiten des Steigrohrs 106 und der Gießform 108 wird der Gießprozess nach Maßgabe des Füllstandssignals der Sensorik 36, im Übrigen aber analog zum ersten Ausführungsbeispiel gesteuert, d.h. die Flüssigmetallsäule im Steigrohr 106 ist ständig zumindest bis zum Höhenniveau B des Steigrohr-Ausfassbereichs angehoben und wird in der Formfüllphase programmgeführt in die Gießform 108 gedrückt, bis die Sensorik 36 das Erreichen der oberen Formfüllgrenze anzeigt; auf Seiten des Füllrohrs 110 hingegen wird der Gasdruck außerhalb der Nachfüllphasen über das Steuerventil 34 auf das Druckniveau im Ofeninneren eingestellt, so dass der Metallspiegel im Füllrohr 110 auf das Füllstandsniveau des Schmelzbads 104 abgesenkt ist (Fig. 2), während das Füllrohr 110 für den Nachfüllvorgang mit Hilfe des Steuerventils 34 soweit druckentlastet wird, dass die Flüssigmetallsäule im Füllrohr 110 auf das Steigrohr-Auslassniveau B ansteigt. Anschließend wird das Verbindungsstück 38 mit dem entsprechenden Verbindungsstück 40 der Transportpfanne 128 verkoppelt, das Ventil 42 geöffnet und die gewünschte Schmelzemenge nachgefüllt, wobei das Einfüllniveau durch Nachregelung des Füllrohrdrucks konstant auf dem Steigrohr-Auslassniveau B gehalten und die durch die Nachfüllmenge verursachte Füllstandsänderung im Ofen 102 von der Gasdruckregelung 116 insoweit ausgeglichen wird, dass der gießformseitige Arbeitstakt hiervon nicht beeinflusst wird. Nach Beendigung des Nachfüllvorgangs wird das Ventil 42 geschlossen und der Gasraum im Füllrohr 110 erneut mit dem vollen Ofendruck beaufschlagt. Ansonsten ist die Bau- und Betriebsweise der Gießanlage nach Fig. 2 die gleiche wie die des ersten Ausführungsbeispiels.On the part of the riser pipe 106 and the mold 108, the casting process according to the level signal of the sensor system 36, but otherwise analog controlled to the first embodiment, i.e. the liquid metal column in the Riser pipe 106 is constantly at least up to height level B of the riser pipe region raised and is program-guided in the mold filling phase in the mold 108 pressed until the sensor 36 reaches reaching the top Indicates mold fill limit; on the part of the filling pipe 110, however, the gas pressure outside the refill phases via the control valve 34 to the pressure level set inside the furnace so that the metal mirror in the filling pipe 110 the fill level of the molten pool 104 is lowered (FIG. 2) while the filling pipe 110 for the refilling process with the help of the control valve 34 so far is depressurized that the liquid metal column in the fill tube 110 to the riser outlet level B increases. Then the connecting piece 38 with couples the corresponding connector 40 of the transport pan 128, valve 42 opened and the desired amount of melt refilled, the filling level is kept constant by readjusting the filling pipe pressure the riser outlet level B and the refill quantity Level change caused in the furnace 102 by the gas pressure regulator 116 in so far as it is compensated that the mold-side work cycle of this is not being affected. After the refilling process has ended, the valve 42 closed and the gas space in the filling pipe 110 again at full furnace pressure applied. Otherwise, the construction and operation of the casting system 2 the same as that of the first embodiment.

Anstatt mit Luft kann das Füllrohr-Ofensystem im Rahmen der Erfindung auch mit einem Inertgas betrieben werden.Instead of using air, the filling tube furnace system can also be used within the scope of the invention be operated with an inert gas.

Claims (6)

  1. A method of metal casting, especially for series production of aluminium castings at low pressure, wherein the metal melt is introduced into the casting mould from a melting furnace periodically refillable through a filling tube, with interposition of a rising pipe dipping into the melt, characterised in that during the phase of refilling the melting furnace the level in the filling tube is continuously measured and during the entire refilling process the level of metal in the filling tube, in accordance with the filling-level signal, is kept at a height at least equal to that of the outlet region of the rising pipe near the casting mould.
  2. A method according to claim 1, characterised in that the level of metal in the filling tube is kept at the said height during the refilling phase by a means for controlling the gas pressure in the filling-tube and furnace system in dependence on the filling-level signal.
  3. A method according to claim 2, wherein during the process of filling the mould, the metal melt is driven under low pressure out of the melting furnace into a casting mould which can be selectively coupled to the rising pipe, characterised in that the filling tube is constantly kept at ambient pressure, and between the mould-filling phases the gas pressure in the melting furnace is continuously adjusted to an excess pressure keeping the level of metal in the filling tube at the same height as the outlet region of the rising pipe near the casting mould.
  4. A method according to claim 3, characterised in that the time of reaching the top mould-filling level is determined via the filling height measured in the filling tube.
  5. A method according to claim 2, wherein during the process of filling the mould, the metal melt is driven under low pressure out of the melting furnace into a casting mould which can be selectively coupled to the rising pipe, characterised in that the gas space above the surface of the metal in the filling tube, under valve control, is subjected to the gas pressure in the melting furnace in between the refilling phases and is relieved of pressure during the entire refilling process in accordance with the filling-level signal until the level of metal in the filling tube rises to the same height as in the outlet region of the rising pipe near the mould.
  6. A device for casting metal, especially for series production of aluminium castings at low pressure, comprising
    a melting furnace (2; 102) containing a metal melt (4; 104),
    a rising pipe (6; 106) dipping into the metal melt in the melting furnace and transferring the melt to the casting mould (8; 108),
    a filling tube (10; 110) likewise dipping into the metal bath, for periodically filling the melting furnace,
    a sensor (24; 124) for measuring the level of melt in the filling tube, and
    a sensor-controlled means (16, 116) for adjusting the gas pressure in the filling-tube and furnace system and keeping the level of metal in the filling tube during the refilling process at a height at least equal to the level (B) in the outlet region of the rising pipe near the mould.
EP01126259A 2000-12-08 2001-11-06 Process and device for metalcasting Expired - Lifetime EP1213070B1 (en)

Applications Claiming Priority (2)

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DE10061026A DE10061026A1 (en) 2000-12-08 2000-12-08 Metal casting process and device
DE10061026 2000-12-08

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EP1213070A3 EP1213070A3 (en) 2003-01-29
EP1213070B1 true EP1213070B1 (en) 2004-07-07

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DE102012008458A1 (en) * 2012-04-24 2013-10-24 Adam Handerek Reactor for gasifying and / or purifying a starting material
CN113333715B (en) * 2021-05-28 2022-11-04 重庆长安汽车股份有限公司 Low-pressure casting mold-filling pressure curve design method based on back pressure

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE571806C (en) * 1931-09-02 1933-03-06 Aeg Device for the production of permanent mold casting by introducing the liquid metal into the permanent mold from a closed melting vessel using compressed air
DE2128425A1 (en) * 1970-08-21 1973-01-04 Friedhelm Dipl Ing Kahn Metal die casting machine - working on u-tube principle using melt feed
BG22157A1 (en) * 1975-10-27 1977-05-20
FR2382298A1 (en) * 1977-03-01 1978-09-29 Renault LOW PRESSURE LIQUID METAL CASTING DEVICE
FR2605913A1 (en) * 1986-10-31 1988-05-06 Pechiney Aluminium METHOD FOR PRESSURIZED MOLDING OF METALLIC PARTS CONTAINING CERAMIC FIBERS
DE3924775C1 (en) * 1989-07-26 1990-03-29 Alcan Deutschland Gmbh, 3400 Goettingen, De
ATE166011T1 (en) * 1992-11-20 1998-05-15 Erana Agustin Arana DEVICE FOR CASTING NON-FERROUS METALS IN SAND MOLDS USING PRESSURE
DE4332760A1 (en) * 1993-09-25 1995-03-30 Klaus Doehrer Method for the operation of a low-pressure metal-casting apparatus and a low-pressure metal-casting apparatus for this purpose
GB9323248D0 (en) * 1993-11-11 1994-01-05 Hi Tec Metals R & D Ltd A casting apparatus and method
JPH0743523U (en) * 1993-12-28 1995-08-22 東亜医用電子株式会社 Cuvette
EP0970767A1 (en) * 1998-05-07 2000-01-12 Georg Fischer Disa A/S Method and apparatus for casting metal articles with counter-gravity supply of metal to moulds
GB9813826D0 (en) * 1998-06-27 1998-08-26 Campbell John Dispensing apparatus and method
DE19832192B4 (en) * 1998-07-17 2010-11-04 Audi Ag Casting plant and method for feeding molten metal to a filling chamber of a casting plant
DE19935357C1 (en) * 1999-07-29 2001-05-10 Wagner Heinrich Sinto Masch Casting device for a foundry molding plant

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EP1213070A3 (en) 2003-01-29
DE10061026A1 (en) 2002-06-13
EP1213070A2 (en) 2002-06-12
DE50102788D1 (en) 2004-08-12

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