Installation for filling a mould with liquid metal and process employing this installation

Abstract

The installation according to the invention comprises at least one mould, a vessel intended to receive the liquid metal and means for directly determining the evolution of the level of molten metal in the impression of the mould. These determination means comprise means for detecting the presence of this liquid metal in the impression, particularly of electromagnetic nature, which are adapted to penetrate at least partially in the interior volume of this impression.

1 . Installation for filling a mould with liquid metal, comprising: 
 at least one mould comprising a casting bowl, a feed channel, as well as at least one impression connected to said bowl by said channel,    a vessel intended to receive the liquid metal having to be cast into the mould; and    means for directly determining the evolution of the level of molten metal in the impression, these determination means comprising means for detecting the presence of this liquid metal in the impression, these detection means being adapted to penetrate at least partially in the interior volume of this impression.    
     
     
         2 . The installation of  claim 1 , wherein the detection means are of electromagnetic nature.  
     
     
         3 . The installation of  claim 2 , wherein the determination means comprise means for creating an electromagnetic field, of which lines of field form said detection means, these lines of field being able to be disturbed by the liquid metal present in the impression.  
     
     
         4 . The installation of  claim 3 , wherein the means for creating the electromagnetic field comprise at least one emitter coil, an electric generator adapted to excite this emitter coil, as well as at least one receiver coil adapted to cooperate with said emitter coil.  
     
     
         5 . The installation of  claim 4 , wherein two receiver coils are provided, a first receiver coil being placed between the emitter coil and the mould, while the other receiver coil is placed opposite the emitter coil with respect to the mould.  
     
     
         6 . The installation of  claim 3 , wherein the determination means also comprise means adapted to transform the intensity of the disturbance undergone by said lines of field into an analog signal representative of the evolution of the level of liquid metal in the impression, this analog signal corresponding for example to the evolution of a voltage as a function of the level of filling of the mould.  
     
     
         7 . The installation of  claim 6 , wherein the determination means also comprise means for obtaining an instantaneous curve, from said analog signal, representative of the evolution of the level of molten metal in the impression, as well as means for comparing this instantaneous curve with a reference curve, while means are, in addition, provided for controlling the flowrate of molten metal poured from the vessel, in the event of the instantaneous curve differing from the reference curve to an inadmissible extent.  
     
     
         8 . The installation of  claim 7 , wherein the control means are adapted to actuate a mobile stopper with which the vessel is equipped.  
     
     
         9 . Process for employing the installation of  claim 3 , comprising the following steps of: 
 actuating the means for creating the electromagnetic field so as to generate lines of field penetrating at least partially in the interior volume of the impression; and    determining the evolution of the level of liquid metal in the impression, as a function of the intensity of the disturbance undergone by these lines of field.    
     
     
         10 . The process of  claim 9 , wherein said instantaneous curve and said reference curve are compared and the flowrate of liquid metal poured from the vessel is modified if the difference between this instantaneous curve and this reference curve is inadmissible.  
     
     
         11 . The process of  claim 10 , wherein the flowrate of liquid metal is modified by displacing said stopper.  
     
     
         12 . The process of  claim 9 , wherein a predetermined threshold of the impression is chosen, the instant is detected at which the level of liquid metal reaches this threshold, a latent period is allowed to lapse, depending in particular on the instantaneous value of the flowrate of molten metal poured from the vessel, and the admission of liquid metal in the mould is stopped at the end of this latent period.