Refractory material sensor for determining level of molten metal and slag and method of using

Abstract

An apparatus and method for indexing the slag-metal interface level in a metallurgical container uses an insulating refractory brick having a plurality of embedded conductor wires. Distal ends of the conductor wires are exposed at know, fixed distances from the distal end of the stick and flush with the brick face. The proximal ends of the conductor wires protrude a predetermined distance from the proximal end of the brick. The brick is attached to the inner lining of the container at a known distance from the floor of the container. The proximal wire ends are joined by a suitable connector to a signal-transmission cable containing a matching number of individual conductors, which is connected to a multi-channel voltmeter. Output from the multi-channel voltmeter can be input to a multiple-channel PC-based signal interpretation instrument. During operation the voltage output of each sensor circuit is continuously monitored. A multiple-channel impedance-measuring device is also incorporated into each sensor circuit to continuously monitor individual circuit impedance without disturbing the internally generated DC voltage signal, ensuring that the value of the displayed voltage accurately reflects sensor output and not some unrelated property of the electromagnetic environment. If the circuit impedance falls outside predetermined limits, the system is disabled and cannot be reset, providing an indication of the need to take alternative action.