Patent Number: 6,309,442

Title: Refractory material sensor for determining level of molten metal and slagand method of using

Abstract: An apparatus and method for indexing the slag-metal interface level in ametallurgical container uses an insulating refractory brick having aplurality of embedded conductor wires. Distal ends of the conductor wiresare exposed at know, fixed distances from the distal end of the stick andflush with the brick face. The proximal ends of the conductor wiresprotrude a predetermined distance from the proximal end of the brick. Thebrick is attached to the inner lining of the container at a known distancefrom the floor of the container. The proximal wire ends are joined by asuitable connector to a signal-transmission cable containing a matchingnumber of individual conductors, which is connected to a multi-channelvoltmeter. Output from the multi-channel voltmeter can be input to amultiple-channel PC-based signal interpretation instrument. Duringoperation the voltage output of each sensor circuit is continuouslymonitored. A multiple-channel impedance-measuring device is alsoincorporated into each sensor circuit to continuously monitor individualcircuit impedance without disturbing the internally generated DC voltagesignal, ensuring that the value of the displayed voltage accuratelyreflects sensor output and not some unrelated property of theelectromagnetic environment. If the circuit impedance falls outsidepredetermined limits, the system is disabled and cannot be reset,providing an indication of the need to take alternative action.

Inventors: Usher; John D. (Beaver Falls, PA)


International Classification:

Expiration Date: 10/32013