Apparatus for storing and dropping expendable bof sensors

Abstract

A sensor dropper for storing, shielding and dropping sensors into a BOF vessel. The sensor dropper includes a support frame to move the stored sensors toward or away from a sensor drop path leading into said BOF vessel, a dropper assembly supported on the support frame for storing and releasing sensors into the sensor drop path to the BOF, and a shield gate to protect the sensor dropper and stored sensors from BOF fume. The dropper assembly includes a plurality of storage and release mechanisms and corresponding shear mechanisms. Each storage and release mechanism includes a threaded sensor support shaft from which a stored sensor is suspended and dropped into the sensor drop path when the threads of the sensor support shaft are rotated in an outward direction, and each shear mechanism includes a shear blade housed within a tubular cutter having outer shear blades to sever an electrical sensor cable when the inner shear blade is rotated past the outer shear blades. The shield gate is rotatably mounted at a location along the sensor drop path between the dropper assembly and includes a counterweight to hold shield gate in a closed position. The counterweight is balanced to allow the shield gate to rotate to an open position upon impact from a dropped sensor and return to the closed position after the dropped sensor falls from the shield gate into the BOF vessel.