Abstract: A lance head for a refining lance, comprising, a lance head bottom member, a plurality of expanding nozzles connected to the bottom member, a supply line associated with the bottom member for supplying coolant thereto, a return line associated with the supply line for channeling coolant away from the bottom member and a flow guide member connected between the supply line and the return line. The flow guide member extends across the plurality of expanding nozzles and includes a surface facing the bottom member defining a coolant passage therewith. The flow guide member surface is concave in the area of the nozzles so that the cross-sectional area of the flow passage is constant as coolant flows past the nozzles. The edge of the flow guide member surface extends beyond the nozzles and at an oblique angle to a central portion of the bottom member between the nozzles.

Abstract: Oxygen or oxygen-containing gas is blown onto a molten crude iron bath inside a converter. A layer of slag or metal-slag emulsion forms atop the molten crude iron bath and grows in height during the course of the refining reaction. The height of such layer is indirectly determined by detecting an electrical characteristic of the layer. The layer of slag or metal-slag emulsion is made to serve as the dielectric of a capacitive reactive and/or as the flux-permeable part of an inductive reactance, and such reactance, or a plurality of such reactances, form part of a resonant circuit.