Patent ID: 7534390

Claim:
A tuyere device for introducing gaseous media under a liquid-metal layer, comprising; a nest block made of refractory material, said block being provided with a sleeve incorporated in the block including coaxial metal tubes defining at least one central operating channel and at least one annular operating channel which are arranged on a first side of the block for introduction into liquid metal, and are separately connected to inlets for supplying gaseous media to the liquid metal on an opposite second side of the block; said coaxial metal tubes along their length consisting of two interconnected sections having different diameters, the first section being at the first side of the block and having a smaller diameter and being for supplying the gaseous media to the liquid metal and the second section being at the second side of the block and having a larger diameter than said first section and being connected to gas supply inlets for separately supplying the gaseous media to the operating channels of the first section; the second section including an additional central metal tube defining an annular operating channel only with an inner one of the coaxial metal tubes, the central tube of said second section being closed on both ends thereof and filled with a refractory material, gaps of said annular operating channels in said second section being capillaries for the liquid metal.