IT1279092B1 - Lance for blowing fluid-state substances inside furnaces, partic. for steel prodn. - comprises elongated body inside which are provided ducts which lead out of body proximate to one of its longitudinal ends and are connected by couplings to fluid substances feed device - Google Patents

Abstract

Lance (1, 101) for blowing fluids inside furnaces, particularly for steel production, comprises: an elongated body (2, 102) in which at least two ducts (3, 4, 104, 105) are formed which lead outside body near to one of its longitudinal ends, the at least two ducts being connected by couplings (5, 6, 105, 106, 107) to means for feeding fluids to be blown inside the furnace; and a chamber for the circulation of a coolant, the chamber being formed inside body near to end. Outlets of two ducts are orientated in two delivery directions converging outside the lance. The at least two ducts comprise at least three ducts: a first duct, a second duct, and a third duct, the first duct running, at least proximate to its end that leads outside body, inside the second duct and runs coaxially with the second duct. Outlet of all three ducts are orientated along two delivery directions converging outside body. Two delivery directions intersect at an angle substantially between 30[deg] and 40[deg], or can mutually intersect at an angle of 35[deg]. At least longitudinal end of body is made of a metallic material having high thermal conductivity. Chamber for circulating a coolant comprises a delivery portion that is adjacent to the internal skin of body and a return portion that lies inside delivery portion. Ducts are formed by tubular bodies inserted in body.