LANCE FOR METAL BLOWING Russian patent published in 2001 - IPC

FIELD: metallurgy, particularly, treatment of liquid metal with gas for improvement of its quality and increase of yield of steel. SUBSTANCE: lance jet resonator is made of contracting-expanding nozzle and vibration resonator. The latter is located square to axis of gas-supplying route and made for direct action of elastic vibrations from zone of their generation onto gas flow in gas-supplying route whose end part is located opposite to outlet nozzle of lance and made in the form of spherical reflector so that zone of generation of gas vibration coincides with focal point of spherical reflector. Resonator free volume V_r is determined from relationship 25d2n

<V_r<1550d²s, where d_n is exit diameter of contracting-expanding nozzle. Lance outlet nozzle is circular. Application of claimed lance allows reduction of defects (internal scabs, cavities, external scabs) and increased yield of good product by 3.6 kg/t of steel in manufacture of hot-rolled pipes. EFFECT: reduced aerodynamic resistance of supplying route and lance cross-section, and more efficient use of gas supply to increase quality of metal. 1 dwg