Water-Cooled Furnace Elements

Abstract

Elements whose durability significantly affects productivity and cost effectiveness of the furnaces’ operation and even the selection of directions of the heat intensification are reviewed. General laws of thermal performance of elements; processes defining their durability. Reasons for wearing. The necessity of avoiding the cooling in the mode of water local boiling. Experimental data on maximal densities of heat fluxes perceived by elements at the EAF freeboard. An idea of the critical element zone. Calculation formulae for determination of minimal required water flow rate, temperatures of external surface and that flown around by water, and hydraulic resistance of water channels. General diagram of new element calculation. Calculations of thermal performance for both a mobile oxygen tuyere and an element with pipes cast into copper or with channels for water passing. Jet cooling of stationary tuyere for a deep oxygen blowing of the bath providing for the removal of heat fluxes with the density up to 10 MW/m² without water local boiling due to the increase in the convective heat transfer coefficient α up to 150 kW/m² × °C.