METHOD OF RAPIDLY ESTIMATING CONDITION OF LANCE WHEN BLOWING THROUGH THE SMELT IN LADLE Russian patent published in 1998 - IPC

FIELD: metallurgy. SUBSTANCE: condition of lance is rapidly estimated by analyzing dynamics of variation in smoothed time dependence of pressure of gas entering lance. In this dependence, as process advances, one searches for absolute minimum over the period from lowering lance in its lower position. Difference Δ₁(i) between this minimum and the last value, difference Δ₂(i) between last value and preceding one, and difference Δ₃(j) between the first and last absolute minima are then found. If Δ₂(i) = 0 and Δ₁(i) = 0, lack of metallization of lance nozzle is stated. Increase of metallization of lance nozzle s(i) is recorded in case Δ₂(i)>0,. If Δ₂(i) = 0 and Δ₁(i)>0, stabilization 3(i), and, if Δ₂(i)<0 and Δ₁(i)>0, reduction 3(i) are recorded. Shortening of lance Δ₁(i)<0 is recorded when Δl(j). Numerical values 3(i) and Δl(j) are found in direct dependencies on Δ_i(i) and Δ₃(j), respectively. When 3(i) and Δl(j) exceed their allowable values, failure of lance is stated. EFFECT: facilitated process control. 2 dwg