Jet performance of converter oxygen lance nozzle throughout its operational lifespan

During the steelmaking process, the oxygen lance nozzle undergoes progressive wear with increasing blowing cycles, leading to deviations from its designed operational parameters and consequent degradation in blowing efficiency. This study presents a comprehensive investigation into the jet characteristics of a 5-hole oxygen lance nozzle employed in a 120-ton converter, with particular emphasis on analyzing the nozzle’s wear progression throughout its service life. Through systematic examination of the dynamic behavior and energy evolution of nozzle jets at varying wear stages, this research provides critical insights for optimizing industrial smelting operations. The experimental results demonstrate that nozzle wear significantly influences jet characteristics. As wear progresses, the nozzle exhibits an increased propensity for generating intense shock waves and expansion waves. Furthermore, the study reveals a direct correlation between the degree of nozzle wear and two key parameters: exit velocity and kinetic energy loss rate, both of which show marked increases. However, within the initial 120 heat cycles, the centerline velocity at a standardized measurement point 600 mm from the nozzle exit, along with the jet’s kinetic energy loss rate, remains relatively stable, showing minimal variation. Beyond this threshold, at a distance of 600 mm from the nozzle outlet, the centerline velocity of the stabilized jet experiences a measurable decrease, ranging from 2.08% to 5.29% compared to the performance of an unworn nozzle. These findings provide quantitative evidence of the relationship between nozzle wear and jet performance characteristics, offering valuable data for optimizing nozzle replacement schedules and maintaining operational efficiency in converter steelmaking processes.