DEVELOPMENT OF DESULPHURIZATION LANCE AN INDIAN EXPERIENCE

摘要

Desulphurization is a part of pre-treatment of hot metal before it goes to the steel converter and it is done to reduce the refining load on the converter. Desulphurization is carried out by injecting fine CaC_2 with or without Mg metal powder into the hot metal in torpedo ladle or transfer ladle using a lance. The lance has a composite structure consisting of a long cylindrical steel pipe at its core with a refractory castable shell held together by suitable anchors and reinforcements.The lance, during operation, experiences thermal, mechanical and chemical load but its wear and failure are controlled essentially by thermo-mechanical factors. In the present work, an analysis of thermal and mechanical stresses generated during lancing-waiting-lancing cycles is used for developing a suitable design of hard ware including anchoring and reinforcement systems along with a refractory castable satisfying the thermo-mechanical property requirements. The performance is continuously monitored and the observed behaviour is analysed to further improve the castable material design and adjust the thickness profile of the lance.