DEVELOPMENT OF FLOW CONTROL DEVICE FOR SIX-STRAND BILLET CASTER TUNDISH AT DURGAPUR STEEL PLANT

摘要

Strand breakout and nozzle clogging in caster affect the productivity. In billet caster at Durgapur Steel Plant (DSP) breakout frequency is more in inner nozzles while clogging is more in outer nozzles. Fluid flow profile in tundish was studied through cold model experiments to understand the reasons for low strand availability and find out optimum solutions. Flow profile in existing tundish indicated large difference in residence time between nozzles and existence of flow short circuiting and dead region. Various flow control devices were tested t6 improve the situation. Asymmetric baffle was found to be most effective. The residence time distribution uniformity between nozzles increased, short circuiting eliminated and dead volume reduced significantly. Based on the results of cold model studies, asymmetric baffle was designed for actual trials and manufactured using low moisture castable having high temperature strength and erosion resistant properties to withstand sequence of minimum five heats. Application of asymmetric baffle reduced temperature difference between outer and inner outlets to <=3 deg C. Consequently strand losses due to breakout. (inner strand) and clogging (outer strand) were largely reduced.