Abstract: Based on the theoretical research and production practice, the causes of longitudinal crack breakout and sticking breakout was discussed from
of the composition of molten steel, the degree of superheat, the taper of crystallizer, the casting powder of crystallizer, and more aspects.
After some regulatory  measure was adopted, such as   carbon,sulphur content and superheat control  of  liquid steel,  heat transfer control of crystallizer, weak cold control of the secondary cooling zone, and flow field control of crystallizer, the breakout rate of container steel produced by the thin slab continuous casting process has been reduced from 1.25 % to 0.35 %.

Key words: CSP, caster, container steel, causes of breakout, regulatory measure