The component distribution is periodicity.The surface coarseness of graphite sleeve affects badly on the surface quality of billet.Crack will be increased with the abrasion of graphite sleeve.

• 结晶器中石墨套的表面光洁度对铸坯的表面质量和裂纹缺陷的产生有重要影响,石墨套磨损将导致裂纹缺陷的增加。