Bulging of 165 mm x 280 mm and 165 mm x 240 mm blooms easily occurs for partly R6 and R8 caster without secondary cooling pinch roll section casting as increasing cast speed. Based on analysis and test
it is obtained that with adjusting and increasing water rate at narrow side
the bulging of cast bloom improves obviously. With derived maximum stress formula at comer of bloom and adjusting solidification coefficient K
the deformation of each side of bloom is prevented to improve the bulging phenomena of bloom.