连铸机二冷配水对铸坯鼓肚的改善

Improvement of Bloom Bulging by Distribution of Secondary Cooling Water of Caster

部分生产165 mm×280 mm、165 mm×240 mm的R6和R8连铸机,没有二冷夹持段,在提高拉速后铸坯易出现鼓肚现象。通过分析和试验,得出调整和适当增加窄边水量,明显改善了铸坯的鼓肚。通过推导出的坯壳角部最大受力公式,调整凝固系数K值,可防止铸坯各边的变形,以改善铸坯鼓肚现象。

Bulging of 165 Mini× 280 nun and 165 mm×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 maxi- mum stress formula at corner of bloom and adjusting solidification coefficient K, the deformation of each side of bloom is prevented to improve the bulging phenomena of bloom.