Multi-grooved channel design in continuous casting mold for enhancing heat transfer efficiency considering pressure drop and flow rate loss

Abstract

An efficient, speedy, multi-grooved (ESMG) mold was designed and manufactured for optimization to address issues such as low heat transfer rate, slow casting speed, and quality defects in traditional continuous casting molds. The flow resistance mechanism of multi-grooved channels with varying parameters was investigated by considering the ESMG geometric model, the convective heat transfer characteristic variation trends were revealed with different channel designs. Considering constraints of the dimensional chain and supply pressure, variation trends and mechanisms of the pressure drop, flow rate loss, and convective heat transfer coefficient of the ESMG mold were explored using multiple channel variables. Based on the numerical model of the ESMG channel, temperature variation trends in the copper mold were verified by comparison with relevant literature data, supporting the convective-heat-transfer model and variation trends of the ESMG mold. A high-efficiency heat-transfer ESMG assembly that casts U71Mn high-carbon large rectangular billets was fabricated, achieving a closed-loop dimensional chain and replacing traditional molds. Experimental validation on the continuous casting machine (CCM) proved directly that redesigning the ESMG mold cooling channel improved heat transfer efficiency and reduced CO emissions. After 504 h on the CCM, the ESMG mold casting speed increased from 1.1 to 1.6 m/min, the heat transfer efficiency was 17.6% higher than that of traditional molds and CO emissions were estimated to decrease by 31.2%. The billets produced by the ESMG mold had no quality defects in shape or surface with the original casting conditions, which provided enhanced support for accelerating continuous casting lines.