异型坯连铸机中间包热换的研究与实践

Research and practice of heat exchange in tundish of the shaped blank continuous caster

钢铁行业采用中间包热换技术来减少铸机的停机时间,提高产量,以此来达到降本增效的目的。当前连铸机中无法实现中间包热换的机型有异型坯连铸机、连铸连轧等铸机类型。异型坯铸坯结构包含有方坯、板坯、圆坯的特性,结构复杂,且比表面积大,在二冷段就完全凝固。若按照其他机型热换方式进行热换,造成铸坯过度冷却,表面温度降低,造成铸机卧坯。利用柏拉图分析方法,分析出影响异型坯热换的主要因素,如中间包热换时间过长、冷却水量大、工艺装置不合理。实践过程中通过优化调整一冷水、二冷水参数及改进工艺装置,最终实现了中间包热换工艺,提高了铸机的作业率。

Tundish heat exchange technology is adopted in the iron and steel industry to reduce the downtime of the casting machine and increase the output,so as to achieve the purpose of reducing cost and increasing efficiency. At present,there are some types of casting machines such as special-beam blank casting machine and continuous casting and rolling machine which can’t realize heat exchange of tundish. The structure of beam blank includes square billet,slab and round billet which is very complex. Its specific surface area is bigger and totally frozen in secondary cooling zone. If the heat exchange is carried out according to other casting machine’s models,the billet will be excessively cooled and the surface temperature will decrease,resulting in the billet lying on the casting machine. Platonic analysis method is used to analysis the main factors affecting heat transfer in beam blank,such as overtime in tundish heat exchange,large cooling water and unreasonable process device. The practice process is adjusted by optimizing the parameters of first and secondary cooling water and improve process device,finally realizes the tundish heat exchange in process and improve the operation efficiency of casting machine.