Research on the Optimization of the Impact of Flame Cutting Costs of Continuous Casting Billets

本文针对马鞍山钢铁公司长材2#连铸机火焰切割燃气成本较高的问题，通过设备改造与工艺优化实现降本增效。研究分析了燃气单耗的影响因素，提出基于拉瓦尔管割嘴的优化方案。通过改造长明火供气系统及采用收缩扩张结构的拉瓦尔管割嘴，提升燃气燃烧效率与气流速度(超音速)，并结合切割速度优化实验，实现燃气单耗降至0.11 kg/t。实验表明，改造后切割时间缩短13~19秒，表面粗糙度(Ra)由原46.5 μm降至8.7 μm，且挂渣程度显著改善，并通过t检验验证了改进效果的显著性。研究为连铸坯火焰切割的精细化成本控制提供了理论与实践依据，具有工业推广价值。This study addresses the issue of high gas consumption in flame cutting at Ma’anshan Iron and Steel Co. Ltd.’s long-materials No. 2 Continuous Casting Machine by implementing equipment modifications and process optimizations to achieve cost reduction and efficiency improvement. Through analysis of factors affecting gas consumption, an optimization plan based on a Laval nozzle was proposed. By modifying the pilot flame gas supply system and adopting a converging-diverging Laval nozzle, gas combustion efficiency and gas flow velocity (supersonic) were improved. Combined with cutting speed optimization experiments, gas consumption was reduced to 0.11 kg/t. Experimental results showed that cutting time was shortened by 13~19 seconds, surface roughness (Ra) decreased from 46.5 μm to 8.7 μm, and slag adhesion was significantly improved. A t-test further validated the significance of the improvements. This research provides theoretical and practical foundations for refined cost control in continuous casting billet flame cutting and demonstrates industrial promotion value.