Abstract：High casting speed is the necessary condition for realizing low-cost and green production of deformed steel bars in billet caster, and it is the embodiment of the overall technological progress of continuous casting. After the billet caster of Fujian Sangang steelmaking plant has been transformed with high efficiency, casting speed with 160 mm×160 mm section deformed steel has the ability to reach 6.0 m/min. When screw thread steel with 160 mm×160 mm section billet is increased to 4.1 m/min in the production process, steel leakage and billet breaking accidents occur. Through comprehensive analysis of the mechanism and influencing factors of breakout accidents by means of investigation and tracing, it was found that mold vibration process, immersion nozzle insertion depth and mold powder performance parameters were the main factors causing breakout, and the qualitative and quantitative influence rules of three factors on breakout were studied from the perspective of mechanism and model. The results show that the lubrication state of the mold has a decisive influence on the stable production of high casting speed under the condition of uniform and strong cooling of the mold, and the appropriate vibration process is the limiting factor. After technical measures of the optimized mold vibration process(the average demoulding rate is greater than 20 mm/s), immersion insertion depth(120 mm) and mold powder are adopted(alkalinity 0.9, melting point 1 020 ℃, viscosity 0.23 Pa·s), casting speed of screw thread steel with 160 mm×160 mm section billet is finally increased from 4.1 m/min to 6 m/min, and no breakout occurred.
郑原首, 谢长川, 马桂华, 李富帅, 林真, 钱亮. 小方坯连铸6.0 m/min高拉速技术改善与生产实践[J]. 连铸, 2023, 42(4): 61-67.
ZHENG Yuanshou, XIE Changchuan, MA Guihua, LI Fushuai, LIN Zhen, QIAN Liang. Technical improvement and production practice of 6.0 m/min high casting speed for billet continuous casting. CONTINUOUS CASTING, 2023, 42(4): 61-67.
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