Research on Profile Curve of Rectangular Billets in Continuous Casting Based on Solidification and Shrinkage Characteristics

doi:10.3901/JME.2022.21.285

Abstract

Abstract: To improve the problems in traditional continuous casting mold, such as low efficiency, slow speed and defective on the surface and shape of the billet, a profile curve is designed and manufactured in continuous casting mold, which is efficient, speedy and quality (ESQ). Based on the characteristics of heat transfer and solidified shrinkage in rectangular billets mold, a geometric model of profile curve in copper mold tubes is developed. Moreover, the calculation formula about profile curve and taper curve are solved. According to the model, which is the composition of heat transfer shrinkage in continuous casting, the original model and calculation formula are modified in high-carbon steel of large rectangular billets. The results optimized are compared with traditional profile curve. Based on Matlab/GUI, the output system for profile curve in copper mold tubes is obtained with the secondary development. The copper mold tubes and mould, applied for 230 mm×170 mm U71Mn steel in continuous casting, are designed and processed for the existing steel mill. If the other continuous casting conditions remains basically, the speed of existing continuous casting machine will increase from 1.1 m/min to 1.6-1.7 m/min. The result shows that the surface quality of continuous casting billets is similar to the original and no distortion, which verifies rationality and correctness of the model calculation. Compared with the profile curve in traditional continuous casting mold, new profile curve improves heat transfer efficiency in mold and ensures processing quality of billets, which provides better technical support for increasing number of billets.

Key words: continuous casting mold, profile curve of rectangular billets, solidification and shrinkage, U71Mn high-carbon steel

CLC Number:

TG156

ZHANG Tianze, WEI Zhaocheng, WANG Minjie. Research on Profile Curve of Rectangular Billets in Continuous Casting Based on Solidification and Shrinkage Characteristics[J]. Journal of Mechanical Engineering, 2022, 58(21): 285-296.

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