Effect of nozzle spray distance on the secondary cooling uniformity of continuous casting billet

HAN Yan-shen; ZHANG Jiang-shan; ZOU Lei-lei; ZENG Fan-zheng; GUAN Min; LIU Qing

doi:10.13374/j.issn2095-9389.2019.12.26.001

Volume 42 Issue 6

Jun. 2020

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Article Navigation > Chinese Journal of Engineering > 2020 > 42(6): 739-746

HAN Yan-shen, ZHANG Jiang-shan, ZOU Lei-lei, ZENG Fan-zheng, GUAN Min, LIU Qing. Effect of nozzle spray distance on the secondary cooling uniformity of continuous casting billet[J]. Chinese Journal of Engineering, 2020, 42(6): 739-746. doi: 10.13374/j.issn2095-9389.2019.12.26.001

Citation:

HAN Yan-shen, ZHANG Jiang-shan, ZOU Lei-lei, ZENG Fan-zheng, GUAN Min, LIU Qing. Effect of nozzle spray distance on the secondary cooling uniformity of continuous casting billet[J]. Chinese Journal of Engineering, 2020, 42(6): 739-746. doi: 10.13374/j.issn2095-9389.2019.12.26.001

Citation:

HAN Yan-shen, ZHANG Jiang-shan, ZOU Lei-lei, ZENG Fan-zheng, GUAN Min, LIU Qing. Effect of nozzle spray distance on the secondary cooling uniformity of continuous casting billet[J]. Chinese Journal of Engineering, 2020, 42(6): 739-746. doi: 10.13374/j.issn2095-9389.2019.12.26.001

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Effect of nozzle spray distance on the secondary cooling uniformity of continuous casting billet

doi: 10.13374/j.issn2095-9389.2019.12.26.001

1.
State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083, China
2.
Xiangtan Iron & Steel Co., Ltd. of Hunan Valin., Xiangtan 411101, China
3.
Jiangsu Boji Spraying Systems Co., Ltd., Yangzhou 225267, China

More Information

Corresponding author: E-mail: qliu@ustb.edu.cn
Received Date: 2019-12-26
Publish Date: 2020-06-01

Abstract

Abstract

In the secondary cooling zone of continuous casting, the cooling uniformity of the billet largely depends on water flux distribution and is closely related to crack formation. Nozzle spray distance is the main influencing factor of water flux distribution in continuous casting billet. Therefore, the investigation of the effect of nozzle spray distance on secondary cooling uniformity is of considerable importance in the design and optimization of the secondary cooling system of the billet. In the present study, the water flux distributions of the nozzles used in the secondary cooling zone of continuous casting of the billet were measured under different spray distances. A heat transfer and solidification model was established to analyze the thermal behavior of 82B steel billet. The model specifically considered the distribution of secondary cooling water along the transverse direction and was calibrated via comparing the measured and simulated surface temperatures. The effect of nozzle spray distance on the secondary cooling uniformity of the billet was investigated using the model. Results show that the increase in nozzle spray distance helps to improve the uniformity of secondary cooling water along the transverse direction, resulting in the decreased transverse uniformity and increased longitudinal uniformity of surface temperature. These effects are beneficial for the internal cracks but harmful for the corner cracks of the billet. Increasing the nozzle spray distance in the first segment of the secondary cooling zone and decreasing the nozzle spray distance in the second segment of the secondary cooling zone can decrease the maximum reheating rate and increase the corner temperature, thereby achieving the purpose of simultaneously improving the internal and corner cracks of the billet. On this basis, a nozzle arrangement method, i.e., gradually increasing the nozzle spray distance along the casting direction of each segment in the secondary cooling zone was proposed. This method contributes to the improvement of “longitudinal–transverse” cooling uniformity of the continuous casting billet.
- continuous casting billet,
- nozzle spray distance,
- water flux distribution,
- heat transfer and solidification,
- secondary cooling uniformity

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References(25)

References

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