预应力混凝土用螺纹钢筋LF炉精炼工艺实践

PROCESS PRACTICE TO REFINE WITH LF FURNACE THE REINFORCED BAR USED FOR PRESTRESSED CONCRETE

预应力混凝土用螺纹钢筋简称精轧螺纹钢筋,因具有高强度、高精度、施工便捷而著称,结合广阔的市场前景,石横特钢决定在二炼钢开发屈服强度不低于830 MPa的PSB830级精轧螺纹钢筋。由于该钢种属于高Si低Mn钢种,且Mn/Si低(0.44～0.80),不利于脱氧合金化操作及连铸浇铸,通过对LF炉精炼工艺的实践,不仅实现了化学成分的精准控制,钢材批次之间性能差异控制在30 MPa以内,而且钢水纯净度达到了目标要求,有效保证了连铸浇铸质量。

Reinforced bar used for pre-stressed concrete is simply called as finish-rolling reinforced bar.It has broad market prospect with high strength,high precision and convenient to use.We decided to develop finish-rolling reinforced bar of PSB830 class with yield strength not lower than 830 MPa in the No.2 Steelworks.This steel grade belongs to high-Si and low-Mn grade and its Mn/Si is low（0.44 to 0.80）,difficulty for deoxidation alloying operation and continuous casting.During the practice of refining process in LF furnace,it is but realized the precision control of chemical composition： performance difference between various patches being controlled within 30 MPa,also reached the target of purity degree and effectively guaranteed the quality of continuous casting.