一种计算热轧钢筋成品辊轧制时前滑值的经验公式
2016-08-25魏书斌
魏书斌
(安阳钢铁股份有限公司)
一种计算热轧钢筋成品辊轧制时前滑值的经验公式
魏书斌
(安阳钢铁股份有限公司)
通常热轧带肋钢筋轧制时,因成品需充填横肋和纵肋,使之金属流动过程复杂,造成影响前滑值因素增多,故计算其前滑值困难。充分利用钢筋成品轧制时,前滑值便于实测的有利条件,在对大量数据进行统计分析的基础上,归纳总结出一种经验公式,以便计算出棒材机组钢筋成品轧辊轧槽的横肋个数,从而准确确定出钢筋横肋间距,使得钢筋横断面金属量得到合理分配,促进了钢筋生产质量的稳定。
前滑值热轧带肋钢筋横肋间距成品孔
ABSRACTUsually during hot rolled ribbed steel bar rolling, because the finished product should be filled with transverse ribs and longitudinal ribs, the metal flow process is complicated, and the factors of affecting the forward slide value are increased, so it is difficult to calculate the forward slip value. An empirical formula to calculate the number of transverse rib of the steel bar finished roll mill is summarized based on a large number of statistical analysis through making full use of favorable conditions that forward slip value is easy to measure during finished product rolling. Therefore, rib spacing can be accurately determined, the steel cross-section of the metal is reasonably distributed, and promote the quality of steel production stability.
0 前言
钢筋混凝土用热轧带肋钢筋其表面要求有均匀分布的横肋。国标1499规定,带肋钢筋横肋公称间距不得大于钢筋公称直径的0.7倍[1],同时,对钢筋横肋间距允许偏差也有明确规定。通常热轧带肋钢筋成品孔型设计时,为保证热轧钢筋横肋间距满足国家标准要求,成品轧槽横肋个数采用下式来计算:
(1)
式中:n——横肋个数,个;
D——轧辊工作直径,mm;
S——前滑值;
L——横肋间距,mm;
ΔL——横肋间距正偏差。
从式(1)可知,要准确计算横肋个数,必须知道前滑值。影响前滑值的因素很多,有压下率、轧件厚度、轧件宽度、轧辊直径、磨擦系数、张力等[2]。前滑值的计算很不准确。理论上前滑值的计算公式,是在平辊轧制,忽略宽展的基础上推导出来的,在宽展较小的轧制方法方法中,如板带轧制,具有较大的适应性,在型钢轧制中,由于孔型存在侧壁,即产生强迫宽展或限制宽展,前滑值的理论计算存在较大难度。……
