无缝钢管轧制力的计算方法研究

Research on calculation method of rolling force of seamless steel pipe

无缝钢管制造过程中的轧制力是一个重要工艺参数,通常基于平板轧制经验公式建立计算模型。本文基于钢管的轧制机理,建立了轧辊直径、轧制孔型、毛管尺寸、轧制压下量、轧辊与毛管的接触角、轧制速度、轧制温度等参数与轧制力的关系,采用离散化方法将轧辊与毛管的轧制接触区按照减径区和减壁区分别离散成若干个单元,并将接触区的变形速度也按相应的单元进行离散化处理。采用热模拟实验确定材料的应变速度和温度与屈服应力的关系,计算接触区各单元的屈服应力和轧制压力以及机架方向的轧制力,通过各单元的轧制力叠加获得总的轧制力和管体的压溃力。通过这种方法获得的轧制力远比传统计算方法获得的轧制力准确,能够满足轧制工艺控制的要求。

The rolling force in the manufacturing process of seamless steel pipe is an important process parameter, and the calculation model is usually established based on the empirical formula of plate rolling. Based on the rolling mechanism of steel pipe, the relationship between roll diameter, rolling pass, capillary size, rolling reduction, contact angle between roll and capillary, rolling speed, rolling temperature and rolling force is established in this paper. The rolling contact zone between roll and capillary is discretized into several units according to the reducing diameter zone and the wall reduction zone, and the deformation speed of the contact zone is also discretized according to the corresponding element. The relationship between the strain velocity and temperature of the material and the yield stress is determined by thermal simulation experiment. The yield stress and rolling pressure of each element in the contact zone and the rolling force in the frame direction are calculated. The total rolling force and the crushing force of the pipe body are obtained by the superposition of the rolling forces of each unit. The rolling force obtained by this method is much more accurate than that obtained by the traditional calculation method, and can meet the requirements of rolling process control.