带锯条切削工作区应力分布研究

Investigation of Stress Distribution in Bandsaw Blade Working Area

为了分析带锯条的"切斜"失效形式,综合考虑了切削力、进给力、张紧力以及带锯条自身刀弯,建立了带锯条在切削工件区域的简化受力模型,使用数值计算模拟方法得到了带锯条各处内部应力的分布及变化趋势.结果表明,在较大的工件尺寸、切削力、进给力以及不足的张紧力和带锯条宽度的情况下,带锯条齿部处于受压状态,此时靠近齿部的带锯条基体发生弯曲形变,使得切削不再沿垂直方向进给而导致"切斜"失效发生.从验证实验来看,在同样切斜失效标准下,带锯条张紧力从130 MPa增加到190 MPa,锯切刀数增加了177%;带锯条宽度从27mm增大到34mm,锯切刀数增加了50%;工件尺寸从80mm增大到240mm后,锯切面积减少了83%.

By considering the cutting and feed force,tension and band camber,a simplified force analysis mode was set up to investigate the failure pattern of bandsaw blade crooked cutting.The stress distribution and its variation trends of bandsaw blade were obtained through numerical simulation.The result shows that the stress in the tooth side is more likely to be pushed for the situation with larger workpiece,cutting force,insufficient tension and band width.Thus,the bandsaw blade is bent near the teeth tip,and then crooked cutting happens.Under the same failure standard and cutting parameters,when the tension of band increases from 130 MPa to 190 MPa,the cutting pieces were added by 177%.Changing the 27 mm bandsaw blade to 34 mm leads to nearly 50% more cutting pieces,but it is dropped by 83% when increasing the width of the workpiece from 80 mm to 240 mm.