钢轨试件砂带磨削行为试验研究

Experimental Investigation on Grinding Behavior of Abrasive Belt for Rail Specimen

研究砂带磨削U71Mn钢轨试件的加工行为可为钢轨打磨提供基础试验数据支撑,并能探讨研发新型钢轨打磨技术关键问题.本文借助砂带试验机开展了磨削钢轨试件的加工试验,研究了砂带磨削速度、磨粒粒度等因素对材料去除效率、表面层硬度、表面粗糙度、磨削比、磨削力比的影响规律,试验表明:材料去除效率并非与砂带速度呈线性关系,较粗的磨粒与合适的砂带速度可提高材料去除效率;砂带磨削可不同程度地提高钢轨试件表层硬度,磨削速度越高、磨粒粒度越粗,对钢轨试件表面层硬化程度越明显;相比磨粒粒度而言,砂带磨削速度对表面粗糙度的影响较小;针对磨削比这一重要指标,砂带比砂轮呈现了较为明显的效益优势;磨削力比过程数据表明其变化趋势可用于表征砂带磨损.

Grinding behavior of rail specimen with material of U71Mn using abrasive belt can provide the investigated data for developing a new method of rail maintenance. Using an abrasive belt grinding apparatus, a series of experiments were performed to study the effect of grinding speed and grain size on material removal rate （MRR） , surface hardness, surface roughness, grinding ratio, grinding forces ratio. The results indicate that there is no linear relationship between MRR and grinding speed, and coarser grains and appropriate grinding speed can achieve a higher MRR. Belt grinding process can harden the ground surface of rail specimen where coarser grains and higher grinding speed can result a greater surface hardness. Surface roughness trends to be more sensitive to grain size rather than grinding speed. As for grinding ratio both in abrasive belt and grinding wheel, the former presents a clear advantage than the latter one. The function of grinding forces ratio against grinding time is a reasonable parameter to predict the wear of abrasive belt.