我国主型12号道岔动力学特性分析

对我国主型12号道岔进行动力学测试发现,空车通过道岔侧向时脱轨系数超过限值要求。为此实测钢轨型面,对其轮轨接触特征进行分析,发现磨耗后的道岔下股钢轨轨顶呈明显扁平状,轮轨接触点向车轮踏面外侧转移,使得轮径差减小;上股钢轨轨肩磨耗明显,形成两点接触,减小了导向力矩;双重因素作用下降低了道岔侧向通过性能。优化轮轨关系是改善道岔区动力学性能的有效途径,结合道岔区实际运营状态,提出一种适用于道岔区的钢轨打磨廓形,优化了道岔区轮轨接触参数。动力学计算结果表明:钢轨打磨廓形可有效改善轮轨相互作用特性,明显降低车辆通过道岔侧向时的动力学指标,提高道岔区安全运营裕量。

Analysis of Dynamic Characteristics of No.12 Turnout in China

The dynamic test of No. 12 turnout which was used in China show ed that the unloaded vehicle derailment coeff icient exceeded the limit when the vehicle passed through turnout branch line.To study the case,the rail prof iles were measured to analyze the wheel/rail contact features.It was found that the railhead prof ile of turnout low rail was flatten after wear.The contact point shifted tow ard outside of the wheel tread,which reduced the wheel diameter difference.Two points contact occurred because of the significant side wear of high rail,and the steering moment was decreased. The dynamic performance in turnout branch line deteriorated due to the adverse contact characteristics.The dynamic performance can be improved by optimization of wheel/rail relationship. Based on the real turnout status,a rail grinding prof ile suitable for the turnout area was proposed,which optimized he wheel/rail contact parameters in the turnout area. The dynamic calculation results show that the rail grinding prof ile can improve wheel/rail interaction,reduce the dynamic indexes of vehicle when passing through turnout branch line,and increase operation safety margin in turnout area.