高寒雨雪气候下高速动车组盘片摩擦副摩擦性能

Friction Performance of Brake Disks and Blocks for High-Speed EMU Trains in Cold,Rainy,and Snowy Weather

为了提高高速动车组在低温潮湿气候条件下的运行安全性,模拟-15~20℃雨雪环境,试验研究了高速列车制动系统的摩擦磨损性能以及制动盘表面划伤、制动力衰退等现象产生的原因.研究结果表明:在高寒雨雪环境下,制动副摩擦因数随着制动压力增加而增大;外来硬质点对摩擦因数的影响与制动初速度有关,当制动初速度低于160 km/h时,摩擦因数随着制动初速度提高而增大,当制动初速度大于等于160 km/h时影响不明显;夹钳被冰雪所覆盖冻结,影响夹钳缓解复位,使制动盘和闸片间隙变小,制动盘与闸片易产生接触碰撞,夹在盘片之间外来硬质点不易排出,加剧制动盘表面划伤;采用每隔7 min进行间隙式1 min低压力连续制动,可以清除制动盘表面冰膜,并能防止整个夹钳被冰雪所覆盖而冻结.

In order to improve the safety of high-speed train operation in cold weather, the braking performance of a high-speed EMU train in temperature range from -15 °C to 20 °C in rain and snowy conditions was simulated and the causes of decline in braking force and scratching of the brake disk surface were investigated. The results showed that the average friction coefficient increased with increasing braking force. The effect of external hard particles on the friction coefficient varied with the braking speed. When the speed was less than 160 k m / h , the friction coefficient increased with increasing speed. When the speed was more than 160 km/h, the external hard particles did not have an obvious effect on the friction coefficient. It was also found that the decline in transmission efficiency of the clamp in severely low temperatures and wet conditions was due to the clamp being covered with snow and becoming difficult to reset, which in turn reduced the clearance of the brake disk and brakeblocks. In such a situation, external hard particles or contact between the brake block and disc wouldresult in scratches on the brake disk surface. The research showed that braking for 1 min after every 7 min interval could remove the ice on the brake disk surface and prevent the clamp from being frozen in ice.