L70粮食漏斗车空车位加速缓解作用不良的原因分析

Analysis of Poor Accelerated Release in Empty Cargo of L70-type Grain Hopper Freight Train

120阀加速缓解作用影响列车的缓解波速,某厂装用120阀的L70型车在试制中发生多起空车位时的加速缓解作用不良现象。从120阀作用原理出发,结合L70型车整车空气制动系统的配置,通过试验对该型车加速缓解作用不良原因进行分析,认为制动系统下游管路的容积增大及大容积降压风缸分流作用显著,造成制动缸压力变低后缓解时未能形成足够的背压打开加速缓解阀逆流通路,从而出现空车位加速缓解作用不良的现象。

Accelerated release of 120 type valve has direct influence on train release velocity. Hundreds of poor accelerated alleviation phenomenon has occurred in Lr0-type grain hopper freight train with 120 type valves. In this paper, starting from the action principle of 120-type valve and combining with the configuration of air brake system for 1.70 type train, we analyze the reason of the poor accelerated release in L70 type train. It is considered that the volume of the downstream pipeline of the brake system increases and a large volume pressure reducing cylinder shunting effect markedly, resulting the pressure in brake cylinder becomes lower after remission, and thus has not formed enough hack pressure to relief the valve reflux pathway, which led to the poor accelerated release phenomenon.