湖南铁路科技职业技术学院毕业设计（论文）120阀常见故障分析与处理目录前言.....................................................................3一、120阀的构造........................................................41.中间体.............................................................42.主阀...............................................................53.缓解阀.............................................................54.紧急阀.............................................................6二、120阀的作用........................................................71.充气缓解位.........................................................71.1初充气...........................................................71.2再充气和缓解....................................................82.减速充气缓解位....................................................83.常用制动位.........................................................84.制动保压位........................................................105.紧急制动位........................................................106.缓解阀的作用......................................................11三、120阀常见故障与分析...............................................121.常见故障分析......................................................121.1主阀.............................................................121.2紧急阀..........................................................131.3缓解阀..........................................................151.4列车中120阀缓解慢（抱闸）现象的分析..........................152.其他原因分析......................................................163.解决措施和建议...................................................17四、单车试验120阀的故障判断和处理...................................171.充气时主阀排风口大排风...........................................172.不制动或制动灵敏度差.............................................173.制动后不缓解或缓解过慢...........................................184.制动后保压时发生再制动...........................................185.制动后保压时自然缓解.............................................18湖南铁路科技职业技术学院毕业设计（论文）120阀常见故障分析与处理6.紧急制动不灵敏或不起紧急制动作用................................19