The emergency device is widely used in welding reinforcement points or injury site in the temporary rescue tools in railway departments and rail, an emergency on the rail fracture, in order to train the rail can be an emergency device directly installed in parts of the corresponding types of rail fracture. You can make the train at a lower safe speed through the normal. First aid is divided into 43 types, type 50, type 60, type 75, respectively, corresponding to the use of rail models.