The special spare tire can both be used temporarily when a tire is leaking or a tire blows out and also used as a normaltire.
专用备胎不仅是在轮胎漏气或者发生爆胎时临时使用，也可作为正常轮胎使用。
2
Nitrogen is the inert gases, low expansion coefficient, not easily with the environmental temperature rise for a long time, can maintain normaltire pressure, greatly reduce the flat tire.
氮气是惰性气体，膨胀系数低，不轻易随环境温度上升而上升，可较长时间维持正常胎压，大大降低爆胎几率。
3
The wear classifications are presented based on the principle of Tribology, which provide the fundamental knowledge for correctly predicting tire wear rate at normal service conditions.