分析了管网失效的早期失效期、偶然故障期和耗损失效期的特点，探讨了偶然故障期管网系统的可靠性评价方法。
The characteristics of earlier failure period , random failure period and loss failure period of gas network are analyzed , and the method of reliability assessment is investigated for gas network in random failure period .
耗损失效期