指数型寿命分布产品无故障试验数据分析评估方法

Evaluation Method of Failure Free Test Data for Exponential Life Distribution Products

武器装载可靠度试验经常产生无故障试验数据,利用指数分布的无记忆性,通常认为同类型的n个产品的无故障试验时间等同于同一产品无故障工作了n个产品试验时间的总和。在工程应用中,这种方法存在局限性。文中利用浴盆曲线解释了不能完全采用这种方法进行计算的原因,即在装载总时间达到进入损耗失效条件的时候,该方法存在错误。针对这一关键问题,提出了装载可靠度计算的修正方法,给出了置信下限分析,结合算例验证了该方法的可行性。

The reliability test of weapon loading often produces failure free test data.By making use of the memorylessof exponential distribution,it is generally considered that the failure free test time of n same-type products is equal to thetotal test time of n products for one product to work without failure.In engineering applications,however,this methodhas limitation.This paper explains the reason why this method cannot be fully used for calculation by making use of thebathtub curve,that is,there is a mistake when the total load time is up to the failure condition.To solve this problem,amodified method for calculating the reliability of loading is proposed,and the lower confidence bound is given.Thefeasibility of the proposed method is verified by an example.