由于高速列车轴承造价昂贵、精度和可靠性要求极高等问题,在进行可靠性寿命试验时,只能做极小样本、短时间内的定时截尾寿命试验。为有效的对其进行可靠性评估,采用不完全混合Beta分布作为轴承累积失效概率的先验分布,结合多层Bayes可靠性评估方法,求解出极小样本无失效情况下的高速列车轴承可靠性数学模型。通过计算,在给定的可靠性指标要求下,所得结论符合实际情况,且采用不完全混合Beta分布作为先验信息的评估方法较传统Bayes方法具有明显的合理性。
In the view of the problem of cost,accuracy and reliability requirements of the high-speed train bearing, a minimum sample censored time test can only be performed in a short time during the reliability life test. In this case,the incomplete mixed Beta distribution is adopted as a prior distribution of the bearing cumulative failure probability to evaluate its reliability effectively. According to the hierarchical bayesian reliability assessment method,the reliability mathematical model is obtained for the high-speed train bearing in the condition of minimum sample and zero-failure. The calculating result is in line with the actual situation at the request of a given reliability index. And the assessment method considering the incomplete mixed Beta distribution is more reasonable than the traditional Bayesian method.