针对有寿件工作寿命分布不确定、备件数量难预测的问题，提出了一种基于正态等效的有寿件保障方案确定方法。首先通过贝叶斯理论将有寿件的工作寿命分布等效为正态分布，进而计算其备件需求量；然后提出到寿更换概率指标用以度量部件在更换周期内的安全收益；最后通过综合权衡安全收益和经济成本确定有寿件的最佳更换周期，得到备件保障方案。在算例中，通过与仿真结果的对比表明：本文方法合理可行，精度较高。

For the problem of uncertainty of work life distribution and difficulty in predicting demands for life-limited spares, a determination method of support plan for life-limited spares is proposed based on Normal-equivalence. At first, work life of life-limited spares is equivalent to Normal distribution based on Bayesian theory in order to calculating the numbers of spares demand; Then life replacement probability is put forward to measure the safety benefits during the replacement cycle; Finally, the optimal replacement cycle is obtained by tradeoff between safety benefits and economic costs so that the support plan is also got. Compared with simulation results, the examples show that our method is reasonable and feasible and owns high precision.