The reliability evaluation indices of bus arrangement systems are availability, unavailability, failure frequency, mean time between failure, mean time to repair, failure rate and repair rate. 文中计算的电气主接线系统的可靠性指标是:可用度,不可用度,故障频率,平均相邻故障间隔时间,平均修理时间,故障率,修复率。
To satisfy these requirements, either MTBF ( Mean Time between Failures) is lengthened or MTTR ( Mean Time to Repair) is shortened. 要满足这一要求,一方面延长平均无故障时间MTBF,另一方面缩短排除故障修理时间MTTR。
The mean time between failure ( MTBF) is 449 hours, and the mean time to repair ( MTTR) is 22. 1 hours. ln its subsystems, the MTBF of tool post is smallest and that of electric system is biggest; 平均无故障时间MTBF为449h.平均修复时间MTTR为22.1h.各子系统中,方刀架的可靠性最好,电器系统的可靠性最差;
Finally obtain the mean time between failures ( MTBF), mean time of repair failures ( MTTF), inherent availability ( A) as well as reliability index such as reliability and failure rate function according to the distribution model. 最后根据分布模型计算得到该加工中心的故障间隔时间(MTBF)、平均维修时间(MTTF)、固有可用度A以及可靠度和失效率函数等可靠性指标。