2、随机振动 图6表明随机振动量值和振动时间对筛选效率的影响。量值低于4grms时的筛选不太有效,而6grms(0.04g~2/Hz)量值下筛选效果要高得多;筛选效率还随振动时间的增加而迅速提高。该图中表明,振动30分钟将可发现80％左右失效。但大多数经验表明,振动5～10分钟就能达到理想的效果。因此标准中规定试验在最敏感轴向振动5分钟。 2, random vibration Figure 6 shows the magnitude of random vibration and vibration time on the screening efficiency. Screening at less than 4grms was less effective, whereas screening at 6grms (0.04g ~ 2 / Hz) was much higher; screening efficiency also increased rapidly with increasing shaking time. The figure shows that vibration for 30 minutes will find about 80% failure. But most experience shows that the vibration of 5 to 10 minutes to achieve the desired effect. Therefore, the standard specifies the test vibration in the most sensitive axis for 5 minutes.