MTBF certification refers to the certification of the mean time between failures of the product. The full English name is "Mean Time Between Failure". In fact, MTBF refers to the MTBF test report, which is a report on product reliability prediction. MTBF is a measure of the reliability of a product (especially electrical products). The unit is "hours". It reflects the time quality of the product and reflects the ability of the product to maintain its function within the specified time. Specifically, it refers to the average working time between two adjacent failures, also known as the average interval between failures. In a nutshell, the product with fewer failures means high reliability. The ratio of the total number of product failures to the total number of life units is called the "failure rate" (Failure rate). It only applies to repairable products. At the same time, it is also stipulated that the ratio of the cumulative working time of the product to the number of failures in the total use phase is MTBF. Generally, the MTBF of disk array products cannot be less than 50,000 hours.
7 (Reliability Analysis Center of the US Department of Defense and Rome Laboratory proposed and became the industry standard, specifically for military products), GJB/Z299B (Chinese military standard) and Bellcore (AT&T Bell Laboratory proposed and became the industry standard of MTBF for civilian products ).
The main consideration in the MTBF calculation is the failure rate of each component in the product. However, due to the large difference in the failure rate of devices under different environments and different use conditions, these factors must be considered when calculating the reliability index. These factors can hardly be calculated manually, but with the help of software such as MTBFcal and its huge parameter library, the MTBF value can be easily obtained. If a factory that works three shifts a day requires 24 hours of continuous operation and a failure rate P(t)=99% or more, the MTBF of the machine tool must be greater than 4,500 hours. MTBF5000 hours requires higher and more complicated production lines composed of different numbers of CNC machine tools. We only discuss a single machine tool here:
If the failure rate ratio of the host computer to the CNC system is 10:1 (the reliability of the CNC system is an order of magnitude higher than that of the host computer), the MTBF of the CNC system will be greater than 50,000 hours, and the CNC device, spindle, and drive part will be included. The MTBF of the main part must be greater than 100,000 hours.
MTBF is not detected in actual operation, it is converted through the national standard detection algorithm. For example, Lenovo Yangtian’s 60,000-hour MTBF is achieved by sending 192 Lenovo Yangtian computers for inspection. During a 40-day experiment period, a combination of voltage, temperature, and humidity alternating will be applied to the product under test at a specific frequency. According to the corresponding relationship between the reliability and time characteristics of electronic products, the experimental results are converted using standard data models. Similarly, Tongfang’s 100,000-hour MTBF over E350 is calculated by 400 computers and 18 days of testing results.
Telcordia SR 232
National Military Standard GJB/Z 299B