How to calculate the first pass rate?

One-time pass rate = (pass rate/total investment) * 100%.

One-time pass rate of products = number of pieces entering the process-(rework+repair+return)/number of pieces in the process * 100%.

One-time pass rate is the parameter of the product from the first process to the last process. It can understand the ability of products to achieve finished products in each process in the production process, and it is a parameter reflecting the quality control ability of enterprises and the ability of enterprises to meet customer product requirements. The higher the yield, the stronger the ability.

One-time pass rate is an index to measure the quality level of production line, which is used to describe a certain situation of production quality, work quality or test quality. Specifically, it refers to the number of good products that passed all tests in the first process among 65,438+000 sets of materials put into the production line. Therefore, products that pass the test after rework or maintenance of the production line will not be included in the calculation of the first pass rate.

What is the difference between the first pass yield and the traditional measurement method?

1. Traditionally, the yield of the whole process is measured by the first pass rate of the final stage inspection. The difference between the two is that:

A, similar to the pass rate and the first pass rate, the first pass rate can better reflect the quality of the process than the final pass rate.

B, when the final stage of inspection of a qualified rate can't reflect the quality of the previous work, a qualified rate can.

C, a pass rate can provide leaders with more correct information.

2. The pass rate can reflect the complexity of the product. The first pass rate can not only reflect the complexity of products, but also reflect the complexity of working procedures. As can be seen from the calculation formula. If the number of jobs in the process is reduced, the one-time pass rate can be improved. However, traditional measurement methods cannot reflect it.

3. Indicators such as the passing rate of six-horse management, DPU value, DPO value, DPMO value and horse-horse value are applicable to both quantitative data and counting data. Because the defects of six sigma management are directly measured according to customer requirements, which is different from the traditional measurement method. Firstly, the process capability is determined, and then the process capability indexes CP and Cpk are calculated to reflect that the process capability meets the customer's requirements. Not applicable to counting data.

4. The traditional measurement method is only the result of the measurement process, and it is to measure the past; Pass rate and sigma value can measure the ability of the process, thus giving a probability statistic value. If the conditions of the future process have not changed substantially, these data can be used to predict the future results of the process.