T
tsider
Hello everyone the forum is great! Anyway I am new here and excuse me for my bad English in advance. I am trying to calculate the sigma level of defects for a manufacturing process for an essay.
The numbers are based on a real factory that produces let's say something like 100 different product lines. I don't have any ASL/LSL. I checked the overall defect rate distribution is normal, I didn't check per line because they are so many of them ;p)
First, I weighted the lines according to what proportion contribute for the general production (like Pareto). The final, overall weighted value of defects was something like 20%.
Then, I tried to convert it to DPMO. It's a compound product and since 2 main controls are made in order to considered good (optical/dimensional), I used 2 at the fraction. However, my DPMO number is something like 15.000, and thus shows my process much better than it really is.
So is it better to rely on the dpu=20% instead? Is there a way to convert it into a sigma level?
Any advice or any comment on the procedure I followed is more than welcome and needed.
The numbers are based on a real factory that produces let's say something like 100 different product lines. I don't have any ASL/LSL. I checked the overall defect rate distribution is normal, I didn't check per line because they are so many of them ;p)
First, I weighted the lines according to what proportion contribute for the general production (like Pareto). The final, overall weighted value of defects was something like 20%.
Then, I tried to convert it to DPMO. It's a compound product and since 2 main controls are made in order to considered good (optical/dimensional), I used 2 at the fraction. However, my DPMO number is something like 15.000, and thus shows my process much better than it really is.
So is it better to rely on the dpu=20% instead? Is there a way to convert it into a sigma level?
Any advice or any comment on the procedure I followed is more than welcome and needed.
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