Sigma value, Z value, and the Cp value

Understanding of normal distribution

Z conversion

Z= Capture                                                                             24

Process capability index

Cp= Capture22

Sigma value Z value Cp value DMPO
1 0.33 -
2 0.67 308.537
3 1.00 66.807
4 1.33 6.210
5 1.67 233
6 2.00 3.4

In the short term: 6σ
In the long term: 4.5σ

DMPO: Defects per million opportunities =Value of normal distribution-1.5(One side)

Methods for Productivity Improvement (Example)




Author: Phan Nguyen

Note: The above article reprinted at the website or other media sources not specify the source is copyright infringement

Older articles



Definition: Carburizing increases the surface hardness of low carbon steel or...

Methods for determining the specifications of gears

Methods for determining the specifications of gears

The Helix angle is what differs helical gears from spur gears and it is...

Sign up to download the profile

Complete your information in the form below

You did not use the site, Click here to remain logged. Timeout: 60 second