Calculation of Standard deviation, Cp & Cpk in SPC
Foe below result achieved see calculation of how Mean Value, Standard deviation, Cp & Cpk is calculated in standard SAP
See below result of Mean Value, Standard deviation, Cp & Cpk is calculated in standard SAP
From above screen I have taken below reading
1. Calculation of Mean value
So Mean Value, = (Sum of Recorded Result) / No. of Record
Mean Value = 38.667
The mean (38.667) is closer to one of them than to the other, leading to a Cpk factor (0.17) that is lower than the Cp value (0.22). This implies that the LSL is more difficult to achieve than the USL. Non-conformities exist at both ends of the histogram.
good example on calculating Cp, CpK.
Good one. What master data settings are maintained to calculate mean, Cp and Cpk?
Thanks & Regards,
Most of it is statistics knowledge.
How do you display Process Capability window for given results?
How do to select USL and LSL limits?
I have measured results of 30 samples Re is 3.43, 3.27 ,3.19, 3.17,3.17, 3.19, 3.19, 3.24, 3.1, 3.12 ,3.25, 3.2, 3.35, 3.2, 3.2, 3.22, 3.23, 3.18, 3.19, 3.31, 3.18, 3.08, 3.18, 3.17, 3.23, 3.19, 3.25, 3.26, 3.23, 3.18
mean = 3.2117, STD = 0.07
Company datasheet provided for Re is 3.08 and production tolerances +/- is 7.50%
to find Cpk how do I calculate USL and LSL values?
Actually, which is the target value?