The videos below describe the “how to” of process capability in SPC for Excel. These videos illustrate how you can quickly turn your data into charts showing how well your process meets your customer specifications using SPC for Excel. This page contains:
PROCESS CAPABILITY SNAPSHOT
The Process Capability SnapShot gives a picture of your process capability in time. This technique is for normally distributed data and generates the capability chart, control charts and normal probability plot plus the process capability metrics. The video below shows how this technique is done in the SPC for Excel software.
PROCESS CAPABILITY SNAPSHOT FOR NON-NORMAL DATA
The Process Capability SnapShot for non-normally distributed data gives a picture of your process capability. This technique generates the capability chart, P-P plot and control charts plus the process capability metrics. The video below shows how this technique is done in the SPC for Excel software.
The video below shows how to make the process capability chart using SPC for Excel. The Cpk chart contains the histogram, the normal curve (based on the estimated sigma and/or the calculated standard deviation), the specifications, the nominal, as well as the process capability statistics (you have the option to determine which ones to include on the chart). There are also many options including adding the average, adding confidence limits for Cpk, adding the +/- 3 sigma lines, adding the target to generate the Cpm value, using the historical average and standard deviation, transforming the data using the Box-Cox or Johnson transformations and controlling the number of or width of the histogram classes.
NON-NORMAL PROCESS CAPABILITY
Sometimes, your data are not normally distributed. SPC for Excel software has the capability of handling non-normal process capability analysis. The data can be fit to one of 13 different distributions. The software generates the histogram with distribution curve, plots the specification limits, handles one-sided specifications and generates all the capability statistics you need for non-normal distributions.