V-TEK PT-55, User Manual

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D291308.7M.fm Main Screen Details
Chapter 3: Operation 35
Peel Test Statistics
The bar along the bottom of the graph displays a number of values..
Min
Minimum peel force from a peel force test.
Max
Maximum peel force from a peel force test.
Mean
The average peel force from a peel force test.
Range
The minimum peel force test subtracted from the maximum peel force test.
StDev (Sample Standard Deviation)
Measurement of how much the data is scattered. The formula for this calculation is:
Cp (Process Capability)
An indicator of process capability.
The formula for this calculation is: Cp = (UCL - LCL) / 6s)
Cpk (Process Capability Index)
Adjustment of Cp for the effect of non-centered distribution.
The formula for this calculation is: Cpk = Min [ ( x ̅ - LCL) / (3s) ; (UCL - x ̅ ) / (3s) ]
Note : Cpk measures how close the peel force is to the target and how consistent the average
performance is.
Figure 3.12