1 Process and Measurement System Capability Analysis Chapter 7

2 Process Capability Natural tolerance limits are defined as follows:

3 Process may have good potential capability Reasons for Poor Process Capability

4 Data collection steps:

5 Example 7-1, Glass Container Data

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9 Practical interpretation – relationship of PCR to the proportion of the tolerance interval used by the process: For the hard bake process:

10 One-Sided PCR

11 Interpretation of the PCR

12 Violation of these assumptions can lead to big trouble in using the data in Table 7-2. Assumptions for Interpretation of Numbers in Table 7-2

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14 C p does not take process centering into account It is a measure of potential capability, not actual capability

15 A Measure of Actual Capability

16 Specifications not needed to estimate parameters and establish stability

17 Since LSL = 200

18 Linear Combinations

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