To understand the acceptance values of the process capability, the first thing to look at is customer-specific requirements. Apart from this, according to AIAG PPAP revision, 4 manual published by Ford, GM, DaimlerChrysler on 1st of June 2016, the acceptance criteria were determined as follows.
Process capability is > 1,67: The process currently the acceptance criteria.
1,33 ≤ Process Capability ≤ 1,67: The process may be acceptable. Contact the authorized customer representative for a review of the study results.
Process Capability is < 1,33: The process does not currently meet the acceptance criteria. Contact the authorized customer representative for a review study results.
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