St. Paul, Minn. “Now, it is still OEMs, but smaller ones are asking for it. And at the same time, the large OEMs are adding additional requirements.” According to Hartigan, APQP is
an integrated system for anticipating possible modes of failure, eliminating them in the design and production planning phases, demonstrating com- pliance with critical factors, assessing accuracy of measuring equipment, assuring consistency, and documenting and planning for success. Te PPAP, as a component of APQP, includes fail- ure mode element analysis (FMEA) and a control plan. Trough record- keeping, PPAPs are used to prove how the supplier will produce the casting and that the process used will result in a quality part. “Te PPAP is a group of reports
that is documenting the process and providing measurements to show the part is being produced and made to the required specifications,” said Ron Helgeson, Caterpillar, Mapleton, Ill. “It is a verification you are getting the part you asked for.” PPAP recordkeeping requirements
are outlined in six sections: 1. General 2. PPAP Process Requirements 3. Customer Notification and Submission Requirements
4. Submission to Customer—Levels of Evidence
5. Part Submission Status 6. Record Retention. Te essence of the PPAP lies
in Section 2, where the control plan, FMEA and process flow are addressed. Collaboration with the
Table 1. Sample of PPAP Requirements and Responsibilities of Core Reviewers at Caterpillar AIAG PPAP Fourth Edition Requirements
2.2.1 Design record
2.2.1.1 Reporting of part material composition 2.2.1.2 Marking of polymeric parts
2.2.2 Authorized engineering change documents 2.2.3 Customer engineering approval 2.2.4 DFMEA
2.2.5 Process flow diagrams 2.2.6 PFMEA
2.2.7 Control plan
2.2.8 Measurement system analysis studies 2.2.9 Dimensional results
2.2.10 Records of material/performance test results 2.2.10.1 Material test results 2.2.10.2 Performance test results 2.2.11 Initial process studies 2.2.11.1 General
2.2.11.2 Quality indices
2.2.11.3 Acceptance criteria for initial study 2.2.11.4 Unstable process
2.2.11.5 Process with one-sided specifications or non-normal distributions 2.2.11.6 Actions to be taken when acceptance criteria not satisfied 2.2.12 Qualified laboratory documentation 2.2.13 Appearance approval report (AAR) 2.2.14 Sample production parts 2.2.15 Master sample 2.2.16 Checking aids
2.2.17 Customer-specific requirements 2.2.18 Part submission warrant 2.2.18.1 Part weight (mass)
Yes Yes Yes Yes Yes Yes
Yes Yes Yes Yes Yes
Yes Yes
Yes Yes Yes Yes Yes
customer on this section can ensure potential problem areas are identified early and avoided before the parts are ever produced.
Control and Statistics
Caterpillar is well known for its supplier development program, so it is no surprise it emphasizes collabo- ration in its PPAP planning. “We like to include the process
control engineer and the potential supplier very early in the design process to make the part as manufac- turable as we can and still address the functionality required by the design engineer,” Helgeson said. Te process control engineer assigned to a supplier at Caterpillar has most likely been to the supplier and knows the casting process. Tis is
Engineering Evaluates Yes
Quality Evaluates Yes
Yes Yes Yes
PCE Evaluates Yes
Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
September 2013 MODERN CASTING | 41
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