PPAP and First-Article
Inspection.

PPAP (Production Part Approval Process) is a standardised set of documents and samples that a supplier submits to a customer to demonstrate that the production process can consistently produce parts that meet all engineering requirements. The AIAG PPAP manual (currently 4th edition) is the primary reference. PPAP originated in the automotive sector but is now widely required by industrial OEMs and Tier-1 suppliers across sectors.

A PPAP submission says: 'We have run a production-representative batch, measured the critical dimensions, tested the material, documented the process, and the results demonstrate that we can meet your requirements in production.' The customer reviews and either approves the submission or raises concerns before production begins.

The AIAG manual defines five submission levels, determining which elements must be submitted to the customer versus retained at the supplier.

Level 1: Part submission warrant only (PSW). Appropriate for very low-risk commodities. Level 2: PSW with product samples and limited supporting data. Level 3: PSW with product samples and complete supporting data. This is the default level for most automotive and industrial programmes. Level 4: PSW and other requirements as defined by the customer. Level 5: PSW with product samples and complete supporting data — reviewed at the supplier's facility.

For new aluminium die casting and machining suppliers, Level 3 is almost always required. SAPL prepares Level 3 PPAP as standard for automotive customers.

A complete Level 3 PPAP for a cast and machined aluminium part typically includes:

Design record: The customer-approved drawing that defines the part.

Process flow diagram: Map of all production steps from incoming raw material through to dispatch.

Process FMEA: Analysis of process failure modes, effects, and controls at each production step.

Control plan: Documents the inspection and process control methods at each production step, including measurement method, sample size, and frequency.

Measurement System Analysis (MSA): Gauge R&R study demonstrating that the measurement system is capable of distinguishing good from bad parts.

Dimensional results: All characteristics measured on a sample of parts (typically 30 minimum). Results shown against drawing nominal and tolerance for every balloon.

Material performance test results: Tensile strength, hardness, and chemical composition results from production-representative parts.

Initial process studies (Cpk): Statistical capability index for all critical dimensions. Cpk ≥ 1.67 is required before full PPAP approval.

Sample production parts: Physical samples from the PPAP run, retained by the supplier and/or submitted to the customer.

Part Submission Warrant (PSW): The cover document summarising the submission, signed by an authorised representative of the supplier.

First-Article Inspection (FAI) is the dimensional and material verification of the first production-representative parts made from a new tool or process. FAI is mandatory before PPAP submission — the PPAP dimensional results are the output of the FAI.

For die cast and machined aluminium parts, the FAI typically covers: full balloon inspection of all drawing dimensions on a minimum of 30 parts from the production run, CMM measurement for critical features (bores, mating faces, position of hole patterns), hardness testing per batch, material certificate review for the alloy heat used, and review of surface finish and visual appearance.

At SAPL, all first-article inspections are conducted in-house using our CMM and calibrated gauging. Detailed inspection reports are provided for every first article and retained on file.

When a new programme is approved, SAPL's quality team prepares a PPAP timeline as part of the programme plan. Key milestones include: tool design review, T1 samples (first tool trials), T2 samples (corrected tool after T1 review), PPAP run (30–50 parts from full production process), dimensional inspection and lab testing, PPAP submission to customer, and customer approval (PSW sign-off).

Total time from tool start to PPAP approval typically runs 10–16 weeks depending on tool complexity, customer review cycle, and number of tool revision rounds.

SAPL provides PPAP documentation in English throughout. Our current QMS (ISO 9001:2015) includes FMEA, control plan, and MSA documentation. We are actively working towards IATF 16949 certification (not yet certified).