Production Part Approval Process

Part Approval Process


PPAP is a series of documents gathered as a package which need a formal certification/sign-off by the supplier and approval/sign-off by the customer. The form that summarizes this package is called PSW (Part Submission Warrant). This type of submission is the most commonly used for technical moulding products.

Suppliers can be required to obtain PPAP approval whenever a new or modified component is introduced to production, or the manufacturing process is changed.

Obtaining approval requires the supplier to provide sample parts and documentary evidence showing that:

1) The client’s requirements have been understood
2) The product supplied meets those requirements
3) The process (including sub suppliers) is capable of producing conforming product
4) The production control plan and quality management system will prevent non-conforming product reaching the client or compromising the safety and reliability of finished vehicles

PPAP may be required for all components and materials incorporated in the finished product and may also be required if components are processed by external sub-contractors.

Typical documents submitted are –

  • Design Record – Including drawings and material/test specifications
  • Engineering Change Documents – Any marked and signed drawings, specifications etc., authorizing a Supplier to deviate from the design record.
  • Design FMEA (DFMEA), if Supplier is Design
  • Process Flow Diagram (PFD) – The Process Flow Diagram must follow the process from receipt of raw material to final shipment. It should also include any potential paths that a part can take in the process, including sub-contracted activities, inspection, containment, rework, and scrap.
  • Process FMEA (PFMEA) – This needs to cover all manufacturing operations from individual components to assemblies and Include all processes within the plant that can impact the manufacturing and assembly operations.
  • Pre-Launch Control Plan. The Pre-Launch Control Plan must follow the process from receipt of raw material through shipping steps.
  • Measurement System Analysis (Gauge R&R or Fixture Verification)

All gauges in the Control Plan must have a Gauge R&R study completed, even if the gauge is a hand tool, such as a micrometer.  Items are checked to see that measurement is repeatable. For example, 10 components are measured 30 times by 3 qualified people.  There needs to a less than 10% of tolerance variation for a Gauge to ‘pass’.

More complex fixtures are checked against 2D drawings or CAD models.

  • Material Certifications – Include any material certifications / material test results relating to the part and the base materials.
  • Initial Process Capability (CAP) Studies (CpK/PpK). In the initial process studies for special characteristics, the Supplier needs to demonstrate that the process is stable and in control through the use of a control chart. Normality and capability must also be demonstrated.
  • Appearance Approval Report – Any part that is colour matched, needs graining, or other appearance approval must have an appearance approval report attached to the PPAP. Master samples will need to be produced and retained
  • Part Submission Warrant. This is a summary of the documentation included in the PPAP

PPAP Submission Levels

Level 1 – Part Submission Warrant (PSW) only.
Level 2 – PSW with product samples and limited supporting data.
Level 3 – PSW with product samples and complete supporting data.
Level 4 – PSW and other requirements as defined by the customer.
Level 5 – PSW with product samples and complete supporting data available for review at the supplier’s manufacturing location.


The term ISIR (initial sample inspection report) is commonly used by German companies like VW and BMW. ISIR is like the Warrant and Inspection Report of PPAP document package.