PPAP (Production part approval process)
Production part
approval process is a valuable tool that develops confidence in the component
manufacturers and their suppliers. PPAP is the risk identification process. PPAP
ensures better communication between supplier and manufacturer about the
product.
1. PPAP is the outcome of APQP.
2. PPAP is the fourth stage from APQP
(Advanced product quality planning).
3. PPAP ensures to the supplier that the
product is manufactured without any defect in the controlled production process.
4. In the automotive industry, PPAP is the
document from AIAG (Automotive Industry Action Group).
What is
PPAP?
1. It is an approval process for the new or
revised parts produced from new production methods.
2. PPAP consist of eighteen elements needed
for approval.
3.PPAP consist of five submission levels.
4. Also, it is a tool that develops the
confidence in the manufacturer and the supplier about the product being
produced and supplied by the manufacturer to his supplier.
Why PPAP?
1. PPAP verifies the fact that the
manufacturer understands all the design requirements and process developed and he is capable and proven to produce the part as per guidelines by his supplier.
2.PPAP process is only required when there
is a change in the process. Also, during machining the new parts the same
process is required.
3.During PPAP, a discussion is done with
the customer about each parameter being machined. In case, the manufacturer is
unable to achieve the specified dimension in the samples, he should inform
about it to the customer and if required, he should appeal for more dimensional
tolerance to the customer.
Documents
needed for PPAP: -
1. Design records.
2. Engineering change documents.
3. Customer engineering drawing approval.
4. DFMEA/PFMEA (Design failure mode effect
analysis/ Process failure mode effect analysis)
5. Part feasibility report.
6. Process flow diagram.
7. Control Plan.
8. Measurement system analysis (Report).
9. Material Test report.
10. SPC report.
11. Dimensional results.
12. Third-party test report.
13. List of checking instruments.
14. PSW (Part submission warrant).
15. Product samples.
16. Master sample.
17. Customer-specific requirement.
18. Process drawings.
PPAP submission levels
1. Part submission warrant (PSW) submitted
to customer.
2. PSW with product samples and limited
supported data.
3. PSW with product samples and complete
supporting data.
4. PSW with other requirements from the
customer.
5. PSW with product samples and complete
supporting data.
Elements
of PPAP
1. Design records: - It shall include the
copies of customer and suppliers’ drawings with revision levels. It should also
include purchase order and material composition information.
2. Engineering change: - PPAP is required for a change in product and documentation approving change must be included in
PPAP. This copy is an Engineering Change Notice (ECN).
3. Customer drawing approval: - Here the
trial is done at customers premises with production parts from the supplier.
Here, all the evidence must be provided with the documentation.
4. FMEA: - Here the total modes of failure
are examined with their possible effects. FMEA is a live document. Risk
priority number (RPN) for every possible mode is calculated in FMEA stage.
5. Part feasibility report: - At this
stage, engineering drawing is numbered as per the dimension. And each dimension
parameter is cross-checked for its machining feasibility.
6. Process flow diagram: - It outlines the
entire process of the product from start to end.
7. Control Plan: -It is an output of PFMEA.
It includes the list of all the dimensions, inspection methods and special
characteristics required while machining to deliver the customer quality
requirements.
8. Measurement system analysis: - It
includes Gauge repeatability and reproducibility. Gauge R and R should be
below 10%. Study of measuring equipment is done in MSA.
9. Material Test report: - It should
include the documents about the properties of material ex. Mechanical/ Chemical
properties, Microstructure etc.
10. SPC: - Initial process study about
Statistical process control is done on special characteristics. Here, the
process variation is been checked with the 32nos or 50nos of samples reading and Cp and Cpk
values are been calculated.
11. Dimensional results: - Dimensional
layout of sample parts are prepared at this stage and every dimension is
measured after machining of samples.
12. Third-party test report: - Third-party
material test report is conducted at this stage. The third-party should be NABL
accredited.
13. List of checking instruments: List of
gauges required during machining is finalized here.
14. PSW (Part submission warrant): - It is
PPAP summery. It includes the reason for submission, level of documents
submitted to the customer, supplier authorization signature, declaration of
part confirmation. PSW is not required unless the customer specifies it.
15. Product samples: - Samples after
machining are sent to the customer and they are either stored at the customer’s
end or supplier’s end.
16. Master sample: - It is a final sample
product. It is used for the training for operators and long-run production
periods.
17. Customer-specific requirement: -At this
stage, specific customer requirement is noted in PPAP. If it is not provided by
the customer, do not fill it.
18. Process drawings: - After the process is
defined, its drawing is been drawn on any 2D/3D software.
©
Kaushik