MTR Heat Number Mismatch at Final Release
At final release, the inspector reviews the documentation package for 20 forged valve bodies. The material test reports list heat number H-4471 for all 20 forgings, but the permanent markings on three forgings read H-4471A. The supplier's certificate of conformance states that all material requirements were met and that impact testing was performed. The MTR includes tensile and chemical results but no impact test results. The supplier says the A suffix is an internal forging-lot suffix and that impact testing was done on a separate test coupon not shown on the MTR. The customer requires full traceability from raw material to finished part.
1. Can the inspector release the package as submitted? Identify the traceability and documentation gaps.
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The package should not be released as submitted. The heat-number mismatch breaks the traceability chain: H-4471A markings must be reconciled to the MTR for H-4471, or the correct MTR must be provided. The certificate of conformance asserts impact testing, but the MTR does not report impact results; if impact testing is a specified requirement, the results must be traceable to the tested lot and to the parts. A separate coupon is acceptable only if the applicable specification and the supplier's procedure allow it and the coupon is traceable to the same heat and processing lot. The inspector should require a corrected documentation package before release.
2. What verification steps should the supplier complete to close the heat-number and impact-test gaps?
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The supplier should provide a written reconciliation of H-4471A to H-4471, signed by an authorized quality representative, showing that the suffix is an internal forging-lot identifier and that the three forgings originate from the same heat. If the suffix represents a different heat, the correct MTR and certificates must be supplied. For impact testing, the supplier should provide the test report with specimen orientation, test temperature, absorbed energy values, and the relationship of the test coupon to the forgings. The inspector should verify that the test coupon was taken from the same heat and condition and that the testing laboratory is qualified. Any missing results should be resolved by testing or by an approved deviation, not by the certificate alone.
3. What corrective action and reporting should be expected after release is corrected?
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The supplier should investigate why the marking and documentation review did not catch the mismatch before final release, and why the certificate claimed impact testing without supporting results. Corrective actions could include a documentation checklist that cross-checks markings against MTRs, a certificate review step before shipment, and training for marking and records personnel. The inspector should document the nonconformance, the verification performed, and the corrected records in the final report. If the issue suggests a systemic records-control weakness, the purchaser may require a supplier quality system review or increased documentation surveillance on subsequent orders.