Valve Traceability and Material Certification Requirements

Material traceability links every valve component to its original mill certificate, ensuring that the physical properties and chemistry of pressure-retaining materials are verified and documented. Traceability failures have resulted in field failures and regulatory penalties.

Why Traceability Matters

Carbon steel and alloy steel valves for pressure service must meet minimum tensile strength, yield strength, and impact energy requirements. Without traceability to heat-specific mill test reports (MTRs), there is no assurance that the material in service meets the specification.

Required Certifications

Material Test Report (MTR) / Certified Material Test Report (CMTR): chemical analysis and mechanical properties by heat numberPositive Material Identification (PMI): field verification of alloy content by XRF or OESImpact test certificates: required for low-temperature service materialsHeat treat records: normalized, quenched and tempered, solution annealed as applicable

PMI Programs

Positive Material Identification programs use portable XRF or optical emission spectrometers to verify alloy composition in the field. PMI is mandated by API 578 for alloy materials in high-temperature hydrocarbon and HF acid service. PMI before installation prevents wrong-material incidents.

Marking and Identification

Valve bodies should be marked with heat or lot number, material grade, and pressure class per MSS SP-25. Color coding (marking paint) per purchaser's specification helps field identification. Material markings must be visible after painting.

Archive MTRs in valve data book with cross-reference to serial number and tagRequire PMI on all alloy valves NPS 1 and larger before hydrotestReject valves with missing or illegible heat markingsMaintain PMI records in plant inspection database linked to tag number