Valve Body and Trim Material Certification Requirements

Material certification and traceability are fundamental requirements for valves in pressure systems. International standards define material specification, testing, marking, and documentation requirements to ensure materials meet design assumptions.

Material Test Reports (MTRs)

• ASTM material specifications define chemical composition and mechanical property requirements

• MTRs provide heat/lot traceability from mill to finished valve

• Certified material test reports (CMTRs) include mill signature and independent lab verification

• EN 10204 Type 3.1 or 3.2 certification levels specified in European procurement

Positive Material Identification (PMI)

PMI uses portable X-ray fluorescence (XRF) or optical emission spectrometry (OES) to verify alloy composition of valve components. PMI is mandatory in many process plants to prevent installation of incorrect materials. Random PMI programs catch material mix-ups not revealed by visual inspection alone.

Impact Testing Requirements

• ASTM A333/A350: Impact test requirements for low-temperature service

• Charpy V-notch testing at minimum design temperature

• CVN energy requirements vary by material specification and wall thickness

• Supplementary impact testing required below -20°F (-29°C) for carbon steel

Pressure-Retaining Part Requirements

ASME B31.3 and B31.1 require pressure-retaining components to be manufactured from listed materials with documented properties. Unlisted materials require engineering evaluation and additional documentation. Weld repairs to pressure parts require qualified welding procedures and welder certifications.

Documentation Package

Complete valve documentation packages include MTRs for all pressure parts, PMI reports, NDE records, heat treatment records, dimensional inspection reports, and pressure test certificates. Documentation should be retained for the plant life and transferred with valve ownership.