API 579-1 Part 3 Brittle Fracture Assessments
API 579-1 Part 3 requires a brittle fracture assessment (material toughness check) before proceeding with the majority of flaw assessments. This is provided in INSPECT by specifying that a Part 3 brittle fracture assessment be done on the flaw being investigated. Part 3 brittle fracture assessments are derived from ASME VIII, paragraph UCS-66 and no software handles this better than Codeware’s.
INSPECT includes both level 1 and level 2 assessments for carbon and low alloy steels. Assessments are performed at the specified Critical Exposure Temperature (CET) instead of the MDMT as used in UCS-66. In addition, INSPECT runs multiple Part 3 assessments for each flaw and produces a Minimum Allowable Temperature (MAT) curve. These curves plot MAT versus pressure and help speed up the creation of equipment Integrity Operating Windows.