API 579 Part 4 & Part 5 – General and Local Metal Loss
INSPECT performs general and local metal loss assessments and quickly generates detailed reports. INSPECT’s 3D models take the guess work out of verifying that the metal loss has been correctly entered. Since other flaws such as pitting are often present within metal loss regions, INSPECT detects pitting overlaid onto the metal loss and factors this in accordingly. Other features include:
Level 1 and 2 assessments for both Part 4 and Part 5.
Local metal loss assessments for nozzles are included. These Level 2 assessments follow the rules of API 579, Part 4 (188.8.131.52). INSPECT’s 3D modeling capabilities simplify this process providing concise nozzle assessments quickly.
PTR (point thickness reading) and CTP (critical thickness profile) assessments.
CTP values may be entered manually or input via a measurement grid. Grids calculate the CTP values automatically.
Scaled grids shown on the model to represent areas of metal loss.
Visual representations of CTP profiles are given in the report and dialog.
Part 5 metal loss reports with plots of the remaining strength factor (RSF) and interpolated tensile strength factor (TSF) with values plotted for each individual flaw. Flaws inside the dished region of formed heads use the spherical shell equations for the MAWP and the minimum required thickness. An option is available to automatically detect when the flaw is inside the dished region. Joint efficiencies may be defined for each flaw’s particular location.
Calculations from API 579 Annex A along with ASME Section VIII Division 1 are used to evaluate the flaw. ASME Section VIII Division 2 equations can be used by turning on the ASME VIII, Appendix 46 option (formally known as Code Case 2695).
Supplemental loads due to wind, seismic, weight, lateral forces and vertical loads for Part 4, Level 2 assessments.
Integration with Olympus Data loggers (read/write capabilities).
Part 5 – Groove-like Flaws
API 579 Part 5 groove-like flaw assessments can be utilized in INSPECT to perform “What if” scenarios for possible remedies to flawed areas. For example, what would my assessment look like if I grind out a crack or a metal loss area into a groove-like flaw? Groove-like flaws may also be combined with pitting damage (Part 6).