Reasons For Evaluating Only Corrosion Defects

  • Most third party damage is not stress-free
  • Impact by a trencher or auger induces local stress and deforms the pipe
  • Dissipation of this stress may not be instantaneous
  • Impact by a trencher or auger can cause a gouge and microcracks in the steel. The residual stress in the pipe can cause the micro cracks to propagate over time resulting in delayed failure when the micro-cracks reach critical depth.
  • It is for these reasons that the early B31G Criterion was not recommended for the evaluation of dents, dings, or gouges. The application of the criterion was limited to:
    • Corrosion only on weldable pipeline steels
    • Defects that have relatively smooth contours- i.e. loss due to corrosion
    • Corroded areas that do not touch
  • Excluded were corroded areas in welds or grooves and gouges caused by mechanical damage. The objective was to evaluate structural integrity only under internal pressure, i.e., not secondary stresses.

Related Links

Table of Pages
  1. Pipeline HUB User Resources
  2. AC Mitigation PowerTool
  3. API Inspectors Toolbox
  4. Horizontal Directional Drilling PowerTool
  5. Crossings Workflow
  6. Pipeline Toolbox
  7. Encroachment Manager
  8. PRCI AC Mitigation Toolbox
  9. PRCI Thermal Analysis for Hot-Tap Welding
  10. PRCI River-X
  11. PRCI RSTRENG
  12. RSTRENG+
  13. Ad-hoc Analysis
  14. Database Import
  15. Data Availability Dashboard
  16. ESRI Map
  17. Report Builder
  18. Hydrotest PowerTool
  19. Investigative Dig PowerTool
  20. Hydraulics PowerTool
  21. External Corrosion Direct Assessment Procedure – RSTRENG
  22. Canvas
  23. Definitions
  24. Pipe Schedule and Specifications Tables