FACTORS AFFECTING PIPELINE FLAW DETECTION AND MEASUREMENT. ANNUAL REPORT, MAY 1996-APRIL 1997

This report focuses on two techniques for pipeline flaw detection and measurement: Magnetic Flux Leakage (MFL) and Remote Field Eddy Current (RFEC). A number of factors influence MFL signals, the least understood of which are stress and the variation in magnetic properties. In addition to bulk stress, local defect-induced stress concentrations can influence the MFL result significantly. This project therefore continues fundamental research on the effects of line presure stress on MFL signal patterns. Defect-induced stress concentrations have been determined using neutron diffraction and magnetic Barkhausen noise (MBN) measurements, for correlation with MFL results. Finite element calculations have also been carried out to determine the effects of magnetic anisotropy on MFL signals from pits of different shapes. First estimates of stress correction factors for MFL signals have been produced.

• Supplemental Notes:
  • Sponsored by Gas Research Institute, Chicago, IL.
• Corporate Authors:

  Queen's University, Ontario

  Department of Physics
  Kingston, Ontario  Canada  K7L 3N6
• Authors:
  • Atherton, D L
  • Clapham, L
  • Czura, W
  • Weyman, Y
  • Yu, Yongtao
  • Zhang, Y
  • Mandal, K
  • Sabet-Shargi, R
• Publication Date: 1997-5

Language

• Japanese

Media Info

• Pagination: 110 p.

Subject/Index Terms

• TRT Terms: Electromagnetic properties; Finite element method; Flaw detection; Fluxes; Leakage; Maintenance; Neutron activation analysis; Pipelines; Remote sensing; Stresses
• Uncontrolled Terms: Magnetic flux
• Old TRIS Terms: Magnetic flaw detection; Pipeline maintenance; Stress concentrations
• Subject Areas: Maintenance and Preservation; Pipelines; Terminals and Facilities;

Filing Info

• Accession Number: 00744705
• Record Type: Publication
• Report/Paper Numbers: GRI-97/0264
• Files: TRIS
• Created Date: Jan 19 1998 12:00AM