CONSIDERATION OF FRACTURE MECHANICS ANALYSIS AND DEFECT DIMENSION MEASUREMENT ASSESSMENT FOR THE TRANS-ALASKA OIL PIPELINE GIRTH WELDS. VOLUME I

In anticipation of a request for waivers on defective girth welds in the Trans-Alaska oil pipeline, DOT requested assistance from the National Bureau of Standards (NBS) in evaluating the fracture mechanics analysis and the nondestructive evaluation (NDE) methods used to detect and determine dimensions of weld defects. NBS measured the required mechanical properties of the weld metal, developed and evaluated fracture mechanics methods to determine the allowable defect sizes, and evaluated various methods of measuring the size of defects present in the welds from existing field radiographs. Results of this investigation show that the fracture mechanics analysis can be used to determine the allowable defect sizes concerning the integrity of the pipeline, but that these analyses have not been experimentally verified at this time. Defect dimensions can be determined with sufficient accuracy to be useful in the fracture mechanics analyses if the radiographs are made under carefully controlled conditions. If the radiographs are not made with close control, the accuracy of the defect sizes may not be sufficient to permit their use in establishing allowable defect sizes.

  • Supplemental Notes:
    • See also PB-260 401
  • Corporate Authors:

    National Bureau of Standards

    Gaithersburg, MD  USA 

    Department of Transportation

    Office of Pipeline Safety, 1200 New Jersey Avenue, SE
    Washington, DC  USA  20590
  • Authors:
    • BERGER, H
    • Smith, J H
  • Publication Date: 1976-10-18

Media Info

  • Pagination: 184 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00145565
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: NBSIR-76-1154-Vol-1, DOT/MTB/OPSO-76/02
  • Contract Numbers: DOT-AS-70006
  • Files: NTIS, USDOT
  • Created Date: Jan 16 2002 12:00AM