Engineering, planning, design and the first two years of implementation of a five year underwater inspection programme of a major North Sea platform jacket, Occidental of Britain Inc., Piper Alpha Jacket, are described. The programme was developed to ensure the structure was performing as designed and to secure re-certification from statutory bodies within the five year re-certification period. Basic inspection types include general visual without cleaning, detailed non-destructive testing with prior cleaning, cathodic protection potential survey, and measurement of selected critical dimensions. Areas considered include specific jacket nodes below the water line, risers, cathodic protection system, sump and pump caissons, and a general visual inspection of the jacket to ensure member integrity. The first year's inspection programme revealed damage to the cathodic protection, and excellent general integrity of the jacket some three years after initial installation. The programme was implemented with a dynamically positioned saturation diving vessel, especially designed platform mounted surface diving package, and a saturation diving system mounted on an adjacent semi-submersible construction support vessel.

  • Supplemental Notes:
    • Proceedings of the Eleventh Annual OTC held in Houston, Texas April 30-May, 1979, Volume 1.
  • Corporate Authors:

    Offshore Technology Conference

    6200 North Central Expressway
    Dallas, TX  United States  45206
  • Authors:
    • EDWARDS, W R
    • Hargreaves, DMG
  • Publication Date: 1979

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 00195851
  • Record Type: Publication
  • Source Agency: Offshore Technology Conference
  • Report/Paper Numbers: Volume 1 Proceeding
  • Files: TRIS
  • Created Date: Jul 31 1979 12:00AM