SERVICE PERFORMANCE OF A DRILLING UNIT

The semi-submersible drilling unit 'Sea Quest' entered service for BP in July 1966 and has operated exclusively in the North Sea up to the end of 1973. For the past three years the unit has been drilling in water depths ranging from 88 to 143 m and in the area north of latitude 56 deg North in the oil bearing prospects, in the course of which the Forties oil field was discovered. Throughout this period the service performance has been continuously monitored. In addition special trials have been performed in which the motions and structural stresses were compared with measured wave heights. Service performance data for approximately 700 days are summarized and presented in terms of the percentage time for which particular values of roll, pitch and heave are exceeded. Estimates are made of the extreme values likely to be experienced in an average year and in an average 20 year period. Stress response functions evaluated during the special trials are compared with calculated values. Some comments are made regarding the present methods of stressing these units, and the validity of the statical stability criteria.

  • Availability:
  • Corporate Authors:

    Royal Institution of Naval Architects

    10 Upper Belgrave Street
    ,   USA 
  • Authors:
    • Bell, A O
  • Publication Date: 1974-10

Media Info

  • Features: References;
  • Pagination: p. 243-258
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00084542
  • Record Type: Publication
  • Source Agency: Engineering Index
  • Files: TRIS
  • Created Date: May 19 1975 12:00AM