Platform requalification in three regions: Economics and API RP 2A Section 17 draft guidelines
- Unocal Corporation, Lafayette, LA (United States)
- Unocal Corporation, Brea, CA (United States)
Several offshore platforms have remained in operation past their original intended service life. Government regulations will be implemented in the near future requiring the demonstration of these platforms` continued structural fitness for purpose. Currently, draft reassessment guidelines have been written and issued as Section 17 of API`s RP 2A. Operators have been performing reassessments of existing structures over the past few years for economic reasons, prior to enforcement of new government regulations. UNOCAL has been developing and implement reassessment techniques in the Gulf of Mexico, offshore Southern California, and in the Cook Inlet, Alaska, as part of the company`s overall loss control program. These techniques have included deterministic and probabilistic methods, and have used such tools as linear and non-linear time history analysis, ultimate capacity (pushover) analysis, economic importance and structural reliability matrices, probability of failure calculations, and the evaluation of total system risk. Within the three regions mentioned, wave, seismic, and ice loads have been investigated. Structural upgrades, and load and consequence reduction measures, have been implemented where deemed necessary. Work on some of UNOCAL`s West Coast facilities is summarized in Bea and Craig, 1993. In this paper, relevant draft Section 17 guidelines will be compared against previous requalification work done in each of these regions. Key reassessment issues will also be highlighted, and improvements to draft Section 17 guidelines will be outlined.
- OSTI ID:
- 100705
- Report Number(s):
- CONF-950116--; ISBN 0-7918-1291-X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Modification to and applications of the guidelines for assessment of existing platforms contained in section 17.0 of API RP 2A
Platform assessment and requalification based on historic design codes for strength of tubular joints