Assessment of Performance of Deepwater Floating Production Facilities During Hurricane Lili

摘要

Several deep water floating production facilities are currently in operation in the Gulf of Mexico, with many more planned for the future. Hurricane Lili provided an opportunity to verify the performance of such units in the field during a major environmental event. The present study collected and assessed information on the performance of deepwater production facilities that were impacted by Lili, aiming to provide further insight into critical design issues and develop recommendations for improvement in design and operation practices for deep water floating production installations. The principal conclusions and recommendations are summarized below. 1st Objective: Identify the units that were closest to Lilis track and most likely to be impacted by it. The units that were closest to Lili were: ChevronTexacos Genesis Spar and Typhoon Mono-Column Tension Leg Platform (TLP), ENIs Morpeth and Allegheny Mono-Column TLPs, Conocos Jolliet TLP, Shells Brutus TLP and El Pasos Prince TLP. Typhoon was the unit located closest to Lilis track and subjected to the most severe environmental conditions. 2nd Objective: Collect information on any observed damage to such units and assess its significance. If significant structural damage was observed, identify potential abnormal loading (such as loss of air gap or collision) and failure mechanisms. In general, no damage to structural members was observed. Inspection data indicated damage to secondary structures located in the air gap such as ladders and boat landings (up to 55ft above sea level) but no evidence of air gap loss was found. In general, the units were subject to motions that led to damage of some topsides equipment. 3rd Objective: Assess the environmental conditions during Lili and if these were of a sufficiently large magnitude to test the design of the units affected. Identify and collect any measured data that would assist in assessing the performance of the units. Verify if the performance of the units during Lili stayed within their design limits. The hindcast study and the measurements obtained of wind (for Brutus) and of current (for Genesis) suggest that the environmental conditions during Hurricane Lili were sufficient to test the response of Typhoon, Brutus and Genesis relative to their design events.