In early 2003, the Glomar Jack Ryan dynamically-positioneddrillship drilled a well in the Great Australian Bight in 4308feet of water. This well was unique in that retrieval of thelong riser was required in advance of large, rapidly-developingseastates. Accurate seastate forecasting and on-sitemeasurements were key elements provided by the operator toensure that enough time was allowed to have the riser pulledand on deck in case well-specific operating criteria were to beexceeded. These seastates were established based ondiscussions between operator and drilling contractor personnelsupported by riser analysis results. Riser recoil analysis was agoverning factor so extensive work was carried out toinvestigate the potential for damage to the BOP stack andslack in the tensioner lines in case of anemergency disconnect.The subject well was the first drilled by a dynamicallypositioneddrillship in the Great Australian Bight since 1980.On this well, drilling operations were interrupted even morefrequently than they would be otherwise as the well timingextended into the higher seastates of Australia’s winter season.In the end, the well was successfully drilled despiteencountering several instances in which the significant waveheight was about 8 meters (26 feet). In each of theseencounters, the riser had been pulled and was on the deck, aswas called for by the riser management plan. This paperpresents an overview of the riser management carried out forthis well.
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