Drilling the First Ultra Deepwater Wells Offshore Malaysia

摘要

This paper will address all of the planning and logistical issuesinvolved with drilling the first ultra deepwater wells off thecoast of Malaysia. Murphy Sabah Oil recently contracted theDiamond Offshore Ocean Baroness to drill wells in waterdepths ranging from 1300 m to 2000 m of water.Since a moored rig was used for the project long rangeplanning and engineering was required to moor the rig inworld record mooring depths without any boats or contractorsin the area with ultra deepwater mooring experience.Well design and strategy required the initial string ofconductor casing to be placed at depths exceeding 750 mbelow the mudline. Due to possible high pore pressures, theriserless section was designed to be drilled with water basedmud. The paper will address the logistical and planning issuesinvolved with transporting mud volumes offshore in excess of15000 bbls in an area without deepwater logistical support.The selection and procurement of proper “deepwater” cementwill also be discussed. Synthetic based mud was also a part ofthe drilling strategy. Since synthetic fluids had never beenused before in this area, the planning phase for this fluidrequirement will offer several lessons learned for industry.Well design was further complicated by an abnormallyhigh temperature profile that brought on several well designand strategy issues.The well was also the initial project for a recentlyupgraded rig, which added to the complexity of themobilization along with commissioning requirements. The righad minimal downtime during the project.