Deepwater Drilling with Lightweight Fluids - Essential Equipment Required (2001)

Deepwater Drilling with Lightweight Fluids - Essential Equipment Required D.M. Hannegan; D.M. Hannegan Weatherford Search for other works by this author on: This Site Google Scholar A.T. Bourgoyne, Jr. A.T. Bourgoyne, Jr. Petroleum Services International Search for other works by this author on: This Site Google Scholar Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 2001. Paper Number: SPE-67708-MS https://doi.org/10.2118/67708-MS Published: February 27 2001 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Hannegan, D.M., and A.T. Bourgoyne. "Deepwater Drilling with Lightweight Fluids - Essential Equipment Required." Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 2001. doi: https://doi.org/10.2118/67708-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE/IADC Drilling Conference and Exhibition Search Advanced Search AbstractNew equipment described in this paper has been developed for employing underbalanced drilling techniques on a floating drilling rig. Field trials of this equipment are being conducted on a semi-submersible vessel in the Albacora Field of the Campos Basin located offshore Brazil. The test is being conducted in a partially depleted formation with a pore pressure equivalent to approximately 7 lb/gal. The formation will be drilled slightly overbalanced during the test.IntroductionRecent emphasis on underbalanced drilling techniques for reducing drilling costs and improving formation productivity has led to major improvements in rotating control heads and other equipment needed to employ this technology. The rotating seal permits drilling ahead with some surface annular pressure. The range of field conditions for which underbalanced drilling technology can be applied has widened rapidly as the working pressure ratings of the rotating seals have increased. Also, operators have learned that significant cost savings can often be achieved even in areas where underbalanced drilling is not practical, by using underbalanced drilling equipment to safely drill with a reduced amount of pressure overbalance. Approximately one third of the land rigs working in the U.S. and Canada today use a rotating control head at some point in the drilling program. The use of this equipment in marine environments is also growing. The authors are aware of over 80 wells in marine environments that have made use of this technology. In the southern North Sea, rotating control heads have been used on over 20 wells drilled from jackups.Described in this paper are current efforts to extend this technology to deeper water depths and floating drilling operations. New equipment has been developed that will allow gas to be injected in the drill string to reduce the effective drilling fluid density while drilling and to safely take returns through the marine riser in a slightly pressurized condition. Field trials of this equipment are to be conducted on a semi-submersible rig offshore Brazil.The term "lightweight fluids" is sometimes used to describe drilling fluid and gas mixtures that produce an effective fluid gradient less than an unweighted mud. The use of underbalanced drilling techniques to produce a lightweight fluid is often desirable when drilling partially-depleted formations. When lightweight drilling fluids are used for underbalanced drilling operations, significant amounts of formations fluids, including oil and gas, can be produced while drilling. Some means of pressure containment while drilling is required at the surface for the annulus. In addition, efficient separation of the produced fluids, the drilling fluid, and the gaseous phase returning from the well is required. This is more challenging on a floating vessel because of the reduced space and load capacity that is generally available.Offshore Drilling with Lightweight Fluids Joint Industry Project.During 1997 and 1998 PetroBras formed a Joint Industry Project (JIP) with several other operating and service companies. The objective of this Offshore Drilling with Lightweight Fluids JIP is to adapt lightweight drilling fluid equipment and techniques for use in deepwater floating drilling applications.The JIP has conducted several studies on critical aspects of implementing lightweight drilling fluid techniques in deepwater applications. These first phase studies focused on selecting and/or developing predictive models for use in designing and planning operations which use lightweight drilling fluids. The studies investigated drilling hydraulics, cuttings transport, formation damage, well control, and wellbore stability. Keywords: application, drilling operation, bourgoyne, separator, annular pressure drilling, assembly, offshore brazil, underbalanced drilling technique, well control, upstream oil & gas Subjects: Drilling Operations, Pressure Management, Drilling Fluids and Materials, Well control, Drilling fluid management & disposal This content is only available via PDF. 2001. 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