SubSea MudLift Drilling Joint Industry Project: Delivering Dual Gradient Drilling Technology to Industry

Abstract

SubSea MudLift Drilling Joint Industry Project: Delivering Dual Gradient Drilling Technology to Industry K.L. Smith; K.L. Smith Conoco Search for other works by this author on: This Site Google Scholar A.D. Gault; A.D. Gault Conoco Search for other works by this author on: This Site Google Scholar D.E. Witt; D.E. Witt Conoco Search for other works by this author on: This Site Google Scholar C.E. Weddle C.E. Weddle Cherokee Engineering Search for other works by this author on: This Site Google Scholar Paper presented at the SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, September 2001. Paper Number: SPE-71357-MS https://doi.org/10.2118/71357-MS Published: September 30 2001 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Smith, K.L., Gault, A.D., Witt, D.E., and C.E. Weddle. "SubSea MudLift Drilling Joint Industry Project: Delivering Dual Gradient Drilling Technology to Industry." Paper presented at the SPE Annual Technical Conference and Exhibition, New Orleans, Louisiana, September 2001. doi: https://doi.org/10.2118/71357-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 Annual Technical Conference and Exhibition Search Advanced Search AbstractIn early 1996, a consortium of deepwater drilling contractors, operators, service companies and a manufacturer gathered to discuss potential approaches to "riserless drilling", also known as "dual gradient drilling". This technology overcomes a significant deepwater drilling challenge: eliminating some of the casing strings necessitated by the relatively high pore pressures and low formation strengths found in areas like the deepwater Gulf of Mexico.That initial workshop led to what has become one of the largest and most significant joint industry projects (JIPs) in the history of our industry: the SubSea MudLift Drilling JIP. The JIP's overarching goal became to provide a total solution for dual gradient drilling, that is, both hardware and the methodology to safely and efficiently use that hardware.Five years and nearly 50 million dollars later, this JIP has succeeded in that goal.This paper, the first in a series of three on SubSea MudLift Drilling (SMD), will present highlights of the history of the project, its organization and its management (see also SPE 71358 and SPE 71359). The information presented here demonstrates the level of effort necessary to produce a ready-for-application technology, and will assist anyone planning a major JIP to deliver a complex new technology.Additionally, it will discuss the development of the SMD equipment, the preparation of SMD-specific drilling and well control procedures and the complementary relationship between those procedures and the equipment design. This paper will verify the integrity of the process used to develop these procedures, and it will help the reader understand the SMD system and techniques developed by the SMD JIP.IntroductionInterest in the development of a dual gradient drilling system arose in the early 1960s. Then, the goal was to eliminate the riser, thus the concept was originally designated "Riserless Drilling". At the time, existing technological capabilities were insufficient for the task. Moreover, the need was not great; conventional riser-based technology proved adequate for the water depths contemplated.The push for viable dual gradient drilling technology was revived in the 1990's and made more urgent by several significant deepwater discoveries in the Gulf of Mexico. Lease sales indicated strong interest in deepwater blocks and competition for drilling rigs with deepwater capabilities was intense. Because these rigs were in short supply, operators and contractors were motivated to find ways to extend the capabilities of shallow water drilling rigs. The dual gradient drilling concept appeared to provide a way to reduce riser weight and station-keeping requirements, as well as mud volumes. This would allow smaller rigs to move into deeper water.Ultimately, the driver to developing dual gradient drilling became the need to manage the narrow margin between pore pressure and fracture pressure gradients in deepwater. This has been well documented, as have the advantages offered by the technology.1,2,3 These advantages include:Fewer casing strings are required to reach TD.Larger wellbores can be drilled to accommodate larger production strings and designer completions with increased flow capacity (Figure 1).Geologic objectives can be attained at a lower cost.Loss of circulation and associated well control problems are less likely to occur.Complete riser margin is possible, reducing disconnect well control hazards.Drilling flat-time is reducedThe seawater-filled riser lightens the riser, lessening tensioning requirements.The water depth capabilities of smaller rigs may be extended. Keywords: annular pressure drilling, personnel, participant, contractor, spe 71357, jip, drilling operation, well control procedure, dual gradient drilling technology, dual gradient drilling Subjects: Drilling Operations, Pressure Management, Pipelines, Flowlines and Risers, Strategic Planning and Management, Dual gradient drilling, Risers, Project management This content is only available via PDF. 2001. Society of Petroleum Engineers You can access this article if you purchase or spend a download.