Planning and Execution of Big Bore Wells - Offshore NW Australia

Abstract

Planning and Execution of Big Bore Wells - Offshore NW Australia S.P. Dolan; S.P. Dolan Woodside Energy Ltd. Search for other works by this author on: This Site Google Scholar G.J. Williams; G.J. Williams Woodside Energy Ltd. Search for other works by this author on: This Site Google Scholar R.J. Crabtree R.J. Crabtree Woodside Energy Ltd. 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-67820-MS https://doi.org/10.2118/67820-MS Published: February 27 2001 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Dolan, S.P., Williams, G.J., and R.J. Crabtree. "Planning and Execution of Big Bore Wells - Offshore NW Australia." Paper presented at the SPE/IADC Drilling Conference, Amsterdam, Netherlands, February 2001. doi: https://doi.org/10.2118/67820-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 AbstractTwo wells were spudded in August 1999, on the Woodside North Rankin A (NRA) gas / condensate production platform with the intention of completing them as Big Bore producers. These wells were drilled into the Perseus reservoir, which can be accessed from the NRA platform at a horizontal step out of approximately 3500m. The NRA platform is located 135km offshore from the North-Western coast of Australia.The Big Bore well design incorporates 9.5/8" production tubing to maximise production and subsequently halve the Unit Technical Cost (UTC) of Well Construction per unit of gas production ($/MMscf/d). Larger tubing is used as production from the highly permeable reservoirs is tubing constrained with the current 7.5/8" tubing. The additional cost of a Big Bore well is 10% when compared to the cost of a comparable conventional well.This paper will describe the Well Construction related Front-End Engineering, Detailed Planning and Execution phases. The paper does not describe work done by other disciplines such as Production Technology and Process Engineering.In particular, detailed engineering such as casing wear, integrity issues, major tasks hazard management, extensive communication requirements and equipment issues will be highlighted.Results and lessons learnt from the planning and execution phase are analysed with a view to future improvements in the continued development of the Big Bore well designs.IntroductionWoodside Energy Ltd. is operator of, and joint venture participant in, the North-West Shelf Venture, on behalf of BHP Petroleum (North West Shelf) Pty Ltd; BP Developments Australia Ltd; Chevron Australia Pty Ltd; Japan Australia LNG (MIMI) Pty Ltd; Shell Development (Australia) Proprietary Limited.The planning for the development of the Perseus gas field commenced in 1997. The Perseus reservoir contains multi-darcy clean sands that are highly productive. It is similar to the Goodwyn and North Rankin reservoirs which have been developed with wells which are completed with 7" and 7.5/8" tubing. These wells are tubing constrained and currently flow at up to 215 MMscf/d.At an early stage it was decided to use 9.5/8" production tubing for the Perseus field to obtain flowrates in excess of 350 MMscf/d. This also has the benefit over conventional 7.5/8" completed wells of using fewer wells and thus platform slots to produce a given quantity of gas and condensate.Front-End EngineeringThe Front-End Engineering was carried out using a multi-disciplinary team, working on not only subsurface aspects, but also such surface issues as flowlines and flaring capacity. However this paper concentrates on only the Well Engineering aspects of the planning. Keywords: liner, casing design, requirement, execution, integrity, upstream oil & gas, trssv, engineering, planning stage, collapse capacity Subjects: Casing and Cementing, Casing design This content is only available via PDF. 2001. SPE/IADC Drilling Conference You can access this article if you purchase or spend a download.