Extended Reach Drilling and Completion Solutions in Deepwater Drilling Challenges in Deepwater ERD

Extended Reach Drilling and Completion Solutions in Deepwater Drilling Challenges Long displacements Long open hole sections Hole stability issues Directional control and surveying practices ECD management Risk - cost of failure Continuous improvement to reduce cost Comprehensive contingency planning

Extended Reach Drilling and Completion Solutions in Deepwater Technical Keys to Success Planning Mud lubricity Modeling Drillstring design Wellbore stability Hole cleaning Fit for purpose drilling tool

Extended Reach Drilling and Completion Solutions in Deepwater Planning Optimization of directional well profile Terminal angle considerations –wellbore stability –completions /casing running Achievable build rates in soft unconsolidated formations Gradual angle-build approach provides: –significant torque reduction –improved sliding –improved tubular running

Extended Reach Drilling and Completion Solutions in Deepwater Mud Lubricity Complex issue affected by: –formation– hole cleaning –wellbore stability– cutting bed –filter cake– tortuosity, etc... In most projects OBM chosen for: –lubricity –inhibition properties Lubricants: little effect Biggest impact: oil/water ratio

Extended Reach Drilling and Completion Solutions in Deepwater Modeling T&D and hydraulics from PowerPlan drives rig selection Bit torque (dynamic conditions) difficult to predict –downhole WOB&TRQ measurements Friction coefficients calculated from offset data and real time data Engineering subroutines to read MWD data every foot, for monitoring of: –downhole torque/drag –wellbore stability –hole cleaning

Extended Reach Drilling and Completion Solutions in Deepwater Drillstring Design S135 drillpipe usually standard Strict control on –quality –material specifications –inpections Special thread compounds –nonheavy metal –high torque Double-shouldered tool joints: –7 1/2-in. for 5 7/8-in. drillpipe –40 to 60 % higher capacity

Extended Reach Drilling and Completion Solutions in Deepwater Hole cleaning Primary parameter: flow rate Models used to optimize flow rate High rpm (above 120): –no obvious benefits –leads to shocks and vibrations Alternating hi/low viscosity tandem pills can be useful Downhole weight/torque and APWD: –monitor hole cleaning effectiveness –rotating friction factor and drag Must circulate till cuttings removal complete

Extended Reach Drilling and Completion Solutions in Deepwater Fit for Purpose Drilling Tools Forward planning of signal transmission and detection is required Cost of failures high  Select proven reliable tools High flow rate specification tools 2-D Rotary Steerable 3-D Rotary Steerable Real time drilling solutions

Extended Reach Drilling and Completion Solutions in Deepwater PowerPak Motors Over 50 models from 2 1/8 in. to 11 1/4 in. PowerPak XP & GT extended power sections High flow versions: A700 rated to 1000 gpm Working on A975 capable of 2000 gpm

Extended Reach Drilling and Completion Solutions in Deepwater At Bit Inclination Measurement (AIM*) Single axis inclination sensor 200hr+ operating time Wireless telemetry Available from 5-7/8” to 26” hole sizes

Extended Reach Drilling and Completion Solutions in Deepwater Power Drive PowerDrive 900 PowerDrive 675 World Record reach m MD Maximum dogleg capability - 8 °/30 m

Extended Reach Drilling and Completion Solutions in Deepwater Power Drive - Direct

Extended Reach Drilling and Completion Solutions in Deepwater MWD Technology Flexible frequency control for max. signal strength World record depth reached m MD Flexible data frame format Two-way communication saves trips Continuous surveys save rig time High LCM tolerance-50 lbm/bbl medium nut plug High flow rate options 9 1/2-in.  2000 gpm 6 3/4-in  1000 gpm

Extended Reach Drilling and Completion Solutions in Deepwater Increase Drillstring and Bit Life BHA whirling in vertical hole Multi axis shocks Reduce drillstring fatigue Reduce borehole enlargement Increases ROP/bit life Larger shocks result in more shock counts

Extended Reach Drilling and Completion Solutions in Deepwater Accurate control of ECD Modeled vs. Actual ECD Key for Deepwater drilling Detect shallow water flows Detect cuttings loading and swab/surge effects Manage the pore pressure fracture grad window Minimize mud weight for optimum ROP Incorporated into ARC High flow options ARC6  800 gpm ARC 8 &9  1950 gpm

Extended Reach Drilling and Completion Solutions in Deepwater Preliminary Planning

Extended Reach Drilling and Completion Solutions in Deepwater Quality Control Date Drawn:01-Mar-2000 Drawn by: W.G. Lesso, Jr Checked by: uncontrolled Client OK: ______________ Astrid Marlin Gabon Displacement Review Surface Location Lat: N Lon: E North: m East: m Grid Conv: ° Scale Fact: Magnetic Parameters Model: BGGM 1999 Dip: ° Mag Dec: ° Date: February 29, 2000 FS: nT New Structure STRUCTURE AF Gabon Total FIELD New Well WELL TotalFina TD 5994 MD Build 3.00°/30 m Hold Angle 78° EOC 3880 MD KOP Seafloor 0° 2500 MD 9 5/8'' csg 78° 4070 MD 13 3/8'' csg 0° 3100 MD 20'' csg 0° 2800 MD Vertical Section View True Vertical Depth (1 cm = 200 meters) Vertical Section Departure at 0. (1 cm = 200 meters)

Extended Reach Drilling and Completion Solutions in Deepwater DrillSAFE Tripping Loads Analysis 8 1/2” bit at TD 5994m (19665 ft) 40% 20% 40% 0%

Extended Reach Drilling and Completion Solutions in Deepwater Possible Casing Schedule with Pressure Gradients FPG PPGp (1010) PPGp (950)

Extended Reach Drilling and Completion Solutions in Deepwater Challenges ECD limiting factor Solutions: –Improve mud properties,lower the rheology –Use 5 1/2” or 5 7/8” Drillpipe –Extra casing string for contingency Under reamers or Bicenter bits

Extended Reach Drilling and Completion Solutions in Deepwater

Summary Well design will require in-depth studies of: –Drilling fluid requirements –Borehole stability limitations –ESD and ECD characteristics –Well control and kick tolerance These factors along with completion and target requirement will determine the technical limits for the ultimate reach capabilities