extended reach drilling and completion solutions in deepwater drilling challenges in deepwater erd

Extended Reach Drilling and Completion Solutions in Deepwater

Drilling Challenges in

Deepwater ERD


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


Technical Keys to Success• Planning• Mud lubricity• Modeling• Drillstring design• Wellbore stability• Hole cleaning• Fit for purpose drilling tool


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


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


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


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


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


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


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


At Bit Inclination Measurement (AIM*)

• Single axis inclination sensor • 200hr+ operating time• Wireless telemetry• Available from 5-7/8” to 26” hole

sizes


Power Drive

• PowerDrive 900• PowerDrive 675• World Record reach - 11 278 m

MD• Maximum dogleg capability - 8

°/30 m


Power Drive - Direct


MWD Technology

• Flexible frequency control for max. signal strength

• World record depth reached - 11278 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


Increase Drillstring and Bit LifeBHA whirling in vertical hole

Multi axis shocks • Reduce drillstring fatigue • Reduce borehole enlargement • Increases ROP/bit life

Larger shocks result in more shock counts


Accurate control of ECDModeled 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


Preliminary Planning


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: N7 0 0.000 Lon: E10 30 0.000

North: 10774021.82 m East: 665701.59 m

Grid Conv: 0.1828° Scale Fact:0.9999

Magnetic Parameters

Model: BGGM 1999

Dip: -10.912° Mag Dec: -2.016°

Date: February 29, 2000 FS: 33199.7 nT

New StructureSTRUCTURE

AF Gabon TotalFIELD

New WellWELL

TotalFina

0 400 800 1200 1600 2000 2400 2800

4000

3600

3200

2800

2400

2000

1600

1200

800

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 ViewT

rue

Ver

tical

Dep

th (

1 cm

= 2

00 m

eter

s)

Vertical Section Departure at 0. (1 cm = 200 meters)


0

50

100

150

200

250

300

350

400

450

0 5000 10000 15000 20000

MD (ft)

Ho

ok

Lo

ad (

klb

s)

DrillSAFE Tripping Loads Analysis

8 1/2” bit at TD 5994m (19665 ft)40%

20%

20%40%

0%


2500

3000

3500

4000

4500

1 1.05 1.1 1.15 1.2 1.25 1.3 1.35 1.4

Pressure Gradient (SG)

TV

D

(m)

20" @2800m

13 3/8" @3100m

9 5/8" @3700m

planned TD 4100m (TVD)

Possible Casing Schedule with Pressure Gradients

FPG

PPGp (1010)

PPGp (950)


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


2500

3000

3500

4000

4500

1 1.05 1.1 1.15 1.2 1.25 1.3 1.35 1.4

Pressure Gradient (SG)

TV

D (

m)

24“ csg @2800m

20“ csg @3100m

16“ csg @3700m or 13 3/8” csg

planned TD 4100m (TVD)

Possible Casing Schedule with Pressure Gradients

FPG

PPGp (1010)

PPGp (950)

26” or 28”” Hole section

22” x 24”” Underreamer hole section

17” x 20” Bicenter hole section

14 ¾” hole section or 12 1/4”

11 ¾” csg @ 4100m or 9 5/8” csg

10 5/8” x 12 ¼” Bicenter Tangentor 8 1/2” hole


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

extended reach drilling and completion solutions in deepwater drilling challenges in deepwater erd

Documents