Advanced BHA Modeling and

Drilling & Evaluation Technology

to Improve Efficiency in Shale Gas

Horizontal Drilling

© 2011 Baker Hughes Incorporated. All Rights Reserved.

Shale Gas Typical Drilling Challenges

Challenge /Objective

• Performance Optimization

• Wellbore Placement

• Bit & Motor Durability

• Excessive Sliding

• Extended Reach

• Borehole Quality

• PDC Bit Vibrations

• High Stick-Slip, Torque

• Staying in Zone (Lateral)

• Hole Cleaning, Balling

• Pack Offs, Stuck

• Faulted/NF, Abrasive Format.

Impact

• Reduced ROP, Days on Well

• Production Optimization

• Bit Trips – NPT

• Reduced ROP, Days on Well

• Production Optimization

• Problems Run CSG, Red. ROP

• Reduced ROP, Days on Well

• Reduced ROP, Days on Well

• Production Optimization

• Reduced ROP, Days on Well

• Increased Days on Well

• Reduced ROP, Days on Well

Major Shale Gas Drilling Challenges:

• The formations are difficult – maximize the trip time• Optimize drilling to increase ROP• How to steer to the right place in the formation

The Value of Bit and BHA Stability

Drilling system stability has a significant influence on overall reliability (i.e. lessvibration = less bit, BHA, and drill string damage)

– Equipment failure is the largest source of non-productive time

– Drilling tool failures specifically cited as a top source for NPT

14%

5%6%

8%

9%

10%

10%

11%

16%

18%

18%

25%

0% 10% 20% 30%

EQUIPMENT FAILURE (IN GENERAL)

WEATHER DELAYS

DOWNHOLE WELLBORE INSTABILITY

RIG FAILURE

INEXPERIENCED PERSONNEL

STUCK PIPE

DRILLING TOOL FAILURES

EQUIPMENT AVAILABILITY

LOST CIRCULATION

CASING OR WELLHEAD FAILURE

MANAGEMENT INDECISION/ DISAGREEMENTS

ALL OTHER (12 ISSUES)

Source: Welling & Company

Survey Question: What is your greatest source of NPT?

Drilling Engineering / Optimization

• Internal education and certification program for DrillingApplication Engineers

• AKS - Application Knowledge Store

• Advantage Engineering Package

Torque & Drag, Hydraulics

• BHASysPro Analysis Software

gravity

bending moment maxima

Bending Moment Color ScaleBending Moment Color Scale

MinimumMinimum MaximumMaximum

gravitygravity

bending moment maxima

Bending Moment Color ScaleBending Moment Color Scale

MinimumMinimum MaximumMaximum

Reducing Days on Well by Drilling Optimization

5

Downhole Tools,Analytical Tools and

Modeling

Structured Processes& Engineering

Training

Offset Well and DullBit Analysis

RPM change

Stabilizer in thissectionat RPM change

RPM nearcriticalspeed,

then BHAenters hardformation

Appears to resultfrom stabilizers

hanging on ledges

and allowing bit toside cut

Fri

ab

leF

orm

ati

on

Fri

ab

leF

orm

ati

on

BHA Modeling

Torque, Drag, Hydraulics Modeling

AXIAL LATERAL TORSIONAL

Downhole dynamics measurement

DF Designs & ECD

BHASysPro - Fit for Purpose BHA

Advantage Software for Hydraulic Optimization

•From basic hydraulic optimisation•To detailed split flow analysis

•To guarantee flawless deployments

Going farther faster – Drilling Optimization (BarnettShale example)

• Premature Damage to PDC Bits• Low ROP, More Bits Required• High Cost Per Foot• High Torque and Drag• Excessive Slide Drilling (Oriented) in

Lateral Interval• Damaging Drill String Vibrations• Low Reliability/Performance of Downhole

Tools

Drilling Challenges

Closer to Bit - Minimum Vibration

Away from Bit - High Vibration

Buckling Load Analysis/ BHA Re-design

Critical Speed Analysis – OptimizeDrilling Parameters

Drilling Optimization (Barnett Shale Example)

6 Wells Drilled Prior to Optimization @ 32 ft/hr8 Wells Drilled After Optimization @ 57 ft/hr

80% Increase inAverage ROP for

Spud to TD

5+ DAYS SAVED

Optimization• Modified PDC Bits• Model Re-design BHA- torque, drag, hydraulics

• Optimized Parameters -WOB, Rotation

• Critical Speed Analysisto reduce vibration

• Result - increase ROP

Barnett Shale – Drilling Performance

Average days per wellreduced from

31.2 to 15.5 days

Average rotating hours per wellreduced from

330 to 181 hours

Decrease risk and reduce time on well utilizingRotary Steerable Tools – Shale Gas Laterals

• Decrease risk

– Improved borehole qualityallows for casing runningoperations to be completedwith less risk for extendedreach laterals

• Reduce time on well

– Eliminating orient and slidetime associated withsteerable motor drillingimproves overall effectivepenetration rate

Rotary Steerable

Steerable Motor

Rotate

Slide

12

Well Details• Well Details• Location: Webb County• Shale Play: Eagle Ford• Hole Size: 8 ¾” Curve and Lateral

Challenges• Low ROP’s• Several Bits Required• Inconsistent BUR’s in Curve• Trips to change BHA’s• Reduced Drilling Efficiency• High Cost per foot• Difficulties staying in Zone

Eagle Ford - Webb County – AutoTrak G3 / OnTrak

Solution• 8 ¾” HCC Bit (DP505X PDC Bit)• 6 ¾” AutoTrak G3 RSS• 6 ¾” OnTrak LWD

Project Results• Drill Curve from 23 deg inclination and land the curve• Continue Drilling Entire Lateral of 3,748 ft to TD• Total Footage: 5,113 ft• Rotating Hrs : 97.75 hrs• Average ROP: 52.3’/hr• Eliminated Reaming• Smoothly Ran Liner to Bottom• Consistent BUR’s• Stayed in Desired Zone

© 2009 Baker Hughes Incorporated. All Rights Reserved.

Woodford Shale – Rotary Steerable

Rotary Steerable Improved ROP by 15%

19.2

16.8

15.5

16

16.5

17

17.5

18

18.5

19

19.5

Lateral BHA 1:

AutoTrak eXpress

Lateral BHA 2:

Conventional

RO

P(f

t/hr)

Rotary steerable Reduced Cost/ Foot by 7%

$166

$179

$155

$160

$165

$170

$175

$180

Lateral BHA 1:

AutoTrak eXpress

Lateral BHA 2:

Conventional

Co

st/

foo

t($

)

Tru

eV

ert

ical

Dep

th(f

t)

Planned WellpathActual Wellpath

SteeringUnit

Power &Telemetry

MWD ProbeAssembly/NMCSDP

FlexStabilize

r

NMStab

AutoTrak Express®

Saved 4 Days of Rig Time

12.400

13.400

14.400

15.400

16.400

17.400

325 425 525 625 725 825

Drilling Hours

De

pth

(ft)

Offset drilled withConventional Assembly

AutoTrak Express® Well

AutoTrak®

eXpress In

AutoTrak®

eXpress Out

Woodford Shale – Rotary Steerable

Rotary Steerable Improves ROP by 115%

23.2

46.4

21.518.8

0

10

20

30

40

50

Conventional

BHA Run 1

AutoTrak BHA

Run 1

Conventional

BHA Run 2

AutoTrak BHA

Run 2

RO

P(f

t/h

r)

Rotary Steerable Reduces Cost/ft by 34%

$137

$94

$143$150

$-

$20

$40

$60

$80

$100

$120

$140

$160

Conventional

BHA Run 1

AutoTrak BHA

Run 1

Conventional

BHA Run 2

AutoTrak BHA

Run 2C

ost/

foo

t($

)

SteeringUnit

Power &Telemetry

MWD ProbeAssembly/NMCSDP

FlexStabilize

r

NMStab

Maximizing production by optimizingwellbore placement –Shale Gas

• Reservoir Navigation

– Full suite of formationevaluation tools andservices to steer to thereservoir “sweet spot”

Reservoir Navigation – Woodford Shale

Project Results Well was maintained in target zone Reservoir Navigation Services Multiple Propagation Resistivity Azimuthal Gamma Ray Gamma Ray Imaging Annular and Bore hole pressure

Fig.1: RNS CROSS SECTION – Well A

Fig.3: RNS CROSS SECTION – Well B

Fig. 2: Gamma Image of Well A

Fig. 4: Gamma Image of Well B

LWD Image in Shale Gas

17

Breakouts

RockStrength

Gamma

LWD Can be used to identify:

• Fracture

• Lithoface good for fracturing

• Optimization of perforating interval

• Optimization of packer placement

• Fracturing length

Integrated fracturing design

@ 2009 Baker Hughes Incorporated. All Rights Reserved

Forestburg Carbonate

© Baker Hughes Incorporated. All Rights Reserved.

Faults and Fractures in Barnett Shale Horizontal Well

Barnett Shale Forestburg Carbonate

Barnett Shale

Fault Undetectable on 3D seismic