A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP...

72
A Noble Drilling Corporation Subsidiary TT01-43 1 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001

Transcript of A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP...

Page 1: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

1

A Noble DrillingCorporation Subsidiary

TT01-43

Hollow SphereDual Gradient Drilling

System

Hollow SphereDual Gradient Drilling

System

JIP Kickoff Meeting

Dr. William C. MaurerSeptember 27, 2001

Page 2: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

25TT01-43

DOE Hollow SphereUnderbalanced Drilling

Project

Page 3: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

26TT01-43

Types of Flow Regimes

MISTFOAMLIQUID GASAERATEDLIQUID

Page 4: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

30TT01-43

Lightweight MudLightweight Mud

LIGHT WEIGHTMUDMUD HOLLOW SPHERES

5.84 ppg8.5 ppg 3.17 ppg0.70 S.G.1.02 S.G. 0.38 S.G.

Page 5: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

33TT01-43

Glass BeadsGlass Beads

Page 6: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

34TT01-43

Particle Sizes in Unweighted, Water-Based Mud

(After Bourgoyne Jr. et al, 1986)

.01 0.1 1 10 100 1000 10,000

Drilled Solids

SILT FINESAND

COARSESAND

GRAVEL

200

100

60 20

MESH

Solid

s Pe

rcen

tag

e

MICRONS

BentoniteSmallHollow

Spheres

Page 7: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

37TT01-43

Centrifuge TestCentrifuge Test

Page 8: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

38TT01-43

Desilter Tests

Page 9: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

39TT01-43

Oilfield Hydroclone(Moore et al., 1974)

Underflow Discharge(Cuttings)

Feed Chamber

Feed Inlet

Vortex Finder

Vortex

Overflow Opening(Hollow Spheres)

Page 10: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

46TT01-43

Golden State Drilling Rig Mud System

Page 11: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

47TT01-43

Mud ReturnsMud Returns

Page 12: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

50TT01-43

Dual Gradient Drilling Systems

Page 13: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

51TT01-43

Hydrostatic Gradients for Conventional

and Riserless Drilling(Snyder, 1998)

Surface

Casing

Depth

Seawater (E)hydrostaticpressure

Mud hydrostatic pressure (C) (Conventional)

Mud hydrostatic pressure (D) (Riserless)

Fracture (B)pressure

Pore pressure (A)

Pressure

Page 14: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

52TT01-43

Riserless Drilling System(Peterman, 1998)

Mud Returnand Pump

Return LineRiser

MudliftPump

BHA

Wellheadand BOP

Diverter

Drillpipe

Page 15: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

53TT01-43

Page 16: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

54TT01-43

“DGD is estimated to save $9 million per well and increase the

project value by $150 to $250 million at Crazy Horse”

Andy Frazelle, BP (Wellconnected, Dec, 2000)

Page 17: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

56TT01-43

“In an ultra-deepwater well, the savings could range from $5 - 15 million in casing running alone”

Conoco, 2001 (Drilling Contractor, May/June)

Page 18: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

57TT01-43

Mudlift System

(Conoco/Hydril)

Page 19: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

58TT01-43

Mudlift PumpingSystem

Page 20: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

59TT01-43

Mudlift Subsea Diaphragm Pumps

Page 21: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

60TT01-43

Mudlift Subfloor Module

Page 22: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

61TT01-43

Mudlift Subsea Diverter

Page 23: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

62TT01-43

Mudlift Drillstring Valve

Page 24: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

66TT01-43

(Baker Hughes/Transocean)

DEEPVISION System

Page 25: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

67TT01-43

Page 26: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

68TT01-43

DEEPVISION Subsea Centrifugal Pump

Pressure & volumecompensator

Strainer forcompensator

Isolation valves formotor filters

Main filters

Pump suction

Pump discharge

Electrical connections

Motor cooling loop

Filter for bearing pack

Isolation valves forBearing pack filters

6-Stage pump

Page 27: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

69TT01-43

DEEPVISION Subsea Module

5-pump module station Size: 15’ *17’ * 40’ Weight: 350 kips Max. available hhp 4050 ANSI 2500 (6250 psi)

rated Standard riser joint

connection Independent of BOP MUX

control system Self contained power and

control

10,000 ft. Pump Station

Page 28: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

71TT01-43

DEEPVISION Drillstring Valve

VALVE SEAT& CONE

VALVEPLUNGER

DISC SPRINGPACKAGE

4-3/4” Flow Stop Sub

Page 29: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

72TT01-43

DGD Rock Removal Rates

Drilling Rates (ft/hr)

Rock

Rem

oval R

ate

(to

ns/

hr)

100500 150 2000

4

8

12

12-1/4” Bit

Page 30: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

73TT01-43

Shell SSPS System

Page 31: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

74TT01-43

Shell SSPS DGD System(Offshore, June 2001)

Power Control Existing Rig PumpsFrom RigPower

Water Depth

Pump Section

Motor & Seal

6 - Pumps Total

NitrogenTank

Check Valve

Level SensorFor Process Control

EductorPump

ControlModule

Element OptionalFor Fluid Sep.

Mud Processing

Page 32: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

77TT01-43

SSPS Gumbo Slide & Mud/Gas Separation

Nitrogen Tank

(Back-up)

Mud/GasSeparator

Flowline

Subsea BOP

Cuttings

Eductor

GumboSlide

Nitrogen TankCut Away View

Page 33: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

80TT01-43

Dual Gradient Project Participation

CONOCO* HYDRIL* BP CHEVRON

MUDLIFTMUDLIFT TEXACO DIAMOND OFFSHORE GLOBAL MARINE SCHLUMBERGER

BAKER HUGHES* TRANSOCEAN SEDCO

FOREX*

DEEPVISIONDEEPVISION BP CHEVRON

SHELLSSPSSSPS

Page 34: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

85TT01-43

Hollow SphereDual Gradient System

Page 35: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

86TT01-43

Surface Hollow Sphere System

Riser

Mud Line

BHA

Wellheadand BOP

Drillpipe

Mud

Shale Shaker

Mud

Spheres

Spheres& Mud

Mud Pump(Spheres)

Mud Pump(Mud)

Swivel

Valve

Mud & Spheres

Drill Ship

Mud

Rock

Drill String Valve

Page 36: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

87TT01-43

Hollow Glass Sphere Technique

Mixture

Mud

Slurry

HollowGlass Spheres

Page 37: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

88TT01-43

New Seafloor Equipment

DeepVision Mudlift

Shell SSPS Maurer

Nothing

Page 38: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

89TT01-43

Sea Water Density Mud(50 % Spheres)

LIGHT WEIGHTMUDMUD HOLLOW SPHERES

8.56 ppg14 ppg 3.17 ppg1.02 S.G.1.68 S.G. 0.38 S.G.

Page 39: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

90TT01-43

4

6

8

10

12

14

16

18

0 20 30 40 70

Sphere Concentration (Volume %)

Mix

ture

Den

sity

, ppg

181614 12 10

Sphere Sp. Gr. = 0.38

Mud Weightppg

WaterSea Water

Mixture Density vs. Sphere Volume

10 50 60

Page 40: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

91TT01-43

Sea Floor

Fracture GradientPore Pressure

Safe Zone

10

12

1416

18

Mud weight (ppg)

Dual Gradient Mud Weights

Page 41: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

93TT01-43

Single Injection Point

Valve

Riser Flow Line

Mud& Spheres

Surface

Sea Floor

Mud& Spheres

Wellheadand BOP

Page 42: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

94TT01-43

Multiple Injection Points

10,000’

7,500’

5,000’

2,500’

Valve

Riser Flow Line

Sea Water& Spheres

Surface

Sea Floor

Page 43: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

99TT01-43

Surface Sphere Separation

ShaleShak

erSeawater

HollowSpheres

Drill CuttingsMud

Page 44: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

100TT01-43

Large and Small Hollow Glass Spheres

Page 45: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

101TT01-43

Particle Sizes in Unweighted, Water-Based Mud

(After Bourgoyne Jr. et al, 1986)

.01 0.1 1 10 100 1000 10,000

Drilled Solids

SILT FINESAND

COARSESAND

GRAVEL

200

100

60 20

MESH

Solid

s Pe

rcen

tag

e

MICRONS

LargeHollowSpheres

BentoniteSmallHollow

Spheres

Page 46: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

102TT01-43

Relative Particle Size (Microns)

50SmallHollow

Spheres

147100 Mesh

Screen

300LargeHollow

Spheres

1700FracSand

(12 mesh)

Page 47: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

104TT01-43

Composite Hollow Spheres

Page 48: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

106TT01-43

Composite Sphere Densities

WaterDepth (ft) PVC

ThermoplasticMacrospheres

GREMinispheres

Carbon FibreMinispheres

Foam System Density (g/cc)

100020003000400050006000700080009000

1000011000120001300015000

0.250.36

0.280.340.360.390.430.440.480.530.53

0.400.410.450.480.510.550.600.620.65

0.430.450.460.480.500.530.560.590.610.66

Page 49: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

107TT01-43

Riser Buoyancy Modules

Page 50: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

108TT01-43

Solids Separation

Page 51: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

109TT01-43

DGD Sphere Separation System 1100 1000

MESH

MICRONS

100 20

LargeSpheres

20 Mesh

Large CuttingsReturn Mud2000 gpm25% Spheres

Mud 1500 gpm

To Seafloor1000 gpm

50% Spheres

Clean Mud

ShaleShake

r

ShaleShake

rSpheres

Spheres500 gpm

Seawater

Medium Cuttings

Spheres500 gpm

100 Mesh

Spheres

ConventionalMud

System

To Rig Pump1000 gpm

No Spheres

500 gpm

Fine Cuttings

Spheres500 gpm

Mud1500 gpm

+

Page 52: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

110TT01-43

Hydrocyclone Separator

Barite (SG = 4.25)Drill Cuttings (SG = 2.65)

Hollow Spheres (SG = 0.4)Water (SG = 100)

Barite, Drill Cuttings

Mud & Spheres

Page 53: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

111TT01-43

100 1000

MESH

MICRONS

100 20

LargeSpheres

DGD Sphere Separation System 220 Mesh

Large CuttingsReturn Mud2000 gpm25% Spheres

Mud 1000 gpm

To Seafloor1000 gpm

50% Spheres

Clean Mud

ShaleShake

r

ShaleShake

r

Medium Cuttings(Few Spheres)

100 Mesh

ConventionalMud

System

To Rig Pump1000 gpm

No Spheres

CentrifugalPump

Spheres500 gpm

Mud 1000 gpm

Fine Cuttings

Mud500 gpm

+

SpecialHydrocyclone

Page 54: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

112TT01-43

Effect of Spheres on Plastic Viscosity

12.5 12.0

22.5

0

5

10

15

20

25

Pla

stic

Vis

cosi

ty (

cp)

No Spheres Large Spheres StandardSpheres

Water36% Spheres

Page 55: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

124TT01-43

Alternative Hollow Sphere

Injection Systems

Page 56: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

125TT01-43

Mud Line

Wellheadand BOP

Drillstring Injection DGD System

Riser

BHA

Drillpipe

Mud

Sphere Mixing Tank

Mud Pump(Mud)

Swivel

Mud & Spheres

Drill Ship

Mud

Rock

Casing

Sphere Separator

Page 57: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

126TT01-43

Drill String Sphere Separator

Sea Floor

Spheres

Spheres& Mud

Riser

SphereSeparator

Mud

Spheres& Mud

Casing Drill Bit

Drill Pipe

Page 58: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

128TT01-43

Carrier Fluid Dual Gradient System

Riser

Mud Line

BHA

Wellheadand BOP

Drillpipe

Mud

Shale Shaker

CarrierFluid

Spheres

Carrier Fluid& Spheres

Mud Pump(Spheres)

Mud Pump(Mud)

Swivel

Choke

Mud & Spheres

Drill Ship

Mud

Rock

InjectorPump Screen

Valve

Flow Controller

Page 59: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

129TT01-43

Mud

Injector Pump(Moineau)

Carrier FluidPlus Spheres

Screen

Return Line

Valve

CarrierFluid

Carrier Fluid Dual Gradient System

Mud

Choke

Page 60: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

131TT01-43

Seawater Transfer System

Mud

Seawater andSpheres

Seawater

Mud

Injector Pump(Moineau)

Mud andSpheres

Screen

Page 61: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

137TT01-43

Spreading Pore Pressure/Frac Curves Apart

Surface

Depth

Fracturepressure

Pore pressure

Pressure

Increased Frac Pressure

Seafloor

Flow Drilling

Page 62: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

140TT01-43

Curved Gradient Drilling

Page 63: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

141TT01-43

Fracture Gradient

Riser

Pore PressureGradient

Sea Floor

Conventional Deep Water Drilling

Safe Zone

Page 64: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

142TT01-43

Fracture Gradient

Riser

Pore PressureGradient

Sea Floor

Dual-Gradient Deep Water Drilling

Safe Zone

SubseaPumps

Page 65: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

143TT01-43

Fracture Gradient

Riser

Pore PressureGradient

Sea Floor

Curved-Gradient Deep Water Drilling

Safe Zone

Gas or SphereInjection Points

Page 66: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

144TT01-43

`

DRILLING FLUID

SPHERESOR GAS

PARASITE

INJECTIONPORT

Fluid Injection Techniques

GAS ORSPHERES

`

Concentric Drill Pipe Parasite String

Tie-Back Casing

SPHERESOR GAS

MUD

`

MUD

SPHERESOR GAS

Jet Sub

`

MUD

SPHERESOR GAS

Nozzle

Page 67: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

149TT01-43

Seafloor Sphere Injection0

6000

10000

15000

2000015,00010,0005,0000

Well D

ep

th (

ft)

Riser

Sea Water Density (8.6 ppg) (50%)

4470 psiSea Floor

11,750 psi

8110 psi

Annulus Pressure (psi)

Casing

Seafloor Sphere Injection

14 ppg (0%)

Page 68: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

150TT01-43

Sub Seafloor Sphere Injection0

6000

10000

15000

2000015,00010,0005,0000

Well D

ep

th (

ft)

Riser

10.4 ppg (33%)

Sea Floor

14 ppg (0%)

11,750 psi

8110 psi

Annulus Pressure (psi)

Casing

Sub Sea FloorSphere Injection

5410 psi4470 psi

Page 69: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

151TT01-43

Sub Seafloor Sphere Injection0

6000

10000

15000

2000015,00010,0005,0000

Well D

ep

th (

ft)

Riser

11.3 ppg (25%)

Sea Floor

14 ppg (0%)

11,750 psi

8110 psi

Annulus Pressure (psi)

Casing

Sub Sea FloorSphere Injection

5876 psi4470 psi

Page 70: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

153TT01-43

Lightweight Brine Drilling Fluid

Sea Water(8.56 ppg)

Salt Brine(12 ppg)

Salt Brine + 39% Spheres(8.56 ppg)

Page 71: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

155TT01-43

Major Questions

• Will Hollow Spheres Survive?

• Can Spheres Be Pumped Reliably?

• Can Spheres Be Separated From Mud?

• Can Sphere Circulation Be Initiated after Shutdowns?

• Maximum Sphere Concentration Achievable?

• How to Detect and Handle Kicks?

• Can Constant Seafloor Pressure Be Maintained?

• System Cost and Reliability?

Page 72: A Noble Drilling Corporation Subsidiary TT01-431 Hollow Sphere Dual Gradient Drilling System JIP Kickoff Meeting Dr. William C. Maurer September 27, 2001.

164TT01-43