dual gradient drilling: has its time finally come?cargos-paquebots.net/revue de...
TRANSCRIPT
![Page 1: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/1.jpg)
© Chevron 2005 20090422, AADE Emerging Technologies Forum
Dual Gradient Drilling:
Has Its Time Finally Come?
AADE Emerging Technologies Forum
Ken Smith
Chevron Deepwater BU Project Manager, Dual Gradient Drilling Implementation
April 22, 2009
![Page 2: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/2.jpg)
2© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Key Messages
• Deepwater Gulf of Mexico drilling is extraordinarily challenging
• Dual gradient drilling is the solution to the water depth-related challenges, and
• The Managed Pressure Drilling capabilities of the technology can solves a number of downhole problems related to annular pressure changes.
• What is DGD and why does it work?
• It’s been done before.
• We’re considering it again!
![Page 3: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/3.jpg)
3© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Deepwater Gulf of Mexico Situation Today
We routinely drill nearly “un-drillable”wells
>30,000’ deep
> 6,000’ water depth
> 9,000 MRI’s
Narrowing of the PP/FG window and ECD’s lead to MANY tight tolerance casings
New rigs capable of drilling to 40,000’ to enable industry’s large portfolio of deepwater projects
We’re just about against “The Wall”
Conventional Casing Program
Deepwater Casing Program
We’re nostalgic for the past!
![Page 4: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/4.jpg)
4© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 4
The Solution
Dual Gradient Drilling is a Form of Managed Pressure Drilling
It Removes the Impact of Water Depth
![Page 5: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/5.jpg)
5© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
1996 through
2001
1996 1996 through through
20012001
![Page 6: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/6.jpg)
6© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Single vs. Dual-Gradient Drilling
Dual Gradient
Heavier Mud w/ Seawater Above
Mudline
Same Bottom Hole
Pressure
SingleMud
Weight
Conventional
![Page 7: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/7.jpg)
7© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 7
Seabed
SeawaterHydrostatic
Depth
Dual Gradient MudHydrostatic
Conventional Mud Hydrostatic
RKB
Why Does It Work?
Pressure, psi
Density
![Page 8: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/8.jpg)
8© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 8
Seawater Hydrostatic
Single Gradient Density at TD
Casing Points – Conventional
Seafloor
Depth
Pressure
Fracture Pressure
5 Casing Points
TDPore Pressure
![Page 9: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/9.jpg)
9© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 9
Fracture Pressure
Seawater Hydrostatic
Casing Points – Dual Gradient
Seafloor
Depth
Dual Gradient Density at TD
Pressure
TD
4 Casing Points
Pore Pressure
![Page 10: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/10.jpg)
10© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Fracture Pressure
Seawater Hydrostatic
Seafloor
Depth
Casing Points – Dual Gradient
Pore Pressure
Pressure
3 Casing Points
10
TD
Dual Gradient Density at TD
![Page 11: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/11.jpg)
11© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Application of Dual Gradient Drilling: Potential for Elimination of Casing Strings in Complex Wells
Potential Well Planwith DGD Application
Actual Casing Program
6 casing strings (yellow) potentially could have been eliminated had DGD technology been available
![Page 12: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/12.jpg)
12© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Simplified Well Design Allows More Completion Opportunities
Simplified Well Design Allows More Completion Opportunities
13-3/8
(Conventional)5-1/2"
Tubing
36 3626 20
(SubSea MudLift)
9-5/8
7-5/8
7" Tubing
5-1/2
11-3/4
9-5/8
22
16
13-3/8
SWF Zone
![Page 13: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/13.jpg)
13© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
How Will DGD Improve the Deepwater Business?
ENHANCE SAFETY AND ENVIRONMENTAL PERFORMANCE AND RISK
• Much better detection, reaction and control of kicks, which WILL be smaller
• Inherently safer wells
• Better environmental footprint
REDUCE DRILLING COST AND RISK
• Fewer strings of casing to reach TD
• Virtual elimination of lost circulation due to ballooning formations
• Significant reduction in “hidden downtime”
• Better cement jobs/fewer squeezes
IMPROVE WELL INTEGRITY
• Reduced casing loads
• Greater completion integrity
IMPROVE WELL PRODUCTIVITY
• Designer completions will become possible
IMPROVE EXPLORATION PERFORMANCE
• Easier geological sidetracks
• More effective reaction to formation “surprises”
IMPROVE PREDICTABILITY
• Improved reliability/reduced downtime, leading to
• More predictable outcomes
• Lower $/BOE Cost• Lower Minimum Economic Field Size
![Page 14: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/14.jpg)
14© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 14
MudLift Pump (MLP)
Mud Return Line
Drill String Valve (DSV)
SubSea MudLift Drilling Defined Major Components
Subsea Rotating Device (SRD)
![Page 15: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/15.jpg)
15© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 15
The Hydril MudLift Pump is Driven by Seawater
Displacing Mud to Rig
Seawater Pumped from RigSeawater Discharged to Sea
Mud Enters From Well
![Page 16: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/16.jpg)
16© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 16
Test System Pumped for Nearly 2 Years
![Page 17: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/17.jpg)
17© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 17
Solids Pumping Capabilities
![Page 18: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/18.jpg)
18© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 18
Drill String Valve (DSV ) was Tested for LCM and MWD Signal Throughput
![Page 19: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/19.jpg)
19© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 19
Subsea Rotating Device Testing
SRD HousingSRD Housing
Stripper Element TestingStripper Element Testing
Purpose: Provide a mechanical interface between the drilling mud in the well and the seawater in the riser. Also minimizes gas ingress to the riser. Insert below retrieves on drill string every trip.
![Page 20: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/20.jpg)
20© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 20
Factory Acceptance Testing Began Feb 28, 2001
![Page 21: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/21.jpg)
21© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 21
Test Well Drilled in Aug/Sept, 2001
Diamond OffshoreOcean New Era
2nd Generation,Built in 1975
Texaco WellGC 136 #8
Shasta Prospect
![Page 22: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/22.jpg)
22© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 22
Driller’s Subsea Controls
![Page 23: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/23.jpg)
23© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 23
Control / Monitoring Screens
![Page 24: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/24.jpg)
24© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Equipment is Only Half the Challenge
![Page 25: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/25.jpg)
25© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 25
12 to 15 Man-Years Required to Develop DGD Operations and Well Control Procedures
Drilling Operations Unchanged Changedw/SMD Test
1. Circulation
2. Drilling ahead
3. Connections
4. Tripping
5. Displacing drilling fluids
6. Lost circulation treatment
7. Wireline logging
8. Running casing
9. Running liner
10. Cementing casing
11. Cementing liner
12. Balanced plug
13. High pressure squeeze
14. Stuck pipe procedures
15. Use and installation of packers
![Page 26: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/26.jpg)
26© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 26
ALL Well Control Operations Change
Well Control Operations Unchanged Changedw/SMD Test
1. Kick detection2. Basic well control with DSV
(Driller's Kill)3. Basic well control w/o DSV: NO
shut-in4. Basic well control w/o DSV: WITH
shut-in5. Kick detection during tripping
6. Shut-in while tripping
7. Trapped pressure management
8. Volumetric well control
9. Lubrication kill
10. Stripping
11. Bullheading
12. Shut-in while running casing
13. Test casing seat
14. Dynamic kill
![Page 27: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/27.jpg)
27© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
SMD Drilling Simulator
27
![Page 28: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/28.jpg)
28© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 28
Training Materials and Process
Basic SMD Training (DGD)
Pre-Spud Materials
Drilling Program
Procedures Training
Well Control Training
![Page 29: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/29.jpg)
29© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Training Matrix
Advanced A
Intermediate I
Basic B
Position Wel
l Des
ign
Wel
l Con
trol
Wel
l Ope
ratio
ns
Rig
Ope
ratio
ns
Equi
pmen
t Mai
nten
ance
Position Wel
l Des
ign
Wel
l Con
trol
Wel
l Ope
ratio
ns
Rig
Ope
ratio
ns
Equi
pmen
t Mai
nten
ance
Operator OthersDrilling Manager I I I B Subsea Engineer I I A ADrilling Superintendent I I I B B Mudlogger I B BDrilling Engineer A A A B B Mud Engineer I I I IRig Supervisor I A A A I Cementer B B B B
Hydril Personnel B B B ADrilling Contractor Regulatory Agencies B A B I IRig Manager A I I I I DGD Consultant A A A A AToolpusher I A A A A Partners I I I I BDrilling Engineer I A A A ADriller I I A AAssistant Driller B B A ARig Mechanic I ADerrickhand B B B BFloorhand B B B
Training LevelsComprehensive understanding of all facets of DGD; ability to formulate, design and communicate DGD procedures and techniquesWorking understand of DGD concepts and relational impacts to drilling operations; ability to use knowledge to make real-time decisions regarding well and equipmentPractical understanding of DGD as related to his/her job functions
![Page 30: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/30.jpg)
30© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 30
Pre-spud and Training Included Rig Crews, Service Personnel, MMS, Operator Representatives
and Engineers
![Page 31: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/31.jpg)
31© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Hoisting the MLP Through the Moonpool
![Page 32: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/32.jpg)
32© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 32
Driller’s Main Panel
![Page 33: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/33.jpg)
33© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Moving in BOP
![Page 34: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/34.jpg)
34© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Landing SMD/ LMRP on BOP Landing SMD/ LMRP on BOP
![Page 35: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/35.jpg)
35© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 35
Heading Down with the MLP
![Page 36: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/36.jpg)
36© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Field Test SMD System and Riser
•Auxiliary Lines on riser
![Page 37: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/37.jpg)
37© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
Running Mud Line
![Page 38: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/38.jpg)
38© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 38
Gumbo Drilling
Gumbo Dogs
![Page 39: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/39.jpg)
39© Chevron 1/2008 20090422, AADE Emerging Technologies Forum 39
All Important Objectives Met
• Manage Bottom Hole Pressure at All Times
Constant inlet pressure mode (Drill)
Constant rate mode ( Kick or Kill)
• Cuttings to Surface
• Verify Dual Gradient Operation Procedures
• “Kick” detected/shut-in <2 bbls
• All Equipment Operated as Designed
• Personnel adapted quickly, training paid off
• 90% of Field Test Objectives met
![Page 40: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/40.jpg)
40© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
![Page 41: Dual Gradient Drilling: Has Its Time Finally Come?cargos-paquebots.net/Revue de presse/0000_IMAGES-05/524...Advanced A Intermediate I Basic B Position Well Design Well Control Well](https://reader030.vdocuments.mx/reader030/viewer/2022021506/5b03e5c37f8b9a6c0b8cfbb6/html5/thumbnails/41.jpg)
41© Chevron 1/2008 20090422, AADE Emerging Technologies Forum
The Clear Leader