Case Study – Reducing Drilling hours by up to
54% in the Barnett Shale Douglas Gust P.Eng., Q’Max Solutions Inc.
Scott Marquess, Q’Max Solutions Inc.
Lane Dunham, Savanna Drilling USA
March 31, 2009
2
Barnett Shale Drilling Optimization Project
• Introduction• Project Scope• Achievements• Conclusions
3
Project Overview
• GOAL – Reduce well construction cost - $/ft
• Scope of Project– Build on what others had done – bits/directional etc.– Optimization of Drilling Fluid
• “Solids Free Drilling Fluid” – “SFDF”• Solids Control• Waste Management
– Reduction of hole sizes– “New Technology Drilling Rigs” – NTDRs
• Time Frame– 20 month project 3Q 2006 to 1Q 2008
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SFDF
• Solids Free <1% suspended solids• Density up to 10.5 ppg in solution
– Typically 8.8 – 9.5 ppg – averaged 9.2 ppg on this project
• Inhibitive– Used Calcium Nitrate or Production Brine
• Easily converted to Polymer fluid when necessary– Well control – densities > 10.5 ppg
• Low rheology – Low ECD– Viscosity = 28 to 31– YP = 1 to 3
• 100% reusable
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Solids Control – MudStripper™
Designed for SFDF• Remove 99.5% drill solids• Footprint = 15’ x 60’• Operates as “Closed Loop”• Sludge density range:
– 14.5 to 17.5 ppg
Shaker Cuttings MudStripper™
Sludge
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Cuttings Handling
Old Style Pit150’ x 100’ x 6’
14,000 bbls
Sludge Pit30’ x 12’ x 8’
500 bbls
Auger Tank Solids collection / Dump truck disposal
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Well Construction
• Hole size Reduction– Surface hole
• Reduced from 12 ¼” to 8 ¾”
• Reduced Casing from 9 5/8” to 7”
– Main Hole• Reduced from
7 7/8 – 8 ¾” to 6 1/8”• Reduced Casing from
7” to 4 ½”
• Benefits– Reduced cuttings volume– Reduced cement volume– Lower cost casing– Increased casing
availability
• Concerns– ROP– Tool Reliability– Cement quality
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NTDR
NTDR – “New Technology Drilling Rig”
• Integrated top drive / pipe handling system– Some rigs drill with coil
tubing
• Small footprint• Fast moving (12
to 15 loads)
Benefits• Safety – reduced
risk for crews• Improved ROP
– Drill with Coil• No connections
– Drill with Range 3 pipe
• Smaller location sizes
• Fast Rig up/Tear down
• Shorter move times
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Accomplishments
• 41% reduction in average Drilling Hours– 226 hours/well to 133 hours/well
• 41% reduction in average Well Days– 20 days/well to 12.5 days/well
• 83% reduction in average Fluid Volume– 10,000 bbls/well to 1,729 bbls/well
• 100% reduction in Dilution Volume– Dilution was eliminated
• 75% reduction in surface area of drilling site– 400 ft x 400 ft to 200 ft x 200 ft
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Average Drilling Hours
• Project Start– 226 hours/well
• Conventional Rig – 44 wells– 155 hours/well
• NTDR – 96 wells– 123 hours/well
• Best 2 rigs – 34 wells– 103 hours/well
• One NTDR w/ & w/o SFDF– 31 wells w/SFDF
• 131 hours/well
– 7 wells w/o SFDF• 153 hours/well
Average Drilling Hours
0
50
100
150
200
250
ProjectStart
ConvRig
NTDR Best 2Rigs
Dri
llin
g H
ou
rs
SFDF
NTDR Drilling Hours (31 wells with SFDF & 7 wells w/o SFDF)
120
125
130
135
140
145
150
155
Non SFDF SFDF
Dri
llin
g H
ou
rs
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Average Days / Well
• Project Start 20 days/well
• 157 wells 12.5 days/well
• SFDF– 149 wells
11.9 days/well– 97 wells NTDR
10.5 days/well– 77% of wells
< 15 days
Number of Wells by Days
0
2
4
6
8
10
12
14
16
5 10 15 20 25 30 35Well Days
Num
ber of
Wel
ls
NTDR SFDF
Conv Rig SFDF
NTDR w/o SFDF
Conv Rig w/o SFDF
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Average Drilling Performance
• Average Performance based upon “well days”670 ft/day
• SFDF700 ft/day
• Best 2 Rigs848 ft/day
NOTE: Op #2 calculated from assumed 10,000 ft well depth and days from Spud to TD
Drilling Performance in the Barnett Shale
0
100
200
300
400
500
600
700
800
900
2005 2006 2007 2005 2006 2007 2007 2007 2006 2007 2006 2007 2007
Drilli
ng P
erfo
rman
ce (ft/d
ay)
Op #1 Well days
Op #2Spud to TD
Op #3 This ProjectWell days
SFDF Best 2 rigs
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Drilling Performance by Bit Diameter
Bit Diamete
r (in)
# wells
Average Drilling
Performance (ft/day)
SFDF
6 1/8” to
6 ¾”125 692 719
7 7/8” to
8 ¾”32 577 613
157 670 700
Drilling Performance
0
100
200
300
400
500
600
700
800
6 1/ 8 to 6 3/ 4 7 7/ 8 to 8 3/ 4Main Hole Diameter (in)
Drilli
ng P
erfo
rman
ce (ft/d
ay)
Non-SFDF SFDF
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Fluid Volume Reduction
• SFDF & MudStripper™ is a “Closed Loop” system
• SFDF is 100% reusable
• Reduced hole sizes reduces volumes– Seepage loss– Fluid on
cuttings
1,729 bbls8,000 bbls
1,000 bbls
2,000 bbls
5,000 bbls
Average Volume Used / well Change in Hole SizeElimination of Dilution Elimination of Sump
Fluid Volume Reduction
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Reduced Location Size
• Location reduced from 400’ x 400’ to 200’ x 200’– 75% reduction in surface
area
• NTDR– Small footprint
• MudStripper™– “Closed Loop” system
with small footprint0
50
100
150
200
250
300
350
400
0 50 100 150 200 250 300 350 400
Original Location Size400 ft x 400 ft
Reduced Location Size200 ft x 200 ft
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Conclusion
• KEY Success Factors– Project Integration & Execution– SFDF– NTDR– Hole Size Reduction
• Significant reduction in $/ft achieved– Some individual costs (product and services)
increased– Variable cost – time related decreased– Some costs (casing) decreased
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Conclusion – Project Milestones
2.3 % average suspended solids (<1% typical)
4.6 days – Spud to TD on fastest well (8,400 ft)
6 1/8 inch bit used to drill main hole (97 wells)
7 “one bit” runs from surface casing to TD
8 counties in project
11.9 days/well average using SFDF (149 wells)
31 wells with average footage > 1,000 ft/day
157 wells in the dataset
700 ft/day average with SFDF
1,729 bbls/well average fluid volume
4,240ft – most footage drilled in one 24 hour period
