Successful Application of Innovative
Reaming-While-Drilling Technology
in Williston Basin Wells
Presenters
Lee M. Smith - Greg Scott
Western Energy Products and Services
The Challenge
– Challenge – eliminate dedicated reamer run in
Bakken wells; ream-while-drilling (RWD)
application
– Introduction of 5 7/8” OD PDC reamer for use in
6” lateral section: non-mag and steel body tools
– Successful installation of multiple swellable
packers – up to 40 per well
– Significant savings per well (up to 3 days rig time)
Geology
Williston Basin Bakken
• Oil reservoir, dolomite
layered between two
shales
• Produces oil, gas and
natural gas liquids
• Depths from 8,000 to
10,000 ft
• Lower shale, middle
sandstone and upper
shale
• Middle sandstone varies
in thickness, lithology
Hazards of Bakken
• 30+ formations
from surface to
target
• Potential aquifers
• Sticking salt,
bentonite beds
• Sloughing shales
• Known H2S
Williston Basin Well Design
• 8 ¾-inch vertical hole
section to KOP in
target formation at
9,000’ to 10,000’ TVD
• 8 ¾” inch hole builds
angle to horizontal in
Bakken at around
11,000’ TVD
• Lateral up to 10000’
• 20,000’ MD @TD
• Multiple swell
packers to TD
An Innovative Solution
Incorporate PDC Reamer to
drill/ream in 6” hole
– Eliminates need for
dedicated reamer run
– Delivers high quality
wellbore for multiple
packer completion
PDC Reamer Tool Delivery to Isolated
Rig Location
Introduction to PDC Reamer
Un-aware of PDC Reamer Advantages
Not using
PDC Reamer
Concerned about PDC Reamer
Reliability
- Review PDC Reamer reliability features
-Review Run Histories and Customer Testimonials
Thinks PDC Reamer is good but costs
more than conventional stabs
- Discuss PDC Reamer advantages compared to stabs
-Explain durability features of PDC Reamer
-Show Savings Case Histories
Why
Customer
Using PDC
Reamer
-Reamer functionality compared to stabilization alone
-Reamer reliability proven in multiple applications
-Reamer advantages over use of stabilizers alone
-Reamer design advantages for added durability
- Design features for greater reliability, durability
Yes
-Review PDC Reamer reliability features
-Run Histories and complete re-design
No
-Explain durability features of PDC Reamer
-Discuss PDC Reamer application features
-Stress Run Histories and Customer Testimonials
Experienced
Lost Cutters ?
Introduction to Drilling Tools
PDC Reaming Tool– Customer Approach
•
A PDC Reamer is fit for any application that is expected to face
stuck pipe problems
•
Key words that trigger a need for a PDC Reamer are:











Heavy back reaming
Mobile or transient formation
Moderate fractured and faulted formation
Swelling shales
Salt layers and salt domes
Unconsolidated formations
Tight spots
Key seats
Poor hole cleaning
Inter-bedded formations or hard stringers
NPT during POOH
PDC Reamer Tool
Reamer with drilling
functionality
•
•
•
Reduce back reaming time
Removal of Irregularities for
smoother POOH
Better hole quality
Removes hole irregularities by:
•
•
Scraping
Cutting (Shearing)
Dual cutting mode ideal for
transition drilling
PDC Reamer Features
PDC cutters on leading edges of
blades :
•
Allow re-opening holes to avoid
having stuck pipe during POOH
•
Reduce torque and drag in highly
irregular holes
•
Improve hole gauge and shape by
removing ledges and irregularities
•
Allow opening key-seats & ledges
•
Acts as backup hole opener when
bit gets under-gauge
•
Cutter design and distribution to
match application severity
Design Advantages
• Use of stud cutters to
introduce in-string drilling
• Blade design provides
proper cutter support to
eliminate cutter shear
• Blade design ensures 360
degree coverage
• Hydraulic profile
optimizes mud flow and
resists balling
Impact on Performance
•
•
•
Balanced cutting structure
with cutter redundancies
ensures optimized cutting
and long life
Reaming inserts arranged
to provide continuous
reaming and outstanding
hole quality
Reamed volume matched
to tool life for uniform tool
wear
Cutting
Elements
Scraping
Elements
Drill / Ream Parameters
– Multiple RWD BHA designs incorporating both non-mag
steel body PDC Reamer tools
– Test steerability, torque and successful installation swell
packers
– Compare RWD BHA to previous lateral BHA – slick and
stabilized
– Results / findings – torque increase from 7 to 13 with 20%
increase in rotary ROP
– Optimal RWD BHA – 30ft spacing between PDC reamers
positioned on top of lower BHA using steel body tools; 30ft
spacing between PDC reamers in lower BHA using nonmag tools
– Able to drill out 7” casing shoe
Introduction to Drilling Tools
PDC Reaming Tool – Introduction and Background
•
Well profiles are becoming more complex and access to reservoir
intervals is becoming more challenging
•
New drilling technology and methodology:

Multi-lateral wells

Deep horizontal wells

Extended reach drilling

High Pressure High temperature wells

High Angled J-Profile ; S-Shaped wells
•
It is critical to optimize drilling efficiency and reduce Non-Productive
Time (NPT)
•
A PDC Drilling Tool is a tool that reduces the hazards of having stuck pipe;
a feature that significantly reduces NPT
Introduction to Drilling Tools
PDC Reaming Tool – Operations Concept
Cutting
Elements
•
•
A PDC Reaming Tool is a reamer with drilling
Scraping
functionality
Elements
The design intent is to:
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
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•
Traditional Reamer removes hole irregularities by:

•
Scraping
Tool removes hole irregularities by:


•
Reduce back reaming time
Removal of Irregularities for smoother POOH
Better hole quality
Scraping
Cutting (Shearing)
Cutting mode renders this tool unique when dealing with holes
with excessive irregularities (transient formations)
Introduction to Drilling Tools
PDC Reaming Tool – Main Functions
Blades leading edges doped with PDC cutters to:
•
Allow re-opening holes to avoid having stuck pipe during POOH
•
Reduces torque and drag whilst in reaming in highly irregular holes
•
Improve hole gauge and shape by removing ledges and irregularities
•
Allows opening key-seats & ledges
•
Acts as backup hole opener when bit gets under-gauge (Dual action tool)
•
Cutter matrix design and reaming insert distribution can be varied to
match application severity
Introduction to Drilling Tools
PDC Reaming Tool – Main Functions
Mobile Formations
Hole Cleaning
Moderate Fractured &
Faulted Formations
Unconsolidated
Formations
Reactive Formations
Key Seating
Over-Pressured
Formations
Ledges and Doglegs
Introduction to Drilling Tools
PDC Reaming Tool - Construction
Tool design addresses several design
intents and utilizes several features
•For drilling:


Tool utilizes the use of stud cutters to
introduce in-string drilling
Tool blade design solves the problem of stud
cutters shear through proper cutter support
Introduction to Drilling Tools
PDC Reaming Tool - Construction
•
For stability:
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•
Spiral Blade design ensures 360 degree coverage
For hydraulics:

Mud way profile optimizes mud flow and resists balling
Blade 360 Coverage
Introduction to Drilling Tools
PDC Reaming Tools - Construction
For performance:
•
Balanced cutting structure with cutter redundancies ensures optimized cutting
and long life
•
Reaming inserts arranged to provide continuous reaming and outstanding hole
quality
•
Reamed volume matched to tool life for uniform tool wear
Cutter Pairs
Backup Gage
Cutters
Introduction to Drilling Tools
PDC Reaming Tool - Construction
•
For productivity:

•
Design process is automated,
this allows for fast
customization
For manufacturing:


Stud cutters allow the use of
traditional 4 axis milling
Tool configurations of same
size use same turning profile
(for inventory)
Introduction to Drilling Tools
PDC Reaming Tool - Models
Single Action Tool
Fishing side doped
with PDC cutters
Optimized TCI
distribution on gauge
part
Down-hole side covered
with reaming TCI inserts
Full coverage spiral
Dual Action Tool
Fishing side doped
with PDC cutters
Optimized TCI
distribution on gauge
part
Down-hole side doped
with PDC cutters
Introduction to Drilling Tools
PDC Reaming Tool - Models
6 Blade Tool
Larger Mud Way
Cross section and
more TFA than a 6
Blade
Same reaming capacity as a 6
Blade Tool
Longer tool and longer crown length
Same number of cutters as a
6 Blade Tool
Introduction to Drilling Tools
PDC Reaming Tool - Features
Chamfered blade for proper
PDC cooling and cleaning
Oriented stud cutters for
optimum cutting
Upper cutter set opens from
neck to hole gauge
360 Blade coverage
Omni Axi-symmetric
cutter distribution for
balanced drilling &
reduced vibrations
cutter design
Cutters deeply inserted
in blade for elimination
of shear plane
OMNI mud-ways,
optimized to minimize
balling potential
OMNI TCI distribution,
optimized for uniformity of
reamed surface and balanced
insert wear
Lower cutter set opens
from bit under gauge to
hole gauge
Subject Well #1
• BHA : PDC reamer above 5
¼” 6/7 motor with 1.5
bend; UBHO; 2 x NMDC;
PDC reamer
• Begin reaming lateral
10,500’
• Flow rate =205 GPM
• 65 RPM surface rotary +165
RPM at motor for 230 RPM
Well #1 Re-Cap
• 32 hours reaming, 9000’ feet open hole, on
bottom drilling at 19,495’ depth
• Average 25 ft/hr in rotary mode and 12 ft/hr
sliding mode
• Rig limited to 4250 psi differential; difficulty with
second slide in getting required high side tool
face
• Planned, 10-20 stand short trip
• Reamed the last 800’ to TD at 20,232’
• BHA POOH and 21 swell packers successfully run
Subject Well #2
• BHA : 6-inch PDC bit; 4-3/4” 7/8 fixed
housing motor with 1.5 bend; 5 7/8-inch
NM PDC reamer; UBHO; NMDC; NM PDC
reamer
• Ream lateral hole from 10,500’ to 15,552’
• Ream-while-drilling from 15,552’ to TD at
19,576’
Well #2 Re-Cap
• Run in to ream at 5000’ to bottom,
holding angle over 4024 feet
• RWD from 15,552’to TD at 19,576’
• 5.14% sliding in 24.5 hrs
• 94.86% rotating with 49.58 rotary hrs
• Rotating ROP of 77 ft/hr over 3817
feet
• Sliding ROP of 9 ft/hr over 207’
• Eliminated dedicated reamer run
• 21 swell packers successfully
installed
Subject Well #3
• BHA : 6-inch PDC bit; 5” 4/5 fixed housing
motor with 1.5 bend; UBHO; NMDC - 2;
XO; steel PDC reamer; HWDP – 1; steel
PDC reamer
• Drill out 7” shoe with RWD BHA
• Ream-while-drilling from 10,320’ to TD at
19,820’
Well #3 Re-Cap
• P/U RWD BHA and drill out 7” casing
shoe
• RWD from 10,320’ to TD at 19,820’
• 9.2% sliding in 10 hrs
• 90.8% rotating with 98 rotary hrs
• Rotating ROP of 88 ft/hr over 9000
feet
• Sliding ROP of 35 ft/hr over 350’
• Eliminated dedicated reamer run
• 30 swell packers successfully
installed
Ream-While-Drilling BHA Design
• Optimal RWD BHA
– 30-foot spacing between PDC reamers positioned on
top of the lower BHA using steel body tools
– 30-foot spacing between PDC reamers in the lower
BHA using non-mag tools
RWD BHA concerns:
– 60-foot spacing between PDC reamers had a dropping
tendency in rotary
– PDC reamers run without any spacing created to stiff
an assembly and was difficult to steer/orient while
sliding.
‘Best Practice’ RWD
– Surface handling PDC reamers: Care should be taken
in picking up and laying down of reamer tools to
insure no surface breaking / chipping of the PDC
cutters and TCI
– When reaming back to bottom with PDC reamers in
the lateral drilling BHA, it is recommended to ream at
250-300ft/hr due to the 1.5 degree bend in the motor
– PDC reamers are only effective while in the rotary
mode so it is necessary to ream or back ream each
slide interval to insure a smooth well bore.
Conclusions: Use of PDC Reamer
– 100% successful swellable packer installations
– No issues with steerability
– Increase in rotary ROP – smooth well bore, greater
on bottom WOB
– Low / manageable torque
– Versatile RWD BHA using both non-mag and steel
body PDC reamer tools
– Eliminated dedicated reamer run
– 3 days rig time savings per well
Rockin’ (reaming) in the Bakken
• Innovative solution using PDC
Reamer proven in multiple wells
– Reamed in excess 750,000’ of
hole / over 50 wells in ND/MT
– Eliminates need for dedicated
reamer run
– Saves average of 3 days/well
– $225K savings per well
– Established ‘best practice’ for
Williston Basin wells
Acknowledgments
• This new technology, through the combined efforts of proven North
Dakota operations groups, rig and service companies, has eliminated the
dedicated reamer run at TD while delivering good wellbore condition that
enables multiple swellable packers to be run in a single, fast trip. We have
worked with a number of operators , drilling contractors and service
contractors – we appreciate their support in moving this project forward.
• Additionally we would like to thank our TERCEL manufacturing plant for
their support on this project Omar Ahmed, Duane Shotwell and Michael
Byerley . We as also would like to thank our WEPS / AER field service
personnel William Collins , Mitchell Fenske and Alicia Kerr.