This technical presentation provides an overview of horizontal directional drilling (HDD) technology and how it can help develop secure pipeline infrastructure in Nigeria. HDD involves drilling a pilot hole underground at a slight angle and enlarging the hole to pull pipelines through, allowing for land/water/road crossings with minimal environmental impact. The presentation outlines factors affecting pipeline development in Nigeria, HDD applications, procedures like site preparation and pullback, required equipment, and benefits like protection from damage. HDD can help address challenges like vandalization through deep burial of pipelines.

1. A TECHNICAL PRESENTATION
HORIZONTAL DIRECTIONAL
DRILLING (HDD) TECHNOLOGY
GEORGE UDEMEOBONG NTA
0803 512 8478
BY
ON

2. Objective
• To enlighten the audience on Horizontal
Directional Drilling Technology and how it
can contribute towards developing and
securing effective pipeline infrastructure in
Nigeria.

3. Some of the Factors affecting development and
security of Pipeline Infrastructure in Nigeria
• Technology
• Technical Expertise
• Finance
• Vandalization
• Comprehensive Pipeline Infrastructure
Database
• Government and Regulatory Authorities
• Social Awareness

4. Horizontal Directional Drilling Technology
Overview
• Developed in the early 70’s
• Combination of road boring and oil well
directional drilling
• Lengths up to 3900m
• Pipelines up to 56 inch. Diameter
• Installation through sand, silts, clays
and rock

5. Directional Drilling Applications
• Land to Land Crossing
– Rail, Road and River Crossings
– Contaminated and environmentally significant areas

6. Directional Drilling Applications
Water to Water
crossing Islands
crossings Channel
Land to water crossing
Shore approaches
Outfalls

7. PROCEDURE FOR HDD
• INITIAL PLANNING / FEASIBILITY
• GEOTECHNICAL REVIEW
• ENGINEERING DESIGN
• INSTALLATION PROCEDURE
• PULL BACK
• DEMOBILISATION

8. INITIAL PLANNING/ FEASIBILITY
• Site Investigation
• Preliminary Design
• Construction Costs
• Time scale: - engineering &
preparations 3 months, drill hole 2
weeks, pull back 1 day.

9. Directional Drilling Installation Procedure
• Mobilization and Site Preparation
• Pre-HDD Activities Installation Procedure
• Rig-up
• Temporary Casing Installation (If required)
• Pilot Hole
• Hole Opening Pass
• Pullback
• De-Mobilization

10. Site Preparation
• Two sites normally required
• Rig site 50m x 50m
• Pipe side and stringing site
• Staged on land and offshore

11. Typical Drilling Rig Site

12. Pilot Hole Assembly
• Jetting or rock bit
• Non-magnetic collars
• Survey tool
• Non-magnetic collars

13. DRILL BIT TYPE
Mill-tooth Cutter TCI - Cutter

14. PILOT HOLE PASS
• Installation of Para-track Guidance System
• Typical Sizes
– 8.5” (216 mm) – 12.25” (311.2 mm)
• Drill Path Design
– Entry Angles: 10 – 18 degrees
– Design Vertical Curves: 100 x Outside Diameter
(100 x 12) = 1200’ (366 m)
– Exit Angles: 6 – 10 degrees. Subject to final
design calculations.

15. Drilling Fluids
• Purpose
– Cutting medium for jet bits
– Drive mud motors
– To suspend carry cuttings away from face of drill and out of
drilled bore
– Provide fill to stabilize bore
• Basic Materials
– Dry Bentonite (naturally occurring clay)
– Fresh water

16. REAMING-HOLE EXPANSION

17. FLY CUTTERS & BARREL
REAMERS
BARREL REAMERS
FLY CUTTER

18. CONVENTIONAL HOLE OPENERS – MILL
TOOTH CUTTERS

19. PULLBACK
• Swab Pass(es)
• Connection to Carrier Pipe
• Rate of Pull
• Buoyancy Control

21. TYPICAL PIPELINE
PULLBACK

22. ENTRY POINT PULLBACK

23. Project Principles
• To assess the feasibility of a HDD project
the following basic information is required.
 Environmental Considerations
 Logistics
 Topography
 Geology

24. Project Principles
• Environmental
Disturbance to the local
environment from Drilling
Operations.
Drilling Fluid discharge
risks, control and mitigation.
• Logistics
 Transport of Equipment.
 Support for Drilling
Operations.
 Movement of Tools.
 Disposal of Cuttings and
Drilling Fluids.
 Movement of Personnel

25. Project Principles
• Topography
– Location Plan
– Area Plan
– Longitudinal Section
including levels
– Depth of Steams and
Rivers
• Geology
– Evaluation of Existing
Documentation
– Historical Research
– Boreholes
– Penetration Tests
– Geophysical Tests
– Laboratory Tests
– Geotechnical Reports

26. GEOTECHNICAL REVIEW
• Number / Depth of Borings
• Sieve Analysis Tests
• Unconfined Compressive Strength
Tests
• Rock Quality Designation (RQD)

27. ENGINEERING DESIGN
• Detailed Crossing Profile Design
• Operating Stress Calculations
• Installation Stress Calculations
• Free Stress Minimum Bending Radius
• Estimated Fluid Quantity Calculations
• Pipeline Buoyancy Analysis

28. Equipments
• Drilling Rig
 American Augers DD625
 American Augers DD440T
 Astec DD3238
 MPR 6000 MUD SYSTEM
 TULSA IRON 1000 MUD
SYSTEM

29. HDD Landfalls - General Details
• Rig located onshore, (can be placed on
marine spread offshore).
• Drill to exit point from beach entry subject to
pipe size and soil conditions.
• Engineer coating on pipe-string to give
temporary stability during the laying of the
string and to have a low friction value when
being pulled through the hole.
• Pipe-string is preferably pulled directly into the
hole either from a laybarge or from a pre-laid
position on the seabed.

30. Offshore Support “Back Reaming”
• Support vessel
– Locate and survey exit
point
– Pick-up wash pipe
– Stage prereaming
operations

31. Offshore Support Pipeline Pullback
• Support vessel
– Hold product string
– connection for pullback

32. Intercept Drilling
• Concept developed from oilfield technology for
tapping into capped wells.
• Requirements
– Two HDD Maxi Rigs
– Insert Casings at each Drill Site.
– Drill from one side to within a notional 500m of the
opposed rig
– Drill from the opposed side to intercept the first drill

33. HDD Intercept Drilling
• Restrictions
–Ground Conditions (Rock, Stiff clays)
–Depth of Geotechnical Survey
–New
–Repeatability.

34. INSTALLATION METHODOLOGY FOR INTERCEPT CROSSINGS
• Mobilize Equipment and Personnel to Site.
• Survey and re-establish entry and exit co-ordinates.
• Set up Equipment at both sides of the River (Rig, mud unit and
Steering Tool and wire coils).
• Install casing in alignment to entry angles to firm ground bed at both
sides.
• Drill 2nos Pilot holes into the intersect area, from both sides of the
river.
• Switch the Guidance system on the shorter crossing to the Passive
Magnetic ranging system (PMRS) mode and establish contact
between both guidance systems.
• Retrieve the short crossing as the longer crossing is steered into the
same hole as the shorter crossing, using the PMRS as a homing
device to the exit point.
• Disconnect both guidance systems.
• Connect a reamer and commence the hole expansion process

35. My Various Site HDD Experiences
• 24” X 1.5Km River Niger Crossing At Kwale For Daewoo/NAOC In
March Of 2004 Using 300Ton (625,000#) American Augers Rig
• 40” X 760M Road & Creek Crossing For Daewoo/SPDC In January
201O Using The 300Ton American Augers Rig.
• 18” X 1.3KM Uruan River Crossing at Uruan, Akwa-Ibom State.
(swamp)
• 18” x 950m Aka-Ibonda River crossing at Creek Town, Cross River
state. (swamp)
• 18” x 704m Calabar River Crossing at Calabar. (land)
• 18” x 650m Itu River Crossing, C.River State. (swamp)
• 18” x 550m Esu and Esukudo River crosings, CRS. (swamp)
• 18” x 363m Abak river Crossing, Aks. (land)

36. My Various Site HDD Experiences
 30” x 300m Road Xing – Zakhem Constr Ltd (October 2011)
 12” x 300m Liverpool River Xing – Oando Plc (September 2011)
 Test Pilot Hole Bore, 300m – Oando Plc (August 2011)
Installation Period: November 2011
 24” X 1.7km Oron River Crossing
 24” x 1.2km Uruan River Crossing
 24” x 950m Calabar River Crossing
 24” x 650m Itu River Crossing
 24” x 600m Esu River crossing
Client – NIPP/KAZTEC
Status– Swamp Site Preparations and Mobilization
Installation Period – 2nd Quarter 2012
16”,6” and 4” X 700m Mid-Stream, Bundle Crossing across
Commodore Channel Lagos.
 Method – HDD, Shore Approach.
Client – Oando Plc
Status – Engineering and Design Completed

37. HDD EQUIPMENT & CREW WORKED WITH
 RIG – AMERICAN AUGERS DD625 HDD RIG (2004)
 CAPABILITY – 300 TON (625,000 LB) PULL BACK
CAPABILITY (CAPABLE OF PULLING 3.5KM X 12” P/L)
 PUMP/CLEANING SYSTEM – TULSA RIG IRON 10,000
GALLONS MUD CLEANING / RECYCLING SYSTEM
 750GPM WEATHERFORD T425 MUD PUMP
 6” SYKES TRASH PUMPS (3 NOS).
 3KM 6-5/8” FH DRILL PIPES.
 VARIOUS SIZES OF FLY CUTTERS/HOLE OPENERS AND
BARREL REAMERS Frm 12” to 60”.

38. HDD EQUIPMENT & CREW WORKED WITH
 RIG – AMERICAN AUGERS DD440T HDD RIG (2009)
 CAPABILITY – 200 TON (440,000 LB) PULL BACK
CAPABILITY (CAPABLE OF PULLING 2.5KM X 12” P/L)
 PUMP/CLEANING SYSTEM – MPR 6000 MUD CLEANING /
RECYCLING SYSTEM/PUMPING SYSTEM.
 200 GALLONS MUD RECYCLING UNIT COMPLETE WITH
SHAKERS, DESANDERS AND DESILTERS.
 3 NOS 6” SYKES TRASH PUMPS.
 2.5KM 5” X 4-1/2 IF DRILL PIPES.
 VARIOUS SIZES OF FLY CUTTERS/HOLE OPENERS AND
BARREL REAMERS

39. HDD EQUIPMENT & CREW WORKED WITH
 RIG – ASTEC 3238 DIRECTIONAL DRILLING RIG
 CAPABILITY – 15 TON (30,000 LB) PULL BACK
 PUMP/CLEANING SYSTEM – MX 330 MUD CLEANING /
RECYCLING SYSTEM/PUMPING SYSTEM.
 2 NOS 4” SYKES SUBMERSIBLE PUMPS.
 750M 2-3/8” DRILL PIPES.
 VARIOUS SIZES OF FLY CUTTERS/HOLE OPENERS AND
BARREL REAMERS

40. The Benefits of Directional Drilling
• Minimum environmental disturbance
• No interruption to shipping, road or rail traffic
• Accurate installation
• Shorter construction schedules
• Lower installation costs
• Minimal maintenance
• Greater protection from external damage

41. • Requires no concrete coating.
• Cheaper alternative to open cut.
• Less logistics
• Can be buried up to 30mtrs, hence out of
the reach of vandals.
• Fewer personnel.
• Depth of cover add as additional
protection to the pipe.
• Accurate As-Built Documentation.
The Benefits of Directional Drilling cont.

42. THANK YOU
FOR
LISTENING