1. Introduction to Directional Drilling
Khalifah Al-Amri
Senior Drilling & Workover Engineer

2. Outline Definition What Are Directional Wells ? Directional Well Types
Why Drill Directionally?
Planning A Directional Well Path
How To Drill Directionally?
Horizontal Drilling
Complex Wells

3. Definition
Directional drilling is the science of deviating a well bore along a planned course to a subsurface target whose location is a given lateral distance and direction from the vertical.

4. What Are Directional Wells ?
Directional wells are deviated from vertical (straight)
Directional wells are drilled with intentional control to hit a pre-determined target:
inclination (angle)
azimuth (direction).
Think 3-D when directional

5. Directional Well Types
Vertical Type
Slant (J) Type
“S” Type
Horizontal Type
-the Kick-off point
is defined as a point in the wellbore at a given vertical depth below the surface location where the well is to be deviated away from vertical in a given direction up to a given inclination at a given built rate
is made by considering the geometrical well-path and geological characteristics
the optimum of the well is a function of the maximum permissible build/drop rate and the location of target

6. Why Drill Directionally?
Inaccessible Locations
Sidetracking
Salt Dome Drilling
Fault Controlling

7. Why Drill Directionally?

8. Planning A Directional Well Path
TVD
EOW MD
KOP HD
Inc N
Dir
Kick Off Point
Build Up Rate
Azimuthal Direction
Inclination Angle
True Vertical Depth
Measured Depth
Horizontal Displacement

9. How To Drill Directionally?
Slide & Rotate Mode
Downhole Motor
Bent Sub
Fixed
Adjustable
Surveying Tool
Media of Transmission

10. Horizontal Drilling Types of Horizontal Wells:
Long Radius (2°-8°/100’)
Medium Radius (8°-30°/100’)
Short Radius (30°-60°/100’)
Ultra Short Radius (60°-200°/100’)

11. Horizontal Drilling Applications: Horizontal Wells Vertical Wells
Gas and Water Coning:
Longer horizontal drain hole increases the exposure of the pay-zone
Allows a higher production rate at lower drawdown pressure resulting in less coning
Horizontal Wells
Gas
Vertical Wells
Oil
Water
Gas Coning
Water Coning

12. Horizontal Drilling Other Major Applications:
Maximum reservoir exposure
Naturally fractured tight reservoirs
Thin dry reservoirs
Less wells needed to develop a field

13. Complex Wells
Stacked Laterals

14. Complex Wells
Fishbone Wells

15. Complex Wells
Stacked Fishbone Wells

16. Complex Wells
Multiple-Branch Multilateral Wells