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

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

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.

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

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

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

Why Drill Directionally?

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

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

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’)

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

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

Complex Wells Stacked Laterals

Complex Wells Fishbone Wells

Complex Wells Stacked Fishbone Wells

Complex Wells Multiple-Branch Multilateral Wells