Directional Drilling - Rui Francisco 36344 Petroleum Engineering Seminars
←
→
Page content transcription
If your browser does not render page correctly, please read the page content below
Directional Drilling
Rui Francisco 36344
Petroleum Engineering Seminars
Index
Introduction
History
Aplications
Profile
Equipment
Conclusion
Petroleum Engineering Seminars
Introduction
Directional drilling is the art and science involving the intentional deflection of a
wellbore in a specific direction in order to reach a predetermined objective below
the surface of the earth.
(The practice for drilling non-vertical wells)
Well Path Deviat. Survey Data Record Geological Data
Rate of Build / Drop _ DLS – Dog leg severity is a measure of the amount of
change in the inclination, and/or azimuth of a borehole, usually expressed in
degrees per 100 feet (30 meters) of course length.
DLS > 4º a 6º / 30 meters Drag and Torque; Keyseat
Petroleum Engineering Seminars
History
Industry Driven vs Technology Driven (How – Where – Why)
Many prerequisites enabled this suite of technologies to become productive.
Probably, the first requirement was the realization that oil wells are not
necessarily vertical – 1920s.
The first controlled directionally drilled well was drilled in
the Huntington Beach Field in 1930 to tap offshore
reserves from land locations.
Directional drilling became more widely accepted after a
relief well was drilled near Conroe, Texas in 1934.
In the erlys 1940s the wells were drilled with horizontal
displacements from 30 m to 150 m.
The first multilateral well was drilled in the Soviet Union
in 1953
Petroleum Engineering Seminars
History
During the 1980s, directional drilling was difficult and comparatively costly. As a
result, it failed to achieve broad acceptance wthin the industry.
The 1990s upsurge in exploration activity saw a sustainable interest in
directional drilling, and the technique emerged as the prefered option for
production wells in several countries.
Measurement While Drilling – 1978
Steerable Motors – 1986
Acceptable Surveys – 1992
Rotary Steerable Systems – 1997
Today, directional wells have been drilled in every oil and gas basin, and the
technology is so efficient that has become a standard industry tool.
Oil and Gas companies spend around USD 20 billion on drilling each year, from
which 15% are attributed to losses
Petroleum Engineering Seminars
Applications
Multiple sidetrack for
Side track well, to go well logging or Multiple wells from a
around a stuck BHA reservoir better single structure
positioning
Petroleum Engineering Seminars
Applications
Steeply dipping sands
Inaccessible surface Drilling around salt
can be drilled with a
location domes
single wellbore
Petroleum Engineering Seminars
Applications
HDD. Increasing
Fault drilling at higher exposure of the
Relief well drilling
incident angle reservoir to increase
productivity
Petroleum Engineering Seminars
Applications
Optmize Reservoir Exploitation
Vertical Wells Directional Wells
57 2
2.000 m3/d – 19 years 5.000 m3/d – 7,6 years
Disavantages
Drag and Torque
Rate of perfuration
Costs
Adjustment and repair works
Sand influx
Petroleum Engineering SeminarsProfile
Trigonometry
Software
Petroleum Engineering SeminarsEquipment
Technology
Drilling / Steering Measurement Data
Tools Instruments Transmission
Rate of Penetration
Objective
Accurate
Direction Measurement
Deviation
Efficiency While Drilling
Surveys
Safety
Equipments
Rotary Steerable Electronic Telemetry
Systems Compass Systems
Petroleum Engineering SeminarsEquipment
Whipstock: A long wedge dropped or placed in a petroleum well in
order to deflect the drill
Petroleum Engineering SeminarsEquipment
Rotary Bottom Hole Assembly: Consists of a bit, drill collars,
stabilizers, reamers that affects the trajectory of the bit and,
consequently, of the wellbore.
Petroleum Engineering SeminarsEquipment
Steerable Positive Displacement Motor: Converts the hydraulic power
of the fluid into mechanical power to cause the bit to rotate. Uses bent
subs or bent housing.
Limitations in slide mode:
Difficulty to slide and to maintain orientation;
Poor hole cleaning; Lower penetration rate;
Higher wellbore tortuosity; Differential pressure
sticking
Petroleum Engineering SeminarsEquipment
Rotary Steerable System: A tool designed to drill directionally with
continuos rotation from the surface, eliminating the need to slide a
steerable motor.
Petroleum Engineering SeminarsEquipment
INCLINATION AND AZIMUTH
Pendulum: This method relied on the period of a pendulum's oscillation
adjusted by variations in gravity due to changes in altitude and latitude
Gravity Accelerometers: Measure the Earth’s gravitational field in the
x, y, and z planes
Gyroscopic Sensors: Is composed of a spinning wheel mounted on a
shaft and powered by an electric. The spinning wheel direction is
maintained by its own inertia; therefore, it can be used as a reference for
measuring azimuth
Magnetic Sensors: Measure components of the Earth’s magnetic field.
Must take into account the variations in the Earth magnetic field and any
external interference
Petroleum Engineering SeminarsEquipment
Telemetry Systems
Conversion and transmission to surface of a logging tool measurement
Mud Pulse Telemetry: A valve is operated creating pressure
fluctuations representing the information. The pressure fluctuations
propagate whithin the driiling fluid and is processed to reconstruct the
information
Electromagnetic Telemetry: To transmit data, the tool generates an
altered voltage, wich is transmited to the surface and decoded by a
computer
Wired Drill Pipe Telemetry: These systems use electrical wires built
into every component of the drillstring, which carry electrical signals
directly to the surface
Petroleum Engineering SeminarsConclusion
Uncertainty: Rather than specifyng a
point in space, surveying engineers
consider wellbore position to be within an
elipsoid of uncertainty (EOU)
No Drilling Surprises: Real time
comunications with the headquarters and
computer processing, creating a real time
cycle, which promotes continues review
and refinement of drilling operations
Petroleum Engineering SeminarsConclusion
Acronyms Glossary:
TVD True Vertical Depth
ROP Rate of Penetration
BHA Bottom Hole Assembly
WOB Weigth on Bit
LWD Logging While Drilling
MWD Measurement While Drilling
RSS Rotary Steerable System
DLS Dog Leg Severity
RKB Rig Kelly Bushing
Thank You
Petroleum Engineering SeminarsYou can also read
