The second presentation of a series of presentations on Operations Geology. Very basic, just to introduce beginners to operations geology. I hope the end users will find this and the following presentations very helpful.
2. Drilling rigs, whether onshore or offshore, are composed of five major drilling rig
systems:
Power System
Circulation System
Rotary System
Hoisting System
Well Control System
Introduction
3. Power System
The power system provides electrical power to the entire drilling rig
Electrical power is generated from the combustion generators
The combustion generators are fueled by diesel
The other Power system components are:
Diesel fuel tanks where the diesel is stored
Alternators which supply AC power to the mud motors
Transformers which are responsible for reducing the voltage of the current
Control panel which is a device that monitors the distribution of power to the rig
equipment
Generator Alternator Transformer Control Panel
4. Circulation System
The Circulation system circulates the mud during the drilling operation in
order to:
Transport cuttings to surface
Clean the bore hole
Cool the bit and the drill string
Support the wellbore & balance the formation pressure
Provide hydraulic power to the bit & drive the down hole motor
5. Major Components of the Circulation System
The major components of the circulating system are:
Mixing equipment: a hopper, a mud gun and
agitators to mix chemicals, fluids and solids to
prepare the drilling mud
Mud pits: a series of interconnected steel tanks
to store mud & equipped with agitators to
maintain the density of the drilling mud
Mud cleaners: Shale shakers, sand traps,
degasser, desander, desilter, mud cleaner
centrifuge and cutting dryer used to separate
drilling mud from rock cuttings, solids & fluids
Mud pumps designed to circulate drilling fluid
down the drill string and back up the annulus
6. Rotary System
There are two types of Rotary systems:
The Lower Rotary System (the Kelly Drive
Bushing):
The rotary table rotates the Kelly and through it
the drill string and bit
The top Drive Rotary System:
The rotation of the drill string is accomplished by
a drive motor located below or attached to the
swivel
The kelly and kelly bushing are not required
Stands of drill pipe (3 joints) are drilled instead
of single joints
8. Hoisting System
To lift & lower the drill pipe and casing during the drilling process.
The major components of the hoisting system are:
The derrick: Provides height for drill pipe vertical movement
The crown block & the travelling block: Responsible for the vertical movement of the pipe
The drawworks: Supports the lifting activities & the replacement of the drilling line
The substructure: Provides height for the BOP (Blow out Preventer) stack & space for
pipe set back & drilling crew
10. Well Control System
Controls the movement of fluids in & out of the well bore
Prevents undesired fluid release from the well (well kicks)
The major components of the well control system are:
Wellhead: suspends the casing & tubing string, contains & isolates the pressure of the tubular
strings; provides interface with the BOP, X-mas tree & the tie back
BOP: Located on top of the well and can be closed if formation fluid control is lost
Christmas Tree: A series of valves that control the fluid flow and helps shut-in the well if needed