Casing DrillingIn the casing drilling process, the well is
drilled and
cased simultaneously, using standard oilfield casing.
Thebottomhole assembly (BHA) is latched into the bottom joint of
casing and is run and retrieved through the casing, via wireline.
Using wireline to convey the BHA is much faster than conventional
tripping with a drill string.
For directional or horizontal wells, the BHA can be fitted with
conventional directional equipment, such as mud motors and
measurement-while-drilling (MWD) tools. Since these tools are run
and retrieved inside casing, they are protected from the harsh
downhole environment while in transit.
South Texas Casing Drilling
Rig
Casing Drilling Utilizes the Casing Itself as the
Drillstring.
When casing depth has been reached the drilling assembly is
removed by wireline, and the casing is cemented in place.
Benefits
For operators it: Reduces drilling time and lowers costs
Improves wellsite safety and well control Reduces unscheduled
events Provides a quicker return on investment Lessens
environmental impact
Benefits
For Drilling Contractors: Eliminates the need for drillpipe and
drill collars Eliminates the need for double and triple masts
and
heavy setback areas Makes rig moves easier Reduces labor
requirements Reduces fuel consumption and wear on equipment Lessens
the chance of pipe-handling incidents Lowers capital
requirements.
Benefits
For service companies: Opens up a new service market Provides an
additional application for existing
tools and an opportunity to develop new tools to gain market
share
Extends tool life by protectiong tools during running and
retrieval
Reduces time and risk in recovering from downhole tool
failure.
