Addressing Deepwater Challenges - Weatherford International

alignment device makes running tubing a more expedient
operation. The new OverDrive top-drive casing running and
drilling system leads the next generation of mechanized
tubular running systems, essentially providing all the
functionality of a power tong, elevator, fill-up and circulating
tool, single-joint compensator and torque turn system in one
fully automated package attached to the rig’s top drive.
The end result is a safer, more efficient operation.
Modeling and reserves calculations. Weatherford
Laboratories’ coring and core-analysis capabilities provide the
finite measurements relative to geology and sedimentology.
Geochemistry and geomechanics analysis further expand
data on formation properties and fluid sensitivities, populating
and sharpening reservoir models to further mitigate risk, more
accurately quantify the size of the field and refine reserves
calculations. “We are the world leader in unconsolidated core
preservation and analysis, a key need in many deepwater
exploration plays,” says Bechtel. “Our rock mechanics
expertise is applied to analyze and predict hole stability for
drilling hazard mitigation technologies. And our geochemical
analysis is critical for clients designing production systems that
maximize flow assurance.”
Q
A
How, specifically, do these
technologies help clients meet
their deepwater challenges
Weatherford’s Web site is full of examples of how
these technologies have saved clients significant
amounts of money.
Among the most impressive achievements is a world
record-breaker in the Gulf of Mexico (GoM). In this project
Weatherford provided formation evaluation data in an
8 1/2‐inch hole section that was directionally drilled with the
company’s Revolution ® rotary-steerable drilling assembly
to a depth of 29,314 feet (8,935 meters). Weatherford’s
LWD system was then used in the 6-inch hole section to
successfully drill to 34,189 feet (10,420 meters), setting a
record for the deepest well ever drilled in the GoM.
The job also set a world record for high-pressure LWD, at
29,976 pounds (199 megapascals). Maximum temperature
was 280°F (138°C). Real-time data transmission rates
exceeded 90 percent, and the well was declared a
discovery, with 600 feet (183 meters) of oil sand in multiple
zones. “Equally important were time and cost savings on
a well with a spread cost of US $500,000 per day and an
estimated additional cost of $1.1 million for round trips of the
drillstring from depths below 25,000 feet [7,620 meters],”
says Timmins.
Reliability is a paramount concern when dealing with
deepwater scenarios. And attaining accurate, real-time data
is key to understanding well performance and reservoir
depletion strategy. Weatherford has more than a decade
of experience with optical sensing and intelligent-well
technologies, including 1,136 miles (1,800 kilometers) of
optical fiber and 400 optical sensors installed in wells around
the world. These achievements reflect more than three
million cumulative in-well operating hours for Weatherford’s
optical systems and serve as testaments to the systems’
reliability in critical applications.
“A major operator in the GoM recently used our
displaceable DrillShoe II tool to ream a string of 11 3/4-inch
casing through a problematic rubble zone,” says Hayes.
Previous attempts to work the drillstring through this zone
had been unsuccessful.
Clients have used several variants of MPD in the deepwater
fields of Indonesia, GoM and Brazil to enable drilling through
trouble zones that had thwarted attempts with conventional
drilling practices.
“The list of clients using our mechanized tubular running
services continues to grow almost daily. We are the global
leader in the provision of these services, with over 200
installations around the world, the majority of which are in
deep water,” says Hayes.
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