Conventional model
limitations
EQUATIONS
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Data demonstrating the impact of in-situ stresses in
UBD of horizontal wells are
often overlooked using conventional models.
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Researchers have looked
at the effects of in-situ
stresses on the wellbore
and, based on the data,
conducted studies to reveal
the mechanism of wellbore
collapse during overbalanced drilling (OBD). 1 2
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Studies of UBD operations have established a
coupled reservoir-geome-chanics model that simulates the interaction between reservoir flow and
deformation. 3 The model
can determine wellbore-stability design and sand-production risk evaluation
in the formation during
production or UBD. 4 The
model offers a practical
technique to evaluate UBD
of a horizontal well in a depleted reservoir.
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