Abstract:
Introducing bore instability phenomena, drilling fluids to/and other
wise stable formation causes a stresses concentration that extended away form
the hole which could exceed the formation strength. The severity of these
affects on hole failure depend on the pore pressure and the cohesive strength
of the formation.
This research work is studying Greater Bamboo area block 2A of Unity
in Southern part of Sudan. The area is divided into four producing fields and
the first discovery in 1982 by Chevron. The Bamboo West is a very complex
feature bounded by faults both to the east and the west. Preliminary review
showed all the drilled wells have been drilled up to Bentiu-3 and the major
hydrocarbon volume is also restricted up to that level.
The study starts by collecting data, evaluating and analyzing, logical
arrangement of daily field informatios in contingency with other running
operations. Run a correlation analyzing, designing, targeting and vise versa to
get the optimum.
The failure envelope stresses, mud pressure and mud weight calculation
were done to prevent hole collapse in Bamboo west field. Using the drilling,
hydraulic and
logs parameters getting Z1, Z3, Z00, and Zrr. Then the save mud pressure
and weight to be use in the Bamboo West was observed.
Finally; the proposed parameters, stress distribution, suggested mud
weight should be treated as a base for farther studies and deeper investigations
when there is complete required information.
