Surpassing the Challenges of CT Interventions in a Trilateral Extended Reach Well in the Arabian Gulf
The oil industry in the UAE is striving to advance both onshore and
offshore operations to address technological challenges that will allow for
increased oil production in a safe and efficient manner. Offshore, artificial
islands are being built for the purpose of accommodating up to 300 wellheads on
a single island, with the wells themselves comprising multiple, extended-reach
horizontal laterals. These ground breaking projects present new and exciting
challenges for coiled tubing (CT) interventions, which require extensive
planning and the use of innovative technologies.
Specific challenges were identified during the design phase of
intervening on a trilateral, extended reach well and applying several
technologies enabled us to overcome these challenges to allow successful
execution of a stimulation treatment on the well. Techniques used included
accessibility modelling and CT string selection to achieve maximum reach.
The methodology used and the testing conducted were designed to ensure
that the multicomponent CT bottomhole assembly (BHA) allowed for selective
engagement of each lateral and subsequent horizontal accessibility of each
extended-reach lateral. Operations were performed in the context of the
completion restrictions, diameter of the openhole and cased-hole laterals, and
the requirement to pump large volume acid treatments. Each of these factors
added a layer of complexity to the final CT BHA selection and setup, which had
to operate within a limited range of activation pressures and rates.
Finally, the lessons learned during the execution phase have been
captured and recommendations formulated for moving forward with CT intervention
in similar types of multilateral and extended reach wells. These lessons
contribute to subsequent studies of maximum reservoir contact wells and form
the basis of future development and intervention plans for the offshore and
islands projects in the UAE.