In oilfields where increase in reservoir contact is crucial, openhole multilateral wells have become one of the prevalent completion techniques. Stimulation in these wells is usually lengthy, as coiled tubing (CT) hydraulic actuated toolstrings cannot access more than one non-natural lateral in the same run. The advent of an innovative electrically actuated CT multilateral assembly has overcome challenges associated with hydraulic actuated multilateral tools, enabling the industry's first extended-reach stimulation with CT hydraulic tractor in a six-legged lateral well.

The first integration of an acid-resistant, electrically actuated multilateral entry tool (eMLT) with direction and inclination (D&I) measurements, and electrical circulation valve (ECV), with CT hydraulic tractor, allowed the first-time featuring of a CT extended-reach intervention with a multilateral assembly that did not require hydraulic isolation of the CT tractor, enabling selective, on-command actuation of the CT tractor, and accessing multiple non-natural laterals in the same run. The novel CT assembly leveraged real-time downhole telemetry, including gamma ray, casing collar locator, for accurate depth correlation, and axial force, and CT internal and annulus pressure for precise control of the hydraulic tractor.

After a series of function tests to validate the compatibility between the components of the electrically actuated multilateral entry assembly and the CT hydraulic tractor, a newly drilled well with six lateral legs was selected for the first global application of the novel solution. The intervention successfully navigated a 90-ft CT multilateral bottomhole assembly across six 6 1/8-in. openhole laterals and motherbore, and stimulated near 21,200 ft of reservoir section. Following CT lockup inside the deepest non-natural lateral, the CT hydraulic tractor was selectively activated, providing around 3,000 lbs. pulling force, and enabling reaching the total depth (TD) of the lateral. Then, from the lateral TD, the ECV was actuated, allowing selective isolation of the CT hydraulic tractor, redirecting the CT flow to the ECV annulus and pumping the stimulation treatment in uphole direction. Throughout the operation, the lateral mapping and entry process was conducted at the first attempt, with D&I module providing confirmation of lateral entry. When compared to conventional CT multilateral interventions, the implemented solution saved nearly 175 hours of offshore rig time, reduced the need for extensive CT cycling, and preserved more than 3,000 bbl of water.

The first global application of the electrically actuated CT multilateral assembly with hydraulic tractor set new heights in terms of efficiency and sustainability for CT multilateral interventions. Also, it offers opportunities to combine downhole applications that were previously difficult or nearly impossible, making interventions in complex downhole environments more effective and efficient, unlocking and optimizing well performance by enabling enhanced reservoir access and productivity.