Advanced Hybrid Fiber Optic-Enabled Coiled Tubing Techniques for Precision Management of Multistage Wellbore Operations: An In-Depth Case Study for North Kuwait Deep Gas Well
Authors: Abdelbagi Mamoun , Abdel-Basset M. , Slama Hedi , Badrawy Kareem , ALHussaini Hadeer , Al-Otaibi Y. , Hassan Y. , Sunagatov Rustem 
Published: February 2025

In the complex geological setting of North Kuwait's Jurassic Gas fields, open-hole multistage completions are essential for optimizing the initial segmented stimulation operations. These techniques allow for later selective control—opening or closing of the FracPort sleeves—to facilitate either restimulation or water shut-off (WSO) at individual stages. This study showcases the pivotal role of real-time coiled tubing (CT) telemetry in mitigating the uncertainties traditionally associated with conventional coiled tubing FracPort sleeves adjustments in such intricate wellbore environments.

The multistage completion with multicycle FracPort sleeves were strategically chosen to perform an efficient acid fracturing treatment in 6 stages. The FracPort sleeve is run in a pinned configuration with a ball seat and is sheared when desired by dropping the corresponding ball size, providing positive pressure indication that the specified port has opened before fracturing. Later, the sleeves can be opened, closed, and reopened, enabling production management using CT hydraulic activated shifting tool for selective stimulation and production from distinct or combined producing zones. Studies have shown that restimulation/refracturing can be an effective practice in tight reservoirs. Additionally, these sleeves facilitate WSO in future.

When wellbore conditions do not allow a clear surface indication, monitoring critical downhole CT load parameters during shifting operations is crucial to achieving successful intervention in deviated and horizontal wells. Downhole sensors were used during the manipulation of the FracPort sleeves, providing indication of latching, profile shifting, and then releasing of the shifting tool, including depth control while locating the shifting profile at every FracPort stage. To ensure real-time confirmation of sleeve opening and closing, the operation utilized fiber optic-enabled coiled tubing with Real-time downhole telemetry (Pressure, Temperature, Casing Collar Locator "CCL", Gamma Ray, Load, Torque) and Distributed Temperature Sensing (DTS) providing timely insights into actions during the shifting operations, validating sleeve closure by comparing temperature change at the port depth pre- and post-shifting, in addition to the pumped fluid direction and zonal isolation between the stages.

The integration of fiber optic-enabled real-time downhole telemetry has revolutionized the confirmation and monitoring of sleeve manipulations. By providing live feedback on critical parameters —temperature changes, latching, and sleeve shifting—this workflow ensures enhanced operational control across both deviated and horizontal wells. The combined capabilities for milling, shifting FracPort sleeves, stimulating, conducting surveillance, and implementing nitrogen lift systems during a single coiled tubing setup exemplify significant advancements in well intervention. ultimately leading to improved operational efficiencies and resource recovery.

This innovative approach sets the stage for future advancements in wellbore management, contributing to improved hydrocarbon production and reservoir performance plus relieving of asset busy Work Over rig schedule.