A Simulation-Based Assessment of Pipe Sticking Mechanisms in Extended-Reach Wells: Case Study of Niger Delta Fields

Stuck pipe remains a major contributor to non-productive time in drilling operations, especially within complex geological environments such as the Niger Delta. This study presents a comprehensive modelling and simulation analysis of pipe sticking tendencies using WELLPLAN, focusing on a highly deviated extended-reach well with a 17.5-inch surface hole section, 13⅜-inch casing set at intermediate depth, and an openhole interval drilled with water-based mud. The simulations incorporate actual field data including well trajectory, casing program, drillstring configuration, formation pressure regime, and operational practices typical of Niger Delta development wells. The objective was to quantify the mechanical and hydraulic responses of the drillstring under varying operating conditions, specifically hook load, mud weight, and openhole friction factor and to evaluate their individual and combined impacts on stuck pipe initiation. Results show that increasing hook load reduces the measured depth of the stuck point but concurrently decreases the apparent stuck weight due to elastic stretch of the drillstring, emphasizing the need to manage over-pull within safe mechanical limits. Variations in mud weight significantly affected both stuck point depth and stuck load, demonstrating the sensitivity of differential sticking to the balance between hydrostatic pressure and formation pore pressure. The openhole friction factor had a strong influence on sticking behaviour in lower-tension conditions, although its effect diminished at higher hook loads where axial stress dominates. The modelling also highlighted the importance of casing placement and hole geometry, revealing that inadequate standoff in the openhole section amplifies mechanical sticking potential, particularly during tripping and reaming operations. The study highlights the complex interplay between wellbore geometry, drilling-fluid properties, and operational parameters in stuck pipe development. The findings underscore the value of predictive simulation for optimizing drilling parameters, improving hole cleaning, guiding mud weight selection, and minimizing openhole exposure. This integrated approach provides a practical framework for reducing non-productive time and enhancing well integrity in deviated and extended-reach wells across the Niger Delta.