Successful Application of Innovative Well Intervention Technologies to Effectively Stimulate Extended Reach Wells

Abstract Well interventions with coiled tubing (CT) have played a vital part in increasing well productivity. CT intervention challenges in 2.25" highly restricted extended reach wells demand technological solutions, excellent planning and in-place tailored procedures. Fluid placement and effectively maximizing reservoir contact are critically important elements during CT interventions for open-hole matrix acid stimulations. Fluid delivery was accomplished with multiple extended-reach techniques, including concentration of friction reducer and volumes, contributing to extending the reach. Technologies such as CT tractors and agitators to increase the reach were selected after considering their performance in the wells. A specially tapered CT string was also employed in the field. Effective fluid placement was achieved through distributed temperature sensing (DTS) providing a real-time optimized pumping schedule. The CT simulator predicted the CT lockup depth to within 5% of actual depth reached for the CT interventions. This allowed for proper selection of downhole tools and planning of fluid volumes to operate the hydraulic downhole tools. One of the most effective practices was cleaning the wellbore casing shoe with a high-pressure jetting tool (HPJT) to clean any organic or drilling materials, leading to a reduced friction coefficient. This HPJT run increased the reach by an average of 23%, and also reduced the operation time during the stimulation by 15%. Real-time tension-compression information from the bottom-hole assembly assisted in estimating the lockup depth and provided confirmation of the extended reach tool activation. The ERW's open-hole coverage was maximized, delivering an increased well productivity on every intervention. These engineered solutions illustrate the potential for CT interventions in extended-reach horizontal wells to move the dial and contribute to well productivity. Continual innovation and introduction of new technologies not only play a key role in meeting objectives, they are essential for constantly pushing the boundaries in these ultra-challenging well conditions.