Torque-Balanced Sour-Service Cable and Intelligent Extreme Wireline Tractor Enables Access to Deepest Sour Reservoirs in UAE

Abstract

Abstract Advanced torque-balanced sour-service wireline cable in combination with an intelligent sour-service slim tractor overcomes wireline conveyance challenges to obtain high-quality production logging and well integrity data from extended-reach drilling (ERD) wells in a hostile environment. Using the data obtained by this method, the operator evaluated the well production profile, confirmed the reservoir properties, and assessed the integrity of wells. The use of this technique also enabled the operator to successfully restore the production in a well with malfunctioning inflow control devices (ICDs). Wireline conveyance in ultra-sour, deep ERD wells is extremely challenging due to the limitations of existing conveyance technologies. This paper presents an innovative method of combining a torque-balanced sour-service wireline cable and an intelligent sour-service slim tractor to successfully convey production logging tools in over 35 ERD wells with more than 100 cable descents including conveyance to the deepest depth ever in a sour well in the UAE. The following methods were used: 1) Model well tortuosity to estimate tractor forces and navigation challenges. 2) Select a high-strength, torque-balanced, sour-service cable, and a small-diameter, intelligent, sour-service tractor. 3) Design a fit-for-purpose tool configuration and operation strategy to navigate complex completions. 4) Establish a core team of key personnel from field operations and the operator with direct feedback to the product manufacturing center to enhance equipment design and performance. Deep reservoir access up to 26,870 ft was achieved. Successful navigation through step changes between the upper and lower completion and across multiple ICDs demonstrated the tractor's ability to traverse varying internal diameters throughout the intervention. The interventions represent over 480,000 ft of cumulative tractoring. Simultaneous acquisition of production log data while tractoring down ensured superior quality of data and improved efficiency of the operation. Repeatable and reliable performance of equipment enabled rapid turnaround between operations. Accurate determination of horizontal lateral zonal contributions, fluid source, completion integrity, and reservoir saturation were made possible for the first time in this field. Successful deployment of this combined conveyance solution has created a paradigm shift for safe and efficient intervention of extended reach development wells with high H2S/CO2 concentrations.