Increase Run Time and MTBF by Pumping the Curve with Thermoplastic


Victoria Pons, Anne-Marie Weaver and LJ Guillotte, Lightning Production Services
Justin Lundquist, Revolution Resources  

Shale wells have become deeper and are intentionally drilled deviated or horizontal with more extreme side loading conditions, which increases operating costs. Pad drilling, where many trajectories issue from the same pad into different producing zones at deeper depths cause highly deviated wellbores. Another common practice is to drill vertically then break off at 90 degrees angle and continue horizontally for several miles. This phenomenon can make lifting fluids using rod pumps problematic due to the extreme deviation and forces the operator to compromise production for the safety of pumping the well from the vertical section above the curve. Due to the rock properties of these formations, long laterals with high proppant result in large production volumes with exponential decline, making the ability to lift high volumes of fluid in the early stages of the well a priority. In an effort to increase production and reduce gas and slug flow, operators have attempted to pump the curve with varying levels of success. Thermoplastic liners, which are mechanically bonded to new or existing tubing, significantly increase run time by preventing rod/pump on tubing contact. Thermoplastic liners also remove the need for rod guides and protect the tubing from corrosive reservoir fluids, therefore improving corrosion related failures. Finally, thermoplastic reduce friction forces by half compared to bare steel and by two thirds compared to rod guides, thus decreasing operational expenses. The effects of different corrective measure to deviation and their respective coefficients of friction is detailed and discussed in this paper. In this paper, results from a case study where thermoplastic liner was installed on five high failure rate wells showing that pumping the curve is an economic and feasible option for operator, are presented.