The shale oil wells are usually able to start producing high fluid rates with enough energy to free flow naturally. After this stage, a high rate artificial lift systems such as ESP or Gas lift is required. But because of the rapid depletion of the stimulated zone during the first year (between 60 – 80% in Eagle Ford), the most flexible form of artificial lift available is used, the beam pumping.

Because the pump depth could reach between 4,000 up to 12,000 ft, the beam pumping system is limited in flow rate. A big surface pumping unit and high strength rod are necessary. Other complex challenges to overcome are the combination of crooked or highly deviated well bore, high GOR, propant or sand flow back and the presence of H2S. Small tubing completions in shale wells, with 2 3/8″ tubing installations, pushes the system to provide high fluid velocity with effective solids transportation in low rates and more inexpensive equipment but with sucker rod diameter restriction to 7/8″ slimhole couplings.

Optimizing artificial lift equipment selection, sizing, and design will ensure longevity of the equipment and continued production. A premium sucker rod connection has a design that allows the use of 7/8″ and ¾″ strings tapers with KD material to work in corrosive environments with regular size pumping units and lighter strings with guides when necessary in wells where 1″ and high strength rods should be the conventional alternative.

This paper explains the experiences of more than 150 strings installed and the benefits achieved in the Eagle Ford.

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