Sucker Rod Anti-Buckling System to Enable Cost-Effective Oil Production

Abstract

In days where the oil price is low, cost optimization is of vital importance. Especially in mature oil fields, the reduction of lifting costs by increasing the mean time between failure and the overall efficiency helps to stay economical and increase the final recovery factor. Today a significant portion of artificially lifted wells use sucker rod pumping systems. Although its efficiency is in the upper range, compared to other artificial lift systems, there is room for improvement and system optimization. This paper presents the benefits of the field-tested Sucker Rod Anti-Buckling System (SRABS), which can entirely prevent compressive loads from the sucker rod string by a redesign of the standing valve, the advantageous use of the dynamic liquid level, and the on a case-by-case basis application of a tension mass. This results in complete buckling prevention and a reduction of the overall stress in the sucker rod string. The resulting reduction in the number of well interventions in combination with the higher overall pumping efficiency prolongs economic production in mature oil fields, even in times of low oil prices. The analysis of SRABS, using simulations, showed a significant increase in the overall efficiency. The SRABS performance and wear tests under large-scale conditions are performed at the Montanuniversitaet Leoben's Pump Testing Facility and in the field. The self-developed Pump Testing Facility can simulate the conditions of a 500 m deep well, including the effects of dynamic liquid pressure and temperature. Testing of SRABS has identified major benefits in comparison to standard sucker rod pumps. The results of intensive testing are used to optimize the geometry of the pump body itself and to improve the wear resistance by selecting optimal materials for the individual pump components. SRABS itself can be applied within every sucker rod pumping system; the installation is as convenient as for a standard pump, and manufacturing costs are comparable with those of a standard pump. This paper shows the high performance of the SRABS pumping system in comparison to a standard sucker rod pump.