Sucker Rod Pump

The relative motion between sucker rods and tubing in rod-lifted wells, particularly in corrosive fluids, leads to degradation mechanisms that often cause material loss, commonly referred to as wear. In U.S. unconventional wells, this wear mechanism accounts for over 50% of the operational expenditure (OPEX) in rod-lifted systems.

Through the application of Root Cause Analysis, the primary mechanisms responsible for this wear—tribocorrosion and three-part abrasion—were identified. These mechanisms can occur individually or in combination.

Rod-lifted wells in U.S. unconventional fields have been pushed beyond their limits since the onset of the unconventional reservoir (UR) revolution. Sixteen years later, the demand for higher production rates with rod-lift systems remains strong. As the industry progresses toward the Aspirational Goal of 1,000 barrels per day (bfpd) at depths of 10,000 feet (1K @ 10K), new challenges continue to emerge.

Through the motion of a rod pump well, stress oscillations typically appear in the rod string at the beginning of both the upstroke and downstroke phases. This dynamic phenomenon has several adverse consequences on the well. The load in the road string is drastically increased, thus reducing its service life; the plunger velocity is higher thus increasing erosion and wear on the pumps and the stress on the gearbox and the pumping unit also increases general wear and tear.

The upstream oil and gas industry faces significant challenges in optimizing production from aging assets, particularly in managing the vast amounts of unstructured data generated by rod lift systems. This paper presents field results from the deployment of Cognitive Card Recognition (CCR), a machine learning-based solution for automated dynacard analysis and anomaly detection in rod lift operations.

Operators have been challenged in identifying physical defects or discontinuities when adopting continuous rods, in reciprocating rod pumps and PCP wells. Historically, the only method used is a visual, imprecise inspection, often resulting in running bad rod back in hole or removing good rod prematurely driving up LOE. This has been viewed as a barrier to entry for widespread adoption of continuous rod in the Permian & Delaware basins.

Operators have been challenged in designing rod pumping solutions for the life of the well in deviated, horizontal and S curve wells. Overcoming frictional side loading in high-rate producers converting earlier from ESP to rod pumping. The first 6 months of the conversion is the most critical time where operators want to reduce the cost of ESP workovers going to rod pumping earlier. The challenge is rod and tubing wear or corrosion enhanced rod ware, produced solids and gases.

This paper builds on last year's paper, which detailed the development of a new gas separation method for rod pump wells operating under gassy conditions, without limiting the liquid production rate. In this second part, the focus shifts to results from new applications in a different field within the Midland Basin, highlighting lessons learned from various BHA configurations, performance outcomes, and new challenges encountered during the evaluation process.

Pump valve cages play a critical role in fluid flow, and indirectly affect the integrity of the sealing components. Cage beat-out is a common problem, caused by deformation of the steel due to repeated impact from opening or rattling while open. In addition to the cage deformation, damage to the ball itself can also result in poor seal when the valve is closed. The Impact Resistant (IR) cage was developed to absorb the impact of the ball without permanent deformation. The use of a resilient plastic cage has proven successful in 5,000 installations over the last 8 years.

This paper explores the Horizontal Valve System (HVS) and its ability to enhance vortex fluid flow profiles in downhole environments. Initial field trials demonstrated the HVS's effectiveness in lowering pump placement resulting in larger production outcomes, prompting further laboratory testing. The study replicates downhole conditions to compare lab results with field data, highlighting how the HVS extends vortex flow profiles, increases fluid flow efficiency and increases pump longevity.

The challenges frequently associated with Endless Rod applications primarily arise from corrosion, particularly mechanical corrosion where the inhibitor film is removed, leading to inadequate protection and allowing corrosion to develop. Barrier coatings can protect the rod from corrosion, preventing the formation of stress risers on the rod surface that, under cyclic loading, can easily propagate across the rod body until there is insufficient section to sustain the load, causing it to fail.