(17) Minimizing Failure Frequencies in the Midcon Area by Root Cause Failure Analysis (RCFA) Methods And Design Optimizations

Deviated wells have now been the standard form of drilling, increasing well life and production but also creating challenges in the Artificial Lift System, specifically the Reciprocating Rod Lift (RRL). With aggressive drilling deviations rod string guiding becomes a requirement, landing pumps in 45+° zones a normal, and gas mitigation a complete necessity to achieve target productions. 

In 2018, An operator in the MidCon introduced RRL systems to their wells; these (7,000ft) deviated wells utilize conventional pumping units (640 / 912 / 1280’s) and mid-strength sucker rods as the rod of choice. Since then several failures have been observed in the pump, tubing and most frequently in the sucker rod string which have been fatigue related with corrosion and compression as attributing factors to the break.

Over the past 3 years, the Weatherford team has worked together to optimize the well designs based on past failure history observed. This paper will discuss the challenges observed, actions taken, and positive results which have minimized the failure frequencies significantly.