(18) CORROSION- FATIGUE RESISTANT SUCKER RODS

Corrosion fatigue (CF) is an important concern for structures that are exposed to cyclic loads in corrosive environments, especially in the case of oil and gas operations like drilling, offshore risers or sucker rods in artificial lift. Considering the current combination of complex wells completions and the increase of water cuts, the CO2, H2S and Bacteria represent a higher risk for CF failures in sucker rods. This combined effect force operators to choose a steel for either corrosive environments or high loads and increase the chemical inhibition programs.

In response to the new downhole challenges, a research and development program (R&D) has been created to analyze the key factors that affect sucker rods performance under CF. As a result of this R&D program, a new corrosion-fatigue resistance sucker rod has been developed. The present paper summarizes the development process, the new sucker rod characteristics and its performance.