Biplav Chapagain and Vladimir Pechenkin
DV8 Energy
The oil and gas industry has used Variable Frequency Drives (VFDs) for decades to match production to inflow. In sucker rod pump applications, it is well understood that optimizing pumping speed dramatically improves pump efficiency and failure rate. However, the same technology provides the opportunity to make multiple speed changes in a pumping cycle.
The effects of speed changes within a pumping cycle were analysed using predictive modeling, advanced rod stress and sideload calculations. A 5-year long trial was conducted on a population of 28 wells. A speed profile was selected to reduce rod failures, while maintaining production and pump efficiency. 19 of wells saw a fall in failure rate, improving the average time between failures by over 35%.