WellPilot® Optimization Controller for Rod Pumping

Since the advent of automation in the oilfield, rod pump control has become an industry standard. However, while the rod pump controller (RPC) has advanced in reliability and accuracy, the basic principles remain unchanged. Those principles include load and position control minimizing pump-off and providing data for analysis of the well. Many advances have been made to improve the communication of data, accuracy of the data collected, and the logic used to provide control, but there has never been a revolutionary jump in technology that fundamentally advances the way rod pump control is done until now.

The WellPilot rod pump optimizer (RPO) jumps the evolutionary trend of technology with major advances in electronics that include built-in capabilities for future advancements. To control the pumping system with unprecedented accuracy, the WellPilot controller uses an unabbreviated Everitt-Jennings¹ algorithm with finite differences to solve the wave equation. Weatherford has enhanced the algorithm and patented the application for use in the WellPilot controller and LOWIS™ software.

Why is this important? Abbreviated equations provide accurate well analysis in most situations, but not all. The comprehensive finite difference analysis provides highly accurate control by percent of pump fillage for all types of well configurations in all conditions.

Additionally, the WellPilot controller has a large number of input/output (I/O) ports that provide the framework for incorporating future devices.

The Everitt-Jennings card from the WellPilot controller lines up directly on the zero axis line demonstrating “effective load”.

Abbreviated methodology from the “Gibbs” card must be adjusted manually for an accurate picture.

¹Everitt, T.A. and Jennings, J.W., SPE 18189, An Improved Finite-Difference Calculation of Downhole Dynamometer Cards for Sucker Rod Pumps.