A Simple Method for Predicting the Performance of a Sucker-Rod Pumping System

Abstract

ABSTRACT This paper presents a simple and efficient approach for predicting the dynamic behavior of the sucker rod string. The dynamic behavior of the sucker rod string is an important factor for predicting the performance of a pumping system, and it is presently modeled by a second-order partial differential equation. The proposed approach, unlike other approaches, requires neither familiarity with nor solution of the partial differential equation(s). In this study, the model consists of two linear algebraic equations that are used to calculate the dynamic changes in forces and velocities along the rod. Practical usefulness of the proposed approach is shown by solving simple examples and by generating dynamometer cards for conventional pumping units. The computer-generated cards are compared to the cards actually recorded on the pumping wells simulated by the method. This study shows that the proposed approach is very efficient for designing and predicting the performance of a sucker rod pumping system.