S.G. Gibbs, Nabla Corp.
Although it looks simple, rod pumping equipment requires complex simulation methods to mimic the variety of actual conditions encountered in the field. This paper describes such a method which relates the influence of unit geometry, prime mover slip, rod design and downhole pump condition. The method is mathematical, but non-technical means such as dynamometer cards and electrical terms are used to describe it. The intent of the paper is to study a variety of practical rod pumping questions that frequently arise. It has been found that the computer aided simulation has suggested performance phenomena not widely known or understood. Portions of the subject method have been under development for twenty years. Some of the theoretical details are shown in Reference 1. Recent additions to the technology have been in handling the effects of inertia on gearbox and prime mover loading (Ref. 4). Most recent has been simulation of electrical performance of motors.