John H. Day, Jr., General Electric Company
The use of electric motors as prime movers for driving oil well pumping units is well established today. In fact, reliable estimates now indicate that a sizeable majority of new oil wells going on artificial lift are being powered by electric motors. With the tremendous increase in the use of electrified oil well pumping, many operators are examining their horsepower sizing and application formulae more closely than ever in using electric motors to drive beam pumping units. Field tests, for example, generally have shown that most electrified wells are over-motored and that economy of operation, as well as lower first cost, could be realized with a proper sizing of the motor to the load. Also, there is the question of which type of motor should be selected. There is general interest in the industry today in the evaluation and advantages in the performance of various design types of oil well pumping motors.