The ability of a sucker rod to last in a well lifted with beam pumped equipment depends on many factors. One of the principle factors is the fatigue life of the rod. Previous rod life expectations are based on the modified Goodman Diagram that resulted in the expected life of approximately 10 million cycles. These expectations are based on fatigue work that is approximately fifty years old. This paper will discuss the major factors that affect fatigue life, the improvements in the quality and manufacturing processing of rods, and the use of other stress range diagrams over the last number of years. These combined factors have now resulted in the expected fatigue life of steel sucker rods of approximately 50 million cycles. Additionally, discussed in this paper are the application of fatigue life for used steel sucker rods and the development of new allowable stress curves for used rods.
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Hein et al. (1993) studied this question.