Lynn Rowlan, Echometer Company, Norman Hein, Oil & Gas Optimization Specialist, Ltd
During recent sucker rod pumping problem solving schools it has become apparent that few engineers and operators know about the non-dimensional pumping parameters developed by the Sucker Rod Pumping Research Inc. and provided to the industry in API RP 11L for rod string designs. This paper will discuss the background and physical meaning of the two main parameters Fo/SKr and No/No", show the nomograph of their inter-relationship, and provide recommended limits which are typically not provided in modern rod string computer programs. These limits may assist in reducing sucker rod system failures. Additionally, the relationship of these design parameters to the dynamic motion of the sucker rod pumping system and the formation of undertravel or overtravel dynamometer cards will be provided.