OPTIMIZATION OF PARAMETERS FOR MULTI-STAGE SUCKER ROD OF UNIFORM STRENGTH

In view of the working conditions of the long stroke pumping unit in deep wells, the movement characteristics of the sucker rod are analyzed, and formulae are derived to calculate the stress and extension of the multiple-stage sucker rod and the effective stroke length of rod pumping units. Based on these formulae and the uniform strength principle of sucker rod, some key geometric parameters such as length and diameter for the multi-stage sucker rod are optimized.