Research on mechanical characteristics and safety of working platform in rod pumping process

Rod pumping on offshore platform provides a solution to low efficient extraction of offshore heavy oil and the safety of working platform is the prerequisite for the implementation of this new technology. In this paper, a coupling dynamics model of rod pumping system and the jacket platform is established, and the dynamic characteristics of the pumping unit excitation, rod pumping system, and jacket platform is studied. Based on the analysis of the multi-body dynamics model, the three frequencies (pumping unit excitation, rod pumping system, jacket platform) are far apart, so the dynamic effect of rod pumping on the platform can be analyzed according to static load. Based on the limit working state and the cumulative damage theory of the structure, the safety evaluation standard for the increased load of the jacket platform is established. Under the extreme marine environment once in 50 years, the safety factor of the main structure of the platform is greater than 4, and the overall safety factor is 3% lower than that before the rod pumping operation. Offshore rod pumping has less influence on the jacket platform from analysis, and which lays a theoretical and safety foundation for offshore oil pumping.