Dynamic Characteristics Research Of Sucker-rod Pumping System With Load Reducer

Rod pumping is a traditional mechanical recovery mode, also in the dominant position.With the time extension of oilfield exploitation, the reservoir of deep buried、low formationenergy、poor permeability、bad water injection effect is used more and more. The exploitationof this kind reservoir mainly uses the method of small pump depth-pumping. The existingtechnology of small pump depth-pumping is restricted by polished rod load rating of thepumping unit, as also as sucker rod quality. Then pump depth is restricted in some degree,difficult to meet the need of oilfield development.Load reducer is a subsurface tool in the oil well. The load reducer can reduce sucker rodstress and polished rod load of pumping unit horse head by hydraulic pressure. Also canreduce energy consumption，solve the existing equipment problems of shortage polished rodload rating and overweight sucker rod column.Because the lightening force produced by the load reducer, the dynamic characteristicsand the balance of sucker-rod pumping system are changed. For pumping unit, the quality ofthe balance directly influences the speed reducer、motor load service life and the operation ofthe stability. So with load reducer, the sucker-rod pumping system needs to adjust the balanceand sucker rod column needs to optimization design and rational configuration. This paperintroduced the load reducer working principle and application first. Combining sucker rodcolumn with load reducer get the design and calculation method. Then using the finiteanalysis software——ANSYS simulate multilevel sucker rod column dynamic process. Showthe whole sucker rod column dynamic characteristics accurately. Finally, according to thesystem movement rules and the balance principle, research the sucker-rod pumping systemwith load reducer. The theoretical calculation combining with the actual working condition，get the new balance parameters suitable for the application through the numerical analysis andcalculation results. Adjust the system balance and analysis dynamic characteristics, make thepumping unit work in equilibrium state, to achieve the purpose of saving energy and reducingconsumption.