ANALYSIS OF APPLICATION RESULTS OF LONG STROKE PUMPING UNIT

The indexes to judge production status of long stroke sucker rod pumping well such as energy conservation,pump efficiency and system efficiency etc.have been analysed and studied by other authors,but those indexes cannot represent all-sidely the effectiveness of long stroke pumping unit.Based on the systematical analysis and discussion on the pumping effectiveness of pumping unit,this paper expounds the four special features of long stroke pumping unit compared with.conventional unit:(1) it may lower the elastic deformation of sucker rod and tubing,reduce the stroke loss,increase the coefficient of fillness,decrease the leakage,and then enhance the pumping efficiency;(2) it may improve the working conditions of downhole pump,decrease the fault,extend the free of maintenance period;(3) it may improve the working performance of pumping unit,prolong the operating life;(4) it may reduce the energy consumption,increase the system efficiency.Therefore,long stroke pumping unit has a wide developing prospect.