Theories And Experiment Research On Pumping Units With Secondary Balancer

Because of simple and reliable, the pumping units are still playing the leading role in the sucker rod pumping oil production equipments. According to statistics, about a third of oil field produce cost is power consumption, in which the beam-pumping units cost takes up 80%. The major cause of big power consumption is high installed power and low average electric motor work efficiency, which is caused by hugely fluctuation of reduction gearbox output torque. So reducing the fluctuation is of greatest importance to oil field energy-efficient production.Making the pumping units motion analytical models is based on basic structure of the pumping units to analyse the motion law of polished rod, reduction gearbox output torque and electric motor performance characteristic, and find out the major cause of low electric motor work efficiency.According to fourier series, the pumping units delicate balance theory built. The paper seted up the pumping units secondary balancer design ideas, which included the appliance design decision and structural design, structural parameters design analysis, the pumping units secondary balancer calculator program and the secondary balancer structural parameters optimization design to different types of pumping units.The secondary balancer appliances have been installed on three wells in the oilfield. The field test is carried on based on secondary balancer parameters design analysis. It turned out that secondary balancer appliances could effectively decrease reduction gearbox output torque fluctuations and improve the electric motor work efficiency. The root-mean-square torque has a decrease of 23.8 percents, meanwhile the average electric motor work efficiency has a increase of 29.8 percent. Theoretical result is in good agreement with experimental results, so it shows the secondary balancer calculation is accurate.