Study On Electric Submersible Pump Eccentric Wear Failure Mechanism And Countermeasures

The Electric submersible pump as one of the main lifting method in Sheng Tuo oilfield, which has the features of high head, large discharge capacity, is difficult to substitute by other production equipment. With the development of Sheng Tuo oilfield entered ultra-high water cut stage, the well condition becomes deteriorating and complex, electric submersible pump also appeared a series of inadaptation, in which the phenomenon of the pump and shaft eccentric wear performance more prominent. These phenomena mainly occurred in the small capacity electric pump well of 150 party, especially in the second half of 2010. This paper starts from influence factors of the eccentric wear of electric submersible pump shaft, tracks anatomical unit phenomenon, analyses on the characteristics of the failure point, studies the mechanism of the pump shaft eccentric wear mechanism, thus propose the corresponding five countermeasures, including changing the blade wheel structure, increasing the number of the hard alloy centering bearing, optimizing centralizer bearing location, changing the thrust washer material and thickness,and the use with cyclone desander. The modified 150 party electric pump unit stability improved greatly, strengthening effect is enhanced, vibration characteristics in the process of operation is reduced, all the indicators have significantly improved. By experimental verification,vibration indicators improve significantly, field application effect is good, achieved the desired effect. After the application of 100 wells, the average pump detection extend to period of 325 days, get a good application effect.