潜油直线电机无杆举升技术在定向井中的应用

Application of Submersible Linear Motor in Directional Well

应用大平台开发低渗透油藏已经越来越普遍,然而井眼轨迹复杂和液量低是这类油田的特点,采用抽油机有杆举升存在偏磨及系统效率提升有限的问题,而采用无杆举升技术时又存在一次性投资高及免修期短的问题。为此,开展了以一台直线电机同时驱动上、下两台柱塞泵的潜油直线电机无杆举升技术研究,对系统的水力学参数进行了计算,对直线电机的型式、永磁材料进行了选择,并对系统管柱进行了现场试验。试验结果表明:研制的潜油直线电机外径104 mm,稳定举升力达12 kN,满足低液量油井的举升要求;应用潜油直线电机无杆举升系统提高了系统效率,降低了能耗,从根本上解决了杆管偏磨问题,免修期达到411 d。潜油直线电机无杆举升技术为低液量油田提高系统效益提供了新方法。

It is more and more common to use large well pad to produce low-permeability reservoir.However,the complex deep well trajectory and low liquid volume are the characteristics of such oilfields.The use of rod pumping system has the problem of rod eccentric wear and limited system efficiency improvement.The rodless lifting technology has the problems of high one-time investment and short maintenance period.To address the problems,a new technology was investigated,namely the submersible linear motor rodless lifting technology which uses one submersible linear motor simultaneously driving upper and lower plunger pumps.The hydraulic parameters of the system were calculated.The type of the linear motor and permanent magnet material were selected.The system string was tested onsite,and the results showed that the developed submersible linear motor with the outer diameter of 104 mm provided a stable lifting force of 12 kN,which met the lifting requirements of low-liquid volume oil wells.The application of the submersible linear motor rodless lifting system improved system efficiency and reduced energy consumption and addressed the problem of eccentric wear,resulting in maintenance-free period of 411days.The investigation provides a new method for improving the system efficiency of low liquid oil wells.