双变径天轮式抽油机的选型分析

Pattern selection of dual variable-diameter wheel pumping unit

双变径天轮式抽油机由曲柄、连杆、摆杆、机架、柔性连接件、天轮和导向轮等组成。在天轮曲线选择设计中 ,前变径轮选用 3段圆弧连接曲线 ,后变径轮选用对数螺线 ,并根据模型示功图对天轮和整机的尺寸参数进行了优化设计。与同类型国内其它厂家产品性能对比及 2 0台改造样机的现场试验表明 ,这种天轮式抽油机运动、动力性能好 ,运转平稳 ,节能效果明显 ,其柔性连接件经过改进后寿命超过 1a。

The dual variable-diameter wheel pumping unit is comprised of crank arm, pitman, swing link, pumping jack, flexible connecting fittings, sheave pulley and guide wheel. In the design of the curve of the sheave pulley, the front varible-diameter wheel adopts 3-section circular arc and the rear wheel applies logarithmic spiral. And the dimensions of the sheave pulley and the pumping unit are optimized according to the dynamometer card of the model. Contrast analysis and field test show that this kind of pumping unit has reliable performance and obvious power-saving effect, and its connecting fittings modified can keep running for over a year.