无驴头增程抽油机设计及分析

Design and Analysis of Non-Horsehead Beam Pumping Unit

常规游梁式抽油机采用驴头与钢丝绳将曲柄摇杆机构产生的圆弧曲线变为直线,满足了抽油机工作要求。本文设计了一种无驴头增程抽油机,其特点是取消了驴头,在传统的游梁式抽油机上增加了辅助直线机构。根据该抽油机的结构特点,对其建立了数学模型,并用解析法求出了悬点位移、速度、加速度曲线。研究了辅助机构长杆、短杆长度对抽油机冲程和尺寸的影响,为无驴头增程抽油机的优化设计提供了参考。利用有限元软件对其关键部件进行力学分析,并在满足安全要求下进行拓扑优化,降低了生产成本,提高了经济效益。

The circular arc is formed by the crank rocker mechanism, the horsehead is adapted to change the circular arc into a line in conventional beam pumping unit, thus could meet the motion performance needs of beam pumping unit. The reliability of the conventional beam pumping unit, however, is reduced due to the installation of horsehead and wire rope. By applying the auxiliary linear mechanism （ALM） , which replaced the horsehead, a new non-horsehead beam pumping unit is designed in this paper. Based on the structural characteristics of the new pumping unit, the mathematical model is established, and the polished rod load displacement, velocity, acceleration curve are calculated by using the analytic method. The influences of long rod and short rod of the ALM on stoke and size of the beam pumping unit are studied, which provide reference for optimi- zation design of the new non-horsehead beam pumping unit. Mechanical analysis on the key parts is conducted by using the finite element software, and the topological optimization is also processed with the satisfactory in security requirements, thus it could reduce the production cost and improve the economic benefit.