全平衡带式长冲程抽油机辅助换向装置

Mechanical reversing device for full balanced belt pumping unit.

针对以电动机换向的全平衡带式长冲程抽油机存在电动机启动频繁和启动电流过大的缺点 ,设计了一种机械制动辅助换向装置 ,通过能量转换和形成力差 ,实现全平衡带式长冲程抽油机运动的自动换向 ,使电动机正反转都能在空载下启动 ,接近额定转速后承载运行 ,从而有效地降低电动机的启动电流峰值和输出功率。介绍了这种换向装置的结构和工作原理 ,并对制动过渡过程的行程、机械制动与辅助换向装置的传动比、扭簧的刚度、工作转角和结构参数做了分析计算。现场试验结果表明 ,增设机械辅助换向装置的长冲程抽油机节能和增产效果显著 ,比原来安装于框架上的缓冲限位器结构简单 ,工作可靠 。

The full balanced belt long stroke pumping unit has the shortcoming of frequent motor starting with large current. A mechanical braking and auxiliary reversing device is developed for the automatic resersing of the pumping unit. By means of energy transformation and forming difference of force, the device can realize the starting of the electric motor under zero load and loading at the speed closing to the rated speed, thereby reduces effectively the peak starting current and power output of the motor. The structure of the device is described, and the trip of the rod string during braking, the transmission ratio of the reversing device, and the rigidity and corner and structural parameters of the torsion spring are calculated and analyzed. Field test shows that the long stroke pumping unit with the reversing device has good operational performance.