In the light of the frequent breaking of the rod string in a surface driven screw pump well, the force condition of the string in the well is analyzed by means of the elastoplasticity theory.

• 针对井口驱动螺杆泵抽油杆柱断脱频繁的问题，应用弹塑性理论分析了抽油杆柱在井中的受力状况。