摘要 |
A well assembly including a drive string, a frame, a spindle mounted on the frame and means for rotating the spindle, is constructed to allow the upper end of the string to pass through the spindle. A nut with a non-circular downward protuberance is tightly, threadably engaged with the upper end of the drive stung. The spindle has a non-circular upward protuberance, and a tail bar snugly receives both protuberances. The tail bar supports the weight of the string and transmits rotary torque from the spindle to the string.
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