| 摘要 |
The sub, usable as a length of drill string which may include a drilling motor body, includes three generally tubular members and an indicator ring. Two of the members have tool joint boxes with straight threads one threaded onto each end of a double ended tool joint pin. The pin has no shoulder but has an annular ring separating the faces of the boxes. The annular ring is keyed to the pin but is free to move axially some distance. One end of the pin and the mating box has coarser threads than the opposite end and the mating box threads. Before the assembly is torqued up for field use the pin may be rotated in the boxes by turning the ring. As the ring turns the finer threaded box has to turn faster in the same direction to maintain contact between all faces. This changes the rotational relationship between opposite ends of the sub and provides control of rotational orientation of opposite ends of an attached drill string. For use as a deflection sub the axes of the pin and all associated threads are tilted relative to axes of the the opposite end menders of the sub. When the pin is rotated in the boxes the same thing happens as described above but the axis of end members rotated on the stationary pin describe a cone. The rotation can be stopped at any end-to-end deflection from a straight condition up to twice the angle between pin axis and end axes.
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