| 摘要 |
A well pump includes a string of risers composed of a plurality of releasably coupled risers, a hollow upright, and a drive mechanism releasably mounted on the upright. The corresponding erecting rig consists of a mast adapted to be supported by the upright, a deflecting device arranged at the upper end of the mast, and a pulling element passing around the deflecting device and formed at its one end for suspension of a riser and at its other end for suspension of a lifting device. The erecting rig is much lighter in weight and simpler and, therefore, may be transported and assembled more easily than lifting tackle used so far of the same lifting height and capacity. |
