| 摘要 |
A portable apparatus for drilling deep boreholes in the earth, comprising a subbase structure, a drawworks platform supported on four legs hinged both to the subbase structure and to the drawworks platform and when in lowered position extends away from a first end of the subbase: A mast hinged to the sub-base structure by two legs and in the lowered position extends away from the second end of the sub-base; a pulling means has a sheave through which a slingline cable is passed, and the two ends of the cable are separately connected between the mast at a selected point, and a pulley mounted on the drawworks platform so that in one continuous pulling motion of the pulling means, the drawworks platform is first raised into vertical position, and then the mast is lifted until both parts are fully erected on the subbase.
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