| 摘要 |
A lifting gear 1 for lifting tubular elements comprises a central unit 2 having a number of gripping arms 3 which project radially therefrom and are pivotable in their respective axial plane and which are thereby matched to all sizes of tubular element to be lifted by means of the gear 1, the ends of the gripping arms 3, when the gear 1 is lowered into a tubular element, dragging against the inner wall of the element and, when the latter is lifted, being squeezed against this wall into engagement therewith and adopting a position leaning obliquely upwards against the wall. A compression spring 8 is inserted between a spring stop 7 at the lower end of a pull rod 5, at the upper end of which there are members 6 for attachment to a lifting cable or equivalent, and an end wall 10 to an inner sleeve 9 surrounding the compression spring 8. A number of wings 13, one for each gripping arm 3, project radially out from the inner sleeve 9. An arm 29 extends between each wing 13 and each gripping arm 3 and is articulately attached to these. The gripping arms 3 are articulately attached to an outer sleeve 16 which surrounds the inner sleeve 9 and has an upper end wall 17 through which the pull rod 5 is displaceably disposed. A locking stop 12, which is attached to the pull rod 5, is placed between the upper wall 10 of the inner sleeve 9 and the upper wall 17 of the outer sleeve 16. A locking tongue 20 is arranged in pretensioned condition to slide in to a locking position beneath the locking stop 12 when this is adjacent to the upper end wall 17 of the outer sleeve 16. An intermediate sleeve 14 is disposed between the inner sleeve 9 and the outer sleeve 16 such that it is displaceable between a lower, inactive position and an upper position in which it disengages the locking tongue 20 from the locking stop 12. <IMAGE> |
