| 摘要 |
A ship's derrick can be swiveled and tripped up by means of a goose-neck pin-bearing and one or more topping lift tackles. Its tackle is fastened to a crab which can be moved in the longitudinal direction of the derrick by means of a tackle line. In the case of a heavy cargo derrick, the tackle line between the derrick brace and the crab comprises a multi-part tackle which may be cut and dimensioned similar to the load tackle and which is provided with two hauling parts, the arrangement being such that the topping lift tackles act on the crab.
|
