摘要 |
A derrick, especially a drilling rig derrick, including a derrick structure and lifting tackle for a load, for example, a drill string, in the derrick structure. The lifting tackle includes guideways in parallel relation which each includes a vertical main guide rail (4, 7), a storage guide rail (5, 8) parallel thereto, and in a lower portion of the derrick a connecting guide portion (6, 9) between the two said rails, a rack (10, 11) are slidably arranged in each guideway which racks (10, 11) are divided into successive, preferably hingedly interconnected rack segments (12, 13) designed to bear against one another when the rack (10, 11) or when a part thereof is in the vertical main guide rail (4, 7) the main guide rail (4, 7) being designed for horizontal support of the rack segment (12, 13), a load-being yoke (22) supported on the rack (10, 11) in the respective vertical main guide rails (4, 7), and a driving gear (25) including a driving gearwheel (26, 27, 28) in driving engagement with the rack (12, 13), in the respective vertical guide rails (4, 7).
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