Engineering & Drilling Machinery As

John Daniel Madsen

Bj&oslash;rn Eilertsen

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 ( ), a storage guide rail ( ) parallel thereto, and in a lower portion of the derrick a connecting guide portion ( ) between the two said rails, a rack ( ) are slidably arranged in each guideway which racks ( ) are divided into successive, preferably hingedly interconnected rack segments ( ) designed to bear against one another when the rack ( ) or when a part thereof is in the vertical main guide rail ( ) the main guide rail ( ) being designed for horizontal support of the rack segment ( ), a load-being yoke ( ) supported on the rack ( ) in the respective vertical main guide rails ( ), and a driving gear ( ) including a driving gearwheel ( ) in driving engagement with the rack ( ), in the respective vertical guide rails ( ).

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Sandnes, Norway

John Daniel Madsen