FAQ >> Column Derrick

Column Derrick

A column derrick is a modified guy derrick that is useful where loads must be lifted to a building setback or penthouse Instead of guys, a structural frame is installed at the mast top spider and is attached to building columns or other substantial bracing means (Figure 2.7 . The frame acts as a rigid mast support system as opposed to the guys ordinarily used, because guys are somewhat slack, a guyed mast will lean toward the boom as a load is lifted. A column derrick can be installed at locations where space is limited or where there is not sufficient space or clearance for a full set of guys. But there must be an adjacent structure high enough for attachment of the top frame. A column derrick can swing freely since there are no guys in the way, and it is not necessary to utilize that time- consuming maneuver of booming-in and ducking under the guys.

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