| 摘要 |
A boom point construction connects the for and aft mountings of a sheave swivel to the major structural elements of a boom. The boom point includes a framework of elongated members joined together to form a truss. The framework includes assemblies of at least three members joined together at one common point and extending in different directions from the point to define three different planes. Two of the assemblies extend from opposite sides of the front swivel support and another of the assemblies extends from the rear swivel support. A member of the assemblies from the front swivel support is connected to members of the assembly extending from the rear swivel support. The boom point is shown connecting the swivel to a boom having either three or four major longitudinal structural elements. |
