Trunnions tailing

At the initial pick point, when the vessel is still horizontal, the load is shared between the lifting lugs and the tail beam or lug, based on their respective distances to the vessel c enter of gravity. As the lift proceeds, a greater percentage of the load is shifted to the top lugs or trunnions until the vessel is vertical and all of the load is then on the top lugs. At this point the tail beam or shackle can be removed. 

Trunnions may be used as tailing devices as long as the resulting local loads in the sldrt are analyzed. 

Case 4 Cone Lug or Trunnion with Intermediate Skirt Tail... 

When a stack or vessel is lifted, various loads are imposed on the lift devices (lifting lug, tail lug, or trunnions) over the various values of the lift angle, 9. To assess these stresses, Chapter H ( Combined Stresses ) of the AISC Manual [3] combines axial tension and bending, illustrated in paragraph H2 in Equation H2-1, as follows ... 

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