Finite Element Analysis of Spreader Bar by Utilizing the Arrangement and Connection of Padeyes

che zaid zakaria, Nuraini Abdul Aziz

Abstract


Heavy lifting is one of several methods used for marine installation of heavy equipment while spreader bar (SB) is widely used in heavy lifting. The application of SB is mainly to avoid an overstress in the structure when being lifts which due to sling arrangement in bridle. SB is typically made of high strength tubular pipe with padeye/trunnion attached. Comparison between 3 types of padeye arrangements on SB is made based on its strength properties as reflected in API RP 2A 22nd edition to ensure its optimum design centred on material’s weight and welding work criteria. The buckling load for lightest pipe among 3 types of SB is then calculated. Finite element analysis (FEA) is performed to verify design stresses and buckling load of selected pipe. From observation, the thickness of tubular pipe can be reduced up to 50 percent compared to other SB types by setting the centre line (CL) of upper padeye to be in line with tubular pipe axis.


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