In this instance the boom foot nodes were restrained in x, y planes for rotation thus acting as a pivot point.

The models were created in SpaceGass by positioning spatial nodes representing structural intersections and connecting them with beam elements representing the actual section sizes and properties of the members used. The HRB numbers were converted to the steel tensile strength.Ī 3-dimensional model of the boom structure was created was modelled according to the geometry and properties detailed on the reference drawings and engineering documentation. Prior to the structural modelling and analysis, a crane inspection and Hardness tests and dimension inspection for the steel sections was conducted on site to obtain Rockwell B number (HRB). Pressure Dynamics was engaged by the client to conduct an analysis of the structural effects of damage identified during a prior inspection on the offshore pedestal crane, to determine whether the Safe Working Load (SWL) specified in its load chart needed to be de-rated. The client achieved confidence in ongoing lift operations and confirmed operational compliance for the asset and facility Pressure Dynamics further recommended monitoring, maintenance and operational management actions, supporting scheduled and cost-effective maintenance planning. It was found that although the physical damage to the crane boom members increases the maximum utilisation of the boom, it was still within the allowable limits of AISC requirement. SpaceGass analysis results were checked against AISC ASD for structural utilization, and also against AS4100. Pressure Dynamics created a 3-dimensional model of the boom with reference to reference drawings and engineering documentation.ĭesign loads were determined according to API 2C 7th Edition, and with reference to sea conditions and combined input factors. Damage to structural members of an offshore pedestal crane boom was identified during an inspection.Ĭlient required a structural analysis to assess physical damage to the crane boom members identified, and determine whether the Safe Working Load (SWL) of the crane needed to be de-rated.

Pedestal crane lifting chart