Orca Offshore has worked for the oil terminal owner to perform a generic mooring analysis for a range of vessel from 5,000 to 350,000 Ton DWT for their four terminals at the Bahamas to determine the allowable safe environment for the transfer operation. Two mooring locations are situated offshore while the other two are inshore sheltered in port.
The applied environment has been characterized by a directional Wind velocity table with associated wave heights based on the supplied Metocean report. The analysis considered the actual mooring arrangement and fender lay-out, all with the correct stiffness, and used frequency domain dynamic analysis to find the static and dynamic loads in the lines and mooring components. The analysis found the highest allowable wind velocity condition per compass direction in compliance with the allowable loads of the Berth and vessel components. The analysis also considered a high and a low draft of the vessels in combination with high and low tide levels. The moorings have been setup following the OCIMF guidelines and has used the environmental load coefficients as specified in these guidelines.
The result of the mooring analysis is a set of capacity polar plots showing the mooring wind velocity capacity per heading.
The scope of work for Orca Offshore included;
- Modelling of nine (9) tankers ranging from 5,000 to 350,000 ton DWT
- Modelling of the offshore and inshore berths
- Designing and analysis 32 mooring arrangements each at two drafts
The moorings have been analyzed using MOSES from Bentley utilizing the Orca Offshore developed analysis procedures.
