Analysis on the Critical Conditions of Side-by-Side Offloading Operation between SSP Type-FPSO and Shuttle Tanker

Abstract:

Evaluation is carried out on the operability of a 87,900 ton Sevan Stabilized Platform (SSP) functioned as an FPSO in the hypothetical operational site of Masela Block. This is to observe the critical conditions when side-by-side (SBS) offloading is performed between the SSP and a 35,000 DWT shuttle tanker. The first stage of analysis conducted on the moored SSP as a single floating body indicates the capability to withstand a 100-year wave, designated by the significant height of 8.0 m. Largest motions are experienced when SSP contains 75% load capacity, resulting in the mooring tension range from 2,000 kN up to 7,000 kN, portraying ample safety factors of 2.0 up to 3.0. The second stage of analysis is conducted for execution of SBS offloading from SSP to shuttle tanker, positioned in a 3.3 m distance. Observation is made when SSP is loaded with 100%, 83%, and 75% capacities correlated to the shuttle tanker loading of 10%, 60%, and 90% capacities. This reveals critical conditions arise when the wave exceeds 2.0 m in height, or the operability level of some 88.5%. Safer operation and higher operability level could be achieved by increasing the distance of SSP and shuttle tanker.

• Periodical: Applied Mechanics and Materials (Volume 874)
• Pages: 53-63
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.874.53
• Online since: January 2018
• Authors: Murdjito Murdjito*, Maria Putri Rosari, Eko Budi Djatmiko
• Keywords: Motion Responses, Operability, SBS-Offloading, SSP Type-FPSO, Tension

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