Feasibility Studies on Offshore Triceratops as Future Offshore Structure Using FMEA Approach

Abstract

As future drilling and exploration moves towards ultra-deeper waters, the interplay between offshore structures and the sea environment as well as lessons learnt from previous offshore accidents have been challenging for oil and gas professionals whose cravings for crude oil remains persistence in spite of all these challenges. These has necessitated the need for durable and reliable offshore structure(s) that will mitigate this challenges without compromising the potentials of exiting offshore structures as water depth varies from location to location. Comparing the characteristics of various offshore structures in this study, offshore triceratops is a recent innovation that combines the major characteristics of TLPs and Spars for ultra-deep water oil exploration. It is composed of deck structure that seats on three buoyant leg structures (BLS) linked together by ball joints. These joints make the structure a stable and heave restrained system where pitch and roll motion is absent with minimal level of surge and sway during operation. The three BLS structures are anchored to the seabed via mooring lines. Using FMEA methodology to assess the durability and reliability of the functional parts of offshore Triceratops in this study, the result shows that ball joint has the highest risk priority number of 70 due to effects of fatigue, corrosion, and bending and axial compression on the ball joints. Thus, the possibility of failure is high if strict design attention is not focused on the ball joint.