Catenary Anchor Leg Moorings (CALM) buoys are offshore structures that have been used for offloading, loading and discharge purposes. In this study, dynamic analysis is carried out on the submarine hoses attached to a CALM buoy and moored by six mooring lines in a water depth of 23.0m. Two submarine hose-strings in Chinese-lantern configuration are attached underneath the buoy. Three environmental conditions are considered, representing West Africa Sea, North Sea and Gulf of Mexico (GoM), respectively. Hydrodynamic simulation using ANSYS AQWA is first conducted to determine response amplitude operators (RAOs) of the buoy. Coupled dynamic models, where both buoys and hoses are included, are developed using Orcaflex. Parametric studies are conducted to investigate the effects of hose hydrodynamic loads and flow angles on the structural behaviour of the hoses, including bending moments, effective tension and minimum bend radius. From the study, a guidance dynamic amplitude factor of 2.0 considering hydrodynamic loads on hose DAFhose is proposed.

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There has been an increase in the application of composite structures in the oil and gas industry over the past four decades. This is due to more technological advancement and an increase in demand for the oil and gas. This trend has led to offshore exploration to transit from shallow water to deep water operations. Thus the need for more lightweight composite structures to reduce the deck loads and enable ease of operation. Composite risers are important as the properties of composite materials can be harnessed to improve riser performance and weight. This will enhance the development of deep water hydrocarbon reservoirs. In this paper, numerical stress analysis of composite offshore risers for deep water applications is carried out. ANSYS ACP is used for the finite element modelling of the composite riser for six load cases. From the design, recommendations for the design of the composite riser are made.

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The application of mathematical analysis has been an essential tool applied on Catenary Anchor Leg Mooring (CALM) buoys, Wave Energy Converters (WEC), point absorber buoys, and various single point mooring (SPM) systems. This enables having mathematical models for bonded marine hoses on SPM systems with application with CALM buoys, which are obviously a requisite for the techno-economic design and operation of these floating structures. Hose models (HM) and mooring models (MM) are utilized on a variety of applications such as SPARs, Semisubmersibles, WECs and CALM buoys. CALM buoys are an application of SPM systems. The goal of this review is to address the subject of marine hoses from mathematical modeling and operational views. To correctly reproduce the behavior of bonded marine hoses, including nonlinear dynamics, and to study their performance, accurate mathematical models are required. The paper gives an overview of the statics and dynamics of offshore/marine hoses. The reviews on marine hose behavior are conducted based on theoretical, numerical, and experimental investigations. The review also covers challenges encountered in hose installation, connection, and hang-off operations. State-of-the-art, developments and recent innovations in mooring applications for SURP (subsea umbilicals, risers, and pipelines) are presented. Finally, this study details the relevant materials that are utilized in hoses and mooring implementations. Some conclusions and recommendations are presented based on this review.

Due to the demand for oil production in varying water depth regions, the advantage of flexible buoyant conduits has led to an increase in bonded marine hoses for fluid transfer and (un)loading operations. The fluid transfer system for bonded marine hoses is dependent on floating offshore structures (FOS). This paper presents an overview of different systems for sustainable fluid transfer and (un)loading operations via FOS, such as Single Point Mooring (SPM) systems. SPMs are component aspects of the techno-economic design and FOS operation. This review aims to present sustainable fluid transfer technologies while addressing the subject of bonded marine hoses based on application, configuration, test models, hose selection criteria, hose-mooring configurations and operational views. This paper also includes an overview of the hose dynamics, with the loading and unloading (or discharging) techniques for sustainable fluid transfer via marine bonded hoses, based on operational challenges encountered. To dynamically present the hose performance in this review, an overview of the test methods’ guidance as specified in available industry standards was conducted. The pros and cons of marine hose application were also presented. Finally, this study presents different marine hose types and novel design configurations applied in implementing hose-mooring systems. Some concluding remarks with recommended solutions on the technology were presented in this review.

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