Theoretical analysis of reinforcement layers in bonded flexible marine hose under internal pressure


Offshore field engineering and technology have advanced immensely over the past few decades. The sector involves numerous activities including oil and gas exploration and extraction, offshore mining as well as sea transportation of minerals. For instance, the bonded flexible marine hose has been widely used in connecting platforms to oil tankers to enable oil transfer. Generally, a housing assembly comprises of vulcanized rubber, reinforced fiber and steel fitting at the end. Unfortunately, marine hoses are susceptible to failures due to induced internal pressures and bending moments. To this note, feasible offshore systems with large flexibility are needed for efficient operations. This calls for the use of multi-layered marine hoses capable of withstanding the moments and pressure challenges.

Among the available marine hose layers, steel helical wire and reinforcement layers are very important. Reinforced layers are generally made of synthetic fibers comprising of winding angles in each of the layers. Thus, the composite layers have presented numerous advantages over the conventional structures. However, the problems associated with the bonded flexible marine hoses have not been fully explored regardless of the development of several guidelines for structural design. Consequently, less emphasis has also been given to the theoretical investigation of the marine hoses. According to the researcher, however, theoretical studies will overcome the mechanical complexity of the structures by focusing on the basic layers thus providing a reference base.

Recently Fudan University researchers: Dr. Young Zhou, Professor Menglan Duan and Dr. Jianmin Ma in collaboration with Dr. Guomin Sun at the Offshore Oil Engineering Company investigated the analysis of reinforced layers in bonded flexible marine hoses under internal pressure. They aimed at developing a theoretical solution to clarify the mechanical behaviors of the reinforcement layers and further presenting a mathematical approach for multi-layer composites of synthetic fibers in structures. Eventually, the feasibility and accuracy of the method were verified by comparing the results to those available in the literature. Their work is published in the research journal, Engineering Structures.

The authors observed that the method allowed for the determination of reinforcement fiber layers that could be used to provide the desired information for guidance during the design, optimization and verification of the marine hoses’ behaviors. Consequently, it was necessary to investigate parameter and failure analysis which produced distinctly new results due to the combination of the winding angles, internal pressure and the number of layers. For instance, an optimal winding angle of ± 55 was noted. Furthermore, the computational time was significantly reduced due to the use of the programming while the post-processed results could be easily and efficiently exported as compared to other techniques.

The study successfully developed a theoretical solution to clarify the mechanical behaviors of the reinforcement layers. Therefore, the obtained findings will form the fundamentals for future research work thus leading to more advancement of the offshore engineering filed and the related operations. Also, it will ensure the efficient design of marine hoses with increased lifespan.

Theoretical analysis of reinforcement layers in bonded flexible marine hose under internal pressure - Advances in Engineering Theoretical analysis of reinforcement layers in bonded flexible marine hose under internal pressure - Advances in Engineering

About the author

Dr.Yang Zhou received his undergraduate Bachelor’s degree in Mechanical Engineering from Southwest Petroleum University (Chengdu, Shanghai) in 2013. He then completed his Ph.D in Fluid dynamics from Fudan University (Shanghai, China) in 2018. During 2015 to 2017, he acted as a visiting student in Federal University of Rio de Janeiro (Rio de Janeiro, Brazil) and China University of Petroleum, Beijing (Beijing, China). Currently, he is a research associate at Research Institute of USV Engineering in Shanghai University (Shanghai, China).

His current research aims at understanding the mechanical behavior of flexible pipes and marine hoses with theoretical description in offshore engineering. His research interests also focus on music technology & computer music.

About the author

Professor Menglan Duan is now the Head and PhD Supervisor of Offshore Oil/Gas Research Centre at China University of Petroleum (Beijing). He graduated from Jianghan Petroleum College (merged to Yangtze University since 2003) with a Bachelor’s degree in Oil Drilling Engineering. Afterwards, he furthered his education at China University of Petroleum and obtained his Master’s degree in Oil Field Mechanical Engineering and PhD degree in Oil/Gas Mechanical Engineering respectively in March 1990 and July 1993. From August 1993 to August 1995, he did post-doctoral researches in Solid Mechanics at Institute of Mechanics under Chinese Academy of Sciences. Later on, he worked at China Classification Society (CCS) from September 1995 to June 2006.

During the 11 years at CCS, he was invited to do post-doctoral researches as Senior Visiting Scholar at University of Rochester in USA from March 1997 to April 1998. In the year 2002, he was appointed as Chief Engineer and Member of the Party Committee at CCS for four years. Since 2006, Professor Duan has been teaching and researching at University of Petroleum (Beijing).

His research interest: offshore oil engineering, subsea engineering, fatigue and fracture of materials and structures, random vibration and vibration reduction, sea ice engineering mechanics, as well as risk and reliability in offshore and ocean Engineering.


Zhou, Y., Duan, M., Ma, J., & Sun, G. (2018). Theoretical analysis of reinforcement layers in bonded flexible marine hose under internal pressure. Engineering Structures, 168, 384-398.

Go To Engineering Structures

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