Preface
Deepwater flexible risers and pipelines are challenges for deepwater oil and gas productions. This is particularly important when we use FPSO and semi-submersible solutions. In the Gulf of Mexico, deepwater flexible risers and pipelines are also widely used for tie-in of new production wells and manifolds to existing production systems such as TLPs and Spars, etc.
The author has been fortunately involved with deepwater flexible risers and pipelines projects when he was working in the USA and Norway. In the past 15 years, he has been engaged in research and consulting of relevant subjects. This book summarizes his work in four different subject areas:
Part I deals with mechanics of deepwater risers where our focus is cross-section design of the risers under combined loads. We derived formulation for strength analysis of deepwater flexible pipes under internal pressure, external pressure, tension, torsion, and bending curvatures. We also address strength of the pipe during coiling, installation, and possible failure during the process.
Part II addresses global response of the riser systems in deepwater. We derived formulations for static configuration design and dynamic response. This is particularly important for global configuration design in static and dynamic environment.
Part III is devoted to a new kind of flexible pipe that is made of fiberglass material. We derived formations for pipes under internal pressure, external pressure, tension, bending, and torsion.
Part IV summarizes experience we have for ancillary equipment design. This is mainly for riser hang-off locations and touch down areas. We address the design of bending stiffeners, bend restrictors and connectors. Riser connectors are perhaps the single most critical element in the safety and integrity of the riser and pipeline systems.
We wish that this book will be a useful reference source of flexible risers and pipelines design and analysis for subsea engineers. This book mainly considers deepwater water applications. For shallow applications, we recommend our book “Flexible Pipelines and Power Cables”. For cross-sectional design, we recommend our book entitled “Flexible Pipes”. All three books are published by Scrivener Publishing and Wiley.
Acknowledgment
The authors would like to appreciate Prof. Yong Bai’s graduate students and post-doctoral fellows at Zhejiang University who provided the initial technical writing for Chapters 2, 3, and 4 (Fancesco Cornacchia, Qiangqiang Shao, and Dr. Ting Liu), Chapter 6 (Dr. Yutian Lu), Chapter 7 (Dr. Yuxin Xu and Dr. Pan Fang). Chapters 9 to 11 (Dr. Weidong Ruan), Chapters 12 and 13 (Dr. DaPeng Zhang), Chapters 14 (Dr. KA Jiamg), Chapters 17 and 18 (Dr. Wei Qin), Chapter 19 (Dr. XiaoJie Zhang), Chapter 20 (Dr. Shanying Lin), Chapter 21 (Dr. Yuxin Xu), Chapter 22 (Dr. Yifan Gao), Chapter 23 (Ms. Xinyu Sun), Chapter 24 (Dr. Mohsen Saneian), Chapters 25 to 26 (Dr. Wei Qin) Chapter 29 (Dr. Zhao Wamg). Thanks to all persons involved in reviewing this book. The authors also would like to thank the flexible pipe manufacturing company OPR Inc. for their support for publishing this book.
The author is grateful to Ms. Xin Zhou who provided editorial assistance. I am thankful to Martin Scrivener and Phillip Carmical of the Scrivener Publishing and Wiley.
Prof. Yong Bai June 01, 2020
About the Author
Professor Yong Bai is the president of Offshore Pipelines and Risers Inc. and also the director of the Offshore Engineering Research Center at Zhejiang University. He has previously taught at the University of Stavanger in Norway where he was a professor of offshore structures. He has also worked with ABS as manager of the Offshore Technology Department and DNV as a JIP project manager.
Professor Yong Bai has also worked for Shell International E&P as a staff engineer. Through working at JP Kenny as manager of advanced engineering and at MCS as vice president of engineering, he has contributed to the advancement of methods and tools for the design and analysis of subsea pipelines and risers.
Professor Bai is the author of approximately 10 books such as “Marine Structural Design” and “Subsea Pipelines and Risers”. He authored more than 100 SCI and EI papers on the design and installation of subsea pipelines and risers.
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Introduction
1.1 Flexible Pipelines Overview
The oil and gas industry proclaims pipelines as the most economical device of large scale overland conveyance for crude oil and natural gas, compared to truck and rail transportation. These can continuously carry large quantities of fluids and they are considered by far to be the most reliable. The rapid development of the petroleum industry leads to high financial investments in engineering research, which has quickly conducted to achievement of remarkable effects, so that recently steel homogeneous pipes have been replaced by flexible pipelines, widely used by oil and gas industry for both onshore and offshore purposes. Mostly, they are employed offshore as transportation of well products such as oil, gas, and condensate, well control lines, injection of water and gases, and export of processed product, but also as flowlines connecting subsea wells, well-head platforms, templates or loading terminals, processing platforms, and jumper lines connecting fixed platforms to support vessels.
Flexible pipelines are relatively new kinds of profiles which have developed since the late 1970s; initially, they were used in few offshore areas until being employed in many projects, thanks to the applicability in water depths up to 8,000 ft, pressures up to 10,000 psi, and high temperatures up to 150°, beside the high adaptability to different environmental conditions and large vessels motion [1].
