ANALYSIS OF A CASE STUDY REGARDING THE OFFSHORE S-LAY INSTALLATION OF GAS PRODUCTION PIPELINE WITH A FOCUS TO THE CURRENT STATE-OF-THE-ART.

This master's thesis presents a cutting-edge case study analysis of offshore Sub sea S-lay installation techniques for a gas production pipeline. In the rapidly growing market of offshore energy extraction, it is important to adopt advanced installation techniques to ensure the reliability, efficiency, and safety of pipeline transportation systems. As the global energy landscape continues to evolve, the efficient and safe transportation of natural gas from offshore reservoirs to onshore facilities remains a crucial challenge. This study focuses on how to install gas pipelines from offshore gas fields to onshore facilities using the S-lay installation technique as a prime example of state of the art modern engineering. Against the backdrop of increasing demand for natural gas and the exploration of remote offshore fields, the case study explores the detailed steps of planning, executing, and evaluating the S-lay installation process. It uses advanced Vessel technology and real-time monitoring to provide new insights into the challenges and opportunities of laying pipelines offshore. The thesis examines the technical considerations, operational challenges, as well as the rules governing offshore sub-sea S-lay installation. It discusses important factors influencing pipeline design, fabrication & installation including water depth, seabed conditions, pipeline materials, and Pipe laying Vessel capabilities. It also explores ways to overcome geological, environmental, and logistical challenges to improve efficiency and sustainability in offshore energy projects. Additionally, the study provides different S-lay installation process, including how to handle, load & store pipeline in the offshore environment, welding and testing operations, pipelines initiation methods using anchor deployment and anchor handling tug supply vessels, install Sub-sea In-line Structures, abandonment and recovery pipelines in both shallow and deep water. It explains their respective advantages, limitations and application in different offshore environments. Furthermore, the study looks at different laying stresses in the pipeline, how to control the S-lay curve, and the dynamic behaviour of the vessel during installation. It also examines the offshore market, performance and preliminary cost needed for the operation. In conclusion, this thesis represents a landmark contribution to the state of the art in offshore pipeline installation methodologies, offering a manual for future advancements and setting new standards for excellence in the field of offshore engineering.