Increased power demand over the world have been driving many developing countries with planning the construction of the power plant. The lack of water in the world are requiring facilities which could convert seawater into drinking water. The key facilities used for these power plant and desalination systems are intake and outfall pipelines, which provide crucial functions of supplying and discharging seawater. And the diameter of the pipe should be enlarged to supply affordable amounts of seawater into these facilities,
Recently, for water intake pipeline systems High Density Polyethylene Pipe (HDPE) have been preferred candidate material compared to other possible materials such as steel and Glass Fiber reinforced epoxy based on the development of HDPE manufacturing technologies and its numerous advantages. Daewoo Engineering & Construction (Daewoo E&C) have been performing construction of Ras Djinet Combined Cycle Power Plant (RDPP) Project and HDPE pipeline was adopted for providing seawater into the onshore cooling water system.
HDPE pipes have many beneficial features, such as light weight, flexibility and ductility, and well-suited for marine applications. But design and installation of the HDPE should be done carefully so that excessive bending stress and sudden sink may not be happened. The float-and-sink installation method was adopted to laying the pipeline with 2500mm diameter into the seabed in the project. The ballast weight are clamped along with the pipeline as designed space. The aims of the paper are to present the design procedure of the large HDPE pipeline and show the float-and-sink installation.