The underlying concept for the Floating Spiral pipeline installation method is to wind the pipeline into a huge floating spiral, and then tow this assembly to the installation site, where the spiral is then unwound and lowered to the seabed in a single operation. In this method the pipes are fabricated on shore, which allows for optimal control of costs and quality in pipeline manufacturing. The first stage of the installation process by this method consists in setting the pipeline afloat and winding it elastically to form a large flat spiral, which is then ready to be towed to the installation site by standard tugboats. The objective of this work is to present results of studies for a long pipeline length at this first stage of the Floating Spiral method. The focus here is the process of moving the pipeline around a fixed structure to wind it and form the floating spiral. Problems related to modeling of contact between pipeline and its guides at the first spiral cycle, as well as contact between further pipeline cycles, are rigorously analyzed. Several numerical simulations are performed; the results arc presented and discussed. Other stages of this installation method have also been studied, and are presented in a companion paper.
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