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Considering again the Steep Wave Riser example – if this were to be modelled using lines, you would probably create a single line with three subsections. In fact, this is another advantage of using lines over cables. As described in Using Multiple Cables earlier, it is not advisable to group sections of very different properties together in to a single cable, as the average properties used by the cable pre-static step may lead to an inaccurate initial estimate of the actual configuration. So the steep wave riser requires three separate cables, whereas a single line definition is sufficient. Furthermore, the use of lines means that you do not have to manually estimate initial coordinates for the cable intersection points (i.e. the ends of the buoyant section).
The line might be called “Riser”, with subsections entitled “Lower Catenary”, “Buoyant Section” and “Upper Catenary”, respectively. It is important to define meaningful names, as these names will be used by the program to automatically create relevant element sets for you, which you can subsequently reference when you are assigning structural and hydrodynamic properties to your model. This aspect is discussed in more detail later in Structural and Hydrodynamic Properties.