Historically, 6D buoys have often found uses other than their obvious intended purpose. For example, they have been used to connect two line ends together in a way that accounts for the moment transfer between the lines without either of the lines needing to include torsion. Sometimes they were used simply to provide a convenient frame of reference, where the physical properties are provided by various other model objects (usually single segment lines) connected to the buoy.
| Note: |
Such tasks are usually more appropriately performed by constraint objects, which were developed specifically for these sort of applications (amongst others), and which have largely superseded 6D buoys for these tasks. You may, however, come across OrcaFlex models which still use buoys in this way. |
For these sort of uses, the 6D buoy commonly needs negligible structural and hydrodynamic properties; hence the give buoy negligible properties button on the 6D buoy data form, which
- sets the buoy type to lumped buoy
- does not change height, since it cannot be zero (its value is not significant anyway, since the other properties are negligible)
- sets all other lumped buoy properties to zero
- does not modify any existing wing, applied load or drawing data
