Light Structures offers services in data
management onshore to help the maintenance planners and
other onshore personnel manage the assets in the best way.
Reports, which summarize the hull condition, are available
based on data from the HSM system. Data can be transferred
for onshore analysis on backup media. Regular condition
reports are a supplement to inspections and provide hull
status documentation that can be used towards maintenance
planning, customers, authorities, environmental groups and
potential buyers.
Our recommendation for analysis of actual
fatigue life in hotspots, is to place a fiber optic strain
sensor in a location near the hotspot(s) of interest, where
the stress is well defined (no gradients), and calculate the
hotspot stress and consequent fatigue damage using Stress
Concentration Factors found from the design calculations
(hotspot locations and SCFs are yard supply). One strain
sensor can be used to calculate stress and fatigue in
several nearby hotspots, based on individual SCFs for the
hotspots. Individual SN-curves may also be defined.
Comparison of actual fatigue life with
design fatigue life is a standard function in the SENSFIB
system. The result is normally presented based on the latest
half hour of data (single point in time) with a bar graph,
and the time history of the comparison implemented as an
onshore function. An online graphical representation of the
timeline can be implemented onboard as a custom function in
the Human-Machine Interface. In case there is a significant
difference between the actual fatigue life and the design
life, the system can provide the user with advice on the
cause of this difference. The standard function is to
present the overall fatigue life calculation together with
the contribution due to wave loading (included in design
life) and contributions due to vibrations (not included in
design life). With access to a full set of design parameters
and environmental data, including wave data, it is possible
to extend the advisory function to include a comparison of
the actual loading conditions with the loading conditions
used for design life calculations, as well as a comparison
of the actual wave scatter with the design wave scatter.