CRANE TYPE
STS Crane
ASSESSMENT
Residual Life Assessment
PROJECT OVERVIEW
The Challenges
The main goal of the study was to determine the residual fatigue life of two Ship-to-Shore (STS) cranes.
The cranes were not equipped with lifting load loggers that could provide precise historical data for the residual life assessment. Therefore, crane operating cycles and lifting load history provided by the crane owner were used as the basis for the assessment
FATIGUE ANALYSIS
Identification of Critical Structural Areas
FE-based fatigue analysis was performed to identify the critical areas of the crane structures. The gantry and trolley structures were considered separately.
Gantry
Trolley
MATERIAL ASSESSMENT
Assessment of Accumulated Fatigue Damage
The fatigue damage accumulated by the time of the assessment was evaluated based on measured changes in material hardness within the critical structural areas identified by the FE analysis
RESIDUAL LIFE CALCULATION
Residual Fatigue Life Assessment
Considering the accumulated fatigue damage for each critical area together with the typical crane operating cycle, the residual fatigue life of the crane structures was calculated
PROJECT OUTCOME
Engineering Assessment Result
The assessment provided an evaluation of the accumulated fatigue damage and residual fatigue life of the two STS cranes based on FE analysis, material hardness measurements and the available historical operating data