연속식 하역기 L-홀더의 잔존 수명 예측 = Prediction of the Remaining Useful Life of L-holder for Continuous Ship Unloader

다국어 초록 (Multilingual Abstract)

A Continuous Ship Unloader (CSU) is a facility in which multiple buckets rotate to excavate cargo from a ship to land. It is typically designed to have a lifespan of 20 years. However, fatigue damage is likely to occur before the end of itsdesignated lifespan. This study aims to examine the possibility of extending the component's lifespan by evaluating the remaining useful life of L-holder, a part of CSU, that has been in use for 20 years. Fatigue load history was predicted by measuring the strain with or without strain at the L-holder part requiring periodic replacement. Through tensile and fatigue tests, the remaining life was evaluated when cracks were not present. In addition, the remaining life in the presence of cracks was evaluated through destructive toughness test and fatigue crack propagation test. Life prediction results based on test cycles were obtained. The proposed guidelines are expected to be helpful for preventing CSU accidents.