Leading Classification Society ClassNK has released its Guidelines for Liquefied Gas Carrier Structures – Independent Prismatic Tanks (Second Edition). The Guidelines specify the technical requirements specifically related to the structural strength assessments of liquefied gas carriers by using direct calculation.
The two components of the Guidelines include the Guidelines for Direct Strength Analysis, and the Guidelines for Fatigue Strength Assessment. The newly released Second Edition contains the portion about the Guidelines for Fatigue Strength Assessment.
Based on the latest knowledge acquired through Class NK’s R&D, the Guidelines for Fatigue Strength Assessment outline strength assessment methods against fatigue cracks caused to vessels by prolonged and repeated loads. By implementing fatigue strength assessment methods that follow the guidelines, it becomes possible to carry out more reasonable fatigue designs for primary members of not only hull structures, but also of independent cargo tank structures and their support structures.