SOME STRUCTURAL ASPECTS OF LPG CARGO TANK DESIGN AND CONSTRUCTION

摘要

The work describes the structural design procedure of cylindrical and bilobe cargo tanks, Type C as pressure vessels, according to the classification rules and supported by FEM analyses. This is illustrated for the case of 3480, 6500 and 8350 cbm LPG carriers. Some structural aspects as stress concentration in dome located in the area of stiffening ring, and two types of swash bulkheads, i.e. perforated hemisphere and flat grillage, are analysed. Misalignment problems, arising during tank construction, are pointed out: Y-joint of bilobe tanks in cylindrical area and area of torispherical and hemispherical heads are presented and valuable remedy solutions offered. Also, the sloshing phenomenon in a long deck tank has been included.