Trends of large-scale ships have seen propulsion shaft and propeller sizes increase. This has enabled shafts to have greater stiffness, yet has caused flexibility to lessen and induce bearing failure at the aft stern tube bearing. In general, shaft alignment is calculated and evaluated in accordance with classification societies’ rule requirements. Especially, positioning reaction support and stiffness of aft stern tube bearing are based on the practical experience of shaft alignment. Therefore, in this study, to evaluate the feasibility of the reaction force supporting position and stiffness of the aft stern tube bearing as recommended by classification societies in shaft alignment, theoretical reaction force supporting positions for various ship propulsion shafting systems were examined and the differences were evaluated. The reaction force supporting position of the aft stern tube bearing provided by classification societies was evaluated and it was found that a propeller shaft diameter less than 600 mm is within the provided range. However, in the evaluated shafting system, a propeller shaft diameter of more than 600 mm tends to cause the ship to move to the forward side due to increased shaft stiffness.

大型船舶的趋势已经看到，推进轴和螺旋桨的尺寸在增加。这使轴具有更大的刚度，但在后尾管轴承处产生了减小和引起轴承故障的灵活性。通常，轴对齐是根据船级社的规则要求计算和评估的。特别是，尾轴管轴承的定位反作用力支撑和刚度是基于轴对中的实际经验。因此，在这项研究中，为了评估船级社在轴对准中建议的后尾管轴承反作用力支撑位置和刚度的可行性，研究了各种船舶推进轴系的理论反作用力支撑位置，并进行了差异分析。评估。评估了船级社提供的后尾管轴承的反作用力支撑位置，发现螺旋桨轴直径小于600 mm在规定范围内。但是，在评估的轴系中，由于轴刚度增加，螺旋桨轴直径大于600 mm往往会导致船舶向前侧移动。