The Shaft Design Scheme And Alignment Of Some 110000 Tons Oil Tanker

Shaft is the important component of the ship. The quality of shaft alignment is very vital during the building of the ship. The alignment quality is related to the normal running of ships for a period, safe navigation and lives' safety. Specially in modern time, with the appearing of building large ships(VLCC, ULCC), the study and application for shaft alignment is becoming one of the best important tasks which need to be solved.The shaft of 7RTflex58tb is studied in some 110000tons oil tanker. First, we optimize the shaft, it means to confirm the best reasonable place of intermediate bearing to align. Second, the alignment is done with moving the intermediate bearing 1.6m afterward and removing the stern forward bearing, finally, the alignment is to be done with removing the intermediate bearing. We compare the three different kinds of alignment plans for the shaft, analyze the data and appraise the three kinds of shaft alignment plans.This article expatiates the applicable method for the shaft alignment calculation and rationale in element process, setup of model and alignment calculation. Transfer matrix theory is selected as the calculation way for the alignment. This article still expatiates the shaft optimization theory, and uses hydraulic jack to measure the load of intermediate bearing. Besides, an improved way to measure intermediate bearing load is introduced.The result shows that intermediate bearing has a complicated effect on shaft alignment. First, the plan of optimizing intermediate bearing's place can be not suitable for large vessels. Second, the two plans of removing intermediate bearing and stern forward bearing are available for alignment. Removing intermediate bearing and stern forward bearing supply a simple and effective way for large ships that hull deformation have an important effect on shaft alignment.