Study On The Shafting Mis-alignment Of A Power Barge

The quality of shafting alignment will directly affect the main engine power whether effectively playing out, and will also affect the economy and reliability of the propulsion system and the safety of the ship. Therefore, high attention must be paid to the working environment and quality of the shaft in the process of operation.In this paper, a modified power barge is taken as the research object. After modification, this barge cannot be fully loaded, only completed 30% of the design load. Otherwise the shafting bearing is overload. In view of this phenomenon, this paper has carried out the following work:(1) Analysis of the problems appearing on the power barge, and to determine the root cause of the phenomenon caused by the shafting mis-alignment. Then the factors that may affect the working quality of shaft is analyzed. And combining with the response measures taken in the actual operation, the main causes of the shafting misalignment are the poor design of propulsion shafting structure or hull deformation.(2) According to the requirements of the relevant criteria, checking the shafting design itself, including the shaft diameter, shaft sleeve, stern tube and its bearings, couplings, propeller shaft and gear box load, the results show that the ship’s propulsion shafting design is reasonable.(3) Calculating and analyzing the influence of ship deformation with the finite element method. First, establishing the whole ship 3-D finite element model of the power barge. Then applying the hull load according to different loading conditions and boundary conditions in ANSYS. Then calculating the bearing load according to the deformation data of hull. The result shows that the bearing load resulting from hull deformation is too high, seriously affecting the working quality of shaft.(4)Combined with the conditions of the ship hull deformation, this paper puts forward the improvement measures for the hull transform, this measure can improve the working condition of shafting. Furthermore, carrying out the shafting dynamic alignment of the power barge considering influence of hull deformation, in order to achieve the best results.