Eliminating the Influence of Support Conditions on Geometric Shape Measurements of Large Crankshafts of Marine Engines

This paper presents an analysis of the possibility of determining the geometric deviations of large crankshafts of engines using both conventional and alternative fuels. Experimental tests were carried out on a test stand adapted to measure crankshafts seated with their main journals on a set of fixed supports with the possibility of height positioning and using a reference measuring system. A comparative assessment of the results was made for a selected crankshaft using the intercorrelation factor ρ, whose value ranged from 0.8982 to 0.9751. It was concluded that the proposed procedures can be useful in assessing of the geometric condition of the crankshafts with axial position deviations and with limited possibilities of their detection resulting from the adopted support conditions with a set of supports positioned at different heights. Experimental tests were supplemented with FE-analyses of the crankshaft supported at multiple locations and loaded with deviations in the position of the main journal axes.