Construction of cylinders in offset printing presses and its vibratory consequences

Vibrations in offset printing presses are serious problem, which beside influence on machines’ parts, are also source of problems with printing process and achieving prints of right quality. In this paper construction of offset printing unit is presented. Reasons of vibrations and their types in printing units are shortly described. Moreover, this article shows the role, which some of printing unit’s elements play in resisting of vibrations appearance. There is model of printing unit of sheet-fed offset printing machine presented in here. Model is described by the system of differential parametric equations. There were computer simulations realized, that pointed conditions, which should be fulfilled, so the parametric vibrations occurred.