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A one-dimensional model for the analysis of compression of a paper in the printing machine is presented. It is assumed that a paper experiences static compression and the problem of initial stability is solved. A two-dimensional model for the analysis of compression of a paper is described and used for the solution of a similar problem. Also an axi-symmetric model for the analysis of compression of a paper is described and used for the solution of a similar problem. A setup for performing experimental investigations of uniaxial unidirectional symmetrically distributed compression of polymeric film is designed and created. For this purpose the method of digital speckle photography is used. During the investigations the images of the stability eigenmodes of the polymeric film HDPE for uniaxial unidirectional compression of the film were determined. The obtained results are used in the design of the elements of the printing machine. [ABSTRACT FROM AUTHOR]

The stress strain law on the basis of the model of a visco-elastic body is proposed. Procedure for numerical integration of equations of motion is developed. Results of numerical calculations of vibrations of a visco-elastic structure are presented. It is assumed that a paper in a printing device is loaded in its plane and thus a problem of plane stress is analyzed. The principal stresses are calculated and represented at the centers of finite elements. They substantially determine the vibration behavior and stability of the polymeric film. The first eigenmodes are presented for a paper performing transverse vibrations as a plate having additional stiffness due to static tension in its plane. Stresses in the polymeric film in the transverse and longitudinal direction of transportation of the tape were determined by using experimental methods for the symmetric and non-symmetric loads. For the investigation of the eigenmodes a special experimental setup was used in which the eigenmodes of the paper tape were determined by using the method of projection moire under the action of vibrations to the tape of paper for the symmetric load. Comparison of the experimental and numerical results of investigation was performed. [ABSTRACT FROM AUTHOR]

It is assumed that a sheet of paper performs transverse vibrations as a plate having additional stiffness due to static tension in its plane. The first eigenmodes are determined. The setup for experimental investigation of the nodal lines of the standing waves and for the determination of eigenmodes using projection moire is created for the analysis of unsymmetric loading of the paper. The comparison of the theoretical and experimental results of investigations is performed. The obtained results could be used in the process of design of the elements of the printing device. [ABSTRACT FROM AUTHOR]

The model for the analysis of vibrations of paper in a printing device is presented. It is assumed that paper performs transverse vibrations as a membrane having stiffness due to static tension in its plane. The first eigenmodes are determined. It is shown that the eigenfrequencies of transverse vibrations of the analyzed paper can be controlled by the static tension in the plane of the paper. The model for the analysis of stability of paper in a printing device is presented. It is assumed that paper moves with constant velocity in a given direction. The analysis is performed using a plate-bending element with the contribution of the forces of inertia from the convective accelerations. This results in the eigenproblem determining the critical velocities and stability eigenmodes. The stand was made for obtaining the experimental investigations. Using it the nodal lines of the standing waves were determined and using projection moiré the eigenmodes were determined. The obtained results are used in the process of design of the elements of the printing device. [ABSTRACT FROM AUTHOR]