The analysis of forced oscillations and waveformations of heavy ropes of hoisting mechanisms of cranes in the processes of starting the latter is carried out. The main parameters of the resulting waveforms in the ropes for different ways of lifting the load ("with a pickup", "by weight") are determined. The influence of gravity on the rope and the longitudinal oscillations arising in it, as well as on the longitudinal waveforms arising inside it are investigated. The rope of the lifting mechanism, in this case, is considered as a tensile rod. The laws of motion of cross-sections of ropes are established, according to which the forces arising in ropes are minimized during the startup of hoisting mechanisms of cranes. The application of the integrodifferential equation, which adequately describes the oscillations of the rope system of cargo cranes, and also takes into account the frequencyindependent internal friction in these systems, which accompanies the oscillatory processes in the ropes during transient reagents for their differentiation by different ways of lifting loads. The parameters of the established harmonic oscillations of the rope system of cranes for long-term lifting of the load and taking into account the inertial properties of the rope (considerable length), as well as the magnitude of the static movement of the rope (for different ways of lifting loads) are determined.
Nonlinear forced oscillations of an unsymmetrical shaft and an unsymmetrical rotor with quartic nonliearity. 2nd report. Variations of resonance curves of summed-and-differential harmonic and super-summed-and-differential harmonic oscillations and the occurrence of unstable vibrations.
