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** Description:** This article discusses the method of determining the frequencies and amplitudes of torsional vibrations of the shaft of a die-sel generator equipped with devices for damping torsional vibrations, clarifies the principle of operation of these devices, indi-cates the need to clarify the design scheme of the shaft lines, explains the sequence of determining frequencies and amplitudes of torsional oscillations fractions for the dynamic stiffness of the system, are given one-, two- and three-node vibration modes, it is proposed when considering a nonlinear system to go beyond the energy balance, which is given to the system by effective mo-ments, and energy that is lost in the elements of the systems, an example of the calculation of the shafting equipped to damp oscil-lations with an elastic shock absorber and elastic coupling is considered, recommendations are given on ways measuring the degree of uneven rotation of the shaft of a diesel generator. The purpose of this article is to substantiate an improved method for determining the frequencies and amplitudes of torsional vibrations, taking into account the influence on the process of the emer-gence and development of these oscillations of devices for their limitation and quenching. The results of calculations of torsional vibrations of the shaft of a diesel generator in this article are given in an illustrative example and indicate that when equipping the shafting with devices for extinguishing torsional vibrations during the operation of this shafting, there will not be dangerous torsional vibrations that can lead to destruction of the shaft. As well as the results of calculations of torsional vibrations of the shafting of a diesel generator, tell us that if you do not take into account torsional vibrations, it is impossible to accurately de-termine the angle between flashes in individual cylinders of engines, and thus it is impossible to accurately determine the degree of uneven rotational speed.

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Keywords:
** amplitude, shape and frequency of torsional vibrations, free and forced torsional vibrations in a linear and non-linear system, the influence of torsional vibrations on the determination of the degree of non-uniformity of the rotation frequency.

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