Technical focus of the research is a discrete throttle valve (DTV) and gas pipeline. An extensive research of vibration and acoustic characteristics of the main pipeline of a gas distribution station was carried out. The acoustic noise power level radiated by the main gas pipeline and it's comparison with the strength criterion were made. The levels of vibration acceleration in different parts of the main gas pipeline were measured. On the basis of experimental data the possible causes of the acousticinduced vibration are described, and measures for reducing vibration loading of a gas pipeline were proposed.

Pressure-reducing devices such as protective valves, control valves and chokes can create high levels of high-frequency acoustic waves at the outlet of the valve. These acoustic waves are propagated along the pipe, thereby generating vibrations, which in turn lead to fatigue failures, sometimes malfunctions set in within a few hours. In this research work, we have studied the main approaches of the vibroacoustic characteristics analysis that as a result has allowed us to develop the method of calculation of vibroacoustic characteristics, which would help to make the assessment of pipeline strength, of pipes noise and vibration levels more practicable. At this method different ways could be employed to get the desired results depending on the kind of data (measured vibroacoustic characteristics, geometric characteristics of the element, the input parameters).

The background for the proposed methodology is based on the principle of stage throttling with simultaneous equalizing and stabilizing the outflow, as well as elimination of gas-dynamic self-oscillating modes of the control valve. Having conducted an analysis of suppression and dampening means and according to established patterns of occurrence of self-oscillations we have suggested an integrated pulsations damper performing the following functions: elimination of gas-dynamic self-oscillations, reducing pressure pulsations in the source by reducing pressure drop, stage throttling with a reduced flow rate and outflow stabilization. A distinctive feature of our methodology is combining experimental dependencies with numerical simulation of natural modes and gas-dynamic processes taking place in the control valve and pressure pulsation damper. As initial data for designing the damper we have set its desired efficiency while ensuring specified operating modes of the gas distribution station and specified restrictions on dimensions and hydraulic resistance. The methodology allows for a significant reduction of broadband pressure pulsations and vibration by the damper due to the rational and maximum permissible distribution of pressure differences in the control valve and damper under operating conditions in which the total vibrational power of the control valve and damper is maintained close to the minimum.

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