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The study of the balance sheet structure of the regional gas supply system is necessary to solve a number of operational tasks. An information database has been created for conducting research. It includes information on daily gas consumption and the actual average daily outdoor temperature for a six-year period for more than 539 elements of the balance structure of the regional gas supply system. The most significant factors determining gas consumption were identified for 7 enlarged balance groups. It´s investigated the dynamics of factors in time. The article presents the types of daily fields “gas flow – average daily outdoor temperature” for enlarged groups of the balance structure of the regional gas supply system. Four temperature areas were identified and substantiated in the daily fields. The assessment of qualitative and quantitative indicators characterizing the temperature areas is presented in the article.

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The article describes how to use vibration diagnostics to detect defects in the installation of new equipment and to determine the quality of repairs based on vibroacoustic characteristics. Especially relevant is the vibration diagnostics of rolling bearings before installation on the mechanism. If there are errors in the calculations of the magnetic system of synchronous generators, vibration occurs, which is not eliminated during operation. Design errors, poor assembly of pumping units, asynchronous motors, power transformers cause increased vibration, which leads to damage to the specified equipment. The main reasons causing the vibration of the transformer tank are considered and the frequency range from 50 to 6000 Hz is determined on which these defects can occur. Full-scale experiments of the vibration of the transformer tank have shown that certain defects can occur in a narrow frequency band. The practical application vibration diagnostics of the pump unit describes in this article. Technical diagnosis of pumping units of the sewer station was carried out for various included composition. The results obtained made it possible to exclude reverse hydraulic impacts as a possible cause of the failure of the pump unit.

Investigation of the structure and the functional patterns of the regional gas supply systems is necessary for addressing a number of operational tasks, the main ones being the following: preparing requisitions for the planned volume of gas deliveries, project design for development and reconstruction of gas supply systems and gas storage facilities, developing of functional gas tariffs for different groups of customers. The regional gas supply system is considered from the standpoint of system analysis and presented as a complex dynamic system consisting of several subsystems. The balance structure of gas consumption in the region for the ten-year period and the patterns of daily gas consumption in the region depending on the average daily outdoor temperature for the two-year period have been studied. It is discovered that the power economy, industry and agriculture account for the largest share in the total gas consumption. The values of correlation coefficients between the outdoor air temperature and gas flow rate according to the elements of the balance structure are calculated. For the daily values of gas consumption for the needs of the population and housing-and-communal services, the highest correlation coefficient between the studied characteristics R is noted = (–0,98‒(–0,96)). Analysis of the matching fields of daily gas consumption in the region to the daily average temperature over a given one-year timeframe made it possible to identified two key areas, viz.: the area of operation of the heating system and the area of positive temperatures (the cheating system is off). For each of the areas, the dependences of the daily gas flow rate on the temperature and the effect of temperature changes on the gas consumption alteration were determined. It was found out that the temperature range from 0 to 10 °C corresponds to the zone of uncertain state of the regional gas supply system, since two areas overlap in this zone, viz.: the area of operation of the heating system and the area of positive temperatures.