ASSESSMENT OF THERMAL NETWORKS’ RELIABILITY INDICATORS

Thermal networks of Volzhsky, Volgograd region, are the object of research. The aim of this paper is to determine quantitative reliability indicators expressed as failure rates, time periods between failures and establishing a failure distribution law. Research of statistical data on failures of thermal networks have been conducted in the town of Volzhsky, Volgograd region, during the operation period from 2010 through 2012 after commissioning in 1970. All revealed failures led to interruption of heat supply and, accordingly, restoration of thermal networks. The article presents mathematical relationship between an assessment of reliability indicators in the form of failure rates and time periods between failures and the pipe diameter, the extent of thermal networks and the in-service time. The novelty of this article is that research of thermal networks’ reliability has been conducted in Volzhsky for the first time, and the results of these studies show actual numerical values of failure rates and provide an assessment of time periods between failures, analyzing its relationship with the diameter of pipes, the extent of thermal networks and the time of their operation. It has been established that failure rate is subject to the exponential law of distribution depending on the diameter and extent of pipes with parameters λ = 2,77·10^-3 (1/m), T = 362 m, and the operation time – with parameters λ = 35,31·10^-3 (1/h), T = 28 h. It is recommended to use the received estimates of reliability indicators during creation of modern thermal networks. The established system of maintenance and repair ensures reliable functioning of thermal networks with a confi dence level of 99%.

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