Reliability analysis in subsystem of heat supply

Subsystem of heat supply is one of three subsystems constituting heat supply system together with subsystem of heat production and subsystem of heat distribution. An analysis of failures in the heat supply subsystem has been presented in the article. The analysis of variety, frequency and causes of failures, for individual kinds of district heating network: main ones, distributional ones and heat supply connections in the example of heat supply system of 200000-inhabitants-city has been presented in the work. An analysis has been based on a real exploitation data of the heat distribution network, which had been obtained from Municipal Heat Supply Company during the period of time from 2003 to 2012. This paper contains the failure analysis of the heat distribution network depending on the technology of construction, diameters and age of network, kinds and causes of damages, place and time of failures' occurrences for various kinds of heat distribution networks. There have been determined basic reliability parameters such as: mean time between failures and the failure rate in the exemplary subsystem of heat supply. The failure analysis of heat distribution networks allows the operating instructions to develop, which can serve as a basis to determine the optimal repair periods and periods of highest danger emergency. It also influences on making more accurate decisions considering maintenance and repairs. This reduces the consequences of the failure, which is related to the maximum shortening of repair time and to decreasing the negative results of interruptions in the heat supply to the customers.