Kazan National Research Technological University (Kazan, Russia):
Nguen Wang An, Graduate student, Dept. of Machines and Apparatus of Chemical Production
L. N. Moskalev, Cand. Eng., Head of Laboratory, Dept. of Machines and Apparatus of Chemical Production, e-mail: lejnya@yandex.ru
S. I. Ponikarov, Dr. Eng., Prof., Head of Dept. of Machines and Apparatus of Chemical Production

The influence of non-stationary heating and constant power loads on the strength of the fitting-shell connection made of cold-resistant 09G2S steel grade is considered. From such steel various chemical, petrochemical, oil, gas, power equipment is made. According to existing methods, the calculation of welded joints for strength is carried out only on one of two conditions: either overpressure or constant temperature. Therefore, the task of calculating the strength of nodes of intersections of thin-walled shells, namely the connection of the fitting with the shell while loading the node with a constant force load with non-stationary heating can be considered relevant. Solutions to these problems in the analysis of technical literature are not identified. Such loadings are possible in such situations as accidents, incidents, sharp input in the device of hot environment, fire in the zone of fitting – shell connection, etc. Numerical experiments of the stress-strain state of the node connection of fittings have shown that the maximum equivalent stresses increase rapidly and then decrease with a return to stationarity. It is known that equipment of chemical and petrochemical industries is often used in conditions of high temperatures and pressures required for technological processes. Factors such as personnel safety and equipment life expectancy affect the efficiency and economy of any business.

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