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The safety of basic parts of the rolling equipment is most at risk due to the complex geometrical shape and significant levels of nominal stresses. With a significant mass of such parts and a long production time, the replacement process is accompanied by the need to dismantle the old mill and install a new one. Currently, there are no specialized methods for assessing the risks of failures in relation to the rolling equipment, therefore, it is required to develop new methodological provisions and adapt the existing general methods of risk assessment to real production conditions. Based on the fundamentals of the regulatory document, a methodology for assessing the risks of failures in relation to the rolling equipment has been developed. The roughing stand of the “2000” hot rolling mill for titanium alloy sheet production was chosen as a practical object for assessing the risks of failure. The preliminary analysis of the dangers and their consequences had shown that for most of the elements of the working stand, which perceive the rolling force, as well as for the units and parts of the main drive loaded with the rolling torque, there are dangers that can lead to disruption of the deadlines for fulfilling orders for rolled products. For a numerical assessment of these risks, special calculations were performed.

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The article addresses to distribution of loading between working and backup rolls of sheet levelling machines taking into account presence of initial gaps between them and heating that occurs during the straightening process, which is especially important in case of the high-temperature straightening. For levelling machines with a single row of backup rolls calculated dependencies were obtained to evaluate loads suffered by backup roll taking into account factors under this study and the analysis of results for the 9-roll straightening machine were carried out. The analysis showed a significant overload suffered by backup rolls.

For the leveling machines in conditions of a small batch production which is typical for manufacturing sheets of non-ferrous alloys, in particular, titanium, the rollers heating is very influential. In order to expand the technological possibilities of the main equipment in non-stationary thermal working conditions of rollers that is an actual new scientific problem the experimental study of the loading in the hot leveling of slabs made from hardly-deformed titanium alloys was carried out on the 9-roll leveling machine. To achieve this goal the methodology of the complex experimental study of the actual loading definition of the leveling machine drive was developed. The experimental study was carried out for alloys Ti6Al4V (Vt-6s) and PT-3V with the initial heating temperature of the rolled product from 750 to 850°C. The slab leveling process was logged for slabs with the thickness from 20 to 68 mm, the width from 985 to 1720 mm by the number of passes through the leveling machine from 2 to 8. The treatment and analysis of experimental data was conducted on the basis of which the summary of permissibility of assortment expansion of leveling slabs has been formulated.