On the question of increase of the ?quality? of sheet rolling mills

The following main objectives were put and realize in the article: to confirm the peculiarities of the process of loads generating inside the machine’s elastic system with regard to both the level of external action and own elastic characteristics of the machine; determine the load’s spectrum for iron and steel machines of sheet rolling mills, including useful and harmful loads, acting jointly and determining its strength and durability and also to work out the methods of reducing and limiting the loads, generated in iron and steel machines. In his previous publications the author mentioned many times that iron and steel machines possessed low ?quality? (i.e. technological load in relation to general load), so for these machines the share of useful loads could evaluate but a small portion of the general load. For the field lines of these machines the ?quality? can vary within 0 ? K ? 1.0. At K = 0 the entire load remains parasitic. At K = 1.0 the entire load is useful (technological). For rolling mills their ?quality? for the entire operating time in the bulk of field lines is quite high and stable. The exception is the time of transition process (metal gripping with rolls, acceleration, slowing down etc.). For sheet and plates rolling mills the ?quality? value at gripping is 0.2 ? K ? 0.5, the time of gripping being tenth fractions of a second. The ?quality? can be raised by changing working characteristics of the corresponding field lines. The most promising variant of alternating the working characteristics is developing and implementing of special active appliances. The essence of the method of reduction of the rate at metal gripping, proposed by the author is in mounting of an elastic energy accumulator in the drive of the roughing stand of 1,700 wide-strip rolling mill of ?Ilyich iron and steel works? PSC, which can be rotated by 120…180° at nominal loads of the drive. It allows to reduce by two times the gripping rate 9and accelerate), the number of mill’s engine revolutions, remaining the same. In this case the energy accumulating shaft, equipped with an elastic element, made of up-to-date polyurethane elastomers is an active part. i.e. the part, that has a sufficient influence upon the value of generated loads. In the given example the quality was raised from 0.25 to 0.4