Effect of production factors on change of surface roughness parameter of trained cold rolled strip

The purpose of the study is to develop a method for determining of the range of fluctuation of the surface microgeometry parameters of a cold-rolled strip when training it in rough rolls, taking into account the disturbing effect of the elements of the equipment of the training mill. Mathematical dependences are obtained that allow us to estimate the change in the rough layer of the surface of the trained cold-rolled strip according to the parameter the arithmetic average roughness height, depending on the thickness and permissible deviations from its nominal parameter, the initial roughness of the roll surface, training modes, tension fluctuation, runout of the support roll, the relative amount of material in the rough layer of the roll and strip, the step parameter of the roughness of the working roll, the length the projected strip. The effect of disturbing actions on the fluctuation of the reproduction coefficient on the example of training the most popular cold-rolled products with a width of 1500...2000 mm and a thickness of 0.65...0.9 mm is considered. It is found that in production conditions for the broadband training mill 1700 the formation of the roughness of the strip and the change in its arithmetic average roughness height is characterized by unstable values. The results can be used in analyzing the causes of increased fluctuations in roughness parameters along the strip length and between rolls, as well as in developing organizational measures aimed at reducing fluctuations in the arithmetic average roughness height and obtaining a more isotropic microgeometry of a trained cold-rolled strip.