Controllability and stability capacity of a roll pair motion research

Abstract

The process of deriving the equation of the perturbed motion of a roll pair during the processing of leather material is discussed in the article, taking into account the influence of dynamic factors. It is shown that one of the reasons for the unstable stress state on the contact surfaces in the roller mechanism are dynamic factors arising from inaccuracies in the manufacture of its individual parts, assembly defects, and the occurrence of an oscillatory process in the roller mechanism, as well as due to the non-uniform thickness of the processed material at its gripping during starting and stopping the machine. Methods for determining optimal controls are shown; they provide asymptotic stability of the unperturbed motion of a roll pair and the torque applied to the upper roll as a function of generalized coordinates.It is shown that the width of the contact strip of the clamp, which depends on the radii of the rolls and the hardness of the coatings, has a significant effect on the efficiency of the rolls. The larger the shaft radius, the lower the actual pressure per unit contact area.
 It is shown that the squeezing efficiency increases with the improvement of the conditions for the removal of the squeezable liquid from the rolls (with their horizontal arrangement), with an increase in its temperature and a decrease in viscosity. Efficiency decreases with increasing material speed and thickness.
 It is shown that the width of the contact strip of the clamp, which depends on the radii of the shafts and the stiffness of the coatings, has a significant impact on the efficiency of the shafts. The larger the shaft radius, the lower the actual pressure per unit contact area

Experımental determination of the breakaway force of working rolls when processing semi-finished products

“…2). The average thickness of the semi-finished product was 0.005 m [9][10][11][26][27][28][29]. From these 10 semi-finished leather products, 0.10 × 0.35 m strips were cut out with a cutter across the ridge line and numbered, and the strips were arranged into groups of 10 pcs.…”

“…When creating technological machines for manufacturing industries, in particular, in tanneries, during the operations of squeezing fluid out of semi-finished leather products on a roller-squeezing machine, it is necessary to determine the required breakaway force for the pairs of working rolls [6][7][8][9][10][11][12][13][14][15].…”

Conditions for vertical pulling of semi-finished leather products under driving rollers

“…Publications of foreign scientists are devoted to modern methods of research and analysis of the properties of leathers and hides [16][17][18]. The issues of improving the design of roller equipment, including the study of the interaction of the roll module with the processed material, are described in [19][20][21][22].…”