Determination of rational parameters of a device for leather feeding to the machining area

Abstract

The quality of mechanical processing of the skin largely depends on the parameters of the skin feeding to the processing zone between the working rolls. The processed material at the entrance to the processing zone must be free of folds and wrinkles, i.e. one layer of material should enter the processing zone of the working rolls. Therefore, the input of the processed material into the zone of the working rolls is ensured with a rational selection of the profile of the guiding device for feeding the skin into the processing zone. A mathematical model was developed that allows the authors to determine the profile of the guiding device for leather feeding into the processing area between the working rollers, considering the modulus of elasticity and the density of the material being processed. The graphical solution to the mathematical model of the guiding device profile was made by a numerical method, and in order to prevent the leather saturated with liquid from sticking to the guiding surface, the friction coefficient was replaced with the rolling friction coefficient, and the rollers of the guiding device were placed at a certain angle to level out the folds of the leather and smoothly feed it to the processing area. A new design of roller technological machines was manufactured in laboratory settings. The roller machine is equipped with a new guiding device using rollers, with the possibility of free rotation around its axis. The rollers can be placed in several rows in a staggered arrangement. The developed design of the guiding device, due to the installation of the rollers at a certain angle relative to the direction of skin feed, makes it possible to smoothly transport the treated skin while eliminating longitudinal and transverse folds. The elimination of wrinkles contributed to an increase in the usable area of the treated leather samples. Experimental and testing work was conducted on a roller squeezing machine for processing leather samples using a new design of guiding device. The working width of the guiding device was 1500 mm, and the rollers of a diameter of 30 mm, allowed the straightening of the folds of the leather and moving it to the gripping zone of the working rollers. In the experimental study, the second-order D-optimal planning method was used with the Kano design matrix.

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

“…1) consists of 4 kW DC electric motor supports 9, 11 of the lower and upper rolls are installed. Squeezing rolls 12, 13 are mounted on supports 9, 11 using rolling bearings [12][13][14].…”

“…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].…”

Study of the movement of semi-finished products between working shafts

“…Substituting the expression ( 12) into (11), we get the expression for finding the generalized force. (13) For a mechanical system with an ideal, holonomic and non-releasing coupling, we write 2-type equation:…”

“…The feeding is conducted by a belt conveyor; a significant drawback in the designs of squeezing machines is the draining of the squeezed fluid to the workplace of attendants. In this regard, the authors of [6][7][8][9][10][11][12][13][14][15] proposed devices and performed studies, the results of which make it possible to eliminate these drawbacks.…”

Device for Determining Permeability of Tanning Liquid

“…One of the factors determining the efficiency of fluid squeezing from wet skin products and increasing the intensity of squeezing is the coefficient of filtration in the skin sections and in LASCH and BM cloths (moisturewicking materials). To meet the requirements for high quality processing of skin materials, it is necessary to determine the filtration capacity of the skin product in its topographic sections and of the LASCH and BM cloths [3][4][5]. The cloth of the LASCH and BM brands is used in the tannery for covering the squeezing rollers in the form of stockings and a conveyor belt.…”