The paper presents the results of experimental studies to determine the strain properties and characteristics of a chrome leather semi-finished product of middle-weight bovine hide by its topographic sections and the coatings of the processing compression rolls. The strain pressure equations of depend on the topographic sections of a leather semi-finished product are obtained, and the results of experiments on the effect of a number of layers on the amount of pressed moisture are presented. A mathematical dependence of the pressed moisture from the leather semi-finished product is obtained under various pressure values, rates, and the number of skin layers with monchons. The influence of the number of layers of leather semi-finished products with moisture-removing materials (monchons) on the process of moisture extraction at their vertical feed on the base plate is determined. In this paper, the influence of the number of skin layers and moisture-removing materials (monchons) on the technological process of moisture extraction from wet leather semi-finished products at their vertical feed on a base plate is studied as well.

The leather industry includes many technological machines; a squeezing roller machine is used in many operations, for example, in squeezing, degreasing, and after drum dyeing of a semi-finished leather product. The paper presents the results of experimental studies obtained by determining the influence of multilayer wet leather semi-finished products with monshons under squeezing on the amount of the moisture extracted. Mathematical dependences of the amount of the moisture extracted, for each layer of a five-layer wet leather semi-finished product on the feed rate between the squeeze rollers and the roller pressure were obtained. Experimental research is of scientific and practical importance for the development of a technological process for extracting moisture from wet leather semi-finished products used in the tannery, since the quality of the extraction affects the quality of subsequent technological operations, such as leather shaping and splitting. An experimental study was performed using the method of mathematical statistics, namely, the method of mathematical planning of the experiment. Mathematical models were obtained for the amount of extracted moisture from five wet leather semi-finished products depending on the rate of their simultaneous feed and the pressure of the squeezing rollers. The results of the experiment showed that in squeezing a five-layer product, the productivity of the technological process of extracting moisture from wet leather semi-finished products increases by five times in comparison with existing squeezing roller machines. The use of the results of the experimental study will contribute to a significant reduction in the energy consumption of the squeezing roller machine by simultaneous multi-layer processing of wet leather semi-finished products

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The article presents the results of experimental studies to substantiate the performance of the method of simultaneous extracting excess moisture from wet leather semi-finished products. In the experiment, the influence of the feeding speed, the pressing force of the squeezing rollers on the amount of moisture removed from two layers of the leather semi-finished product after their squeezing was determined. The experiment was conducted using a moisture-removing material - a BM brand monchon, laid on a guide bar, on which two layers of the wet leather semi-finished product were previously folded. A monchon of the LASCH brand is folded between the layers of a semi-finished leather product. Due to the flexibility of the monchon, the displacement of semi-finished leather products movement path along the conveying device is reduced.

The parameters of the improved design of the pressure mechanism of a roller technological machine for squeezing wet materials are investigated in this article. The factors influencing the parameters of the pressure mechanism, which provide the required force between the working rolls of a technological machine during the processing of moisture-saturated fibrous materials, such as wet leather, were studied. The processed material is drawn in the vertical direction between the working rolls under their pressure. This study aimed to determine the parameters that make it possible to create the required pressure of the working rolls depending on the change in the thickness of the material being processed. A pressure mechanism of working rolls mounted on levers is proposed. In the design of the proposed device, the length of the levers does not change due to the movement of the sliders when turning the levers; this provides a horizontal direction of the sliders. The change in the pressure force of the working rolls is determined depending on the variation in the nip angle, the coefficient of friction, and other factors. Based on theoretical studies concerning the feed of the semi-finished leather product between the squeezing rolls, graphs were plotted, and conclusions were drawn. An experimental roller stand designated for pressing multi-layer leather semi-finished products has been developed and manufactured. An experiment was carried out to determine the factors affecting the technological process of squeezing excess moisture from wet semi-finished leather products with their multilayer package together with moisture-removing materials by means of their vertical supply on a base plate between rotating squeezing shafts also covered with moisture-removing materials. According to the results of the experiment, the optimal process parameters were selected. It is recommended to carry out the process of squeezing the moisture from two wet semi-finished leather products at a pass rate more than twice as high and with a pressing force of the working shafts two times lower compared to the analog. According to the results of the study, the optimal parameters for the process of squeezing the moisture from two layers of wet leather semi-finished products were chosen, namely the feed rate of 0.34 m/s and a pressing force of the squeezing rollers of 32 kN/m. The use of the proposed roller device allowed an increase of two times or more in the productivity of the process of processing wet leather semi-finished products on the basis of the proposed technique compared to known roller wringers.