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

The structure of finished leather and semi-finished products differ in physical and mechanical parameters. To obtain the properties of elasticity, pliability, and viscosity required in leather production, it is necessary to ensure their values that guarantee the high quality of the resulting product. In this article, a model for finished leather is obtained based on combining the viscoelastic Kelvin model with the deformationinert Khusanov model and the Bingham–Shvedov viscoplastic model. This model makes it possible to improve the elastic-viscous plastic deformation of a fibrous material (leather). The possibility of clarifying the pattern of change in the deformation curve depending on the time the fibrous material is loaded by a certain force was explored. The aim of refining the deformation curve is that in known models, at the initial moment of loading, deformation occurs instantly up to a certain value, which does not fully describe the real physical process of deformation of the material. Consequently, in the proposed refined model, the deformation is fixedat zero value, which provides a real physical pattern of deformation of the fibrous material. The refined model will serve designers of technological machines to develop parameters of deformation during the mechanical processing of elastic-viscous plastic materials.

RETRACTED: Refined model of leather

Bahadirov,

Nabiev,

Tsoy

2024

Improvement of quality indices of leather fabrics of fur skins

Bahadirov,

Nabiev,

Tsoy

2024

The article is devoted to research on improving the quality indices and elastic-plastic properties of leather fabric of fur skins. An improved method and operative parts were developed that help ensure high elastic-plastic properties of leather fabrics of fur skins after mechanical processing. The design and geometric parameters of the operative parts of the improved design were studied and analyzed. It was determined that when using the recommended operative parts, the required quality of leather fabrics of fur skins is achieved by increasing the contact points between the operative parts and the processed material.

RETRACTED: Experiments on pressing elastic-viscous products

Bahadirov,

Nabiev,

Tsoy

2024

The effect of various factors on the amount of fluid removed in the technological process of squeezing multilayered raw hides by pressing between plates is experimentally studied in the article. The influence of various factors on the pressing process was determined (for example, the installation of moisture-wicking cloth between the layers of raw hides) and their patterns were established. Results were obtained to determine the effect of moisture-wicking cloth on the efficiency of the process of excess fluid extraction from wet raw hides with the pressure on leather products clamped between the lower and upper plates from 11 to 18 kN/cm2. The installation of fibrous cloth of the BM brand increases the uniformity of fluid removal over the topographic sections of the raw hide, which reduces the storing time after squeezing moisture. The installation of a porous fibrous cloth of BM type between the layers of raw hides eliminates the difficulty of separating the layers of the raw hide. A new method for squeezing out excess fluid from wet raw hides using moisture-wicking cloth by pressing is proposed instead of using metal gratings.