Influence of Local Resistance on Pressure and Speed Changes in Expanded Pneumatic Conveying

In this article, the qualitative indicators of yarn obtained from cotton fiber stored in a bundle of small sizes and volume were considered in order to determine its quality by processing the results of a full factorial experiment. Attention was also paid to the time spent on the experiment and the equipment used. Based on this and assuming the presence of a paired influence between the factors, the central compositional rototable planning of the experiment of the second order was adopted. The experimental study was planned to be carried out in two stages. A full-factorial experimental study was carried out on a small-sized spinning machine “Shirley” JSC “Scientific Center Pakhtasanoat” and yarn T-19.5 tex was produced. To determine the physical and mechanical properties of the threads, modern equipment of the testing laboratory “CentexUz” at TITLI was used. The results of a full-factorial experiment on the production of yarn from cotton fibers in a bundle of small sizes or volume are shown in tables 1-5, based on the results of the experiment, regression coefficients were found and equations were drawn up. According to the results, the threads of the 6th variant in terms of indicators were recognized as the best option.

Section: Methodsmentioning

confidence: 99%

Mathematical processing of the influence of cotton storage conditions on yarn quality indicators

Ismatova

Yuldasheva

2023

“…The measurements were carried out at an air flow velocity in the range from 1.1 to 30 m/s. The measurements were carried out on an installation for extracting fibrous materials from dusty air [12,13].…”

Section: Figure 1 Pneumatic Conduit (Pipe) Formsmentioning

confidence: 99%

Investigation of air velocity in expanding and contracting pipes for the transport of fibrous materials

Abbazov

Khodjiev

Salimov

et al. 2023

Uzbekistan is implementing comprehensive measures to produce a wide range of high-quality and inexpensive textile and light industry products based on the production and deep processing of cotton fiber, which is the main textile raw material, to prevent waste and increase its competitiveness. This article, to a certain extent, serves to implement the tasks specified in the Decree of the Cabinet of Ministers dated November 25, 2018 No. 53 “On additional measures to organize the activities of cotton and textile industries and clusters” and other regulatory and legal documents related to this activity. The science of cotton transport by pneumatic transport has a long history, and with an air flow speed of more than 28 m/s, cotton is distributed more evenly over the pipe section. In it, the transportation process is carried out mainly in the suspended state of the material. With a decrease in the air flow velocity from 25.0 m/s, an analysis of the literature on the uneven distribution of material over the pipe section was carried out. It has been practically proven that an increase in the expansion angle in expanding or contracting pipes depends on air resistance, and the expansion or contraction angle depends on the speed of air movement at the point of expansion or contraction of the pipe. Therefore, the optimal value of the angle of expansion or contraction of expanding or contracting pipes was determined.

“…Therefore, in the process of extracting fibrous materials from a mixture of air and fibrous materials, one of the important tasks is to analyze the loss of fibrous materials in the air flow based on the determination of local resistances [11]. Using the results of our previous research on the prevention of local resistance in expanding pipes, we develop recommendations for the prevention of resistance and bending angles in convergent pipes [12].…”

Section: Figure 1 Narrowing Pipe Schemementioning

confidence: 99%

Investigation of local resistance and air velocity in narrowing pipes for the transport of fibrous materials

Abbazov

Sharopov

2023

In the world, one of the main tasks is to improve the quality of cotton and products from it, the introduction of energy and resource-saving technologies and technical means at enterprises, which make it possible to reduce their cost. In the priorities of the Decree of the President of the Republic of Uzbekistan dated January 28, 2022 No. PF-60 “New Development Strategy of the Republic of Uzbekistan for 2022-2026”, the third priority area called “Advanced development of the national economy and ensuring high growth rates” clarifies the inclusion of a number of tasks in the state program. Air pipes are used in most stages of the primary cotton processing process. In this direction, a scientific base is being created to improve the efficiency of the process of transporting fibrous materials by air, special attention is paid to improving product quality and reducing costs through the creation of automated pneumatic transport systems, and the widespread introduction of modern pneumatic equipment and technology into production is accelerating. Although many studies have been done on the loss of fibrous products during the air transport of cotton and cotton products, some fibrous material is released into the atmosphere. To prevent this, it is necessary to determine the aerodynamic resistances that form in the areas of the changed surface of pneumatic transport pipes, and develop recommendations for their reduction. In this article, based on the results of theoretical and practical studies, local resistances are determined in the zones of narrowing of air pipelines of pneumatic transport, and the change in air speed is presented in graphical form.