IMPROVEMENTS IN THE CONSTRUCTION OF SCREW CONVEYORS USED FOR COTTON SEED TRANSPORT

ABSTRACT

This article discusses the technologies for efficient processing of cotton raw materials, the development of equipment, and the processes for their implementation in production. Additionally, the required capacity for the screw conveyor drive used for transporting cotton with high moisture content is examined. According to the study, when the moisture content of cotton is between 22÷25%, the coefficient of resistance to movement in the screw conveyor increases by 3÷4 times during the cotton transportation process.

АННОТАЦИЯ

В данной статье рассматриваются технологии эффективной переработки хлопкового сырья, разработка оборудования и процессы его внедрения в производство. Также изучена необходимая мощность привода винтового конвейера для транспортировки хлопка с высоким содержанием влаги. Согласно исследованию, при влажности хлопка 22÷25% коэффициент сопротивления перемещению на винтовом конвейере увеличивается в 3÷4 раза в процессе транспортировки.

Keywords: screw conveyor, cotton raw material, cotton fiber, fiber quality.

Ключевые слова: шнековый конвейер, хлопчатобумажное сырье, хлопковое волокно, качество волокна.

Introduction. In the work of Orefise L. and Khinast J.G., a horizontal screw conveyor was developed, and the transport processes of granular materials were studied. It was shown that the efficiency of the conveyor depends on the filling level of the conveyor and the screw rotation speed. In the work of Pezo L. and Jovanovich, a total of 15 one-step horizontal screw conveyors with modified geometry and length were studied. In this study, the effect of changes in the geometry and type of material on the transportation process in the screw conveyors was investigated. Li W. and Qin J. studied the operation of screw conveyors transporting powdery materials and provided theoretical principles for their design.

Methods. In the study of screw conveyors, regression analysis was applied by D.A. Khamidullina, who developed formulas for determining the performance and power consumption of conveyors with five factors using full-factorial experiments. H.M. Mixaylov, in his theoretical and experimental research on screw conveyors in various operational modes, processed the results using the Gagen-Puazey method and recommended three types of conveyors for transporting various dispersed materials.

Results and discussion. The research conducted by D.M. Kobilyanskiy revealed that applying vibration to a screw conveyor increases performance by reducing the circulation of the material being transported. A.Y. Yampolskiy studied the operation of screw conveyors transporting high-moisture cotton, and based on the research, a formula was proposed for determining the required power for transporting wet cotton:

                                                                                      (1)

where Q is the performance, t/s; L is the transport length of the cotton; η is the efficiency coefficient of the screw conveyor drive; R is the resistance coefficient of transporting wet cotton.

When transporting cotton raw materials with a moisture content of 22÷25 %, the resistance coefficient increases by 3÷4 times. The operation of the screw conveyor becomes unreliable when transporting wet cotton, often causing blockages, a decrease in performance, excessive loading of the drive, and possible breakage of the shaft. This indicates that screw conveyors are unsuitable for transporting wet cotton.

The research conducted by SHXR on the operation of screw conveyors in laboratory and industrial conditions is noteworthy. It was emphasized that increasing the screw speed improves the conveyor performance when the moisture content of the cotton raw material does not exceed 20 %. As the moisture content increases, the performance of the screw conveyor decreases under similar conditions.

Further research suggested that for SHX-type screw conveyors, the cotton fiber breakage increases by up to 1,5 % when the transport length exceeds 50 meters, and the breakage of the fiber is directly proportional to the screw speed. Based on the findings, recommendations for new screw conveyor designs were proposed for the cotton cleaning industry.

Q. Jumaniyazov's study on the transportation and distribution system for medium-fiber cotton in cleaning lines and gin battery systems provided insights into alternative screw conveyor designs. A. Sultanov improved the cleaning efficiency of the 6A-12M screw cleaner by applying a new screw design. However, this design led to an increased risk of cotton fiber damage, which hindered its widespread use in the cotton cleaning industry.

Furthermore, for screw conveyors used in the cotton cleaning industry, it was suggested that the screw pitch should be set in the range of 3.5-4.0 times the diameter of the screw. However, this significantly reduces the number of screws, which decreases the fiber agitation, thus reducing cleaning efficiency.

Conclusion

During the research, by analyzing scientific research results, patents, textbooks and training manuals related to the field, the following main conclusions can be drawn.

Optimizing the design of screw conveyors creates the possibility for efficient and safe transportation of cotton seeds. To improve the operational efficiency of the conveyor, it is necessary to enhance materials and technologies, as well as take measures to increase the stability and service life of the conveyor system. Reducing resistance to movement in the cotton raw material transportation process, optimizing energy consumption, and simplifying maintenance are essential. Introducing new technologies to improve the efficiency of conveyor systems could significantly enhance the economic effectiveness of the cotton industry.

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