As a result of the dissertation work, the actual scientific and technical problem of improving the three-dimensional printing equipment for the manufacture of parts and products of light industry was solved.
Connection of work with scientific programs, plans, topics. One of the sections of the work was carried out within the framework of the agreement on creative commonwealth between PE «Credo» and Khmelnytskyi National University: «Development of equipment for recycling polymer waste from shoe production» (No. 02-2021TS, 0121U110126).
The object of research is processes of three-dimensional printing in the manufacture of parts and products of light industry.
The subject of research is a screw extruder of three-dimensional printing equipment for the manufacture of parts and products of light industry.
The purpose of the dissertation is to improve the three-dimensional printing equipment by installing a screw extruder that uses granules or crushed polymer waste as raw materials for the manufacture of parts and products of light industry.
The scientific novelty of the obtained results is as follows:
‒ regression equations were experimentally obtained for the first time, taking into account the dependence of the volumetric productivity of the screw extruder on the main parameters: the diameter of the crushed polymer waste, the rotation frequency of the screw and the melting temperature of the polymer for two types of plastics - ABS and TPU, which makes it possible to optimize the process of manufacturing parts and products light industry;
‒ the analytical method of determining the main parameters of the screw extruder of three-dimensional printing equipment, which includes the calculation of the nozzle resistance coefficient, volumetric productivity, pressure in the screw channel, and drive power, was further developed, which makes it possible to optimize the structural elements of the extrusion equipment;
‒ a new cooling system for the screw extruder of three-dimensional printing equipment was developed using a thermal barrier and air blowing, and the temperature distribution in its various zones was investigated in the SolidWorks Simulation software environment, which prevents overheating of the polymer material in the loading hopper and supports the stability of the manufacturing process of parts and products;
‒ an experimental study of the characteristics of crushed polymer waste as raw material for a screw extruder of three-dimensional printing equipment was carried out, and a regression model of the dependence of the bulk density on the diameter of the particles, which is important for calculating the pressure in the feed zone of the extruder, was built.
The practical significance of the obtained results lies in the using of improved three-dimensional printing equipment at light industry enterprises and firms specializing in the sale and service of sewing equipment.
The introductory part presents a comprehensive review of the research, includes substantiation of the topicality of the topic, definition of goals and objectives, as well as the connection of the work with scientific plans, programs and topics The goal, object and subject of the research are formulated, scientific novelty and practical application of the work results are described.
In the first chapter, the current state and prospects for the application of three-dimensional printing technologies in light industry are analyzed.
The second section examines the key characteristics of the screw extruder of 3D printing equipment, including a detailed analysis of main parameters in the areas of feeding and dosing. Formulas for determining the volumetric productivity of the extruder are given. A dependence is given to determine the power of the extruder drive.
In the third section, three-dimensional printing equipment with a screw extruder for processing crushed polymers is improved. A screw extruder was developed and manufactured, and its operation was synchronized with the 3D printing equipment. The cooling system of the screw extruder.
In the fourth chapter, the physico-mechanical properties of crushed polymer waste are determined experimentally. Regression equations of volumetric productivity depending on the diameter of the crushed polymer, the rotation frequency of the screw and the melting temperature of the plastic are derived.
In the fifth chapter, experimental studies of the physical and mechanical characteristics of the samples made with the help of volumetric printing equipment from crushed polymer waste are carried out. Ways and examples of its application for the creation of parts and products of light industry are given.
The appendices include scientific publications that reflect the main scientific results of the work: information on the approval of the dissertation results; patent and acts on implementation of work results.
Keywords: light industry, three-dimensional printing, 3D printer, screw extruder.
