Знешкодження газів, які виділяються при литті за моделями, що газифікуються

• Дата: 2023
• Автор: Дорошенко, Володимир
• Формат: Стаття
• Мова: Українська
• Опубліковано: Physico-technological Institute of Metals and Alloys 2023
• Теми: ливарні процеси; лиття за газифікованими моделями; термодеструкція; пінополістирол; нейтралізація газів; шкідливі гази; пропалювання каналів; газовивід
• Онлайн доступ: https://www.metalsandcasting.com/index.php/mcu/article/view/62
• Назва журналу: Metal and Casting of Ukraine

The priority areas of innovation include the widespread use of new technologies for cleaner production and environmental protection. The work is devoted to the technology of Lost Foam casting process (LFC) mainly in vacuum sand molds. Improvements are designed for the manufacture of mainly medium or large castings on single polymer patterns, which are oxidized with the neutralization of gases in sand molds from bulk refractories. For stable combustion of gases in different foundry systems in vacuum molds by removing from the movable gap between the liquid metal and the material of the pattern of gasification products on the upper surface of the mold and burning these gaseous products additionally used a tube through which air flow was fed into this gap. The oxygen of the supplied air partially oxidizes the vapor-gas phase of the pattern's hydrocarbons, and the nitrogen of the air expels the gases before leaving the combustion mold on its surface. At the exit of the mold, the gas burns with an odorless torch with complete neutralization. Combustion of gases outside the mold significantly reduces the power and energy consumption of exhaust ventilation and significantly improves the working conditions in the foundry and has the environmental effect of reducing environmental pollution. Production of exhaust ducts in the pattern by burning is possible for any type of gutter systems. The removal of gas through the channels expands the use of patterns with high-volume density polymers, extrusion polymer made on 3D milling machines, as well as using 3D printing. Examples of patterns for casting with neutralization of gases from gasification of the model are given. In subsequent studies, calculations of air flow in the form are carried out taking into account the thermal balance of oxidation of the products of the model at different oxygen concentrations in the cavity of the form, as well as the creation of an analytical model of gasdynamics of the process for the technical and economic substantiation of recommendations for the casting of different types of castings, species and the temperature of their poured metal, as well as the choice of relevant equipment and instrument.