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Information × Registration Number 0219U004014, 0116U004565 , R & D reports Title Development of theoretical foundations for the formation and utilization of a solid component of a welding aerosol popup.stage_title Head Vishnyakov V.I., Registration Date 26-02-2019 Organization Ohysical-Chemical Institute of the Environment and Human"s protection popup.description2 The subject of study is the particles and particle fractions of welding fume (WF), prototypes of the reusable respirators for welders and portable filter-ventilation unit with electro-mechanical filter (PFVU-EMF), as well as samples of chemisorbents, catalysts, polymer-composite materials, dyes of paint and varnish materials etc., which were obtained via WF particle fractions used. The research objective is to establish the regularities, to develop a physico-mathematical model of WF particle formation in the metal arc welding and methods of controlling the process of formation and obtaining of WF particles/fractions with given physicochemical properties; to create a new generation of the PFVU-EMF and reusable respirators for welders for providing normalized working conditions of welders and WF recycling on this basis. World first the physical-mathematical model of WF particle formation in the metal arc welding and computer program for calculating the disperse and chemical composition of the WF particles were developed, and experimentally confirmed the possibility of its use in various welding methods and conditions. The regularities of the relationship between the disperse and chemical composition of particles were established. A method for determining the parameters of an ionized multicomponent vapor-gas environment where WF particles are formed was developed. The methods for controlling the process of WF particle formation and their physicochemical properties in gas metal arc welding were substantiated theoretically and experimentally. The design documentation for the PFVU-EMF was developed and prototype was fabricated and tested. When ER 70S-6 welding wire in shielding gas (CO2) and commercial electrodes ANO-4, ANO-21, UONI 13/55 were used for mild steel welding, the PFVU-EMF prototype provides ? 99.6% trapping efficiency and WF separation into 4 fractions by particles size. The experimental batches of WF fraction (2 kg each) were obtained and a correlation between the fractions specific surface area and their chemical and phase composition was found. New experimental data on the relationship between the WF fractions physicochemical properties and their chemisorption ability in the trapping of acid gases and the catalytic activity in the reaction of low-temperature ozone decomposition were obtained and summarized. The dependence of the catalytic activity on the content and size of the magnetite crystallites and WF fractions specific surface area was established. The technologies of obtaining the mixed (on the example of low-pressure polyethylene) and synthetic polymer composite materials with different degree of WF filling, dyes (brown, red-brown) of paint and varnish materials, as well as dispersed catalyst for ozone decomposition and dispersed chemisorbent of acid gases were worked out. Samples of products obtained of industrial and domestic purpose with the use of WF were fabricated, and their operational characteristics were determined. The Specifications (TU U 28.2-01530125-047:2017 "Filter half masks Welder FFP2" and TU U 28.2-01530125-048:2017 "Filter half masks Welder FFGas1P2"), sets of technological and design documentation for manufacturing a new generation of the respirators for welders and workers of related professions, as well as guidance on their operation were developed. A pilot batch of respirators (200 pieces each) was manufactured and their production tests were carried out. Conclusions of the State Sanitary and Epidemiological Expertise of the Ministry of Health of Ukraine about the conformity of respirators with the medical criteria of safety and Specifications on their manufacturing to the requirements of the current sanitary legislation of Ukraine were obtained. The investigation results will be used: in the modeling and prediction of the biological activity of WF particles; in norming the WF threshold limit values concentrations; in sanitary-hygienic estimation of methods and welding conditions, as well as welding materials; at the design of the reusable respirators for welders and the selection of filter materials for their equip. The practical value of the development and implementation of a new generation of the reusable respirators for welders and the PFVU-EMF is to reduce support costs for norming working conditions in the assembly-welding workshops, as well as obtaining a significant ecological-economic effect due to WF fractions involvement for manufacturing the dispersed catalyst for ozone decomposition and dispersed chemisorbent of acid gases, as fillers of polymer composites, dyes of paint and varnish materials, etc. Product Description popup.authors Абрамова Н.М. Абросимова С.С. Дараков Д.С. Дубінина К.В. Еннан А.А.-А. Кіро С.А. Кабаненко Р.В. Опря М.В. Ракитьска Т.Л. Труба А.С. Фирсов А.Г. Шевченко Т.М. popup.nrat_date 2020-04-02 Close