Papers by Keyword: Technology

Abstract: Research on improving petroleum bitumen complex properties by modifying them with polymeric elastomers in the form of rubber waste are given in this article. The purpose of the research is to create a bituminous-rubber composition with an increased set of thermo-physical and physical-mechanical characteristics. The effect of bitumen modification with waste rubber crumb and powder in combination with the addition of taurite on the melting temperature, the degree of crosslinking, toughness and heat resistance of the compositions was studied. The optimal composition of bituminous-rubber compositions modified with taurite with high thermo-physical and physical-mechanical characteristics has been determined.

Abstract: The presented study demonstrates the possibility of an analytical approach called the multi-optional hybrid-effectiveness functions uncertainty measure conditional optimization doctrine. This method is applied in order to obtain the known, therefore considered proven, solutions by-passing the entirely probabilistic approach. It is made in application to the stochastic process measures determination. Supposedly, the process is developing in the aircraft engine system’s element (the state condition of its material). The solution is found in the framework of the entropy paradigm. It helps assess the newly emerged materials applications rationality and the novelty technologies implementations expediency on condition of the operational options uncertainty.

Abstract: The article describes the design and purpose of a turbopump unit, in particular, the pump body of the liquid rocket engine turbopump unit. The technology and technological equipment for obtaining complex profile holes in the turbopump units body are presented. The design features of technological process and equipment for electrochemical processing are considered. The proposed technology and devices allows to process parts of the liquid rocket engine turbopump unit with special holes.

Abstract: In the work the bituminous-polymeric composition stable against action of external factors is designed taking into account literature-patent researches and industrial needs. The basic physical-mechanical and thermophysical properties of the designed bituminous-polymeric composition are investigated, and also change of water absorption, shrinkage with time and flammability is studying. The technology of manufacturing bitumen-polymer composition in production is described. The designed bituminous-polymeric composition on some indicators, in particular on heat resistance and flexibility is better than existing analogs that allows its introduction.

Abstract: The article discusses the technologies used in the manufacture of liquid rocket engines filter elements. The analysis of the most widely used methods in the aerospace industry for obtaining grooves and holes in metal filters is carried out, as well as progressive methods for their production are proposed. Special means of technological equipment for the fine filter elements manufacture using electroerosion treatment have been developed.

Abstract: A technology has been developed for the processing recycling of waste - sulfuric cake into building materials with high physical and mechanical characteristics. Sulfur activator (zinc chloride) contributed to the chemical bonding of the components.

Abstract: In the science of car repair, the problem of restoring worn-out crankshafts is very relevant. The engineering solutions proposed in the article will provide an increase in the technical and economic indicators of repair: an increase in the quality of coating by a gas-flame method with a finishing non-abrasive antifriction treatment. At the same time, the engineering solution consisting in the formation of one groove on each journal of the crankshaft, brazing of a copper wire, followed by flame spraying of a coating, sealed by a disk, and grinding of the journals (the bearing supports), provides a non-wear effect. So, thanks to the coil of copper wire, the resource of the crankshaft increases and the cost of repaired crankshafts are reduced in comparison with new ones.

Abstract: The quality of the hot-rolled plate up to 36 mm thick was estimated by the percentage of rolled products, sorted due to the presence of a surface defect "Non-metallic inclusions", and internal defects, detected by ultrasonic plate control. The analysis of the data on the total sorting of hot-rolled plates demonstrated that the amount of sorting differs significantly on the melting from which each series of tubular metal casting commenced, compared to all the other melting in the series. The sorting of the sheets rolled from the metal of the first in a series of melting proved to be 1.9 times higher than that of the metal of all other melts. The main reason (in 68% of cases) of sorting is the presence of non-metallic inclusions on the surface of the plates. The effect of sorting of hot-rolled plates on non-metallic inclusions of various parameters has been studied: the duration of the intermediate ladle-heating; the length of time from the end of the heating of the intermediate ladle, prior to the beginning of the casting; lining temperatures of the intermediate ladle before the beginning of casting; duration of filling the intermediate ladle; the filling rate of the intermediate ladle with metal; mass of metal in the intermediate ladle before the beginning of casting into the crystallizer; chemical composition of metal; overheating of the metal over the liquidus point at the beginning, middle and end of the casting. On the sorting of flat products for non-metallic inclusions, of all the parameters considered, a statistically significant effect is due only to the overheating of the metal above the liquidus point, which varies in the range from 19 to 35 ° C. In order to obtain an acceptable quality of both the surface of slabs and the surface of hot-rolled plates for non-metallic inclusions, the first in a series of melts recommends overheating of the metal in the intermediate ladle above the liquidus temperature of 30-35 ° C.

Abstract: This work presents studies on the material composition and physico-mechanical characteristics of an alumina-containing estimate formed during the production of aluminum on electrolyzers with self-baking anodes during technological operations. The material is a mixture of fine powder 2.5 mm in size (62.78% on average mass) with the presence of pieces of material ranging in size from 0.5 to 6 cm (average 20.26% by weight). The samples contain pieces of hardened aluminum with sizes from 5 to 20 mm (16.96%). The largest content in the sample has the fineness classes-0.315 + 0.16 mm in the volume of 29.85% and the largest class +2.5 mm-37.22%. B It was established that aluminum is concentrated in the fractions-0.315 + 0.16 mm (45.7%) and 0.16 + 0 mm (48.8%), silicon in the fraction-0.63 + 0.315 mm (1.91%), iron at-1.25 + 0.63 mm (0.601%) and-0.63 + 0.315 mm (0.62%). The material consists of cryolite (Na₃AlF₆), chiolite (Al₃F₁₄Na₅), quartz, feldspar, carbonaceous matter and the technogenic phase of the composition (NaF) 1.5CaF₂ AlF₃. The material is characterized as non-abrasive (working index Ai - 0.0184) and very soft in relation to impact crushing (working index CWi - 3.64), the working index of ball grinding Bond (BWi - 6.47) characterizes a very low resistance to ball grinding. The implementation of the crushing operation of an alumina-containing estimate will allow the use of dry cascade-gravity and centrifugal classification to separate impurities in the form of SiO_2, and Fe₂O₃ for the use of alumina-containing material in primary aluminum technology. On the basis of laboratory tests, it is established that alumina-containing raw materials can be separated and photometric and gravitational separation methods can be used. A mathematical model of the motion of particles of primary and prepared alumina-containing raw materials in a cascade-gravity classifier was developed. The criteria and factors characterizing the alumina-containing material, as well as influencing and determining the maximum material enrichment, are established.

Abstract: The paper provides a flow sheet of the phosphorus slag processing to produce precipitated silica (white soot). The process conditions for opening phosphorus slag at the I stage of leaching have been selected: the nitric acid concentration is 3.5 mol/dm³; the ratio S:L = 1:3.5; the temperature is 60 oС; and the process duration is 1 hour. The parameters of the white soot production II stage have been determined: the HNO₃ concentration is 6.5 mol/dm³; the ratio S:L = 1:3.5; the temperature is 50 oС; and the process duration is 1 hour. The temperature effect on the white soot structure and the specific surface have been established. At optimal process parameters, the white soot batches have been obtained with the main SiO₂ component content of 88.2 and 90.5 %, and a specific surface of 170 and 182 m²/g, respectively. The through recovery of silicon into a commercial product is 98.0 % of its initial content in slag.