Shashko Y. Development of the technology for finishing the turbine blades of a turbopump unit, manufactured using the 3D method.

The dissertation work is devoted to the development and implementation of the technology of final processing of turbine blades of turbopump units manufactured by the additive method. One of the main elements of the turbopump unit is the turbine impeller, which is operated under high-temperature loads and are made of heat-resistant materials. In the process of designing turbine discs, great attention is paid to the rational way of fastening the blades from the point of view of structural strength and manufacturability of the structure. Another feature of the production of rocket and space vehicles is the use of a large number of complex technological processes, unique production and testing equipment, which leads to large costs, and as a result, an increase in the cost of products. The domestic rocket and space industry needs deep modernization, namely, productive, cheap methods of manufacturing and processing responsible products, such as blades of closed-type turbines made as one unit with a disk. In the process of developing an effective method for reducing the roughness of closed surfaces of complex turbines, a number of important problems were solved: - a comparative analysis of existing and possible methods of processing the working surfaces of blades and parts of a similar type was performed, on the basis of which the method of abrasive jet finishing was determined and substantiated working surfaces of blades of the closed type (with a bandage), as the most effective; - developed a methodology for assessing the roughness of closed surfaces of turbine blades with a complex profile; - modeling of the process of abrasive blasting using the finite element method was carried out, which made it possible to study the patterns of processing in more detail, to identify key factors affecting the final result, and on their basis choose the most effective processing parameters; - experimental studies of the effect of abrasive material on witness samples were carried out to confirm the effectiveness of the selected processing modes and type of abrasive material; - technological equipment was upgraded, which made it possible to make the process of processing complex profiled closed surfaces of turbine blades more effective and controlled. Thus, in the dissertation work, the actual scientific and practical problem of ensuring the necessary level of roughness of closed surfaces of the turbine in accordance with the requirements is solved design documentation, by developing an effective technology of abrasive blasting.