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Information × Registration Number 0220U100643, 0118U003047 , R & D reports Title Development and research of the technological processes for the manufacture of responsible des-tination forgings for heavy and power engineering. popup.stage_title Head Markov Oleg E., Доктор технічних наук Registration Date 23-01-2020 Organization Donbass State Engineering Academy popup.description2 Object of research: technological processes and tool for forging of large workpieces. Methods of research: theoretical study of stress-strain state of metal carried out by finite element method; experimental verification of the reliability degree of determining stress-strain state was carried out based on the method of coordinate grids. The aime is improving the forging processes of large parts with responsible destination based on the upsetting operation of profiled workpieces. It was found that forging by convex dies with an angle equal to 120 °, increases the level of compressive stress in the axial zone of the workpiece. This facilitate the closure of the axial defect at a reduction of 20 %. Moreover, the axial defect during upsetting is closed at angles of the convex dies α = 120° ... 150 °. A depth of the concavity faces has to d / D = 0.8 ... 0.85. Special methods have been developed for modeling the processes of profiling and precipitation of four-beam blanks based on the FEM, as well as research methods on lead and steel models with an axial hole, modeling axial friability to identify an effective deformation scheme that provides forging of axial defects.The intensive closing of the axial defect during upsetting of the workpiece with concave cross-section occurs at deformation more than 25 %. Steel-samples investigations have concluded that the profiling by convex dies with the angle of 120 ° ensures a complete closing of the workpiece axial defects. Practical recommendations for the profiling ingots to the workpiece with concave cross-section and subsequent upsetting have been designed. Developed new forging processes improved a high quality of large forgings and decline of spoilage from 14 % to 4 %. The mechanical properties of parts increased by an average of 8 ... 11%. Field of application: forging, pressing, stamping, profiling, powder metallurgy.  Product Description popup.authors popup.nrat_date 2020-04-02 Close