Tula State University, Tula, Russia

V. D. Kukhar, Doctor of Technical Sciences, Professor
V. A. Korotkov, Senior Researcher of the Department of Mechanics and Plastic Forming Processes, Candidate of Technical Sciences, Associate Professor
S. S. Yakovlev, Teaching Assistant of the Department of Mechanics and Plastic Forming Processes, e-mail: yakovlev-ss-science@yandex.ru
A. A. Shishkina, Master’s Student of the Department of Labor and Environment Protection

The authors conducted experimental studies on a new method of making grooves on the inner surface of the cylindrical shell, involving local plastic forming with a tool of limited length, whose surface was covered with spiral wedge flanges. A developed experimental die was used to study process force and the quality of finished products, describe methods and materials, as well as the results of theoretical studies. A new method implies grooving or making a grid of grooves on the inner surface of pipe shells or workpieces of the shell type using local plastic forming with the rotating tool of limited length. The article contains a diagram of the developed experimental die and the results of studies on its application for grooving the inner surface of the aluminum workpiece, as well as the assessment of process force of all the process operations required for manufacturing products with a grid of grooves. The article presents the figures of semi-finished products with grooves and a part with a grid of grooves, as well as curves of forming process forces. The experiment showed that the best performance was attributed to the operating mandrel of type III, whose forming did not entail front and lateral buil dups of the material, and the part demonstrated the required quality of the surfaces. The research also revealed the dependence between the number of formed grooves or spiral wedge flanges of the operating mandrel and stamping force. The conducted research contributed to drawing conclusions regarding a possibility of applying the developed method for ma king grooved shells and the influence of a shape of an operating mandrel lead-in on process force.

The research was funded by the Russian Science Foundation, grant No. 22-29-20212, https://rscf.ru/project/22-29-20212/, and the Government of the Tula Region.

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