OBRABOTKAMETALLOV Vol. 28 No. 2 2026 174 EQUIPMENT. INSTRUMENTS Computer simulation and process engineering for machining thin-walled titanium hemispheres as part of a hybrid robotic module Ayagma Zhargalova 1, a, *, Vadim Skeeba 2, b, **, Gleb Drach 1, c, Alexey Morozov 1, d, Kristina Titova 2, e, Semyon Papko 2, f, Ivan Yulusov 2, g 1 Bauman Moscow State Technical University, 5/1 2nd Baumanskaya St., Moscow, 105005, Russian Federation 2 Novosibirsk State Technical University, 20 Prospekt K. Marksa, Novosibirsk, 630073, Russian Federation a https://orcid.org/0000-0002-6251-1004, azhargalova@bmstu.ru; b https://orcid.org/0000-0002-8242-2295, skeeba_vadim@mail.ru; c https://orcid.org/0009-0005-7618-2896, drach1254@gmail.com; d https://orcid.org/0009-0002-1846-7592, 2809322@gmail.com; e https://orcid.org/0000-0002-2708-3171, krispars@yandex.ru; f https://orcid.org/0009-0004-4512-5963, papko.duty@yandex.ru; g https://orcid.org/0009-0006-7566-6722, yulusov.2017@stud.nstu.ru Obrabotka metallov - Metal Working and Material Science Journal homepage: http://journals.nstu.ru/obrabotka_metallov Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science. 2026 vol. 28 no. 2 pp. 157–178 ISSN: 1994-6309 (print) / 2541-819X (online) DOI: 10.17212/1994-6309-2026-28.2-157-178 ART I CLE I NFO Article history: Received: 27 March 2026 Revised: 07 April 2026 Accepted: 11 April 2026 Available online: 15 June 2026 Keywords: Spherical pressure vessel VT6 titanium alloy (Ti-6Al-4V) Thin-walled hemisphere Hybrid equipment Robotic module Manufacturing process Process route sheet Process tooling and fi xtures Computer simulation SprutCAM Funding This work was supported by the Ministry of Science and Higher Education of the Russian Federation (project FSUN-2026-0005). ABSTRACT Introduction. In aerospace engineering, thin-walled titanium spherical pressure vessels for high-pressure helium storage are manufactured by welding two precision-machined hemispheres. The geometric accuracy of the spherical surfaces and weld edge preparation determine leak tightness and service life under operating pressures up to 34 MPa and temperatures down to −196 °C. Due to their low stiff ness, thin-walled hemispheres make machining critically dependent on locating charts, clamping forces, and cutting conditions. In the context of Industry 4.0 and the growing demand for hybrid equipment that integrates mechanical and surface-thermal operations, the development of modular robotic cells providing multifunctional machining with fewer re-clamping operations and increased fl exibility has become highly relevant. However, existing design methodologies often fail to account for the multitasking nature, the complexity of preliminary studies, and the requirements for modularity and fl exibility. The purpose of this work is to develop a machining process for thin-walled titanium hemispheres of spherical pressure vessels using computer simulation that ensures compliance with spherical surface accuracy and weld edge preparation requirements, and to improve machining effi ciency by minimizing deformation risk, reducing the number of re-clamping operations, and shortening process planning time when integrating the process into a modular robotic cell. Methods. Design and manufacturing requirements for the hemispheres were analyzed; cutting conditions were calculated taking into account the specifi c features of the titanium alloy Ti-6Al-4V machining; equipment was selected through a comparative assessment based on production effi ciency criteria; and the proposed process was verifi ed in the SprutCAM computer-aided process planning (CAPP) system, considering equipment kinematics. Results and Discussion. Surface fi nish and accuracy requirements were established: Ra 0.8 μm for the inner spherical surface and Ra 3.2 μm for the outer spherical surface. A process route sheet was developed to minimize re-clamping operations and reduce the risk of thin-walled shell deformation. Based on production effi ciency criteria, the DN Solutions PUMA VTS 1214M vertical turn-mill center was selected, enabling combined turning and milling operations in a single setup, consistent with integral machining on a CNC lathe platform. A locating chart using a special ring-type axial clamping fi xture was developed and visualized. Machining simulation confi rmed the feasibility of the process route, correct setup planning, and the absence of tool–workpiece–fi xture collisions, and indicated the potential for rapid process implementation. Conclusions. The results contribute to the development of theoretical foundations and conceptual approaches for designing hybrid machine tools that integrate mechanical and surface-thermal processing operations. For citation: Zhargalova A.D., Skeeba V.Yu., Drach G.A., Morozov A.A., Titova K.A., Papko S.S., Yulusov I.S. Computer simulation and process engineering for machining thin-walled titanium hemispheres as part of a hybrid robotic module. Obrabotka metallov (tekhnologiya, oborudovanie, instrumenty) = Metal Working and Material Science, 2026, vol. 28, no. 2, pp. 157–178. DOI: 10.17212/1994-6309-2026-28.2157-178. (In Russian). ______ * Corresponding author Zhargalova Ayağma D., Senior Lecturer N. E. Baumana Moscow State Technical University, 5, 2nd Baumanskaya St., Building 1, 105005, Moscow, Russian Federation Tel.: +7 903 177-52-38, e-mail: azhargalova@bmstu.ru ______ ** Corresponding author Skeeba Vadim Yu., Ph.D. (Engineering), Associate Professor Novosibirsk State Technical University, 20 Prospekt K. Marksa, Novosibirsk, 630073, Russian Federation Tel: +7 383 346-17-79, e-mail: skeeba_vadim@mail.ru
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