Study of the parameters of rational stretching of shoe upper blanks during last formation

This work aims to improve the technology and equipment for forming shoe upper blanks on a last. One of the significant drawbacks of forming shoe uppers using the covering tightening method on ZNK-type machines is the uneven distribution of deformations across the toe-tuft portion of the upper blank. Specifically, the vamp exhibits the greatest transverse deformations along the contours of the forming surface of the last in its peripheral areas, where the elongation of the blank is greatest and can exceed the deformation values in the central part of the vamp by 3-4 times or more. Furthermore, the blank exhibits the greatest average (over the vamp width) transverse elongations in the toe area, which also decreases several times as it approaches the tufts. The existing uneven distribution of elongation across the upper blank area during the covering- tightening forming method results in the leather's valuable properties not being fully utilized in areas of the upper blank with insufficient stretch. This article is based on the authors' research into developing new methods and improving devices for stretch-stretch operations in footwear production. To more evenly distribute deformations across the toe-tuft portion of the upper blank, an improved insole stop design is proposed, providing additional stretching of the vamp in the tuft zone. Uniform stretching of the upper blank along the contours of the forming surface of the last (punch) is achieved through new methods of uneven heating of the blank and uneven moistening of the forepart of the upper blank. The aim of this study is to improve the dimensional stability of manufactured footwear and reduce the consumption of upper leather by using scientifically substantiated dimensions of the initial blank area, taking into account rational deformation, the configuration of the enveloping contour of the forming surface of the shoe last (punch), etc. This study was conducted using a computational and analytical method based on advanced methods and equipment for implementing the technological process of forming shoe upper blanks on a last (punch). The results of this study will improve the quality of manufactured footwear, reduce their cost through scientifically substantiated design of rational dimensions and area of the initial upper blank, and improve the equipment for forming shoe upper blanks on a last.

1. Firtikiadis, Lazaros, Athanasios Manavis, Panagiotis Kyratsis, and Nikolaos Efkolidis. 2024. "Product Design Trends within the Footwear Industry: A Review" Designs 8, no. 3: 49. https://doi.org/10.3390/designs8030049.

2. Zholomanov, N.M., Kim, F.I. Ob odnom metode povysheniya kachestva formovaniya nosochnopuchkovoy chasti zagotovki verkha obuvi [On one method of improving the quality of forming the toevamp part of the shoe upper blank] // Materialy Mezhdunarodnoy nauchno-prakticheskoy konferentsii «Chetvertaya promyshlennaya revolyutsiya i innovatsionnye tekhnologii», posvyashchennoy 100- letiyu so dnya rozhdeniya obshchenatsional'nogo lidera Geydara Aliyeva (3–4 maya 2023 g.). — Gyandzha: Az.TU, 2023. — S. 3–4. (In Russian)

3. Kan, V.A., Kim, F.I. Mashina dlya formovaniya nosochno-puchkovoy chasti zagotovki verkha obuvi [Machine for forming the toe-vamp part of the shoe upper blank] // Predvaritel'nyy patent RK № 13744. — Opubl. v B.I., 2003, № 12. (In Russian)

4. Inkarov, B.G., Kim, F.I., Tyan, A.A. Sposob predvaritel'nogo formovaniya soyuzki [Method of preliminary forming of the vamp] // Predvaritel'nyy patent RK № 13485. — Opubl. v B.I., 2003, № 10. (In Russian)

5. Kim, F.I., Lebedev, V.S., Maradzhapov, I.K. Sposob predvaritel'nogo formovaniya nosochnopuchkovoy chasti zagotovki verkha obuvi [Method of preliminary forming of the toe-vamp part of the shoe upper blank] // A.s. SSSR № 991999. — Opubl. v B.I., 1983, № 4. (In Russian)

6. Kim, F.I., Ermekbaeva, D.B., Zubov, V.Yu. Sposob uvlazhneniya nosochno-puchkovoy chasti zagotovki verkha obuvi pered formovaniem i ustroystvo dlya ego osushchestvleniya [Method of humidifying the toe-vamp part of the shoe upper blank before forming and a device for its implementation] // Predvaritel'nyy patent RK № 15564. — Opubl. v B.I., 2003, № 10. (In Russian)

7. Kim, F.I., Abenova, I.R. Sposob upravleniya raspredeleniem deformatsiy v zagotovke verkha obuvi pri formovanii na kolodke [Method of controlling the distribution of deformations in the shoe upper blank during forming on a last] // Collection of Materials of the International Scientific-Practical Conference “Innovative Solutions of Technological and Environmental Problems in Agriculture, Cotton and Light Industry”. — November 15, 2024. — S. 352–357. (In Russian)

8. Seul, Arina et al. “The Influence of Materials on Footwear Behaviour: A Finite Element Simulation Study.” Materials (Basel, Switzerland) vol. 16,22 7203. 17 Nov. 2023, DOI:10.3390/ma16227203.

9. Borozda, V.D., Burkin, A.N., Dmitriev, A.P., Tsobanova, N.V. Opredelenie ratsional'nykh rezhimov tekhnologicheskogo protsessa formovaniya zagotovok verkha obuvi [Determination of rational modes of the technological process of forming shoe upper blanks] // Izvestiya vysshikh uchebnykh zavedeniy. Tekhnologiya legkoy promyshlennosti. — 2020. — № 3. (In Russian)

10. Siparov, G.V., Burkin, A.N., Kozlov, A.Z., Matveev, V.L. Mekhanizm kleshchey obtyazhnozatyazhnogo agregata [Mechanism of the lasting machine's pincers] // A.s. SSSR № 867365. — Opubl. 30.09.1981. — Byul. № 36. (In Russian)

11. Skidan Vladyslava, Yefimchuk Halyna, Mytelska Olena, Pavlenko Volodymyr, Smykalo Kateryna. (2021). Designing of the shoe upper using modern information and computer technologies. Leather and Footwear Journal. 21. 257-266. 10.24264/lfj.21.4.6. DOI:10.24264/lfj.21.4.6.

12. Hasan, Muhammad Naimul et al. Mathematical model for footwear upper material consumption estimation. Heliyon, Volume 10, Issue 10, e31046, DOI: 10.1016/j.heliyon. 2024. e27077.

13. Chahine Ghimouz, Jean Pierre Kenné, Lucas A. Hof, On sustainable design and manufacturing for the footwear industry – Towards circular manufacturing, Materials & Design, Volume 233, 2023, 112224, ISSN 0264 - 1275, https://doi.org/10.1016/j.matdes. 2023. 112224.

14. Kim, F.I. Approksimatsiya ogibae-mykh konturov formiruyushchey poverkhnosti nosochno - puchkovoy chasti obuvnoy kolodki [Approximation of the envelope contours of the forming surface of the toevamp part of a shoe last] // Materialy Mezhdunarodnoy nauchno-prakticheskoy konferentsii «Innovatsionnoe razvitie pishchevoy, legkoy pro-myshlennosti v industrii gostepriimstva», posvyash-chennoy 65-letiyu Almatinskogo tekhnologicheskogo universiteta. — Almaty: AO «ATU», 2022. — S. 235–237. (In Russian)

15. Kim, F.I., Lebedev, V.S. Vliyanie temperatury na usilie i deformatsiyu kozhi pri rastryazhenii [Influence of temperature on the force and deformation of leather during stretching] // Kozhevenno-obuvnaya promyshlennost'. — 1980. — № 2. — S. 59–61. (In Russian)