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Geometric Characteristic of a Sewing Needle Applied in Clothing Manufacture Technology with Reference to Elastic Critical Statically Balance Loads – A Comparative Study

Hashima Wael A.

Fibres & Textiles in Eastern Europe

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2021

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Vol. 29, no. 3 (147)

86--90

EN

In this work a sewing needle of an industrial commercial sewing machine is investigated from the different points of view of geometrical and critical elastic statistical balance. The dimensions of the sewing needle are l = 60 mm, and ϕ = 2.5 mm and 1.45 mm diameter for the two stepped needle. The needle is treated as a fixed – free end column, with two sections: Ι0 (Ι1) = 1.9615 (Ε – 12) m4 and (Ι2) = 2.0516 (Ε – 13) m4. The upper partial lenght a = 31.2 mm, while the lower partial lenght b = 28.2 mm. The value of the critical load is 110 N, while the Euler load Ρ e = 1112 N, then γ = 3.1796. Another approach was used for a line diagram of the truncated cone of the sewing needle, where the critical load Ρ cr = 57 N, the Euler load Ρ e = 118 N, and γ = 3.13. For the line diagram of a sewing needle with a constant cross-section ϕ = 1.965 mm, l = 7.3185 (Ε – 13) m4, (formula) & η = 2.467. Then Ρ cr = 103 N, Ρ e = 413 N & (formula). For a sewing needle a constant cross-section and the penetration load is uniformly distributed, the geometric characterictic is found to be ῆ = 7.839, γ = 1.22, Ρ cr = Ρ cr(ql)cr = 328 N & q = 5472 N/m (≈6 N/mm). The present work aims to open as yet untouched areas for more and intensive academic and experimental studies, in the field of how penetration forces affect critical loads. The work is the first step in the evaluation of the mechanics of the industrial sewing needle.

PL

W pracy badano igłę do szycia stosowaną w przemysłowej maszynie do szycia. Do badań użyto dwustopniowej igły do szycia o wymiarach: dł. = 60 mm, ϕ = 2.5 mm i średnicy 1.45 mm. Igłę potraktowano jako kolumnę z nieruchomym i wolnym końcem, z dwiema sekcjami: Ι0 (Ι1) = 1.9615 (E – 12) m4 oraz (I2) = 2.0516 (E – 13) m4. Górna długość częściowa wynosiła: a = 31.2 mm, podczas gdy dolna długość częściowa to: b = 28.2 mm. Celem pracy było otwarcie jeszcze nietkniętych obszarów dla bardziej intensywnych badań akademickich i eksperymentalnych w zakresie wpływu sił penetracji na obciążenia krytyczne.

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Comparative Study of Needle Penetration Forces in Sewing Hems on Toweling Terry Fabrics: Influence of Needle Type and Size

Carvalho Manuel, Rocha Ana Maria, Carvalho Helder

Autex Research Journal

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2020

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Vol. 20, no. 2

194--202

EN

In this paper, an industrial case study comparing the use of different needles in the production of hems in towels is presented. The study aims to assess the sewability of the fabrics, quantified by needle penetration forces. The market offers an interesting range of options for the needle, regarding the geometry of the needle point, surface finishing, and sizes. However, in practice, the choice is difficult, namely due to the lack of quantitative data that may support the empirical evaluation made by the sewing technicians. The work aims to assess how the needle type and size relate to the resulting needle penetration forces. Three terry fabric structures, produced by a home textiles manufacturer, were tested using needles of different sizes, points, and coatings. Needle penetration forces were measured on a sewability tester prototype, previously designed and developed, based on an instrumented overedge sewing machine. It was found that needle penetration forces present very significant differences with small size increments, needle coating also influences forces significantly, and different needle points produce only slight differences, significant only on some of the fabrics that were tested.

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Impact of Sewing Needle and Thread on the Technological Process of Sewing Knitwear

Ujević D., Rogale D., Kartal M., Brlobašić Šajatović B.

Fibres & Textiles in Eastern Europe

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2008

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Vol. 16, no. 4 (69)

85--89

EN

The selection of sewing needles, the fineness of sewing thread, relative air humidity, as well as the thickness and density of knitted fabric play a significant role in the technological process of sewing. Damage to knitted fabric loops during sewing are closely connected with sewing needle penetration force and dynamic tension values of the sewing thread. In this research an instrument for measuring the sewing needle penetration force and dynamic sewing thread tension force was designed.

PL

Wybór igły szyjącej, grubość zastosowanej nici, względna wilgotność powietrza, jak również grubość i gęstość szytej dzianiny odgrywają istotna rolę w technologicznym procesie szycia. Uszkodzenia oczek dzianin są ściśle związane z siłą penetracji igły i wartościami dynamicznych naprężeń nici. Dla realizacji badań wykonano specjalny przyrząd mierzący siłę penetracji igły i dynamiczne siły rozciągające występujące w nitce.

4

The Impact of Softeners on the Reduction of Sewing Needle Penetration Force and the Incidence of Loop Damages

Ujević D., Knez B., Grancarić A. M.

Fibres & Textiles in Eastern Europe

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2002

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Vol. 8, no. 2 (37)

46--50

EN

Important characteristics of softening cotton knitted fabrics in the process of knitwear sewing and the influence of softening on the reduction of the sewing needle penetration force (snpf) are presented. The application of a measuring system for testing the snpf is discussed and loop damages are described. The reduction of the snpf and of loop damages in knitwear sewing is investigated by needling and stitching of double-face single-rib cotton knitted fabrics, considering fabric finishing, the type and concentration of the softener used, sewing needle gauges, thread count and the number of fabric layers.

PL

W artykule przedstawiono wpływ zmiękczania zszywanych dzianin bawełnianych na zmniejszenie siły penetracji igły. Opisano zastosowany system pomiarowy dla określania siły penetracji igły oraz ilości uszkodzeń oczek dziewiarskich. Zmniejszenie siły penetracji i ilości uszkodzeń badano na przykładzie bawełnianych dzianin dwuprawych. W badaniach uwzględniono wykończenie dzianiny, typ i stężenie zmiękczacza, numerację igieł, grubość nitki i ilość warstw dzianiny.

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Influence of the Softener and the Sewing Needle on the Quality of Seams in the Production of Knitwear

Ujević D.

Fibres & Textiles in Eastern Europe

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2001

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Vol. 9, no. 2 (33)

35--37

EN

The importance and role of softener for sewing on cotton knitwear is underlined. Choosing the proper kind and appropriate concentration of the softener significantly contributes to the quality of sewn knitwear. The sewing needle, its fineness and the shape of the point also have significant importance. By optimising these, as well as other technical factors, it is possible to obtain high quality of the manufactured knitwear.

PL

W artykule wykazano celowość i znaczenie stosowania zmiękczaczy przy szyciu bawełnianych dzianin. Zastosowanie odpowiedniego rodzaju zmiękczacza i jego stężenia znacznie poprawia jakość szytych dzianin. Duże znaczenie posiada także igła szewna, jej grubość oraz kształt ostrza. Poprzez optymalizację tych wartości oraz innych parametrów można uzyskać wysokiej jakości dzianiny.

6

Influence of the softener and fineness of the sewing needle on the quality of knitwear producing process

Ujević D., Dragčević Z., Rogale D.

Zeszyty Naukowe. Włókiennictwo / Politechnika Łódzka

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2000

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z. 59

61-68

EN

The importance and the role of the softener on the cotton knitwear is described. Choosing the softener and applying appropriate concentration significantly contribute to the quality of the sewing knitwear technical process. The sewing needle, its fineness and shape of the point also have significant importance. Optimising these and other technical factors it is possible to obtain high quality of knitwear producing.