Optimizing the load carrying performance of the hydraulic guiding elements with finite elements method

xvi, 55 pages29 cm. 1 CDÖZETHidrolik ve pnömatik sistemlerin uzun süreli sorunsuz çalışmasında önemli bir etkiye sahip olan kılavuz elemanlar, hidrolik ve pnömatik silindirlerde eksene dik olan kuvvetlere direnerek metal-metal temasını önlemek için kullanılır. Kılavuz elemanlarda en sık kullanılan malzemelerden biri olan kompozit malzemelerde, fiber yönelimleri ve takviye malzeme oranları gibi farklı parametreler, ürünün kalitesini ve mukavemetini büyük ölçüde etkiler. Bu çalışmada, kompozit kılavuz elemanların sonlu elemanlar yöntemi kullanılarak malzemeden ürüne geçiş aşamalarının ve Digimat, Moldex3D ve MSC Marc programları kullanılarak simülasyon çalışmaları yapılması amaçlanmıştır. Analiz çalışmaları, kompozit malzeme modellemesinde kullanılan Digimat, plastik enjeksiyon üretiminin simülasyonunda kullanılan Moldex3D ve nihai ürün için doğrusal olmayan analizde kullanılan MSC Marc ile entegre bir şekilde gerçekleştirilmiştir. Yapılan analiz sonucunda ürünün boşluktaki dolum durumu, çekme değeri ve basınç değeri Moldex3D programında görüntülendi. Moldex3D programından dışa aktarılan elyaf oryantasyonları Digimat programında işlendi ve oluşturulan malzeme modeli. Daha sonra hazırlanan malzeme modeli Marc programına aktarılmış, doğrusal olmayan analizler yapılmış ve sonuçlar karşılaştırmalı olarak incelenmiştir. Bu simülasyonların doğrulaması, Kastaş Sızdırmazlık Teknolojileri Test Merkezi'nde yapılan testler ile sağlanmaktadır. Optimizasyon çalışmaları sonucunda kompozit hidrolik taşıyıcı elemanın yük taşıma kabiliyeti artırılmıştır.ABSTRACTGuiding elements, which have an important effect on the long-term trouble-free operation of hydraulic and pneumatic systems, resist the forces perpendicular to the axis in hydraulic and pneumatic cylinders and are used to prevent metal-to-metal contact. In composite materials, which is one of the most frequently used materials in guiding elements, different parameters such as fiber orientations and reinforcement material ratios greatly affect the quality and strength of the product. In this study, it is aimed to analyze the transition steps of composite guiding elements from material to the product by using the finite element method and simulation studies using Digimat, Moldex3D, and MSC Marc programs. The analysis studies were carried out in an integrated manner with Digimat used in composite material modeling, Moldex3D used in simulating plastic injection production, and MSC Marc used in the nonlinear analysis for the final product. As a result of the analysis, the filling status, shrinkage value, and pressure value of the product in the cavity were displayed in the Moldex3D program. The fiber orientations exported from the Moldex3D program were processed in the Digimat program and the material model generated. Then, the prepared material model transferred to the Marc program, nonlinear analysis made, and the results examined comparatively. Validation of these simulations provided by the tests carried out at the Test Center of Kastaş Sealing Technologies. As a result of optimization activities, the load carrying ability of the composite hydraulic bearing element has been increased

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