Demiryolu Araçlarının Kompozit Fren Bloklarında Islak Koşullarda Ortaya Çıkan Fren Zayıflaması Problemi Karşısında Vulkasil Kullanımının İncelenmesi

Öz

Fren balataları üzerine yapılan araştırmalar genellikle kuru koşullar üzerine yoğunlaşsa da, gerçek işletme şartlarında maruz kalınan ıslak koşullar sürtünme katsayısında ciddi düşüşlere ve trafik emniyetini tehdit eden fren zayıflamasına neden olmaktadır. Bu çalışmada, kuru koşullarda yüksek performans gösteren ancak ıslak koşullarda performans kaybı yaşayan K tipi kompozit fren bloğu bileşimine Vulkasil S takviyesi yapılarak bu problemin giderilmesi amaçlanmıştır. Geliştirilen numuneler laboratuvar ortamında fiziksel ve mekanik testlere tabi tutulmuş, atalet tipi dinamometre testleriyle sürtünme performansı değerlendirilmiş; elde edilen bulgular gerçek demiryolu koşullarında gerçekleştirilen saha testleriyle doğrulanmıştır. Deneysel sonuçlar, Vulkasil S içermeyen fren bloklarında ıslak koşullar altında sürtünme katsayısının yaklaşık %20 oranında azaldığını, Vulkasil S takviyeli bloklarda ise bu düşüşün sadece %5 seviyesinde kalarak istikrarlı bir frenleme performansı sağlandığını göstermiştir.

Anahtar Kelimeler

• Vulkasil S
• Blok balata
• Sürtünme katsayısı
• Fren

Destekleyen Kurum

Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK)

Proje Numarası

118G039

Investigation of the Use of Vulkasil Against Brake Weakening Problem Occurring Under Wet Conditions in Composite Brake Blocks of Railway Vehicles

Öz

While research on brake blocks typically focuses on dry conditions, the wet conditions encountered in actual operation cause significant reductions in the coefficient of friction, leading to brake fade that jeopardizes railway operational safety. This study aims to mitigate this issue by reinforcing a K-type composite brake block composition, which performs well in dry conditions but suffers performance loss in wet conditions, with Vulkasil S. The developed specimens underwent physical and mechanical testing in a laboratory setting, were additionally evaluated using an inertia-type dynamometer, and the findings were validated through field tests under real railway conditions. Experimental results demonstrated that the coefficient of friction for brake blocks without Vulkasil S decreased by approximately 20% under wet conditions, whereas Vulkasil S-reinforced blocks limited this reduction to just 5%, thereby ensuring stable braking performance.

Anahtar Kelimeler

• Vulkasil S
• Brake blocks
• Coefficient of friction
• Brake

Destekleyen Kurum

Bu çalışma, Türkiye Bilimsel ve Teknolojik Araştırma Kurumu (TÜBİTAK), Türkiye Raylı Sistem Araçları Sanayii A.Ş. ve Kale Balata tarafından desteklenmiştir [118G039].

Proje Numarası

118G039

Kaynakça

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