Analiza vzrokov za nastanek razpoke v zgornji šalčki krmilnega ležaja karbonskega kolesa

Šmon, Valentin (author), Oman, Simon (mentor), Nagode, Marko (co-mentor)

Zaključna naloga zajema analizo razpoke v zgornji šalčki krmilnega ležaja karbonskega kolesa Specialized Enduro 2021. Zanimalo nas je, če je za njen nastanek kriva oblika šalčke ali napačna izbira karbonskega kompozita oz. usmerjenost vlaken. Za analizo smo uporabili predpostavko o homogenosti materiala, izvedli pa smo jo glede na standard testiranja okvirjev koles. Uporabili smo programsko orodje Abaqus, analizo pa izvedli po metodi končnih elementov. Na osnovi rezultatov analize lahko predpostavimo, da so za nastanek razpoke problematične upogibne napetosti v aksialni smeri. Maksimum napetosti se nahaja drugje kot je nastala razpoka. Razpoka je posledica usmerjenosti vlaken.

• Language: Slovenian
• Keywords: okvir gorskega kolesa, analiza poškodbe, vzroki nastanka razpoke, predpostavka homogenosti, metoda končnih elementov, napetostna analiza
• Work type: Final paper
• Typology: 2.11 - Undergraduate Thesis
• Organization: FS - Faculty of Mechanical Engineering
• Place of publishing: Ljubljana
• Publisher: [V. Šmon]
• Year: 2022
• Number of pages: XV, 38 f.
• PID: 20.500.12556/RUL-135933
• UDC: 620.168:620.1(043.2)
• COBISS.SI-ID: 104057859
• Publication date in RUL: 02.04.2022

Secondary language

• Language: English
• Title: Analysis of the reasons for crack initiation in the upper headset bearing cup of a carbon fiber bike

Abstract

The final thesis analyzes the crack in the upper headset bearing cup of a carbon fiber mountain bike Specialized Enduro 2021. We were interested in finding out whether the cup's shape or the wrong choice and orientation of the carbon composite were to blame for its formation. For the analysis, we used the assumption of material homogeneity and performed it accordingly to bicycle safety standard tests. We used the Abaqus software and performed the analysis using the finite element method. The results indicate that bending stress in an axial direction is the most problematic for crack formation. The maximum stress is located elsewhere than the crack has formed and propagated. The crack has appeared due to the orientation of the carbon fibers.

• Keywords: mountain bike frame, crack analysis, causes of cracks, the assumption of homogeneity, the finite element method, stress analysis