GRAFİT VE BRONZ DOLGULU BİR PTFE KAYMALI YATAĞIN KURU SÜRTÜNME ÖZELLİKLERİNİN İNCELENMESİ

PTFE, öncelikle düşük bir sürtünme katsayısına sahip olması ve çok geniş bir sıcaklık sahası boyunca stick-slip hareketine maruz kalmaması nedeniyle kuru yatak malzemesi olarak yaygın bir şekilde kullanılmaktadır. Bu çalışmada grafit ve bronz katkılı PTFE'den imal edilmiş bir kaymalı yatak burcunun çelik bir muyluya karşı sürtünme katsayısı bir deney düzeneğinde tayin edilip, hız ve sıcaklık artışıyla değişimleri incelenmiştir. Deneyler sonucu sürtünme katsayısının nisbeten küçük hız ve basınçlar sahasında hemen hemen sabit kaldığı (yaklaşık 0,19) ve sürtünme katsayısı üzerinde sıcaklık artışının hız artışına göre daha etkili olduğu bulunmuştur. Ayrıca sabit bir pv değeri için belirli bir sıcaklığa kadar "küçük hız + büyük basınç" kombinasyonunun daha düşük sürtünme katsayıları sağladığı bulunmuştur.

Anahtar Kelimeler:

Ptfe, grafit, bronz, kaymalı yatak, sürtünme katsayısı

Investigation of dry friction properties of graphite and bronze filled PTFE journal bearing

PTFE is widely used as a dry-bearing material since it does not subject to the stick-slip motion along the wide temperature range, and has a low coefficient of friction. In this study, the coefficient of friction between the bearing sleeve made of graphite and bronze filled PTFE compound and the steel journal is determined on a test rig and then its dependence upon the velocity and temperature increase is investigated. As a result of the tests, it was found that the coefficient of friction was almost constant (about 0.19) in the relatively small velocity and pressure area and the temperature increase over the coefficient of friction was more effective than the increase in velocity. It has also been found that the combination of "small velocity + large pressure" up to a certain temperature for a constant pv value provides lower friction coefficients.

Keywords:

PTFE, graphite, bronze, journal bearing, the coefficient of friction,

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