Influences of Various Factors of Bolt Tightening on Loosening-Fatigue Failure under Transverse Vibration

Our previous study described loosening-fatigue tests under small transverse vibrations that had been performed to elucidate loosening-fatigue mechanism in the long life region. In this study, the influences of various factors of a bolted joint on loosening-fatigue characteristics under transverse vibration have been investigated. Results show that bolt property class has little influence on the transverse loosening-fatigue limits. Results also show that the transverse loosening-fatigue limit is reduced if a bolted joint which has been tightened to within the plastic region is subjected to transverse vibration. And if the grip length and the engaging length are long, the apparent transverse loosening-fatigue limits also decrease.