Effect of Pitch Difference on Anti-loosening Performance and Fatigue Strength for High Strength Bolts and Nuts
A slight pitch difference is considered between the bolt and nut in this study.Here,the pitch of nut is α μm larger than the pitch of bolt.In the first place,the distance δ,of nut screwed onto bolt without any prevailing torque,is experimentally and analytically obtained for each level of α.Then,the relationship between axial force and prevailing torque during tightening process is tested.According to the obtained torque-axial force relationship,for four different levels of α,the loosening experiment based on NAS3350 (National Aerospace Standard) is performed,and the loosening and dropping status of the nuts are investigated.Considering both the anti-loosening ability and the clamping ability of the nut,the desirable range of α is discussed.After that,according to the loosening experiment results,three levels of α are selected to make a further study about the effect of the pitch difference on the fatigue life of bolt.The fatigue experiment is performed and the S-N curves are obtained.Finally,the finite element method is used to make a simulation of the fatigue experiment and the mean stress and stress amplitude at each thread bottom of bolt are analyzed.
Bolted Joint Pitch Difference Anti-loosening Performance Fatigue Life
Xin Chen Nao-Aki NODA Yu-Ichiro AKAISHI Yoshikazu SANO Yasushi TAKASE
Department of Mechanical Engineering,Kyushu Institute of Technology,Fukuoka 804-8550,Japan
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）