S112024 ダブルナットねじ締結におけるボルトの疲労強度([S11202]機械要素の設計・製造・応用技術(2))

概要

論文の詳細を見る
Bolt/double nuts assemblies are used for preventing the self loosening when the clamp force is relatively low. In general, the fatigue load acting on the bolt increases in bolted joints with low clamp force due to the separation at the contact plane. However, the effect of the locking force on the fatigue strength of the bolt has not yet been clarified. This study aims to clarify the fatigue strength of a bolt in bolt/double nuts assemblies. Fatigue tests were performed for bolt/double nuts assemblies by taking the locking force as a parameter. FE stress analysis was also performed to predict the fatigue strength using Ishibashi's hypothesis concerning the local stress and the fatigue strength of the material. The results show that the locking force in double nuts assembly has the effect to decrease the local mean stress of the fatigue loading on the first thread root of the bolt mating with the lower nut, and this leads to the increase of the fatigue strength of the bolt expressed by the nominal stress or the load amplitude acting on the bolt.
一般社団法人日本機械学会の論文
2011-09-11