摘要
针对螺栓的疲劳性能,采用建立有限元模型的方式进行研究,得到螺栓疲劳失效发生最危险区域为内外螺纹啮合的尾端。在FE-safe中进行疲劳分析,研究应力幅、初始预紧力、偏心载荷、不同规格以及不同表面粗糙度对螺栓疲劳性能的影响。研究结果表明,应力幅越大导致螺栓的疲劳寿命缩短;在一定范围内,初始预紧力的减小导致螺栓疲劳寿命缩短;在偏心载荷的作用下,随着初始预紧力的下降,螺栓载荷应力连续增加,使螺栓对疲劳断裂敏感;螺栓直径和表面粗糙度增大疲劳性能降低。
FEA modelling has been built and introducedin in this paper aiming at investigating bolt fatigue performance and shows the most risky area of bolt which is likely to fail due tofatigue is the contacting surface at the end of internal and external screw. In FE-safe fatigue module,the influence of the stress amplitude,pre-tightening force,eccentric load,various specifications and surface roughness on the fatigue performance of the bolt was analysed,and the simulation results demonstrate that significant stress amplitude and decrease of pre-stressing force reduces the life of bolt. Under eccentric loading,the bolt loading stress increases when the pre-stressing decreases thereby making the bolt is sensitive to fatigue fracture. Rough surface and increase of the bold diameter deteriorate the reliability of the bolt in terms of fatigue.
基金
校企合作基金项目资助(01W10-911-010-OROB)
关键词
螺栓
疲劳寿命
有限元
应力幅
预紧力
bolt
fatigue life
the finite element
stress amplitude
pre-tightening force
