In the threaded connection,the contact surface of the nut and the bolt is complex,it is difficult to analyze the stress state on the thread teeth,and different processing methods have a greater impact on the failure load of the internal thread.It es-tablishes a simplified mechanical model and a finite element model of threaded connection,analyzes the surface stress distribu-tion of the internal thread,and focuses on the experimental analysis of the mechanical properties of cold-extruded internal threads,and compares the mechanical properties with the mechanical properties of cutting internal threads.The results show that the stress concentration and plastic deformation of the internal thread under load are mainly concentrated at the roots of the nuts and bolts and the crests of the first to third threads.The magnitude of stress and the amount of deformation gradually decrease in the opposite direction of the load.The connection strength of extruded internal threads is significantly higher than that of cutting internal threads,and the failure load is increased by 18%to 58.6%compared with cutting internal threads.As the high rate of internal thread increases from 65%to 80%,the mechanical properties of extruded internal thread and cutting internal thread in-crease,the failure load of cutting internal thread increases by(28.86～55.45)%,and the failure load of extruding internal thread increases by(22.89～41.93)%.
关键词
内螺纹/加工方式/牙高率/应力分布/失效载荷
Key words
Internal Thread/Processing Methods/Tooth High Rate/Stress Distribution/Failure Load
维普
万方数据