钛合金干涉螺栓应力波安装质量模拟研究

Installation quality assessment of interference fit titanium bolt in stress-wave driving process by simulations

提高干涉螺栓安装质量是提高螺接接头连接效率的有效途径.为了提高钛合金干涉螺栓安装质量,建立钛合金干涉螺栓有限元动态安装模型,研究干涉量、摩擦因数和安装次数对接头安装质量的影响,并结合试验对安装模型进行验证.结果表明:应力波安装阻力小于强迫安装;1.0%干涉量下安装孔壁挤压不充分,2.0%干涉量时会引起孔壁划伤,1.5%干涉量下安装孔壁表面质量最优;1.0%和1.5%干涉量下安装阻力对摩擦因数不敏感,但干涉量增加到2.0%时,安装阻力和最大凸瘤高度随摩擦因数增大而显著增加;二次安装导致安装阻力和最大凸瘤高度大幅上升,安装孔壁形成明显层叠累积.综上所述,工程实践中推荐使用1.5%干涉量,以保证安装孔壁表面质量.为了提高经济效益,摩擦因数选择0.1~0.15,多次安装应避免使用.干涉量大于1.5%时,应通过多次铰孔、改善螺栓表面润滑效果等方法尽可能降低摩擦因数,进而有效减小安装阻力和最大凸瘤高度.

Improving the installation quality is vital for the design optimization of interference-fit bolted joints. The installation quality of interference-fit titanium bolt using stress-wave driving method was assessed by numerical simulations and tests. The results showed that installation resistance using stress-wave driving method was smaller than that using forced driving method. Small plastic deformation was observed on the mounting hole with interference-fit size of 1.0%, while damage occurred with interference-fit size of 2.0%. Moreover, the best quality was achieved with interference-fit size of 1.5%. The installation resistance for interference-fit sizes of 1.0% and 1.5% showed little sensitivity to friction coefficients, while the installation resistance and peek protuberance height increased significantly with friction coefficient for interference size fit of 2.0%. The twice driving method results in the greater installation resistance, higher protuberance, and lower surface quality. It can be concluded that, the interference fit size of 1.5% is suggested in service to achieve an excellent surface quality of the installation hole after installation, and friction coefficients ranging 0.1-0.15 are also suggested to reduce installation cost without using twice driving method. When interference fit size is larger than 1.5%, the decrease in the friction coefficient is beneficial for the improvement in the installation quality by reducing the installation resistance and peek protuberance height.