扭转激励下螺纹连接结构动力学行为

Dynamic behavior of thread joint structure under torsional excitation

根据真实螺纹的几何参数,运用Abaqus建立螺纹连接结构的精确有限元模型,采用扭矩法施加预紧力,分析在扭转载荷作用下螺纹连接结构的动力学行为。结果表明:当螺钉与被连接件之间的摩擦力矩小于螺纹接触界面的摩擦力矩时,连接结构在扭转交变载荷作用下容易发生松动;当螺钉与被连接件和内外螺纹2组接触副之间的摩擦因数增大时,螺纹连接结构的摩擦耗散能变化较小,而当被连接件之间的摩擦因数增大时,连接结构的摩擦耗散能呈线性增加;根据三阶修正Iwan模型得到的响应曲线与有限元分析结果吻合。

According to the geometric parameters of real thread,an accurate finite element model for a thread joint structure is created using Abaqus.The preload is generated by applying a torque excitation to the thread,and the dynamic behavior of thread joint structure under torsional load is analyzed.The results show that:the thread joint structure tends to loosen under the torsional alternating loads when the friction moment between the screw and connected piece is less than the friction moment at the thread contact interface;the friction dissipation energy of thread joint structure increases slightly with the increase of the friction factor between the screw and the connected piece,and the friction factor of the 2 groups of contact pairs between the inner and outer thread,while it increases linearly with the increase of the friction factor between the connected pieces;the response curve obtained from the third order modified Iwan model is agreed well with the finite element model.