基于有限元的液压铰接接头拧紧力矩计算

针对基于均匀截面应力的铰接接头拧紧力矩工程计算无法充分考虑径向孔等局部结构应力集中效应,计算结果不准确的问题,建立液压铰接接头拧紧过程静强度计算有限元模型,通过在螺纹段定义固定约束,螺母与基体间定义接触约束,施加拧紧力矩及对应的螺纹预紧力载荷,模拟真实受力工况。依据线性强度计算模型下应力结果与施加载荷成正比的关系,确定材料许用应力对应的拧紧力矩,为铰接接头等存在应力集中结构的及接头类产品拧紧力矩确定和结构设计校核提供参考。

Tightening Torque Calculation of Hydraulic Hinge Fittings Based on FEA

The static strength FEA model of hydraulic hinge fittings tightening procedure was built to solve the problem that engineering calculation method based on uniform section stress distribution assumption could not fully cover the stress concentration factors induced by structures such as radical orifices and failed to obtain proper tightening torque.Fixed and contact constraints were applied to the screw and interfaces of the hexagon head and the frame respectively with the torque and relating screw pretension loads to simulate the real stress state.The proper tightening torque corresponding to the permissible stress was obtained by the calculation results and the proportional relation of stress and loads under the linear model assumption,providing reference to tightening torque confirmation and structure design of fittings with stress concentration including hinge fittings.