带预紧力的螺栓连接有限元分析

Finite Element Analysis of Bolted Connections with Pre-tightening Force

在机械通过螺栓连接装配时,绝大数情况螺栓都需要拧紧,使连接在承受工作载荷前,预先受到预紧力作用。施加预紧力的目的在于增加被连接件可靠性和紧密性,防止连接件在工作运转后出现缝隙或相对滑动。基于此,利用ANSYS Workbench软件对法兰用螺栓连接预紧进行有限元分析,证明预紧力可以增加被连接件紧密性;但是当法兰直径过小时,过大预紧力会导致螺栓变形增大,甚至造成螺栓发生塑性变形,而法兰变形也会加大。

When the machine is assembled by bolting, the bolts need to be tightened in most cases, so that the connection is pre-stressed before being subjected to the working load. The purpose of applying the pre-tightening force is to increase the reliability and tightness of the connected member, and to prevent the connector from being cracked or relatively slipped after the working operation. Based on this, the ANSYS Workbench software is used to perform the finite element analysis on the bolt pretightening of the flange, which proves that the pre-tightening force can increase the tightness of the connected parts;however, when the flange diameter is too small, the excessive pre-tightening force will lead to the bolt deformation. Large, and even cause plastic deformation of the bolt, and the deformation of the flange will also increase.