使用液压拉伸器时螺柱预紧力回弹分析

Analysis of the Reduction of Bolt Pre-tightening Force When Using the Hydraulic Stretcher

大缸径柴油机通过液压拉伸器拧紧螺母时,施加到螺柱上的预紧力有一定量的回弹量,最终预紧力小于设计值,其差值是设计过程中确定液压拉伸器施加油压大小的重要参考因素。分别采用有限元分析和试验测试的方法对该差值作了对比分析。分析表明:回弹量均为设计值的10%,设计时应预以充分重视。

The final pre-tightening force on the bolt is smaller than the design value,as when the nut is tightened using the Hydraulic Stretcher,there is reduction of bolt pre-tightening force.In the design procedure,the value difference is an important reference in determining the oil pressure applied by the hydraulic stretcher.The methods of the finite element analysis and testing were adopted to study the value difference.The results show that the reduction reaches 10% of the designed value,and shoud be paid attention to.