Research on Tight-moment for Screws Used in Airborne Electronic Equipment

The screw thread connection is widely applied to airborne electronic equipment．The value given by the current standard is holding moment，not the tight-moment itself．The magnitude of tight-moment has great effect on the reliability of the screw thread connection．This paper discusses the material screw thread in common use and the common specification screw used in airborne electronic equipment．The factors which influence the magnitudes of tight-moment are analyzed，the holding moments are determined and the tight-moments are calculated．Finally，the magnitudes of tight-moment in different application condition are recommended by means of experiment．This is an important guide for assembly and tight-moment confirmation of airborne electronic equipment．