Research on the manufacture and strength of the innovative joint of FRP machine parts

Abstract

This paper is devoted to a detachable fiber-reinforced plastic (FRP) machine parts joint of a new type along with its pull-through strength investigation. The relevance consists of a new mechanical processing technology proposition with the accompanying research into thread helical surfaces strength, which in turn benefits in a significant increase in strength compared to conventional thread joints. The paper presents a numerical experiment carried out with finite element method simulation using LS-DYNA. The helical surfaces contact problem of the rigid threaded insert pulled through the FRP thick cylindrical screw nut with constant velocity has been solved. Technology features of the mechanical processing form-generating method, which forms a threaded surface in one passage of the simple geometry tool are also revealed. The research is concluded with the physical experiment of the steel threaded insert pulled through internal thread made in the FRP thick plate with the pull-through test machine, complete with results statistical assessment was obtained by simulation and testing. It is shown that the combination of the new processing technology with the new geometry of the threaded joint makes it possible to significantly surpass pull-through ultimate strength in comparison with modern analogues of metric threads made in parts directly and even with threaded inserts.