Abstract: This paper combines the connecting rod fracture splitting experiment, three-dimensional (3D) reconstruction technology and finite element technique to study the performance of fracture-split connecting rod. The true fracture joint surface of a connecting rod is obtained by fracture splitting, and the fracture joint mode is reconstructed by reverse engineering. A real 3D geometric model of the fracture-split connecting rod is then established. The strength and stiffness of the fracture-split connecting rod are analyzed using finite element simulation and are compared with traditional machining connecting rod. The results show that the static strengths of the fracture slitting connecting rod and the flat incision connecting rod are basically the same. The 3D concavo-convex surface of the fracture-split connecting rod has the bearing capacity, which effectively reduces the shearing stress of the bolt. The fracture-split connecting rod has better shear performance than the flat incision connecting rod. The 3D jagged characteristics of the joint surface can make the rod close contact with the cover and lock each other to reduce the relative movement. The overall deformation of the fracture-split connecting rod is less than the flat incision connecting rod, thus, the stiffness of the fracture-split connecting rod is better than that of flat incision connecting rod.

Key words: machinery manufacturing process and equipment, fracture-split connecting rod, joint surface reconstruction, Non-uniform rational B-splines(NURBS), structural analysis