Research On The Forming Mechanism Of The Plate Cross Wedge Rolling High-speed Rail Screw Spike

High-speed rail screw spike plays an important role in the rail fastening system, with therise of the train speed, it will withstand greater impacts. And the railway operation safety willbe directly affected by the forming quality of high-speed rail screw spike. Therefore, the high-speed rail screw spike forming technology is particularly important and the key formingtechnology is the threaded portion. Currently, the “forging-rolling” and “forging-cutting”processing methods are always used to form the threaded. However there are high requirementson the control system, the pitch is difficult to control, poor material utilization rate and badmechanical properties, exist in such methods. In this paper, the plate cross wedge rollingtechnology will be adopted to form the efficient near shape high-speed rail screw spike, and doa study on the roll forming technology. The main work is as follows:(1) The main parameters of the high-speed rail screw spike will be designed by referencingto the fasteners technical conditions. Then the plate cross wedge rolling mold parameters willbe obtained, such as the helix angle γ, forming angle α and the broadening angle β. Finally, theentire plate cross wedge rolling mold will be designed.(2) The three-dimensional model of the high-speed rail screw spike cross wedge rollingwill be established by the software Pro/E, and converted into STL format to the DEFORM finiteelement software. Some of the assumptions related to the modeling process were set up, and thematerial model, friction model were established. Finally, the Rigid-plastic finite element modelfor the plate cross wedge rolling screw spike was created.(3) It analysis the four stages’ stress, strain and melt flowing law in the rolling processwhich are wedge stage, engagement stage, the tail forming stage and the end forming stage, byfinite element simulation of the plate wedge cross rolling high-speed rail screw spike. Then therolling deformation mechanism and the reasons for the defects were studied.(4) According to the plate cross wedge rolling mold design of high-speed rail screw spikeand the forming mechanism, this part analysis the deformation mechanism of the three types ofthe trapezoidal, triangular and serrated thread. And the forming characteristics of the monorail,double-track, left-handed and right-hand thread were also analyzed. Last the molded bodywhich has a spiral class rotator feature is summarized. In this paper, through the research of the forming mechanism of the plate cross wedgerolling high speed rail screw spike, for the plate cross wedge rolling process and high-quality,high performance rail screw spike, it lays the foundation.