The Study And Application On Shaping Curve Of The Narrow Step Precision Forming Technology Of The Cross Wedge Rolling

Cross wedge rolling is the main production technology of shaft parts. The mainforming problem is forming quality of the steps of shaft parts in the process of cross wedgerolling. This paper needs to consider rolling problems of the steps and use the shapingcurve to design the mold. In this paper, the problems of accurate shaping of rectangularnarrow step and inclined narrow step within the symmetrical axis is studied.The first, the paper analyzes the geometric configurations of the process of narrowstep. Through simulations obtain the rolling surface variations in the process. According tothe rolling surface variations, rolling process is divided into different phases and works outthe volumes which need to be rolled. According to volume balance principle, it obtains theshaping curve equations. The second, the paper studies the precision forming ofhigh-speed rail screw spike. Because of high-speed rail screw spike playing an importantrole in the rail fastening system and the rise of the train speed, it will stand greater impacts.So the railway operation safety will be directly affected by the forming quality ofhigh-speed rail screw spike. For obtaining the better quality, this paper uses the deducedshaping curve to design the high-speed rail screw spike’s mold. The main work is asfollows:(1) Establishing the the geometric model of the rectangular narrow steps’ forming processand according to rolling surface variations, deduce the shaping curve equations of therectangular narrow steps;.(2) Establishing the the geometric model of the inclined narrow steps’ forming process andaccording to rolling surface variations, deduce the shaping curve equations of theinclined narrow steps;(3) Though the research and analysis of the forming process of high-speed rail screw spike,apply the shaping curve in the forming process and combine with other ways ofcorrection to design the precise forming mold to improve the quality of rail screwspike.This paper studies the precision forming technology of shaft parts. This research has avery important practical significance for improving the precision of geometric shape risingthe level of die design and enhancing the products competitiveness.