Study On Cold Drawing Process Of Rolling Linear Guide Rail

With the continuous development of science and technology,especially the context in which the Industry 4.0 requires a high-degree industrial automation,higher automation requirements for industrial equipment are demanded nowadays.Kinematic pair of rolling linear guide rail will be more and more widely used in automatic production line due to its high interchangeability and high movement efficiency.The roughcast of rolling linear guide rail is traditionally produced in the forging process.As a result,the material utilization rate is low and the production cycle is long.What's more,the accuracy such as the straightness is particularly difficult to ensure.The production of rolling linear guide rail at present mostly adopts the method of cold drawing which not only overcomes the shortcomings of the traditional forging production,but also improves the surface roughness and strength of guide rail.Limited by the process,design level,the domestic manufacturers use cold rolling rolling linear guide,uneven quality,it is difficult to meet the needs of the country.The cold drawing process for rolling linear guide of deformed steel is studied In this paper.The paper introduces the selection of drawing pass and the roughcast for cold drawing according to the characteristics of cross-section size in rolling linear guide rail,gives the transitional cross-section shape of cold drawing by the method of equipotential field and represents the derivation of the formula for calculating the drawing force of cold drawing.A three-dimensional finite element model of rolling linear guide rail is established in the final pass based on cold drawing.The 3D software DEFORM is used to carry out dynamic simulation on the cold drawing process during which the changes of stress and strain in cold drawing process are obtained and the analysis method of evaluation indexes such as straightness,drawing force and residual stress are determined.Through the design of simulation experiment,the influence of the section processing rate on straightness,drawing force and residual stress is obtained and the formula for calculating the drawing force is verified,and the pass processing rates of three colddrawing passes are assigned;The related simulation experiments have been designed to verify the effect of the initial straightness of the bar on the straightness after cold drawing under the conditions where offset differs with same straightness and straightness differs with same deviation.The influence of die's cone angle,drawing speed,friction coefficient and the bearing length on straightness,drawing force and residual stress is verified through orthogonal experiments and optimal combination of parameters is obtained and the bearing length is optimized by using the single factor method.