Research On Numerical Simulation Of Large Ring Rolling And Wide Spread Deformation

Due to the advantages such as low cost and high efficiency, Ring Rolling are widelyused to produce some kinds of seamless ring parts in recent years,especially large ringparts. But the researches on ring rolling machine and processes for larger than5m indiameter are less. Wide spread is one of the common shape defects in large radial ringrolling, it not only affects the size of ring part, but also can increases machining allowanceand material consumption in later processes, thus increase the cost of production.Therefore, researching the spread formation regularity and influencing factors hasimportant engineering significances to provide basises for determining process parametersand the dimention of blank ring,to provide reference for the formation reasons andpreventions measures of other shape defects, thus improving the quality of ring rolling,According to the equipment and process parameters of a certain factory, this paperestablishes the coupled thermo-mechanical model of ring rolling on MSC.Marc platform.And through the calculation results, it analyzes the regulation of wide spread, which isresearched as the most important, stress,strain and temperature. By changing the modelparameters and a lot of caculations, this paper studies the influences of rolling speed, feedvelocity, axial width, different wall thickness, and different roll size on wide spread. Usingthe data from simulation and through regression analysis to a formula, the paper obtainsthe calculation formula for ring rolling.Based on the spread model of plate and strip and the characteristics of ring rolling,introducing the coefficient kβ, which means the percentage of wide spread in the totaldeformation, this paper establishes a predicting model suitable for ring rolling. It canforecast the average width and diameter size after any cycle. Compared to the ideal data,The datas of diameter and spread based on spread model and spread formula conform tothe pratical rule, the datas are in good agreement.In considering the premise of spread, this paper designs the size and tolerance of thering before and after rolling. The big size make it difficult to find relevant standard,so thevalues of allowance and tolerance can be regarded as reference. In addition to the “fish tail” caused by spread, the paper also studies the forming reasons and preventing measuresof other defects, such as butterfly, taper, elliptical and uneven wall thickness. Which canprovide some references for production.