In The Process Of Plate Straightening Mechanism Of The Change Of The Stress Neutral Layer Position Is Studied

In accurate roller straightening theory, the stress neutral layer offset is nottaken into consideration in leveling model, leading to inaccurate intermesh andleveling forces,which affects the development of straightening theory andreduces the straighter production capacity.So,it is necessary to study the neutrallayer offset in straightening process.Firstly, this paper researched the classic rolled straightening theory,determined the calculating method of main parameters,such as bending rollervalues,leveling forces,bending curvatures and so on.At the same time,therelationship between every parameters was analysed and deduced.According to dynamic plate leveling model,the stress and strain of platewere analysed in straightening process and the location of stress neutral layerwere obtained separately by theoretical derivation and finite elementsimulation.The simulation result indicated that the stress neutral layer had offsetin straightening process and the formula of neutral layer offset was given.Thechange rules of the values of stress neutral layer offset were compared underdifferent levelling forces and intermesh. These rules also were tested byexperiments.Then this paper analysed the phenomenon of stress neutral layeroffset in two cases,one was that the value of neutral layer offset of the wholeplate at a time in leveling process;another was that the value of neutral layeroffset of a length of plate form the beginning of leveling process to the end.Andthe curve of the value of stress neutral layer offset was obtained,which couldshow the rule of stress neutral layer offset in leveling process intuitively.Atlast,this paper analysed the affect of stress neutral layer on plate straighteningeffect.The theoretical basis was provided to improve the mathematical model ofstraightening force in straightening process and determine the intermeshaccurately.