The Development Of Straightening Technology For W-typed Steel

With the development of science and technology, production cycle is shortening constantly. The priority of steel’s development is being changed from the pursuit of yield to the pursuit of quality with the increasing advance of requirements of the steel quality by enterprise. With the rapid development of industry, a large number of structural sections are used in machine industry, automobile industry, aircraft industry and so on. In the process of sections rolling, especially the slender member which is easy to be bended and distorted, the initial blank will undergo bending deformation with the process of roughing, finishing and heat treatment. So straightening treatment is necessary for these materials. The bending deformation of workpieces has influence on the latter process and application, even leads to a volume of waste products. At present, the straightening theory about structural sections with simple cross-section shape, such as rectangular cross-section, diamond-section, circular-section, has been improved dramatically. But the straightening theory of special-shaped profiles is still imperfect. For example, the straightening parameter and technology are still not determined accurately. Usually, a satisfied parameter can not be obtained even through a trial-and-error procedure.This paper studies the straightening technology of W-shaped steel, whose straightness can not meet production requirement, then acquires rational the straightening parameter and straightening model.This thesis analyses the straightening deformation of W-shaped profiles on the basis of straightening theory and rolling straightening principle. The straightening scheme is determined in accordance with rolling straightening process and the actual condition of sections. Then the straightening modeling is deduced, such as the equation of straightening curvature ratio, bending moment integral equation. The straightening parameters (straightening force and reduction) of W-shaped profiles is obtained through this straightening modeling; The finite element software is used to simulate the straightening process of W-typed profile on the basis of the parameters. It is found that the experimental value has a little error to the theory value. Then the theory value is used in the straightening experiment of factory. The result shows that the straightening parameters above can achieve the the straightening purpose. To a certain degree, the theoretic calculation of the straightening model has a good reliability and the setting of the parameters can meet the requirements of straightening for W-shaped profile。...