H-beams are manufactured by multiple reverse rolling through universal mill and edger. In this process, complexity of relationship among rolling parameters makes it difficult to get H-beams with closed tolerance.
The objectives of this study are to clear the effect of each rolling parameter on dimensions and develop the method for controlling dimensions with accuracy. In this study, the influence coefficients method available for making effects of many parameters clear quantitatively was used to attain the objectives.
Firstly, fundamental equations are made up based on mathematical model of rolling and characteristics of mills such as mill spring.
Secondly, dimensional variation caused by change in rolling conditions was investigated by analysis using fundamental equations and the relation between dimensions and rolling parameters was clarified.
Thirdly, the rule for controlling dimensions was established by applying influence coefficients method to calculate the modified roll gaps for getting H-beams with higher accuracy.
Finally, the application of this method for practical operation verified its validity for rolling H-beams with closed tolerance. Especially, the universal mill with the function for moving upper horizontal roll in the axial direction results in the remarkable improvement for decreasing the deviation among wall thicknesses at four flange parts.
