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Roll forming is a high production process for forming sheet metal into desired uniform cross-sectional shapes by feeding the metal through successive sets of rotating tools known as form tools. Several parameters, both quantitative and qualitative, ought to be considered while designing roll forming tools, such as section geometry, material properties of the product, number of forming stages, operation sequence, mill parameters and roll profiles. The conventional design methods, however, do not account properly for the interactions between important mechanical and geometrical properties and consequently they may lead to improper flower pattern sequence and roll profiles for the form tools. Although existing Computer Aided Design (CAD) systems provide significant advantages over manual methods, they still require the roll designer to work out separately the drawing details of the cross-section, the roll pass schedule, and the mill parameters. New effective analytical models have been developed and implemented through an interactive, integrated software system in order to overcome the limitations outlined above, both for traditional methods and for existing CAD tools. The new, advanced methodology described in this dissertation brings out the following unrivaled contributions to the current state-of-the art for the roll forming process: (1) Development and implementation of an integrated CAD system for the design of roll forming tools. (2) Identification of the dominant factors influencing the roll forming process. (3) Automatic generation of the flower pattern for various cross-sectional shapes. (4) 3D representation of flower pattern alternatives to provide the roll designer with the capability to visualize easily the forming sequence of any given cross-section. (5) Development of a numerical analysis methodology to diminish and even eliminate section defects of either a geometric or a material nature. (6) Development, verification and application of an expert design system based on methods and guidelines available in roll forming literature, that enable optimal selection of mill parameters for a typical family of cross-sections. The new approach for designing roll forming tools has been validated, along with its supporting software for a typical range of cross-sectional shapes. The results correlate well with reference data, thus demonstrating the high reliability and efficiency of the methodology developed in this research. The integrated CAD system can reduce the time and effort needed for designing roll forming tools, while minimizing the dependency on the experience of any individual designer. It is now possible to define the desired cross section of the final product and subsequently obtain the optimum set of roll profile drawings at all forming stages with less intervention from the user.