جستجوی مقالات مرتبط با کلیدواژه "web warping" در نشریات گروه "مکانیک"

Flexible roll forming is a modern process to produce products with variable cross section that can be used in construction and automotive industries. The portion which connects the slim section to the wide one is called transition zone. In this paper, effect of different bend curves on the web warping has been studied in the transition zone. Considering the geometrical boundary conditions of the transition zone, five different curves including circular, quadratic, cubic, quartic, and quintic curves were studied numerically and experimentally. According to the finite element results, longitudinal strains on profile edge which are less than the desirable strain increase the web warping defect. Product with circular bend curve showed the maximum amount of web warping while the quartic bend curve led to the lowest web warping. In order to verify the finite element analysis, the longitudinal edge strain and the web warping were measured in products with Circular bend curve experimentally. A good agreement between the experimental and finite element results confirmed the accuracy of the finite element model.

Flexible roll forming is a modern process for producing profiles with changing cross section. One of the important defects in this process is the web warping of product that causes failure to obtain dimensional and geometrical tolerances. In this paper، mechanism of web warping occurrence was investigated by finite element simulation in ABAQUS/CAE software. Results of simulation indicated that inadequate longitudinal strain in the edge of profile’s flange in transition zone is the reason of profile’s web warping. Furthermore، the effect of geometric parameters of product such as flange length، bend angle، radius of transition zone and thickness on the web warping were determined. Analysis of variance showed flange length and bend angle are recognized as the most effective factors on warping of profiles with specific thickness. An equation for prediction of warping was proposed in terms of geometrical parameters of product. In order to verify the finite element model، the longitudinal strain of deformed strip edge was obtained from simulations and compared with the experimental results of other researchers. A good agreement between them confirmed the accuracy of the finite element model.