Research On Minimum Bending Radius And Pressing Down Displacement Of Thin-walled Tube In Its Straightening

Because of its light, sufficient stiffness, strength and toughness, thin-walled tube has been widely used on aerospace, defense, electronic equipment, household appliance and other industries. What’s more, with the rapid development of China’s car industry, there is more and more need of thin-walled tube by people. Various industries make very high demands on the quality of thin-walled tube due to their emphasis on security. In the production of thin-walled tube involved in the internal forces of cold and hot, thin-walled tube bend to varying degree. Therefore, thin-walled tube’s straightening should be put a high value on before leaving the factory and the process of being used.Firstly, the existing strength theory, the pipe cross-section deformation theory, the forming limit theory has been to study in the minimum of thin-walled tube’s bending radius in order to get the maximum of curvature in the way of its being straightened before outcome of the crack in thin-walled tube straightening process, cross-sectional distortion, the inside of wrinkling and other defects. It makes it easier for us to be sure of the anti-bending rate in practical engineering process of straightening. At present, tube has been straightened by straightening machine of inclined roller, traditional straightening machine of more inclined rollers, popular straightening machine of two inclined rollers in recent years. A modified straightening machine of more inclined rollers named straightening machine of eight inclined rollers change its middle two groups of rollers into roller type of straightening machine of two inclined rollers. In order not to affect straightening speed to finish straightening process with high speediness, efficiency and accuracy, it will shorten its middle two groups of rollers and keep crisscross decorates of each rollers of straightening machine of more inclined rollers. This paper have researched the straightening machine of eight inclined rollers on pressing quantity and distances between rollers and other process parameters.