抄録
The authors tried to work extruded square tube containing a cross rib in the draw bending process. For practical use, high rigidity and three-dimensional bending products, this tube was applied to this process: This report describes as follows; (1) optimization of thickness of a cross rib analyzed by FEM, (2) investigation of buckling and splitting limit of the bending by the experimental results, (3) the effect of tube-comers such as radius (r.) and chamfer in this process. As a result of these investigations, we could develop the frame of a rehabilitated tricycle.
