The subway is often used in our daily life to get transportation, but you know how difficult it is to bending the top beam of the subway stainless steel car roof?
First, the characteristics of the parts
The stainless steel car roof curved beam is formed by bending a stainless steel plate. The parts are asymmetrical profiles, thin walls (minimum 1mm) and the contours are intersected by multiple curvature radii with a minimum radius of curvature of R = 350 mm.
Stainless steel bending is a functional, aesthetic way to complete many metal design tasks. Bending is often preferable to welded or mechanical connections, as when a seamless design is required, or there is concern about the crevices created by mechanical joints. Crevices can be particularly problematic for the food and pharmaceutical industries since they may introduce contamination.
Further reading：10 Things Everyone Should Know About Curved Steel
Second, technical difficulties
1, smooth intersection of different curvature radii;
2, no wrinkles at a small radius of curvature;
3, asymmetric parts ensure that the processing process is not unstable;
4, the overall remains flat;
The machine in the picture is a profile bending machine manufactured by BIT for the construction of the Chongqing subway project in China. It is not used in the construction of the subway car roof.
Third, the corresponding measures taken during the bending process
1, smooth intersection of different curvature radii, we use a split and adjustable mold to achieve;
2, small curvature is easy to wrinkle, we use the method of adjusting the tension plus auxiliary external force to achieve;
3, asymmetric instability phenomenon, we use the adjustment of the clamping force and apply force on the main force surface and add a shaping surface on the mold to complete;
4, the overall parts are flat, we use measures to improve equipment accuracy, clamping force equalization and other measures to achieve;