The author think there are some problems about section characteristics parameters of two criterions of cold bend piling beam,such as accuracy,integrality and rationality of section size.

Cold-roll void forming sheet is an important product in cold-roll forming sheet, which usually includes pipe, square tube, rectangle tube and unusual tube made by special requirements.

Shanghai Institute of Iron & Steel Technology (SIIST for short) once was a dominance enterprise in the cold formed section industry.

The expert system used in pass design of roll-formed shape;