Cold-formed section steel, cold-formed rectangular tube contact the outer tube through a one-way roller to form the outer wall, so that the bending moment of strip, bending line will produce cold bending compression, compression effect makes the bending line lengthen longitudinally, the accumulation of bending metal looks thicker, which is the compression/thickening effect of cold forming.


1) The advantages of cold forming are small springback and accurate forming. As long as the roll shape is accurate, the inner angle forming R is more accurate. The advantage is that when cold forming is not possible, it can be formed by cold bending, for example, square and rectangular pipe top/side synchronous bending and finishing. You can also bend R < 0.2T in corners and walls without breaking.
2) Defects of drawing/thinning effect in cold forming. It can produce cold bending and stretching, and shorten the longitudinal length of the stretching and bending line. Secondly, cold bending of metals is caused by stretching and thinning. The disadvantage is that when cold forming, the top/side is cold formed. Because the upper and lower rolls produce pressure at the same time, the forming force is easy to exceed the critical point, resulting in the unstable concave edge, which will also affect the stable operation of the unit and the formation of quality.