Förfarande och anordning för tillverkning av ett ien rörkonstruktion ingående rör samt ett rör tillverkat enligt förfarandet

摘要

The invention relates to a method and device for manufacturing a closed profile in a profile structure and a closed profile manufactured according to the method. The closed profile used and constituted by a metal material of iron, alloyed with chromium, nickel and carbon in predetermined proportions is plastically formed, wherein a strong strain hardening of the closed profile is obtained.