DIN 2391-81 Part II SEAMLESS PRECISION STEEL TUBES
(cold-finished as-drawn) BK No heat treatment after the last cold-forming process. The tubes therefore have only low deformability. Cold-finished/soft (lightly cold-worked) BKW After the last heat treatment there is a light finishing pass (cold drawing) With proper subsequent processing, the tube can be cold-formed (e.g. bent, expanded) within ...