BILLET SEPARATION ROLLING METHOD Russian patent published in 2001 - IPC

FIELD: metallurgy, in particular, rolling of paired billets. SUBSTANCE: method involves providing simultaneous rolling of heated paired billets; rolling billets successively in box, diamond and diagonal square passes of rolling mill. After rolling in box-type pass, billets are rolled in forming slitting pass composed of two oval passes joined by connecting member. Paired square billets are separated in slitting pass by means of round combs having radius R=(0.3-0.45)a, where a is square billet side, with following two-strand rolling. Method may be realized by using primary duo-reversing and billet mills, and allows rolled billet twisting around longitudinal axis in diagonal square passes to be eliminated and ingot macrostructure defects to be corrected owing to compacted axial porosity and complete removal of shrinkage carbon liquation. EFFECT: increased efficiency by simultaneous rolling of paired billets, improved quality of ready product by working billet central portions at increased deformation extent. 3 dwg, 1 ex