METHOD FOR MAKING ROLLED PIECES OF BALL BEARING STEELS Russian patent published in 2003 - IPC

FIELD: ferrous metallurgy, namely, modes for deformation-heat treatment of hypereutectoid steels, possibly production of round shapes for making rolling bodies of bearing assemblies. SUBSTANCE: method comprises steps of heating steel ingot until 1240 C, rolling it in blooming mill and continuous bar rolling mill for making square cross section billet; cooling billet at mean rate 6.5 C/h until 200 C in thermostat; then heating it up to 1190 C and rolling in small bar rolling mill to round cross section shape at total elongation degree 56,6 for 15 passes; sustaining temperature of rolling process termination at outlet of last stand equal to 950 C and cooling shape by means of water until 825 C; then coiling it and cooling coil in open air. EFFECT: enhanced quality of rolled bars due to elimination of carbide liquation and stripeness, lowered degree of remained carbide lattice in annealed state. 1 tbl, 1 ex