METHOD FOR COLD ROLLING OF SECTION WITH U-SHAPED CROSS SECTION Russian patent published in 2003 - IPC

FIELD: plastic metal working, namely processes for rolling non-ferrous metals and alloys, possibly manufacture of shaped section of copper blank. SUBSTANCE: method comprises steps of changing from stage to stage reduction degree of cross section of blank in system of roll grooved passes in direction normal relative to motion direction of blank; at first stage deforming blank due to lengthwise separating it by means of Y-shaped notch made along vertical axis of blank cross section; forming lateral members of section at reduction degree 55 - 65 % and deformation rate 0.3 -0.6 1/c; at first stage determining bottom thickness of blank cross section according to condition: δ₁ = S(1+h_sect/d_bl) mm,, where δ₁ is bottom thickness of cross section of blank with U-shaped notch; d_bl is diameter of blank; S is bottom of ready section; h_sect is height of ready section; at further deformation stages gradually extending lateral members of blank cross section along height; at said stages performing deformation at reduction degree 11.6 - 35 % and deformation rate 0,34-0,85 c^-1; at final deformation stage opening lateral members of section until forming U-shaped cross section at reduction degree 1-5% and deformation rate 0,25-0,30 c^-1. EFFECT: enhanced efficiency of method due to making section at minimized number of passes. 5 cl, 7 dwg, 1 tbl