METHOD FOR PROFILING EQUAL-FLANGE CHANNEL BARS Russian patent published in 2001 - IPC

FIELD: plastic metal working, namely, manufacture of cold bent rolled bars. SUBSTANCE: method comprises steps of successively bending up members of strip blank by means of rolls having different curvature radiuses in different passes and mounted with predetermined horizontal gaps. At first pass blank is fed between rolls mounted with mutual gap mm; at second pass, with gap δ₂= (0,45...0,55)(δ₁-S)+S,, and at following passes with gap δ = S,, where H and S is, respectively, height and thickness of channel bar, mm; K is factor equal to 0.15-0,17 at ultimate strength of blank σ_в=250-460 MPa and K = 0.18-0.21 in condition when 460 MPa less than σ_в less than or equal to 640 MPa. EFFECT: cracking elimination, simple guiding of blank to roll grooved passes. 1 dwg, 1 ex