BENT SECTION Russian patent published in 2000 - IPC

FIELD: plastic metal working, namely, manufacture of cold bent rolled bars. SUBSTANCE: section of low carbon constructional steel with thickness S has cross section with central trapezoidal corrugation with horizontal flanges near its base, lateral inclined webs and portions bent by predetermined radius R. Central corrugation has height more than that of webs by 3.5-4 times and with inclination angle of faces relative to horizon more than inclination angle of webs by 1.25-1.35 times. In middle of flange there is one semicircular corrugation whose direction coincides with direction of central corrugation and whose radius coinciding with depth of corrugation is equal to (2.2-2.5)S. Value R = (2.7-3.3)S. EFFECT: enhanced accuracy and quality of bent sections. 2 cl, 1 dwg, 1 ex