CONCAVE SHEET SECTION Russian patent published in 2006 - IPC B21D13/10 B21D5/06 

FIELD: rolled stock production, possibly manufacture of cold bent sheet sections.

SUBSTANCE: concave bent section is made, mainly of steel with tension strength σ_B ≤ 630 MPa and with thickness S =0.7 - 2.5 mm. Section has lengthwise continuous corrugations with trapezoidal cross section and rounding radiuses between walls and horizontal portions of corrugations. Walls are inclined toward base of corrugations by angle 20 - 25° relative to their vertical axial line. Width of corrugation bases is less than width of their top portions. Height of corrugation h_r consists 0.8 -1.4 of their maximum width. Rounding radius R =( 3.5 - 4.0) S; spacing between corrugations t = (1.4 - 2.8) h_r.

EFFECT: enhanced consumer's properties of sections, lowered metal consumption for making them.

1 dwg, 1 ex