METHOD FOR CUTTING ROLL-FORMED TROUGH SECTIONS AND FLYING SHEARS TOOL FOR ITS REALIZATION Russian patent published in 1996 - IPC

FIELD: plastic metal working. SUBSTANCE: method refers to manufacture of measured sections of cold-bent merchant profiles. Method lies in successive separation of elements of cut section of profile. In this case, separation is started from both vertical walls, separation of flanges and bottom of profile is started from external edges after walls are cut to 0.45-0.55 of their height. Flying shears tool includes lamella knives, upper one with protrusion and lower one with groove which is manufactured stepped. External edges of upper knife are positioned at an angle of 3-4 deg to horizontal line in direction of lower knife. The angle between mentioned edges and side edges amounts to 91-92 deg. Ratio of widths of groove bottom and lower part of protrusion equals to 1.045-1.055 and ratio of width of upper part of protrusion to distance between stepped protrusions is equal to 1.035-1.045. EFFECT: enhanced efficiency. 1 dwg