METHOD FOR MAKING PARTS WITH VARIABLE-SIGN CURVATURE Russian patent published in 2004 - IPC

FIELD: plastic metal working in machine engineering and building, namely manufacture of parts with variable-sign curvature. SUBSTANCE: method comprises steps of marking out initial blank by portions; placing it and fixing in shaping rolls; bending blank according to its marked out portions during bending-rolling process in roll-type bending machine while realizing intermediate rotation of blank in vertical plane; again guiding blank in rolls and bending its portions with opposite curvature; in order to bend-roll portions of blank with the same sign curvature without separating shaping rolls and without slipping of rolls relative to blank, determining deformation values and setting tuning parameters; gradually moving pressure roll in zone of joining curvilinear portion with rectilinear one during intermittent drawing of blank between shaping rolls according to set tuning parameters. EFFECT: enhanced accuracy of part geometry due to smooth joining of rectilinear and curvilinear zones, improved surface quality, lowered number of technological transitions, increased efficiency of process for making parts with variable-sign curvature and different bending radiuses. 10 dwg, 2 tbl, 1 ex