METHOD FOR STRAIGHTENING ELONGATED CYLINDRICAL PRODUCTS AND MACHINE FOR PERFORMING THE SAME Russian patent published in 1998 - IPC

FIELD: straightening, rolling out elongated cylindrical small-rigidity products and reducing residual stresses in them. SUBSTANCE: method comprises steps of applying static radial reduction effort to elongated blank until straightening it in lower supporting and upper deforming members and also applying axial compression effort. The last effort is applied until occurring in blank stress corresponding to yielding strength of its material while going on to apply radial reduction effort to it. Simultaneously with applying axial compression effort blank may be twisted or rotated around its lengthwise axis. Straightening machine includes housing with two drive holders in the form of cylinders with central openings mounted in said housing with possibility of rotation and lengthwise motion. Collet chuck is arranged inside said opening. Tail portion of said collet chuck is joined with rod of one pair of hydraulic cylinders. Two diametrically arranged levers are mounted on outer surface of said cylinders. Said levers are joined with rods of other pairs of hydraulic cylinders. Rolls of lower pair are stationary and drive ones, rolls of upper pair mounted in casing may be moved relative to blank by means of screw transmission. EFFECT: enhanced efficiency of method, improved design of machine. 4 cl, 5 dwg