METHOD OF MAKING UNEQUAL-FLANGE Z-SHAPES Russian patent published in 1998 - IPC

FIELD: plastic metal working, namely production of cold bent merchant bars. SUBSTANCE: method comprises steps of bending up strip blank by means of rolls of stands for forming web, flanges and bent portions of said blank. As-formed strip is measured-length cut by shears. Small and large flanges are bent up by angles 18-20^o and 10-15^o respectively at each pass in rough stands. In intermediate stands both flanges are bent by 15-20^o. Web is bent by 2-4^o in each rough and intermediate stands. Diameter of members of upper rolls forming bent portion between small flange and web is sustained constant from one stand to another. Strip is cut simultaneously with elastoplastically bending its web by 4-5. EFFECT: enhanced efficiency. 2 dwg