METHOD FOR MAKING PRESERVE CANS BY THINNING WALLS Russian patent published in 2003 - IPC

FIELD: plastic metal working, manufacture of preserve cans having base and tubular body of sheet metal coated with polymeric film at least on one surface. SUBSTANCE: method comprises steps of selecting sheet metal from group including steel sheet, tinned steel sheet and steel sheet coated with chrome-chrome oxide; making circular disc of sheet metal; subjecting circular disc to deep drawing at making cup coated with polymeric film at least on outer surface; then shaping can from cup by thinning wall during one transition at moving cup successively through several rings for thinning wall. Inlet angle α of each successive (at least of three) ring for thinning wall is less than inlet angle α of previous ring. It is possible to use three rings for thinning wall with value α of inlet angle selected according to given relations. EFFECT: enhanced quality of articles, improved strength of used fitting. 7 cl, 2 dwg