METHOD OF MAKING BODY OF METALLIC GAS BOTTLE Russian patent published in 1994 - IPC

FIELD: metal pressure forming. SUBSTANCE: method comprises steps of forming bottoms from measured blanks by multiple drawing without thinning and with thinning of walls, alternating with thermochemical treatment between the above mentioned operations, trimming the bottoms, punching a hole in an upper bottom and welding them. An annealing operation at 350-370 C over 70-90 min is being performed before the welding operation. EFFECT: enhanced efficiency. 1 cl, 2 dwg