METHOD FOR MAKING METALLIC BOTTLES Russian patent published in 2001 - IPC

FIELD: plastic metal working, namely, processes for making cylindrical bottles with convex bottoms widely used in different industry branches as reservoirs for gas and liquid. SUBSTANCE: method comprises steps of using inner base ring with cone end portions and mean basic cylindrical portion; providing lower limit of allowance for outer diameter of said ring the same as upper limit of allowance for inner diameters of bottom beads; at assembling operation shifting edges of bottom beads onto base ring by means of axial motion; forming recess whose size is equal to gap width along the whole perimeter of base ring in zone of welded seam. EFFECT: improved quality of welded seam along its whole thickness and perimeter. 3 cl, 7 dwg