Method for the manufacture of a ring part out of sheet metal for a lid of a can

摘要

For the manufacture of a ring part out of a flat sheet-metal part to form a lid for a lid of a can. A hot-sealable coating is provided on one side of the sheet-metal part which is then shaped into a cylindrical tube with the coating being on the inside. The axially extending edges of the tube are joined together to form a butt-joint and the inside surface thereof pressed against a cooling plate. A butt-joint welding seam is then created by means of a laser jet. The tube is separated into equal length tube sections and each is conically enlarged at one end. The other end of each tube section is bent radially inwardly to form a bearing surface for a tear-off foil. By flanging the conically enlarged end, an annular flange is created to receive a body of a can.