METHOD FOR MANUFACTURING CAN LID, CAN LID, AND CAN BODY

摘要

In the elongation processing shown in A, the height of the panel 11 is maintained by supporting the panel 11 from the bottom side, the curled portion 13 is held from the top side and the bottom side, and the movement of the curled portion 13 is restricted in both of the upper direction and the lateral direction. In the elongation processing, external force is applied to the bottom part of the annular groove 12 in the downward direction in this state, and the bottom part of the annular groove 12 is pressed down. Accordingly, the panel 11 is pulled toward the outer direction in the diameter direction of the panel 11, and the tension is generated in the panel 11 as shown by the black arrow, which is intended to reduce distortion of a can lid while reducing formation of shapes in the can lid.