Seamless can body and method for producing seamless can body

Abstract

A method for producing the seamless can body includes forming a metallic blank material into a cup body having a tubular body section, a peripheral bottom section continuing from a lower end of the tubular body section, and a bulging section bulging from the peripheral bottom section toward an opening section by a first height, and pressing down the bulging section such that the bulging section has a second height smaller than the first height, to thereby form a peripheral ground section continuing from the lower end of the tubular body section and a raised bottom section continuing from the peripheral ground section toward a center-axis side. When an outer surface area of the raised bottom section is denoted by A D and an area of a virtual plane an outline of which is defined by the peripheral ground section is denoted by A B , 1.55≥(A D /A B )≥1.40.

1 . A method for producing a seamless can body, the method comprising:
 a first forming step of forming a metallic blank material into a cup body having a tubular body section, a peripheral bottom section continuing from a lower end of the tubular body section, and a bulging section bulging from the peripheral bottom section toward an opening section by a first height; and   a second forming step of pressing down the bulging section in such a manner that the bulging section has a second height smaller than the first height, to thereby form a peripheral ground section continuing from the lower end of the tubular body section and a raised bottom section continuing from the peripheral ground section toward a center-axis side,   wherein, when an outer surface area of the raised bottom section is denoted by A D  and an area of a plane an outline of which is defined by the peripheral ground section is denoted by A B , a relation of
   1.55≥( A   D   /A   B )≥1.40
 
   
       is satisfied. 
     
     
         2 . The method for producing a seamless can body according to  claim 1 , wherein, when a volume of a space surrounded by the plane and the raised bottom section is denoted by V D  and a volume of a metallic member forming the raised bottom section is denoted by V M , a relation of
   26.0≥( V   D   /V   M )≥22.0
   
       is satisfied. 
     
     
         3 . The method for producing a seamless can body according to  claim 1 , wherein, the area of the plane has a circular shape, and the area is defined by a lower end of the peripheral ground section as an outline of the circular area of the plane being formed when the seamless can is placed on a flat surface, the flat surface including the plane. 
     
     
         4 . The method for producing a seamless can body according to  claim 1 , wherein, when a volume of a space surrounded by the plane and the raised bottom section is denoted by VD and a volume of a metallic member forming the raised bottom section is denoted by VM, a relation of
   25.5≥( VD/VM )≥22.0
   
       is satisfied