摘要 |
A ring manufacturing method of the present invention includes: a laminating step laminating a plurality of metal plates; a junction step jointing the plurality of metal plates by heating and giving pressure; a twisting step heating and twisting the plurality of metal plates after the junction step, an angle stick processing step performing twist processing to the plurality of metal plates to make angle stick shape, a slit formation step forming two longitudinal slits in angle stick component, a ring formation step opening the slits from inside thereof to make two ring components, and a cutting step cutting and separating the two ring components into two rings. |