Production procedure for producing hollow body from e.g. solid bar, involves cooling formation area of solid bar during formation of hollow section in order to improve firmness and ductility of hollow body

摘要

The production procedure involves heating a solid bar (1) before a hollow section is formed in the solid bar. The formation area (16) of the solid bar is cooled during the formation of the hollow section in order to improve the firmness and ductility of the hollow body (17). The temperature distribution during thermal treatment of the hollow body is controlled to improve the durability of the hollow body. An independent claim is also included for a device for producing a hollow body.