摘要 |
The method involves effecting a local temperature change at a hole initiation end (11) of a round heated metallic billet (1) in temperature change zones (110, 112) that are arranged rotationally symmetrical to a central axis (M) of the metallic billet and radially spaced apart from the central axis of the metallic billet, where the temperature change is increase in temperature or decrease in temperature. A jet (21) is projected onto end sides of the metallic billet to generate an exothermic reaction, where a projection element (2) is spaced apart from the metallic billet. The jet is formed as a water jet, an oxygen jet or an electromagnetic beam. An independent claim is also included for a device for producing a hollow metallic billet from a heated metallic billet. |