| 摘要 |
<p>An apparatus for heating materials such as aluminum billets to a temperature suitable for extrusion is disclosed. The apparatus has at least two zones arranged in tandem, a preheat zone and one or more primary heating zones. Every zone has inner and outer chambers. The outer chamber is supplied with high temperature gas at a pressure in excess of that of the inner chamber. The chambers are separated by baffles which define narrow slot-like aspirating throats through which secondary gases from a secondary source are jetted after entraining high temperature gases from the primary chamber. The secondary gases are at a lower temperature to provide efficient impingement of the gases on a target such as a billet with the primary gases providing the principle heat source. The apparatus is of the closed type utilizing rapid recycling of gases for efficient use of thermal energy.</p> |
