| 摘要 |
A wire or rod (W) of alloying or treatment substance is fed with gas into a liquid, e.g. metal melt, through a passage in the wall of a vessel (930) containing the liquid. In the passage there is a tube (921) along which the wire (W) passes. Before commencing to introduce the wire (W) to the liquid, the tube (921) has an obturator (910) frictionally fitted at its liquid-confronting end, and the wire is set back from the obturator. The obturator has a nose portion (911) approximately the same diameter as the wire (W) and legs (912) diverging from one another to engage the tube (921). The obturator (910) ensures that before the wire (W) enters the liquid, gas exits from the tube (921) at a speed such that it jets rather than bubbles into the liquid, thereby preventing the liquid from entering the tube. The wire thrusts the obturator (910) into the liquid and then enters itself. |
