| 摘要 |
<p>The circular cross section of a blast furnace tuyere is varied from entry to exit along its length. It decreases sharply at the front end to about half the normal diameter, and then widens out more gradually until, about half way along, there is a step which connects it to the normal diameter. The constriction, which is built entirely from the upper part of the tuyere, leaves the cross section circular at every point. It increases the velocity of the air passing through it and leads to better atomising and mixing of injected fuels. These are burned more efficiently and the production of soot and its deposition on the walls of the tuyere is considerably reduced. The tuyere is cooled in the normal way by means of a water jacket.</p> |
