| 摘要 |
<p>The air ducting comprises a number of sections joined by flanges, one at least having lateral outlet ports. A fixed flange frame (3, 3a, 3b) is mounted at one end only of each section (1, 1a, 1b), the external width and height of which are less than the clear internal dimensions of the next one, so that all sections can be nested together for easy transport. There can be a separate loose flange frame for the opposite end of each section. This frame (4, 4a, 4b) is fixed in position on installation of the conduit.</p> |
