| 摘要 |
<p>A gas flow duct has two inwardly projecting lips at 180 degrees to each other, surrounded by an outer chamber. It is used as a water trap for gas flow lines, such as engine air intake or exhaust ducts. This simple construction avoids the need for flap valves or cowls for the prevention of e.g. rain water ingress. Two lips are formed in the pipe duct by making angled saw cuts and then pressing the wall inwards at each point so that the lip formed covers practically the whole cross-section of the duct. The two lips are at 180 degrees to each other. A circular chamber surrounds the pipe at this point and is crimped to it at each end. The flowing gas is directed outwards by the first lip, into the chamber, and then back again into the pipe at the second lip. Any water is trapped in the outer chamber and can be run out by suitable connections, which may be through the folds of the crimped sections.</p> |
