| 摘要 |
<p>The device has an upstream pipe (3) supplying a combustion air (19) to an air filter (4), and a downstream pipe (5) supplying the air outside the air filter and to an internal combustion engine e.g. oil engine, of a motor vehicle, where the pipes are made of thermoplastic material e.g. polypropylene. The pipes have outer walls that are in contact with one another along a portion of their length, where the length of the portion is higher than or equal to 10 centimeters and pipes are in the form of a single oval sectioned tube (14).</p> |
