| 摘要 |
The subject of this invention is a sewer ventilation pipe with a vertical pipe (1) protruding above the roof. During cold weather, freezing occurs around the opening of the ventilation pipe, which can completely block the ventilation pipe. The blocking hazard is lessened in this invention by increasing the length of the opening by fitting a horizontal end pipe (2) to the end of the vertical pipe (1), which is open in both ends (3).<IMAGE> |
