| 摘要 |
The cover has a frame and a top cover (5), which has an opening. Brims exist in the area of a manhole covering and are upwardly projected over a covering surface area, frame surface area and or road surface area, where projection is about five millimeter. The cover (5) is rotatably placed on the frame. An elastic seal is arranged between the cover (5) and the frame. A covering rubber brim is arranged between the frame and the covering. |
