| 摘要 |
The cover has supporting frames and a manhole cover held by the supporting frames. A circular seal (6) made from a rubber-like material e.g. silicon, is arranged between the supporting frames and the manhole cover. The seal has lugs (15) that are shiftably arranged to each other at their lower and upper sides, and run in a longitudinal direction of sides of the frames. The manhole cover is wedged with the supporting frames. |
