| 摘要 |
The subject of the invention is an adjustable heavy-duty manhole head, which has a cover (1) and a rectangular cover frame (2). The essence of the invention is that the cover frame (2) has a conical mantle (16) narrowing towards the manhole, and there are pillar-like raising mechanisms in the rectangular corners of the cover frame (2), consisting of a tubular nut (3) and a screw spindle (4), covered by a protecting sleeve (5) fixed by the concrete. |
