| 摘要 |
Subject: adjustable-in-height covers for manholes of any classes and embodiments (see EN 145 regulation). Constitution: the base 8, the ring 19, the cover bare of holes 17 held in closed position by its own weight or the screwable cover having holes 19 and additional adapters 31,32,33,34,35,36,37,38 being of alternative designing, adjustable in height and destined to be positioned between the base 18 and the ring 19. The placement of adapters (little number of adapters and combination thereof) between the base and the ring allows the accurate raising (over 5 mm) of the manhole to the desired level, in dependence on the state of the road surface. Furthermore, the manholes having screwable cover 39 and special gaskets 40 or other sealing material can exhibit high-tightness properties not provided by existing covers insulated by their weight only. Purpose: manholes coplanar with the road surface; suppression of possible irregularities created on the road surface; enhanced road security. |
