| 摘要 |
<p>The manhole insert ring (32) of the present invention for manholes is mounted upon the existing cast iron ring (12) so that the composite manhole cover (30) can be rested therein. The ring (32) is preferably a single unit having an inner ring portion with an upper and side surfaces to support the cover and an outer ring portion with a lower surface for supporting the ring upon the iron cast ring (12). The outer ring portion has a peripheral flange that extends several inches outwardly from the inner ring cover support portion. The inner ring portion has a side surface that extends down from the upper flange in which the cover will fit, and an upper surface that extends inwardly from the lower end of the annular side surface to support the cover.</p> |
