Cast iron frame for round manhole cover

摘要

The frame (1) consists of an axially inner annular section (2), an outer annular section (3) of a larger dia., a section coupling shoulder for the cover support, and a top flange section (6). The annular sections are provided with reinforcing ribs. The frame is surrounded by a concrete collar. On the inner annular section outside are formed spaced anchoring ribs (11) in an angled position w.r.t. radial plane. Pref. the outer edges (12) of the anchoring ribs are located on a conical jacket widening in the direction towards the frame top flange.