Manhole sewer pipe opening blockout member

Claim 1

Improved manhole concrete blockout for forming sewer pipe openings in the cast-concrete wall of a manhole where a hole is dug in the ground and at least one vertical hollow form is positioned within the hole and spaced apart from the surface which defines the hole and concrete is poured between the surface which defines the hole and concrete is poured between the surface defining the hole and the form for forming a manhole wall, the improvement comprising a plurality of form sections, means for connecting the sections together so that their outer surfaces can be positioned to become a longitudinal extension of the outer surface of the form, at least one block out member, in the form of a sleeve connected to the outer surface of at least one of the sections and having a connection only to the extension for forming an opening in the manhole structure wall, the end adjacent to the section being shaped to engage and conform to the outer surface of the section and the other end being shaped to conform to and engage the corresponding portion of the surface defining the hole so that an opening in the shape of the blockout member will extend through the wall when it is formed, the outer surface of the blockout member gradually decreasing in cross-section away from the section, and the sections being disconnectable so that when the wall is formed the sections can be removed individually inwardly so that the blockout member can be withdrawn from the opening formed in the wall.