US 4,751,799 AGranted

Method and apparatus for lining manhole assemblies and the like

AssigneeA-LOK Product, Inc.

InventorsJack Ditcher, James Westhoff, Eric Ditcher

Life of this patent

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Abstract

Method and apparatus for providing liners in manhole assemblies, which liner is comprised of a plurality of liner sections joined together to form the inner corrosion resistant surface of each manhole member. The liner section define the inner surface of the manhole member being molded. Cast material is poured into the mold and allowed to set. The liner surface engaging the cast material contains integral substantially T-shaped projections which anchor the liner sections to the cast member. The tops and bottoms of each liner section extend around the surface of the section engaging the next adjacent section joined thereto to prevent toxic materials from reaching a cast material. The liner sections are theroplastic vacuum formed whereby the sheet forming the liner section is drawn against substantially T-shaped strips arranged upon the mold member within the vacuum thermo-forming equipment to provide the aforementioned integral T-shaped anchoring projections.

Claims11

Dependent claims

A manhole assembly comprised of a plurality of manhole sections stacked one upon the other;

each of said manhole sections being formed of a cast material and having liner means formed of a sheet-like semi-rigid plastic material having a curved shape for lining the interior cylindrical surface of each manhole section said liner means conforming to the curvature of said cylindrical interior surface;
said liner means having integral, substantially dove-tail shaped projections encircling the curved surface of said liner means engaging said cast material, said integral, curved dove-tail projections conforming to the curved shape of said interior surface and being embedded in said cast material and having a configuration which anchors said liner means to said manhole section;
said manhole section being provided with an engaging annular surface for engaging the adjacent annular surface of the adjacent manhole section;
said liner means having flange means extending over at least a portion of said engaging annular surface whereby the outer surfaces of the flanges of adjacent manhole sections engage one another;
caulking means provided in the region between said engaging flange surfaces to provide in the region between said engaging flange surfaces a corrosion resistant seal to protect said cast material from corrosion;
each of said integral projection means comprising a portion of the sheet-like member which has been formed to yield said projections;
said liner means comprising a plurality of arcuate shaped liner sections;
portions of said adjacent sections being arranged to extend beyond said projections to overlap one another to form a continuous cylindrical-shaped liner for protecting the adjacent surface of the associated manhole section;
caulking means being provided in the region between overlapped portions of said liner sections.

6 more elements

Dependencies are inferred from the claim text.

Facts

Application: 06/883,545Filed 9 Jul 1986
Granted: 21 Jun 1988
Term ends: Not estimatedThe source records don’t support an estimate.

Classification6 codes

B28B 19/0038
Machines or methods for applying the material to surfaces to form a permanent layer thereon: lining the outer wall of hollow objects, e.g. pipes
E02D 29/12
Independent underground or underwater structures ; Retaining walls: manhole shafts; Other inspection or access chambers; Accessories therefor
E02D 29/124
Manhole shafts; Other inspection or access chambers; Accessories therefor: shaft entirely made of synthetic material
E02D 29/125
Manhole shafts; Other inspection or access chambers; Accessories therefor: characterised by the lining of the shaft