Fittings and Specials

Manholes and Appurtences

Manholes and certain appurtenances are necessary for the proper functioning of a complete sewer and culvert system. They may include manholes, inverted siphons, catch basins and inlets, flared end sections, and fittings such as bends, tees, and wyes. The concrete pipe industry has progressively developed most of the common appurtenances and such specials that will provide more efficient and economical facilities for complete performance.

Manholes

ASTM C 478 Precast Reinforced Concrete Manhole Sections
C-478 manhole sections including risers, base sections, and appurtenances such as grade rings and flat slab tops are used in sizes 36" and larger diameters. Also available for large sewers over 3 or 4 ft. in diameter are precast base tees. The riser sections are of circular cross section and may employ an eccentric, concentric cone section or a flat slab top. Cone sections affect the transition from the inside diameter of the riser sections to the top opening.  Flat slab tops are normally used for very shallow manholes. The manhole assembly may be furnished with or without steps inserted into the walls of the sections.
 
A number of joints are used for manhole risers and cones including cement mortar, mastic compound, and rubber gaskets for sealing purposes.
 
Steps are cast, mortared or attached by mechanical means into the wall of the section and may by made of cast iron, galvanized steel, aluminum, wrought iron or approved plastic material.

Catch Basins and Inlets

Catch basins are available in 2'-5' diameters in variable lengths. Inlets are available in 2' diameters in variable lengths. Catch basins and inlets may be manufactured with precast bottom sections. Special precast inlet boxes are also manufactured for use in highway median sloped ditch checks.

Flared End Sections

Precast flared end sections for culverts are manufactured with the groove end on the outlet and tongue end on the inlet section of the culvert in diameters of 12" - 84".

Bends, Tees, Wyes and Curves

Bends are furnished in standard ranges of 15 degrees angular deflections although specials can be manufactured to meet any required deflection. The bend is formed by cutting the pipe barrel to the desired bevel, spot welding, or tying together the exposed reinforcing, and mortising the seams with cement mortar.  Pipe bends should be equal in design strength to the abutting pipe.