|
1.1 Under this item, the contractor shall supply and install
to manufacturer's recommendations an Inflow Protector™ Manhole
Insert as shown on contract drawings and specified hereunder.
MATERIALS & DESIGN
General
2.1 The Inflow Protector™ Manhole
Insert and components shall be manufactured from corrosion-proof
material suitable for atmospheres containing hydrogen sulphide and
dilute sulphuric acid as well as other gases associated with
wastewater collection systems.
The Body
2.2 The insert body shall be made
from Acrylonitrile Butadiene Styrene plastic that meets the Federal
Standards of LP 1183 and can pass the following ASTM test
requirements: D 256, D 638, D 790, D 792, D 785, D 648. The
thickness shall not be less than 3/32" nor greater than 6/32". The
insert body shall be manufactured to the dimensions as shown on the
contract drawings to allow easy installation in the manhole frame.
Gasket
2.3 The gasket shall be made of
closed cell Neoprene. The gasket shall have a pressure sensitive
adhesive on one side and be placed under the insert rim by the
manufacturer. The adhesive shall be compatible with the insert
material so as to form a long-lasting bond in either wet or dry
conditions of use.
Relief Valve
2.4 The gas relief valve shall be
designed to relieve at a pressure of 1 p.s.i. or less. The valve
body shall be made of medium density polyethylene. The venting tube
shall be capable of sealing out dirt and small debris. The valve
shall have leak-down rate not exceeding 10 gallons in 24 hours to
eliminate the ponding of water over the manhole after a rain storm.
The gas relief valve shall have no metal parts.
The valve shall be recessed into the bottom center
of the insert so that it is protected and will not be broken by any
movement of the cover over the valve. This valve configuration will
allow the shallowest practicable insert design, eliminating
unnecessary water retention or weight accumulation. The valve shall
be easily removed for water drainage should inspection be required
immediately after or during rain storm.
Lift Strap
2.5 The insert shall have a lift
strap attached to the body. Lift straps shall be made of 1” width
polyester nylon and shall be seared on all cut ends to prevent
unraveling or deterioration. Lift strap shall be attached to insert
body by means of a sealed 3/16" stainless steel rivet. Attachment of
the lift strap to the insert body shall be in a recess to prevent
contact with manhole cover during removal and replacement of the
manhole cover.
Sizing
2.6 The Inflow Protector™ Manhole
Insert shall be manufactured to fit the manhole frame rim from which
it hangs. Specific field measurements shall be required prior to
production of the insert. Instructions will be made available to the
purchaser or engineer for proper measurements.
INSTALLATION
3.1 The manhole frame rim
shall be cleaned of all dirt or debris before placing the insert
upon the rim.
3.2 The insert
shall be fully seated around the manhole frame rim to retard water
from seeping between the insert and the manhole frame rim.
FIELD TESTING & TRAINING
4.1 After installation the
Inflow Protector™ Manhole Insert shall not infiltrate more than 10
gallons in 24 hou
4.2 No field
training required. |
