Specification 15210 - High Density Polyethylene (HDPE) Pipe, Fittings, And Appurtenances Page 6 of 8
January 2021
3066.21
b. All fasteners and back-up rings shall be Type 316 stainless steel below
grade, and zinc-plated steel above grade.
c. Align flanges or flange/valve connections to provide tight seal.
Gaskets are required for flange/valve connections.
d. US Standard round washers may be used on some flanges when in
accordance with the Manufacturer’s recommendations. Bolts shall be
lubricated in accordance with Manufacturer’s recommendations.
e. Torque flange bolts in sequence and in accordance with the
Manufacturer’s recommendations. Do not over-torque bolts.
CONTRACTOR shall use a torque wrench to tighten all flange
fasteners.
Pull bolt down by degrees to uniform torque in accordance with the
Manufacturer’s recommendations.
Protect below grade bolts and flanges by covering with a 6-mil thick
polyethylene wrap. Duct tape wrap to HDPE pipe.
Electrofusion couplers, where used, shall be installed in accordance with
the Manufacturer’s specifications. The outside diameter of the HDPE pipe
and face shall be prepared in accordance with the Manufacturer’s
recommendations prior to installing the coupler.
Pipe Placement:
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Grade control equipment shall be of the type to accurately maintain design
grades and slopes during installation of pipe.
Unless otherwise specifically stated, install pipe in accordance with the
Manufacturer’s recommendations.
Maximum lengths of fused pipe to be handled as one section shall not
exceed 400 ft and shall be placed according to the Manufacturer’s
recommendations as to pipe size, pipe SDR, and topography so as not to
cause excessive gouging or surface abrasion. Pipe wall gouges deeper than
3/16-in. shall be cause for rejection of the pipe.
Cap pipe sections longer than single joint (usually 40 ft) on both ends
during placement except during fusing operations.
Remove dirt or debris from inside of pipe before backfilling.
Notify ENGINEER prior to installing pipe into trench and allow time for
observation. CONTRACTOR shall correct irregularities identified during
observation.
Complete connections within trench whenever possible to prevent
overstressed connections.
Allow pipe sufficient time to adjust to trench temperature prior to testing,
fusion welding, making segment connections, or backfilling activity.
To reduce branch saddle stress, install saddles at slope equal to and
continuous with connecting pipe.
Install reducers adjacent to laterals and tees unless directed otherwise.
Place pipe system in trench allowing at least 12 in./100 ft for thermal
contraction and expansion.
Trench and backfill soil in accordance with Specification Section 02200.
SANBORN HEAD
