Page 149 - Trenchless Technology Piping Installation and Inspection

Coatings and Linings for Potable W ater Pipe Distributions 115

Lining rig
Rack-feed boring Air
machine compressor
Umbilical
hose drum
Lined pipe
Cleaning Static mixer section
head

Corrosion/
encrustation
FIGURE 3.12 Schematic view of lining-installation process.

3.18 Comparison of Coating and Lining Methods
Cement-mortar, epoxy, polyurea, and polyurethane are the major
materials available today for potable pipe coating and lining applica-
tions. They provide added benefits of corrosion protection and,
dependent on the product and manufacturer, may provide some
structural enhancements. Certain differences exist between products
due to specific material properties and type and quality of applica-
tions of these products. Table 3.10 present a summary of major differ-
ences for these materials.

Parameter Cement-Mortar Epoxy Polyurea Polyurethane
Corrosion Passive Dielectric Effective Effective and
protection permeable impermeable and corrosion-
barrier barrier corrosion- resistant
resistant barrier
barrier
History AWWA Standard Introduced Has been Has been
since 1955 in U.K. water in use for in use for
ANSI/AWWA industry in the 10 years 65 years;
C602-06 late 1970s; Standard
Standard ANSI/AWWA
ANSI/AWWA C222-08
C-620-07
Pipe Scraper method Rack-feed Drag Drag scraper,
preparation/ boring scraper, power boring,
cleaning power jetting
boring,
jetting
Lining Wet or damp Dry pipe Dry pipe Dry pipe
environment pipe: no required required required
standing water

TABLE 3.10 Cement-Mortar, Epoxy, Polyurea, and Polyurethane Comparison