Page 146 - Trenchless Technology Piping Installation and Inspection

112 Cha pte r T h ree

FIGURE 3.10 Polyurea lining spray head. (Source: 3M Water Infrastructure.)

Advantages Limitations
1. Provides continuous barrier lining and 1. Not fully structural lining
prevents leak and further internal material.
corrosion. 2. Pipe must be dry and
2. Smooth surface improves flow capacity. free from standing water
3. Rapid setting and same day return to during application.
service.
4. Contains no volatile organic compounds
(VOCs)
5. No plugging of service connections.
6. May accommodate bends exceeding 22.5°.
7. Dependent on the manufacturer and
product, may provide a semi-structural
lining (Class III).
TABLE 3.7 Advantages and Limitations for Polyurea Linings

further development in technology in 1980s, polyurethane lining
systems were used successfully in water industry (AWWA-C222,
2008). The major advantages of elastomeric polyurethanes are
their excellent flexibility, elongation properties, and impact and
abrasion resistance.