State of Technology Report for Force Main Rehabilitation, Final ...

Technology/Method Fold and Form PE Close Fit Liner
Renewal Length, feet 2,000+ feet depending on winching capacity.
Other Notes Pipes may be cleaned, as needed, with high-pressure water jet cleaners,
mechanically powered equipment, and winch cable attached devices or fluidpropelled
pig devices.
III. Technology Design, Installation, and QA/QC Information
Product Standards HDPE is certified as complying with ANSI NSF Standard 61.
Design Standards Class 4 design based on AWWA/PPI design standards. Class 3 interactive design
based on industry accepted design methodology.
Design Life Range 50 years
Installation
Methodology
1. Excavations are required for installation and to remove any existing fittings.
2. The PE pipe selected for the project is welded into lengths suitable for
installation; this can be the entire length, or shorter segments to accommodate
available work space. If shorter segments are used, they will be fused together
prior to entering the folding machine.
3. The welded pipe is pushed through the folding machine, which alters the shape
of the pipe, resulting in a diameter reduction of up to 40% of the cross-sectional
area. The shape is maintained by banding the folded pipe.
4. The liner is inserted into the host pipe.
5. Once the liner is in place, it is cut to length, end fittings are attached and liner is
pressurized to snap the bands.
6. Intermediate fittings are installed, service connections are excavated and
reconnected, and the completed line is pressure tested, disinfected and returned to
service. Access points are backfilled and reinstated.
QA/QC • Prior to installation of InsituGuard, CCTV inspection of the main is needed to
locate any obstructions, protrusion, changes in diameter or in-line valves that
could affect the InsituGuard.
• After installation, InsituGuard is inspected again visually with CCTV, and
any abnormalities are noted.
• For the post-installation pressure test, InsituGuard is subjected to an internal
pressure equal to twice the known operating pressure, or operating pressure
plus 50 psi, whichever is less. After a stabilization period, the test period is
one hour. Limit on make-up water to maintain pressure is 20 gallons per inch
diameter per mile of pipe per day.
IV. Operation and Maintenance Requirements
O&M Needs Before returning the InsituGuard to service, for potable water, the system shall be
Repair Requirements
for Rehabilitated
Sections
disinfected in accordance with local standards.
Excavate, remove the damaged portion of InsituGuard and host pipe (if
necessary), install end couplers and bridge the previously damaged location with
new pipe and couplers as required.
V. Costs
Key Cost Factors The most costly material is the pipe.
Case Study Costs Not available
VI. Data Sources
References http://www.insituform.com/default.aspx
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