Pipeline Rehabilitation: Getting Started

Polyurea technology is not new to the pipelining industry,
with basic applications dating back more than 20
Years. Much of this work was either done
by hand spraying (large diameter tube) or simplistic
robotic systems for individual shared sections of
pipe. Continued work over the years has shown that in-place
Pipelines can be commercially developed by robotic systems, andmodern work has even demonstrated that in addition to long, straight runs, robotic advancements have allowed for lining both 45° and 90° Radius changes in a pipeline system. Pipelines of nominal diameter( 1 inch or 2.5 cm) Up to 96 inches (2.4 m) can immediately be lined using polyurea spray elastomer technology with robotic applied-ion methods. Robotic application expansion works hand-in-hand with special-performance transformed polyurea systems, which have been rigged, allowing for application thickness of up to at least ones inch in diameter with one single pass. 
In the United States alone, it is calculated to be over $1 trillion will be required over the next 25 years just to restore concealed water and wastewater lines due to age and degeneration 1-3 and almost $350 billion will be necessary to repair clean and truly harness drinking water lines. This does not entail all of the buried and in-use fumes and chemical pipelines that are also impaired by age. Figure 1 is a typical cross-section of water pipe center in a suburban area.

While some feel that corrosion is an indispensable cause of pipeline failures, pipeline flow coercion due to tuberculin-type growth is also
a significant concern. This growth can significantly reduce the pipe diameter, thus affecting liquid flow through the pipe, flow backup, and in the case of potable water lanes, poor water condition and
wretched consumers. Current pipe elements used in most utility sectors in the U.S. are fashioned of cast iron, ductile iron, concrete, steel, some asbestos cement, or PVC (polyvinyl chloride), and will vary by regions of the country. It is written that over 65 percent of
all public pipeline systems are more than 30 years old, with a large bulk being over 50. According to a water central study by the
Utah State University Buried Structures Laboratory, above 8 percent of these systems are exceeding their useful life expectancy in the U.S. market. As corrosion has been the preeminent cause of pipeline system failures, PVC has been confirmed to have the lowest failure standards.
The traditional process of addressing these failures has continued to dig up and replace the corroded pipe. This produces a very large footprint for blasting, is disruptive, and can be a very valuable process. Given the fact that many pipeline systems are a complete maze, crisscrossing with various other pipe lines, many of
which are underneath buildings and other structures, this can be a very impractical process. 
Trenchless Rehab Methods Alternatives to digging up and replacing
pipeline systems are a number of trenchless technology selections that are expanding in use and acceptance. These options can save up to half of the overall cost correlated to conventional trenching systems, and as a result are advantageous to reflect.
Pipe Bursting and Jacking
This system employs requiring a slightly less diameter pipe into the existing host pipe sections. The forced pipe can include
steel, polyethylene (PE) or polypropylene (PP), or PVC.  This method requires an expanded excavation “footprint” for passage to an end of the existing pipe, but not complete excavation. This process is more fitted for straight runs and does not work well for pipe bends.
Cementitious Lining
This process gives for a very economical position, and we all know that concrete is reasonably sound. However, this method cannot be used in hostile (highly acidic) environments or where highly abrasive or erosive activity is present because the concrete can crack over time. To use the cementitious insulation method, cleaning of the host pipe is needed, followed by minimal exterior preparation procedures.


For pre-lining joint sections of pipe, a simple robotic spray head or a retractable lance spray gun can be employed. The pipe is revolved and the spray lance extracted from the pipe. This is a very effective approach and is determined
Cured-In-Place Pipelining (CIPP)
CIPP is an emerging technology that was injected about 20 years ago and has been used quite extensively. A polymer-impregnated “fabric sock” is inserted into the end of a pipe segment and formed in place to the present pipe using hot air or hot water. The standard polymer systems are either epoxy or vinyl ester-based materials. This process covers lateral intrusion but does allow for pipe bands. Because the material sock is of one size in the run, varying pipe diameters in the system cannot be effectively accommodated.
Annular space among the CIPP and the host pipe does exist and can lead to leakages. Sprayed-in-Place Pipelining (SIPP)
A innovative concept than CIPP employs the use of robotic application heads to deposit liquid, thin- and thick-film lining systems to the interior surfaces of fixed pipe. This procedure uses polymer technologies such as epoxy, vinyl ester, polyurethane and polyurea. Because the lining is placed in a spray fashion, parallel tie-ins remain open and cleared. This process can contain various pipe
diameters as well as radius bends. SIPP and Polyurea The use of the polyurea spray technology has proven to be a successful coating type for utilization of SIPP for a mixture of coating and
SPRAYED- IN- PLACE POLYUREA PIPELINING
One way, hand spray application, is well adapted for large diameter pipe systems, but not very practical for smaller diameter pipe parts. A recent study has shown that when the galvanized corrugated pipe is coated or lined with a general polymer or “plastic” system, 75-year life expectancies can be achieved.