The Fix Is In:
Preventative maintenance can prevent pipe failure

Cost-effectiveness, non-disruptive working time and sustainability are all key concerns when considering how to fix damaged or failing pipe systems. Downtime, resident displacement and reconstruction are added concerns that should be addressed during the planning process. The cost to fix damaged pipes can be astronomical, especially when the pipes are under tiled floors or behind painted walls.

Pipe systems are often forgotten until there is a problem. Pinhole leaks, corrosion, low flow, root intrusion and infiltration are just some issues that building owners, property managers and engineers commonly run into. Like all tangible objects, pipe systems age and eventually need repairs, but the traditional process of digging up and replacing pipes has more disadvantages than benefits.

However, there are technologies available that can be used as preventative measures against pipe failure. Many plumbing and mechanical companies are adding trenchless technologies to their toolboxes. Pull-in-place structural liners and blown-in epoxy coatings are two pipe lining technologies used worldwide to rehabilitate pipes without destruction. These methods result in less time spent, less mess and lower reconstruction costs.

Pipe lining

It is easy to see the importance of updating pipe systems. Lining companies want to provide cost-effective solutions to owners of buildings and homes, while property owners and managers want a cost-effective way to address their slowly failing infrastructure without destroying their buildings in the process. Old drainpipes can be rehabilitated and become usable again, thereby eliminating the need to remove them and fill landfills with more construction waste.

Pipe lining technology requires no digging or destruction and is an effective, long-term solution for failing pipe systems located both inside and outside of buildings. It can hold up to the structural strength of a new pipe, without the costly digging and replacement repairs.

Pipe liners protect the carried contents from mixing with the metals within the pipes, which can result in decomposition or lead leaching into drinking water. Not only are potable water lines and drain lines being rehabilitated, but the same technologies are used to retrofit vertical applications, roof drains and mechanical systems, including fire suppression and HVAC systems.

Trenchless pipe lining technologies are not new; some of the technologies have been used for decades and have passed the test of time. Since the late 1980s, for example, all of the collection, hold and transfer pipe systems in the U.S. Navy’s aircraft carrier fleet have been lined with Nu Flow’s blown-in epoxy coating.

Established in 1987, American Pipe Lining (APL) began in San Diego, Calif., where it worked with the U.S. Navy to develop and later patent epoxy lining technology to protect aircraft carriers, vessels and piping in government facilities. Equipment was developed to apply an epoxy coating to the interior of pipes in place in order to meet the demands of different applications, conditions and environments. This included maintaining pipes at required temperatures for optimal in-place cleaning and coating.

APL, which was acquired by Nu Flow in 2007, later expanded its lining solutions to include applications in the private and domestic piping markets that faced aging potable water systems and poor water quality. This technology is still being used today and is licensed worldwide to rehabilitate residential, commercial, industrial, federal and municipal properties.

Epoxy coating

Epoxy coating restoration of pipe systems is a non-invasive process; epoxy is used to coat the inside walls of pipes without destruction to the interior or exterior surfaces of building structures, hardscape or landscape. Epoxy coating prevents corrosion and leaks and is regularly used in pipes ½ inches to 12 inches in diameter.

A 40-story, state-of-the-art office space in Lower Manhattan, New York, started experiencing chronic failure and multiple leaks due to corrosion in the black iron heating and cooling system. The system consisted of more than 7,200 feet of 1 ½- to 4-inch diameter black iron heating and cooling pipes.

In order to save millions of dollars in reconstruction and asbestos abatement costs and fix the failing system, blown-in epoxy coatings were used to coat the insides of the pipe walls. This long-term solution to eliminate corrosion and erosion can also be used as a preventative measure.

The epoxy coating process begins with an inspection to determine the problematic areas and pipe dimensions. A plan is implemented to minimize disruption and afford the most efficient timeline for work completion. Spot repairs are made to excessively worn joints and fittings. Temporary bypass water piping may be installed. The system is drained and air-dried. After testing for leaks, the pipes are prepared for cleaning.

Pipes are dried with heated, compressed air and a safe abrading agent is blown through the pipe system, removing rust and corrosion byproducts that are collected in a holding unit for disposal. Compressed air is applied once again to remove fine particles.

Conditioned air uniformly distributes the epoxy throughout the pipe segment. Following the coating application, continuous controlled air flows through the pipe to facilitate epoxy curing. After the epoxy cures, valves and couplings are refitted; a final leak test and inspection confirms the integrity of the line. Water quality, volume and flow tests can confirm the functionality of the system.

Structural lining

Structural lining is another technology used to create a structurally sound pipe within the system without removing the existing pipes. Millions of linear feet of drain and lines have been saved using the pull-in-place structural lining process.

Most facilities built prior to the 1970s have sewer lines composed of cast iron and clay. The most common problem found with these lines is cracking at the joints, root intrusion and the bottom of the pipe rusting out. Other common problems include calcification in sewer lines and ground movement. Root intrusion is reported to cause 50 percent of all sewer blockages. With the structural lining method, roots are removed and a liner is pulled into place.

The structural lining project begins with mapping the internal plumbing system and camera inspection of drain and sewer lines. A plan is implemented to minimize disruption and afford the most efficient timeline for work completion. Depending on the lining method to be used, pipes may be drained and/or air-dried. After testing for leaks, the pipes are prepared for cleaning.

The next step involves removing roots and calcite in order to return the pipe to its original functioning diameter. Removal methods may include jetting the lines or using pneumatic tools, such as a scorpion cutter. Cast iron pipe may require additional preparation if there is significant corrosion or missing sections of pipe.

Existing access points are used to pull an epoxy-saturated felt liner into the host pipe. This lining method provides the ability to line multiple 45- and 90-degree angles, as well as the option of lining specific sections of pipe without lining the entire length. Once complete, a final leak test and camera inspection is performed.

With alternatives to traditional pipe replacement available, it is no wonder that many homeowners, property managers and municipalities are turning to trenchless pipe lining to rehabilitate their pipe systems. This is also why so many plumbing and mechanical companies are adopting pull-in-place structural liners and blown-in epoxy coating technologies and offering them to their clients.