Denso says pipeline owners and contractors need to pay closer attention to how pipe coatings are protected before assets enter service.
The corrosion prevention and sealing technology company said many long-term integrity issues can begin during installation, particularly on horizontal directional drilling, boring, slip lining and other trenchless projects.
In those applications, coated pipe can travel through confined paths under sustained friction, directional stress and contact with irregular ground conditions.
Denso said the issue is not only whether pipe coatings can resist corrosion once buried.
It is whether the coating system can survive installation intact.
Why does HDD change coating risk?
Traditional open-cut installation exposes pipe to handling, lowering-in and backfill risks.
Those risks can be significant, but they are often visible and easier to manage during construction.
Horizontal directional drilling changes the risk profile.
During an HDD pullback, the pipe may move through a bore over long distances while the coating is exposed to friction, side loading, and repeated contact with rock or protrusions.
Denso said that such exposure can create localised gouges, impact damage, or thinning that may not be obvious during installation.
If the primary coating is compromised, the asset can enter service with a higher risk of future corrosion.
That can increase reliance on cathodic protection and create greater pressure for inspection and maintenance over the asset’s life.
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Why is abrasion only part of the problem?
Denso said project teams can underestimate the issue when they focus only on abrasion resistance.
Abrasion is important, but trenchless installations can expose coatings to a broader set of mechanical forces.
The company points to shear, abrasion, impact and gouge, sometimes grouped as SAIG, as a more complete way to think about installation damage.
Shear can affect seams, overlaps and transition areas.
Abrasion comes from repeated sliding contact.
Impact occurs when sudden, localised forces act on the pipe surface.
Gouge damage can occur when sharp objects or concentrated pressure cut deeper into the protective layer.
For pipeline engineers and specifiers, that means a coating system that performs well in one abrasion test may not provide enough protection during a demanding bore.
How can outerwraps protect pipe coatings?
Denso said many project teams are moving toward a layered protection approach.
In this model, the anti-corrosion coating remains the primary barrier.
A separate mechanical layer is added where installation conditions justify extra protection.
That outer layer acts as a sacrificial barrier during construction.
Its role is to absorb scraping, dragging, impact and point-load damage so the corrosion-control coating underneath remains intact.
Denso said this approach is particularly relevant for long HDD crossings, mixed geology, urban utility corridors, environmentally sensitive routes and rehabilitation projects inside existing infrastructure.
These are the settings where retrieval would be difficult, delays would be costly or underground conditions remain uncertain.
Where does Bore-Wrap fit?
Denso has positioned Bore-Wrap as a field-applied, abrasion-resistant outer wrap for HDD, boring, and other mechanically aggressive installations.
The company said the product is designed to protect approved coating systems, including fusion-bonded epoxy, shrink sleeves, liquid epoxies, three-layer polyethylene and three-layer polypropylene.
Bore-Wrap uses a fibreglass-reinforced, moisture-cured urethane composite structure to form a hardened sacrificial laminate over the primary coating.
Denso said its performance focus includes resistance to impact, gouge, abrasion and fracture.
The company also points to rapid curing and a broad application temperature range as practical features for construction crews working under changing weather and schedule pressure.
Why does installation practicality matter?
Denso said field practicality can be as important as laboratory performance.
Products that are difficult to install consistently, slow to cure or highly sensitive to weather can introduce new risks on site.
That makes working time, curing behaviour, crew repeatability and contractor training important parts of coating protection.
For water and wastewater pipeline projects, these details matter because assets are often installed in constrained corridors, road reserves, river crossings and environmentally sensitive areas.
Where access after installation is limited, preventing coating damage during construction can be cheaper than finding and managing defects later.
What does this mean for water infrastructure projects?
The water industry is using trenchless methods to reduce surface disruption, manage difficult crossings and work around existing assets.
That creates clear benefits for communities and project delivery.
It also means pipe coatings are being asked to perform through more demanding installation conditions.
Denso said the better approach is to assess protection needs from the start of the design process.
That means considering route conditions, soil and rock risk, pull length, installation method, coating compatibility and the cost of recovery if damage occurs.
For utilities, engineers and contractors, the message is that pipeline coating protection should not be treated as a late construction detail. It should be part of lifecycle risk management before the pipe is buried.
