Cooling Water Piping Through Wall Leaks

Cooling Water Piping Through Wall Leaks

Market

Power Generation

Challenge

The challenge was to rehabilitate the deteriorated cooling water piping due to through wall leaks.

Cooling water piping at a power plant
Two technicians saturating carbon fiber fabric with resin on a table

Engineered Solution

The solution utilized the HydraWrap® Structural Composite Repair System.

Scope

In 1987, sections of the cooling water pipe were replaced with carbon steel lined with Plastisol (plasticized PVC). Over the years, the liner disbonded from the substrate which subsequently resulted in numerous through wall leaks. These leaks and significant areas of corrosion resulted in poor system reliability and impacted the plant performance. Both the pump inlet and discharge pipe were affected by the deterioration.

A technician working inside a cooling water pipeline, coating the inner walls in epoxy
Epoxy coating the inside of a cooling water pipeline
A technician looking into a cooling water pipeline that has been coated in epoxy

Solution

In order to correct the situation, the plant needed to permanently restore pressure boundary and structural integrity within a normal 22 day maintenance outage, while minimizing the impact on the plant’s capital budget. Direct replacement of the piping was not a practical option due to time and budget constraints. The HydraWrap® carbon fiber system was chosen for its structural capacity, coupled with economical pricing and short installation window.

The project required the removal of the sometimes tenacious existing coatings. Selected pipe spools were removed and other openings were provided to allow access into the piping. The substrate was prepared by grit blasting. The piping system was repaired by applying an epoxy primer, layers of carbon fiber, and a top coat. The entire process was completed in the allotted time frame and was a cost-effective repair option.

Inside view of a cooling water pipeline at a power plant. The interior has been wrapped in HydraWrap to repair the portions that had developed through wall leaks