Rehabilitation of sweating Gas Pipeline

     Performing pipeline coating applications to in-service gas pipelines has been a difficult task for many years. Pipeline operators and contractors have struggled trying to find an effective coating that can be successfully applied to pipe that condensates throughout the year. And, the coating needs to provide outstanding adhesion and resistance to cathodic disbondment. Pipe condensation occurs when the operating pipe temperature during excavation, remains lower than the ambient dewpoint temperature. Pre-heating the surface is not an option when a gas pipeline is in service, therefore a moisture tolerant coating is the only option.

    In the Spring of 2023, a major pipeline company selected Denso’s Protal 7300 liquid epoxy to be used to rehabilitate approximately 600 LF of 24″ pipeline near Freeport, TX.  Gulf Coast Pipeline Services effectively applied the Protal 7300 utilizing Protal Applicator Pads and 4″ brushes to the wet surface at approx. 30 to 50 mils DFT. With the pipe temperature running at 60°F, the coating was fully cured in approx. 6 hours and backfill was able to be done later in the day or early the next day throughout the project.

    At the completion of the project, both the Operator and Contractor were very pleased with the application, appearance and performance of the Protal 7300. Furthermore, they were confident that they now had the product of choice for any future projects with similar conditions.