Coal Tar Enamel has long been the standard for protecting underground pipelines from the destructive effects of corrosion. Coal Tar Enamel has successfully prevented corrosion to pipelines that have been in the ground for more than 75 years. Today, as a result of Lone Star' continuous improvements in Coal Tar Enamel coatings, pipeline owners can be assured of a lifetime of corrosion protection.

Following are answers to a number of commonly asked questions about Coal Tar Enamel coating systems. We sincerely hope this handout provides enough information for you to consider specifying Coal Tar Enamel for your next pipeline project.

What Is Coal Tar Enamel?
Coal Tar Enamel is a thermoplastic polymeric coating produced from the plasticization of coal tar pitch, coal and distillates, followed by the addition of an inert filler. Pipeline designers and owners have found plasticized Coal Tar Enamel together with primer, fiber glass or mineral felt and outer wrap to be the most efficient and cost effective system for the prevention of corrosion to oil, gas, water, steel and concrete pipelines.

Coal Tar Enamel provides the pipeline with excellent cathodic disbondment protection, good impact resistance, low water absorption, and excellent corrosion protection.

How is Coal Tar Enamel Applied?
Hot Coal Tar Enamel is poured over a rotating pipe that has been previously grit-blasted and primer coated with Reilly Coal Tar Enamel Primer. A fiber glass inner wrap, which becomes saturated with liquefied enamel, is immediately pulled over the coating. A second layer of Coal Tar Enamel is then applied. A second fiber glass or mineral felt outer wrap, already impregnated with coal tar, is applied over the first wrap. Liquid Coal Tar Enamel spreads through the wrap seams. A coating thickness of 2.4 millimeters (3/32 inch) is ideal for life-long protection of the pipeline.

The glass fiber gives the Coal Tar Enamel system additional sheer strength, providing resistance to soil stress, protection against rock damage during back-filling, and improved resistance to sag at elevated temperatures. The coating is then finished with either one coat of white wash or a single wrap of Kraft paper to prevent ultraviolet degradation of the enamel during storage in direct sunlight.