Hot-Applied Bitumen Enamel Pipe Coatings

Hot-applied bitumen enamel is one of the oldest pipeline coating systems and is still used for water pipelines and in some regions for oil and gas.

System layers

1. Surface preparation (blast cleaning)
2. Primer
3. Hot enamel
4. Reinforcement (glass fibre)
5. Outer wrap

Gilsonite’s contribution

Gilsonite hardens the enamel, increasing softening point and reducing penetration so the coating resists soil stress and handling damage.

Typical properties targeted

• Softening point above 100°C for many enamels
• Low penetration
• Good flexibility at installation temperature

Application sequence

1. Blast cleaning to the specified cleanliness and roughness.
2. Priming with a compatible bituminous primer.
3. Hot enamel applied at controlled temperature.
4. Inner wrap of glass fibre embedded in the enamel.
5. Second enamel layer and outer wrap for mechanical protection.

Process control

Testing

Holiday detection with a spark tester, thickness measurement and peel adhesion tests confirm quality.

See pipe coating grade gilsonite.