Gilsonite in Pipe Coating: An Overview

Buried steel pipelines carrying water, oil and gas must be protected from corrosion for decades. Bituminous coatings — including those modified with gilsonite — have a long record in this field.

Why pipes corrode

Moisture, oxygen and soil salts attack bare steel. Coatings act as a barrier and work with cathodic protection.

Role of gilsonite

• Raises hardness and softening point of bituminous enamels
• Improves adhesion to steel
• Reduces cold flow and sagging
• Increases resistance to soil stress

Coating types

• Hot-applied bitumen enamels
• Cold-applied primers and mastics
• Coating tapes with bituminous adhesive

Main bituminous pipe coating systems

Why gilsonite is added

Pipe coatings must resist soil stress (movement of soil around the pipe), impact during laying and flow at elevated service temperatures. Gilsonite raises softening point and hardness while keeping adhesion to steel.

Where bituminous systems are used today

Many new oil and gas pipelines use polyethylene or epoxy systems, but bituminous coatings remain common for water pipelines, rehabilitation, field joints and repairs because they are economical and forgiving to apply.

See pipe coating grade gilsonite and bitumen enamel pipe coating.