(source: assesing the future of coating work, PCE 2000)

Anti-corrosion systems for pipelines have been evolving since the early to mid 1900’s. A system has not been developed to date that completely satisfies the end-user. Traditional coating systems are selected from a pool of products that are accepted and specified by most multi-national oil and gas companies worldwide. This pool of products is comprised almost entirely of products that have been in situ for decades. Most coatings, still in use today, date back to the 1960’s.

Asphalt/Coaltar Emulsion

• Used from 1870-1970
• Comprised of a petrolatum based emulsion coating

Advantages
• Easy to apply
• Minimal required surface preparation
• Long track record
• Low costs

Disadvantages
• Subject to oxidation and cracking
• Soil stress failure issues
• Environmental issues
• Exposure issues
• Brittle at low temperatures
• Associated with stress crack failures

Fusion Bonded Epoxies

Used since 1960’s
Comprised of thermosetting thin film powder-coated epoxies, fusion bonded to the pipe

Advantages
• Excellent adhesion
• Ecellent corrosion resistance
• Does not shield corrosion protection
• Low cost

Disadvantages
• Low impact resistance
• High moisture absoption/permeation
• Difficult to field joint
• High thickness to eliminate weld tenting
• Easily damaged during transport
• Complex application process

Two Layer Tape Wrap System

• Used since 1960’s
• Comprises of an impregnated tape that is applied to a rotating pipe

Advantages
• Easy to apply
• Low cost
• Low track record

Disadvantages
• Poor shear stress resistance
• Associated with stress cracking
• Associated with corrosion failures
• Shielding of cathodic protection
• Adhesives subject to biodegradation

Two-layer Extruded Polyethylene systems

Used since 1960’s
Used a exterior sheeting in insulated system when combined with polyurethane foams

Advantages
• Excellent track record
• Good handling features
• Low cost

Disadvantages
• Limited temperature ranges
• Poor shear stress resistance
• Limited applications <24”
• Brittle and shatters at cold temperatures

Three Layer Systems (Tri-lams PPL & PPE)

• Since early 1990’s
• Comprising FBE primer + adhesive layer + PP or PE layer

Advantages
• Excellent track record
• Good handling features
• Excellent combination of features

Disadvantages
• Expensive
• Difficult to field joints
• Complex production process

History of Pipeline Coatings

More photo impressions