Overview
ISO 18797-2:2021 specifies selection criteria and minimum requirements for maintenance and field-repair protective coating systems for riser pipes exposed to splash-zone conditions in the petroleum, petrochemical and natural gas industries. The standard covers field-applied coatings used to repair or maintain existing riser coatings, defines qualification and inspection expectations, and describes test programs and coating types suited for offshore and nearshore riser corrosion protection. It does not cover techniques to restore structural integrity of risers or additional mechanical protection materials. New shop-applied riser coatings are addressed in ISO 18797-1.
Key Technical Topics and Requirements
- Scope and applicability: Field repair and maintenance of external riser coatings in splash-zone environments.
- Coating types: Detailed guidance for common field systems such as non-crystalline low-viscosity polyolefin coatings, petrolatum/wax tape wrap systems, and polychloroprene-based elastomeric coatings.
- Selection criteria: Factors influencing coating choice including substrate wetness, soluble-salt contamination, dust and oil contamination, compatibility with existing coatings, access/space and time constraints, and environmental conditions (temperature, humidity).
- Qualification and procedures: Requirements for documented application and inspection procedures (APS and ITP), procedure qualification trials, pre-production trials, and production testing.
- Inspection, testing and traceability: Mandatory inspection documentation and traceability, with test programs covering thickness measurement, holiday detection, adhesion, cathodic disbondment resistance, impact and indentation resistance, ageing/weathering and hot-water immersion behavior, electrical insulation properties, and layer peel/overlap integrity.
- Operational performance: Guidance on mechanical load resistance, interaction with cathodic protection systems, and long-term resistance to weathering and water exposure.
Practical Applications and Users
ISO 18797-2 is intended for:
- Offshore and onshore asset integrity engineers planning riser pipe maintenance and splash-zone corrosion protection.
- Coating manufacturers and suppliers developing field repair coatings and systems.
- Maintenance and repair contractors executing in-situ coating repairs.
- Inspection, QA/QC and testing laboratories qualifying repair methods and producing inspection/test plans.
- Operators and engineering consultants creating procurement specifications and acceptance criteria for riser repair work.
Use cases include emergency patch repairs, scheduled maintenance of riser coatings, retrofits where existing coatings need compatible field repairs, and qualification of contractor application methods.
Related Standards
- ISO 18797-1 - New construction shop-applied riser coatings (compatible maintenance and repair systems in ISO 18797-1 are referenced by this part).
Keywords: ISO 18797-2, riser pipe coating, splash zone corrosion protection, maintenance and field repair coatings, petroleum petrochemical natural gas, coating qualification, cathodic disbondment, petrolatum tape wrap.