Investigate the root cause of defect with help of various tests & international standards. Suggest suitable solutions to the problem.

Coating Condition Survey and Failure Analysis

A systematic evaluation of protective coatings applied to structures, equipment, or surfaces. It helps assess the condition of coatings, identify causes of failure, and recommend corrective actions to extend asset lifespan and improve performance.

1. Coating Condition Survey

A coating condition survey is performed to evaluate the state of protective coatings and determine maintenance needs.

Key Steps in a Coating Condition Survey

1. Visual Inspection

   • Identify discoloration, chalking, blistering, cracking, peeling, or other visible defects.

   • Check for corrosion or substrate exposure.

   • Assess the general adhesion and integrity of the coating.

2. Surface Preparation & Application Review

   • Verify if the coating was applied according to specifications.

   • Evaluate the cleanliness and roughness of the substrate.

   • Identify issues with coating thickness, coverage, or improper curing.

3. Adhesion Testing

   • Pull-off (dolly) adhesion tests.

   • Cross-cut or knife adhesion tests.

4. Dry Film Thickness (DFT) Measurement

   • Use non-destructive methods like magnetic or ultrasonic gauges.

   • Compare against the original coating specifications.

5. Environmental Exposure Assessment

   • Consider environmental conditions like UV exposure, humidity, and chemical exposure.

   • Identify areas of accelerated degradation due to aggressive environments.

6. Documentation and Reporting

   • Record findings with photos and notes.

   • Rate coating conditions based on industry standards (e.g., SSPC, NACE, ISO).

   • Recommend maintenance or re-coating strategies.

2. Coating Failure Analysis

When coatings deteriorate prematurely, failure analysis helps determine the root cause.

Common Causes of Coating Failures

1. Improper Surface Preparation

   • Inadequate cleaning (presence of oil, rust, or contaminants).

   • Incorrect surface profile (too smooth or too rough).

2. Application Defects

   • Insufficient or excessive coating thickness.

   • Inconsistent mixing, thinning, or curing issues.

   • Poor environmental conditions during application (temperature, humidity, dust).

3. Substrate-Related Issues

   • Corrosion under the coating (undetected before application).

   • Surface defects like pitting or cracks affecting adhesion.

4. Chemical and Environmental Degradation

   • UV degradation leading to chalking and color fading.

   • Chemical attack causing softening or blistering.

   • High humidity or immersion leading to osmosis and delamination.

5. Mechanical Damage

   • Impact, abrasion, or flexing stress on the coating.

   • Expansion and contraction causing cracking.
     
     
     

3. Corrective and Preventive Actions

1. Surface Preparation Improvements

   • Follow industry standards (SSPC-SP10/NACE No. 2 for near-white metal blast cleaning).

   • Remove contaminants and ensure proper surface profile.

2. Application Best Practices

   • Use correct coating type and thickness.

   • Control environmental conditions during application.

3. Material Selection

   • Choose coatings suitable for the service environment.

   • Use high-performance coatings for extreme conditions (e.g., epoxy, polyurethane).

4. Regular Inspections and Maintenance

   • Establish routine coating condition assessments.

   • Implement touch-ups and recoating schedules as needed.