Sometimes the most impressive projects start with seemingly impossible challenges. When we arrived at a 50-year-old power plant condenser repair site in South America, we found a 50 megawatt steam condenser with 42% of its tubes permanently plugged.
Most would have recommended complete replacement. We saw an opportunity for comprehensive rehabilitation.
The Challenge: A Severely Compromised Condenser System
The situation was complex and demanding:
- 42% of the 4,800-tube bundle was plugged – an unusually high number that severely limited capacity
- Severe inlet end erosion had damaged hundreds of additional tubes
- Extensive corrosion across the tube sheet created integrity concerns
- Circulating water leaks compromised steam purity and shell side performance
- Known boiler integrity issues compounded the condenser problems
- Poor turbine back pressure reduced overall plant efficiency
The plant needed to recover lost condenser surface area while extending the unit’s operational life by at least five years.
Our Comprehensive Rehabilitation Strategy
After consultation with plant engineers, we focused our efforts on one of the two bundles in the divided condenser. Our approach integrated multiple specialized services:
Phase 1: Complete Assessment and Tube Recovery
We began by removing all existing tube plugs and individually assessing each previously plugged tube:
- Marked each tube for either repair or permanent re-plugging
- Identified several hundred completely severed tubes from erosion wear
- Found over 1,000 tubes suitable for restoration to service
- Permanently plugged only the tubes deemed non-repairable
Phase 2: Advanced Surface Preparation
Every tube marked for repair, plus all existing in-service tubes, received our specialized tube ID grit blasting treatment:
- Complete removal of cooling water scale and deposits
- Thorough preparation for coating application
- Uniform surface conditioning across the entire bundle
Phase 3: Protective Coating Application
We applied our proprietary thin film protective coating system:
- Hydrophobic coating for heat exchangers applied to full-length tube IDs
- Single application process covering approximately 80% of the bundle
- 100% solids epoxy system formulated for superior capillarity
- Non-reactive interface that prevents future fouling
Phase 4: Comprehensive Tube Sheet Protection
Our industrial tube sheet coating system provides multi-layer protection:
- Flowable prime coat to wet-in and seal tube and tube sheet joints
- High-build paste grade polymer epoxy for structural protection
- Total application thickness of 1,200 microns across the tube sheet
- Protective inert barrier against galvanic potential
Impressive Results: Performance Recovery and Life Extension
The comprehensive condenser bundle restoration delivered measurable, significant improvements:
Surface Area Recovery
- More than 1,000 previously plugged tubes returned to circulating water service
- 20% increase in operating surface area of the 4,800-tube bundle
- Dramatic improvement in heat transfer capacity
Performance Enhancements
The restored condenser delivered immediate operational benefits:
- Improved turbine back pressure from increased condenser efficiency
- Enhanced plant heat rate due to better heat transfer performance
- Successful shell side hydro test confirmed complete operational integrity
- Five-year life extension achieved for the 50-year-old equipment
Long-Term Protection Benefits
Our hydrophobic thin film coating provides ongoing advantages:
- Eliminates cooling water fouling and scale attachment completely
- Prevents further erosion at the substrate level
- Reduces inlet-end friction and cooling water velocity erosion
- Eliminates formation of under-deposit corrosion cells
The Science Behind Our Coating Technology
Our Curran thin film coating system offers several technical advantages:
Advanced Material Properties
- 100% solids epoxy formulation for maximum protection
- Superior capillarity ensures complete coverage
- Homogenous curing system creates uniform protective barrier
- Hydrophobic properties actively repel water and deposits
Application Versatility
- Flowable blends for complex geometries and tight spaces
- Paste grade, high-build formulations for structural applications
- Single-system compatibility across multiple application types
Key Project Success Factors
Integrated Service Approach
Rather than managing separate contractors for cleaning, inspection, and repair, the plant worked with our complete team throughout the project. This eliminated communication gaps and ensured consistent quality standards.
Comprehensive Problem-Solving
We addressed not just the obvious tube plugging issues, but also:
- Preventive measures against future erosion
- Long-term fouling prevention through hydrophobic coatings
- Structural protection of the tube sheet system
- Predictive maintenance planning for ongoing performance
Proven Expertise
Our decades of experience in power plant condenser repair and specialized coating technologies enabled us to tackle this complex rehabilitation successfully.
What This Means for Plant Operations
This project demonstrates several important principles for condenser tube cleaning and restoration:
Economic Benefits
- Avoided complete condenser replacement costs
- Extended equipment life significantly beyond original expectations
- Improved plant efficiency through better heat transfer
- Reduced maintenance requirements through protective coatings
Operational Improvements
- 20% increase in condenser capacity from restored tubes
- Better turbine performance from improved back pressure
- Enhanced steam purity from eliminated leaks
- More predictable maintenance scheduling
Long-Term Value
The hydrophobic coating continues protecting against:
- Scale formation and fouling
- Erosion and corrosion damage
- Under-deposit corrosion cells
- Future tube plugging requirements
Why This Project Represents “Another Day” for Us
While recovering over 1,000 tubes and achieving 20% surface area improvement might seem extraordinary, this type of comprehensive rehabilitation represents our standard approach to heat exchanger coating and restoration challenges.
Our integrated teams regularly tackle complex projects that combine:
- Advanced condenser tube cleaning techniques
- Specialized NDE inspection services
- Proprietary coating applications
- Long-term performance optimization
Ready to Explore Your Condenser Rehabilitation Options?
If your facility is dealing with excessive tube plugging, reduced condenser efficiency, or aging heat exchanger equipment, comprehensive assessment and rehabilitation might offer better value than replacement.
Contact us at (281) 339-9993 or dgrimes@curranintl.com to discuss your specific challenges. Our team can evaluate your equipment condition and develop a customized restoration plan that maximizes performance recovery while extending operational life.
Visit our website to learn more about our complete heat exchanger cleaning services, inspection capabilities, and specialized coating solutions.
This case study represents actual project results from our comprehensive condenser rehabilitation work. Every project is unique, but our integrated approach consistently delivers measurable improvements in performance and equipment longevity.