Internal Rehabilitation of Heat Exchanger Using Belzona 1111 & 1321

KHIA ID: 9923
Industry: Heating, Ventilation & Air Conditioning (HVAC)
Application: HEX-Heat Exchangers (HEX)
Substrate: Carbon steel
Customer Location: 2900 Veterans Way, Melbourne, FL 32940
Application Date: July 2025
Products: Belzona 1111 (Super Metal),Belzona 1321 (Ceramic S-Metal),Belzona 9111 (Cleaner Degreaser)
Problem: The customer was experiencing severe internal corrosion in the heat exchanger’s tube sheets, covers, and water box. Oxidation had caused metal loss, flaking, and surface degradation, threatening the unit’s structural integrity and performance. There was concern about potential leakage and the high cost of replacement.
Corroded heat exchanger tube sheet with visible rust and metal loss prior to surface preparation.

Initial condition of the heat exchanger showing severe corrosion and rust accumulation on the tube sheet surface.

Blasted heat exchanger tube sheet with corks inserted in each tube and a uniform surface profile.

Surface after abrasive blasting, showing a clean and profiled tube sheet ready for application. Tubes protected using corks.

Tube sheet undergoing repair with Belzona 1111 applied over blasted surface, masking in place.

Rebuilding damaged areas using Belzona 1111 (Super Metal) to restore metal loss and ensure structural integrity.

Final view of heat exchanger tube sheet coated with Belzona 1321; all plugs removed, showing clean and restored surface.

Completed application of Belzona 1321 in two coats with plugs removed, revealing a smooth and fully protected tube sheet surface.

Application Situation
The customer was evaluating a costly replacement of a corroded heat exchanger. By selecting the Belzona solution, they avoided extended downtime and significant capital expenditure. The application was performed on-site with minimal disruption to adjacent systems, restoring structural integrity and providing long-term corrosion protection at a fraction of the cost of replacement.
Application Method
The internal surfaces were abrasive blasted to obtain a clean and rough surface with an anchor profile of approximately 3 mils. A chloride contamination test was performed after blasting to confirm surface suitability. Degreasing was then carried out using Belzona 9111. Areas with visible metal loss or damage were rebuilt using Belzona 1111 (Super Metal). After the rebuilding process, Belzona 1321 (Ceramic S-Metal) was applied in two coats, grey followed by blue, to ensure full coverage and long-term corrosion protection.
Belzona Facts
By choosing Belzona, the customer avoided the high cost and extended lead time associated with full equipment replacement. Belzona offered an in-situ repair solution with minimal disruption, reduced downtime, and extended service life. The combination of Belzona 1111 and 1321 provided structural rebuilding and long-term protection, making it a cost-effective and technically superior alternative to welding or replacement. Additionally, the visual color contrast between coats ensured proper application and quality control.
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