Coil Options > Coatings
Cleanable l Performance Enhancements l Casings l Coatings
There are many protective coatings on the market that can extend the service life of a heat exchanger. Also, there are methods to polish a coil to make it aesthetically pleasing and easy to clean. Each has certain qualities and limitations, but no one coating is good for every environment. In order to select the best protective coating for your application, please provide detailed information regarding the environment in which you plan to use your coil such as:
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Operating Temperature
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Potential for Condensation
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Type of Gas being used
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Components present in the air
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Liquid being used
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Other Materials and/or Coatings being used in the same equipment
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Durability of other materials used in the system
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Frequency of cleaning the coil, the cleaning agent and method used
Also see our Corrosion Resistance Guide in the Resources and Technical section for the durability of materials to certain chemicals and environments.
Most common types of coatings
Acrylic
A coating for aluminum fins that is resistant to organic and inorganic acids (less than 10% concentration), alkalis, salts (less than 20% concentration) and many solvents. This coating is particularly good in acidic, caustic environments (food acids).
Baked Phenolic (Heresite)
Offers good to excellent resistance to a wide range of chemicals and solvents. The dipping process encapsulates the coil in the coating before it is heat cured. A coil is typically dipped a minimum of two times.
Epoxy (Electrofin)
Offers consistent film uniformity and coverage especially on edges and bimetallic joints. It is this consistency that improves corrosion resistance to perform within a 3.0 to 12.0 pH range. It provides outstanding flexibility and durability and excellent chemical and corrosion protection.
Epoxy Powder Coating
This is mainly used as an aesthetic coating for steel, copper, galvanized steel and aluminum, and comes in different colors. This coating does provide some corrosion resistance, depending on the brand being used.
Hot Dip Galvanizing
A superior industrial coating providing long-term corrosion protection of steel. This zinc coating offers dual protection:
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Coating metallurgically bonds to steel providing barrier protection.
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Sacrifices itself to protect the underlying steel.
Nickel Plate
Nickel plating can be applied by an electrostatic (does not guarantee uniformity throughout the coil), or electro-less (guarantees uniformity) process. It is resistant to acids, alkalis, salts, seawater and chlorides. The plating has a bright, shiny appearance and is more wear resistant than tin plating.
Electro-Tin Plated
Soft, but very ductile. This coating has a high luster and smooth surface when fused. Corrosion resistance is good and solderability is excellent. The coating can be applied directly to copper or nickel surfaces or to clean steel or brass after being treated with a barrier film of copper or nickel.
Polyurethane
Primarily used in exterior applications. It has excellent exterior durability, flexibility and elongation, with good chemical and corrosion protection. Most types are easily field repairable.
Iridite
A chemical conversion process of the metal surface that is intended to provide corrosion prevention when left unpainted, and improve adhesion of paint and finishes to aluminum and aluminum alloys.
Lacquer
A very durable coating, excellent for dip applications. It has a fast cure time and is good for interior and exterior use. Several kinds of lacquer are USDA approved.
Pre-Coated Fins
In special cases, Super Radiator Coils can produce coils with pre-coated fin stock. Generally, coated fin stock is corrosion resistant (salt spray) and decorative. Types of coated fin stock include silicone polyester, tin, and hydrophilic.
Coil Surface Polishing
Electropolish
This electro-chemical process brings the chromium in stainless steel to the surface and smoothes it to a bright, mirror-like finish. The result improves corrosion resistance, reduces adhesion of debris and provides a decorative look. Unlike nickel or tin plating that coats the surface, the electropolishing treatment is permanent.
There are other coatings available, and we are willing to investigate special coatings for your particular process. Please contact the closest Super Radiator Coils facility to discuss.