Aluminium fins for heat exchangers are mainly pre coated with blue or gold color hydrophilic coating for better cooling effect. Technical Specifications of hydrophilic aluminum fins for heat exchangers in air conditioner are listed by Haomei Aluminum:
- Foil Shape:
Firstly, the production process of coated aluminium fins for heat exchangers requires that the foil has good plate shape, which is a prerequisite for the production of coated aluminum foil fins. The unit for measuring plate shape is I. The general requirement for plate shape by coating production equipment is within 20-40I. If it exceeds this value, a tension leveling system needs to be added before the coating equipment. Generally, the aluminum strip route for coating equipment is longer, with more processing steps and guide rollers. Therefore, if a tension leveling system is not equipped, it is easy to cause folding during operation, resulting in production failure.
Secondly, the production process of air conditioners also has high requirements for the plate shape of aluminum fins for heat exchangers. Generally, vacuum suction cups are used for aluminum foil transportation in the production line of heat exchanger fins. If the plate shape of the aluminum foil is not good and the surface is not smooth, the vacuum suction of the aluminum foil cannot be performed properly.
- Coating Thickness:
There is no strict requirement for the coating thickness on the surface of the aluminum foil fin stock, generally within 3/1m. Since the price of coatings is generally expensive, the thinner the coating thickness is controlled while meeting the performance requirements, the lower the production cost will be. The coating thickness directly affects various performance indicators of the coating, so the coating thickness on the surface of the aluminum foil fins should be evenly consistent.
- Coating Adhesion:
Coating adhesion is an indicator of the bonding strength between the aluminum foil and its surface coating. If the coating adhesion is too small, the surface coating of the coated aluminum foil will easily peel off during further processing and use, seriously affecting the weight of the coated aluminum foil fins. Therefore, a stronger coating adhesion is required. Coating adhesion can only be qualitatively tested, and the main detection methods include abrasion resistance test, grid cut test, and cupping test.
- Hydrophilic Performance:
After a period of use, the hydrophilic performance of hydrophilic aluminium fins for heat exchangers is affected by various environmental factors. Therefore, the hydrophilic performance is generally divided into initial hydrophilicity and hydrophilic performance after environmental test. The quality of hydrophilic performance is determined by the angle formed when water adheres to the surface of the aluminum foil. The requirement for initial hydrophilicity of the aluminum fins for heat exchangers product is normally a<100, and the requirement for hydrophilic performance after environmental test is a<250.
- 5. Corrosion Resistance:
The corrosion resistance is mainly reflected in three aspects.