The choice of pipeline anticorrosive paint?
The surface treatment of aluminum alloy die castings is divided into pre-treatment and post-treatment.
Pre-treatment is to remove surface oxide scale and oil stains, increase post-treatment adhesion and improve appearance.
The most commonly used surface treatments for aluminum alloy die castings are shot blasting, sand blasting and phosphating.
Post-treatments generally use 4 types of spraying, oxidation, electroplating, and electrophoresis.
Other surface treatment methods are only used for products with special requirements due to cost reasons.
From the cost aspect, the pre-treatment is shot blasting → sandblasting → phosphating → polishing,
spraying → electrophoresis → oxidation → electroplating.
After phosphating, only spraying and electrophoresis can be carried out, and oxidation and electroplating treatments are not allowed.
Choose from decoration and anti-corrosion,
and the pre-treatments are polishing → phosphating → sandblasting → shot blasting,
oxidation → electroplating → spraying → electrophoresis.
Surface pretreatment methods
There are many oxidation methods.
Before surface treatment of aluminum tubes, different oxidation treatment processes should be selected according to their own requirements:
1. Anodizing-produce a dense aluminum oxide film on the surface of the aluminum tube to make it react with air again to improve the protective performance of the aluminum tube. At the same time, the oxide film isolates the free ions inside, making it impossible to conduct electricity.
2. Coloring after anodizing-various colors are formed on the oxide film to meet certain usage requirements, such as black for optical instrument parts and golden yellow for medallions.
3. Chemical oxidation-used for general protection, the processing technology is generally difficult, and the production cost is low.
4. Apply organic protective layer (organic paint such as paint)-used for external protection and decoration of equipment, usually on the basis of oxidation.
The aluminum alloy tube itself has good corrosion resistance, and after anti-oxidation treatment, it is more difficult to rust.
This is why aluminum alloy pipes are more durable than ordinary carbon steel pipes and galvanized pipes.