If you follow us often, you will know that we are constantly mentioning that at Yadan Steel Furniture, we stick our core values on environmental protection and sustainability. So on what grounds do we have the audacity to assert that our products are environmentally friendly and healthy? The answer lies in the processing procedures. One of our key processes is the electrostatic powder spraying for coating. Today we will talk to you about this process.
What is powder coating?
Powder coating is a type of surface treating technique that involves the application of a dry, solvent free finely ground powder to a surface, which is then heated to fuse the powder particles together and form a smooth, durable finish.
The powder is made by mixing special resin, pigments and fillers, curing agent and other additives in a certain proportion, and then going through hot extrusion and powder sieving. After being stored and stabilized at room temperature, it is sprayed electrostatically or dipped in a fluidized bed, then heated and baked to melt and solidify to form a smooth and bright permanent coating film, which can achieve decoration and anti-corrosion purposes.
How we do powder coating at Yadan Steel Furniture
This illustration in motion says clearly about the powder coating process when we process steel furniture at Yadan. We can see that in our workshop, we have an interlocking, strictly executed production line divided into many steps. After shearing, extruding and deforming the steel plate on the shape, we started to work on its surface.
We put steel panels in this long tank (at around 0:13) to remove impurities that may interfere with the coating's adhesion to the surface, and then add silane coupling agents to make the coating more tightly bonded. Various washing and rinsing cycles are applied throughout the process to remove remaining cleaning agents or other residues.
When all the conditions are set, we can do the powder coating process. Steel panels are suspended on an overhead conveyor line (at around 0:24), and an electrostatic spraying machine is used to spray a dry powder material on the surface of the panels. By electrostatic interaction, the powder will be evenly adsorbed on the surface to form a powdery layer. This powdery layer is then baked, leveled and cured at high temperature, and becomes the final coating with a range of good properties.
The difference between powder spraying and traditional painting
Advantages of powder coating:
1. Powder coating does not contain solvents or volatile toxic substances, which is beneficial to the occupational health of workers at the production process, and also harmless to the environment and human body as a finished product.
2. The material utilization rate is high, with the excessive powder sprayed subject to recycling. The overall utilization rate during powder coating process is over 95%.
3. It also has excellent anti-corrosion properties, as this technique will form a hard, protective layer highly resistant to moisture, chemicals, and other environmental factors that can cause corrosion over time.
4. The powder coating process also has aesthetic advantages. It allows for a thicker, fuller coating layer and more even application of color. It also has a wide range of colors and textures of finishes for choice, with a variety of vibrant and lively colors, and glossy, matte or metallic styled surface qualities.
It entails the use of a large amount of organic solvent-based paint, which will cause pollution and public hazards due to volatilization. It also has a strong odor, and is prone to causing poisoning incidents and fires.
Conclusions from the comparison:
Therefore, compared with traditional solvent-based coatings, powder coating has the advantages of safer, less pollution, good adaptability, high efficiency and no dependence on petroleum as raw material.
This video explains it in a more intuitive way.
Attached: the formaldehyde-free test report for Yadan Steel Furniture's products
It shows that at normal temperature, in a detection space of 5 cubic meters with an air exchange rate of 1.2 times per hour, formaldehyde and volatile organic compounds such as xylene, toluene, and benzene cannot be detected at a measurement level of milligrams per square meter.
This is a test we invited professional organization SGS-CSTC Standards Technical Services Co., Ltd to do. The body is a joint venture between Swiss SGS SA (Société Générale de Surveillance) and Chinese state-owned China Standard Technology Development Corp, both very authoritative organizations in inspection, verification, testing, and certification services.