Powder coating systems are extremely cost efficient, offering durability and good corrosion resistance with exceptional levels of appearance and finish. The main difference between conventional paint and powder coating is that in wet painting, solids are in a suspension liquid which must evaporate before a solid coat is produced. In powder coating a thermoplastic or thermoset polymer creates a hard finish that is tougher than conventional paint. So, how does our ‘best practice’ system obtain the best quality finish from pre-treatment to transportation?
- Pre-treatment
- For galvanised steel, components are fully fettled with the use of a soft pad grinding disc that removes all spikes and drips of excess zinc. This operation also scores the surface of the zinc coating, by doing so it forms a key for the powder that improves the thickness and adhesion of the finished powder coating. Components are air cleaned to remove residue from the grinding operation. A T Wash solution is applied to promote good adhesion
- For black steel, components are degreased and shot blast
- Components are degassed in an oven to remove dissolved gases and avoid potential bubbling
- Powder is applied using an electrostatic spray gun to achieve the manufacturer’s recommended coating thickness, over the entire component. Powder coated items produce much thicker, even coatings than conventional liquid coatings without running or sagging.
- Goods are cured in an oven in line with paint manufacturers specification and best work practices
- Quality inspection
- Paint thickness testing
- Paint adhesion test carried out to ISO 4624:2002