As the paint track moves, the hung parts pass through various specific stages which ensure the final quality of the paint finish:
Stage one – Pre-treatment
The parts undergo a thorough cleaning process to ensure their optimal condition. Initially, a highly alkaline cleaner is applied to effectively remove any manufacturing residue and dirt. Subsequently, the parts are rinsed with both mains water and demineralized water to ensure complete cleansing.
To provide a protective barrier against corrosion, a saline-based liquid pre-treatment known as Oxsilan 9810 is applied. This pre-treatment relies on chemical bonding to enhance the parts’ resistance to corrosion. Following the application of Oxsilan 9810, the parts undergo a final rinse with demineralized water, ensuring the removal of any remaining residue.
By following this meticulous cleaning and pre-treatment process, the parts are prepared to meet the highest standards of quality and durability.
Stage two – drying
After the pre-treatment process, the prepared parts are carefully transferred to an oven set at approximately 180 degrees Celsius. This controlled temperature environment allows the parts to undergo a thorough drying process, ensuring they are fully prepared to receive the epoxy paint powder.
By subjecting the parts to the optimal drying temperature, any remaining moisture is effectively eliminated, promoting excellent adhesion and overall paint finish quality. This crucial step sets the stage for the subsequent application of the epoxy paint powder, ensuring optimal results in the powder coating process.
Stage three – powder application
Once the pre-treated parts are securely mounted on the track, the automated process takes them through the spray booth. Inside the booth, electrostatic spray guns come into action, applying the charged powder to the parts. The electrostatic charge ensures that the powder particles are attracted to and evenly coat the grounded parts, creating a uniform paint layer.
To ensure comprehensive coverage, the parts then proceed to another area where skilled operators equipped with manual electrostatic spray guns meticulously cover any intricate or hard-to-reach areas. This additional step guarantees that all surfaces of the parts receive a consistent and thorough coating of the powder, leaving no areas untouched.
By combining automated and manual application techniques, we achieve a high-quality finish on every part, ensuring complete coverage and a visually appealing appearance.
Stage four – stoving
To complete the powder coating process, the coated parts are conveyed through a gas-fired tunnel oven. The oven is set to a specific temperature depending on the type of powder used. As the parts travel through the oven, they are exposed to the critical temperature at which the powder begins to melt and flow.
During this melting and flowing stage, the powder particles bond together, forming a durable and smooth finish on the parts. The heat of the oven ensures that the powder fully cures, resulting in a resilient coating that adheres securely to the surface of the metal.
Once the parts have gone through the curing process in the tunnel oven, they are fully coated and the paint has reached its final state, ready for use or further processing. This curing step is crucial in achieving a robust, long-lasting finish that enhances the appearance and durability of the parts.