Powder coating including 5-chamber pretreatment and automated shot blasting

Oxsilan® pretreatment benefits:
The Oxsilan® technology is an eco-friendly and by its very nature multi-metal pretreatment process. It is a state-of-the-art alternative to traditional phosphating or chromating processes. All common metals and alloys in any combination can be treated with this thin-film technology. Lightweight materials such as aluminium and high-strength steel can also be pretreated with the Oxsilan® process in the same way as steel and galvanized steel.

Oxsilan® benefits at a glance:
• eco-friendly: lower risk for safety, health and environment
• significantly reduced process costs
• reduced water and energy consumption
• free of nickel and phosphates
• ambient temperature process without heating
• practically sludge-free, reduced maintenance
• fewer process stages, higher productivity
• multi-metal capability
• excellent quality

Working principles of Oxsilan®:
The base materials for the Oxsilan® technology are silanes. During the manufacturing process the silanes are hydrolyzed and converted to polysiloxanes. During the coating process the reactive silanol groups are chemically bonded to the metal surface as well as to the paint coating. Heat treatment following powder coating further cross-links the polysiloxanes creating layers in the range of 100 nm. In combination this is already sufficient to achieve the same degree of corrosion protection as with ten times thicker zinc-phosphating layers thereby reducing material consumption and pre-treatment times and increasing productivity: improvements of 30% and 65% can be realized in practical applications.

Automated shot blasting:
We use the Rösler Overhead-Rail-Blast-Cleaning-Machine RHBE 17/22-L, which provides excellent surface pre-treatment for steel. It enables to achieve the best possible adhesion in coating process. The machine has variable speed control unit turbines that also enable to clean parts and assemblies from thinner materials. The rotating and an oscillation of the hook during the blasting cycle guarantees an uniform coverage and the installed frequency inverter ensures smooth oscillation of the hanged parts.

Water drying and powder curing oven:
The oven is divided into two separate sections – it is designed for both water drying of parts leaving the pretreatment plant and for powder paint curing after powder application. The heating of drying section is supported by using heat beaming from the uninsulated wall dividing curing side from the drying. Further all oven exhaust air leaves through the drying section before leaving the oven system to heat exchange the hot air into the process before exhaustion. This combined principle gives the optimal energy transfer efficiency and minimizes the heat loss from the oven system.