GMKOREA EDS-T-7019 PDF

The organic coating is applied by barrel processing or racking over properly zinc phosphated small parts. Parts from either process are oven cured at 200 for a minimum of 18 minutes. Immediately following the cure, the parts are immersed in a corporation approved protective oil compound in concentrations, temperatures and immersion times specified by the approved chemical manufacturer.

PURPOSE

This specification covers basic requirements for a black corrosion protective coating which is protective coating which is produced in a process consisting of zinc phosphate treatment, chromic acid rinse or seal, organic coating, oven bake, water and oil emulsion post treatment and air dry.

This coating is especially suitable for bolts, clips and other small ferrous parts where above normal levels of corrosion protection, freedom from hydrogen embrittlement and decorative black color are desired.

Parts that are not suitable for barrel processing may be racked but must be processed through the same black organic coating employed in the barrel process.