Various rust protection tests are performed on ferrous or steel materials, to provide guidance on a lubricant’s capability to retard rust formation. A common test based on ASTM D665 calls for the immersion of cylindrical steel specimen into a bath with the test-lubricant. Over a period of 4 or 24 hours, seawater is introduced to the bath to accelerate rust formation. The steel specimen should exhibit no rust formation whatsoever after the test, to gain a “pass” rating.
As almost all machinery components contain steel, this test is a very useful guide to the maintenance or lubrication practitioner.
While brushing and spraying are effective means to apply RPO’s, the dipping or bath method is deemed most effective as it endures full coverage on the workpiece. In addition, a dip or bath system provides the thinnest possible effective film on the metal surface, as one can suspend the workpiece for a few seconds after dipping, allowing excess film to drip back to the tank.