The National Oil Seal Interchange is a method or chart that enables a user to match an oil seal made by National Seals with an equivalent or substitute made by another company. It is a method of matching one manufacturer’s part with that of another manufacturer.
Oil seals, also called grease seals, fluid seals or dirt seals, close the spaces between stationary and moving components in mechanical equipment and help prevent lubricant from escaping. They also prevent abrasive particles and corrosive or otherwise harmful contaminants from mixing with the lubricant or other fluids and entering the machinery.
Oil seals are vital components of practically every type of automobile, vehicle and machine in operation, and protect all types of precision-crafted equipment, such as close-fitting ball, sleeve and roller bearings. Their primary application is in automobiles and industrial machinery.