TABLE OF CONTENTS To filter means to to take out. As we have read in earlier chapters, lubricants are made up of base stock oils and lubricant additives blended together; another ingredient we can be certain existing in new lubricant is dirt, or contamination. Inevitably, airborne and transferred contaminates become trapped in the new lubricant before it has even been put to use. Lubricants are tested for cleanliness before they leave the oil company and are assigned an ISO cleanliness code that physically determines the lubricant s level of cleanliness.
When the lubricant is placed in service, it will immediately ingest dirt in the lubricant transfer process. The lubricant being replaced will have left trace contamination to be absorbed by the new lubricant that will stay in suspension or chemically attach to the additive package. When left in this state the lubricant soon becomes saturated with contaminates and will act as an abrasive paste unless the lubricant is changed or set up to physically filter the contaminates out of the oil. Therefore, filtration plays two important roles in lubrication, 1) it allows the lubricant to perform its designed task, and 2) it prolongs the effective life of the lubricant prolonging the change out time.
When a lubricant is tested under an oil analysis program, one of the primary tests is an ISO cleanliness code that gives immediate insight into filtration and environmental control effectiveness.
ISO is an International Standards Organization governing body headquartered in Zurich, Switzerland, who design,...
